MELT GASIFIER SYSTEM

Abstract

A method to perform gasification in a gasification reactor is having a molten metal material disposed within a refractory lined vessel of the gasification reactor for converting a feed into product syngas by contacting feed into melt. A melt is formed by inductive melting by one or more induction coil apparatuses. A feed is injected into contact with the melt to dissolve at least a portion of the feed into the melt. A refractory-lined vessel is tilted at a pre-determined tilt angle about a horizontal plane to cause the refractory-lined vessel to be tilted at said pre-determined tilt angle from said horizontal plane during a conversion of the feed into a product syngas. A molten slag material is directed to flow away from the refractory-lined vessel at a predetermined molten slag material flow rate and product syngas is directed to flow from the refractory-lined vessel to a powerplant for electric power generation, a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof.

Description

The subject matter of the present specification relates to a method and apparatus for the gasification of cellulosic biomass, coal and other types of carbonaceous feed to produce low BTU syngas for downstream application such as electric power generation, or chemical upgrading into one or more determined syngas-derived product.

DESCRIPTION OF THE RELATED ART

The burning of refuse material in incinerators which use excess air to limit flame temperatures have produced large amount of effluent gases to be handled by gas cleaning equipment which must be of a tremendous size in order to handle the volume of gas generated. Other possible problems with regard to a known incinerator type of operation involves the filtration of incinerator fumes which have proved impractical because the odors generated are of a complex chemical nature not possible to filter out. Other absorption and catalytic agents including masking agents used as counter-odorents have proved equally unsatisfactory.

Examples of various gasifiers for solid biomass fuels are found in U.S. Pat. No. 4,531,462 to Payne; U.S. Pat. No. 4,848,249 to Lepori et al; U.S. Pat. No. 5,138,957 to Morey et al and U.S. Pat. No. 6,120,567 to Cordell et al.

Gasification technology has, for example, been actually utilized in a power plant integrated with coal gasification units, etc, with being oxygen or highly oxygen-enriched air is supplied to a coal gasification plant as a gasifying agent. However, consumption of the generated electric power in an auxiliary facility including an oxygen plant for producing such a gasifying agent is highly energy intensive. The gasification reaction typically involves delivering feed, free-oxygen-containing gas and any other materials to a gasification reactor which is also referred to as a “partial oxidation gasifier reactor” or simply a “reactor” or “gasifier.” Because of the high temperatures utilized, the gasifier is lined with a refractory material designed to withstand the reaction temperature.

The feed and oxygen are intimately mixed and reacted in the gasifier to form syngas. While the reaction will occur over a wide range of temperatures, the reaction temperature which is utilized must be high enough to melt any metals which may be in the feed. If the temperature is not high enough, the outlet of the reactor may become blocked with unmelted metals. On the other hand, the temperature must be low enough so that the refractory materials lining the reactor are not damaged.

Gasification systems and their associated gasifier apparatus have generally fallen into one of three classifications as follows: (1) updraft gasification; (2) downdraft gasification; and (3) crossdraft gasification. Under each classification a column of the solid fuel to be gasified is developed in a reactor or stack and air is passed through the column. As the fuel gasification proceeds the column gradually moves downwardly within the reactor or stack into a lower hearth zone. The air stream can be led in the same direction as the direction of fuel movement (downdraft gasification) or led in a direction opposite to the direction of movement of the descending fuel column (updraft gasification). If the air stream traverses the descending fuel column crossdraft gasification is promoted. Each method allows the fuel to gradually enter the hearth zone where highest temperature conditions subsist.

In the basic form of an updraft gasification system the fuel column rests on a grate through which a stream of air and steam passes. Above the grate a hearth zone develops with a reduction zone, a distillation zone and a drying zone lying sequentially above the hearth zone within the fuel column. The product gas is drawn off above the fuel column after having transferred some of its heat to the fuel in the distillation and drying zones in the upper part of the column. Only tar free fuels such as charcoal or anthracite are suitable for updraft gasification systems. If the fuel contains tar, as do wood, peat, lignite, etc., the tar is gasified and carried off with the syngas generated through the gasification system. A tar separator is then required to prevent the tars from fouling or otherwise adversely affecting downstream equipment.

In downdraft gasifiers such as U.S. Pat. No. 4,428,308, U.S. Pat. No. 4,306,506, the air stream enters the system in the area of the hearth zone (usually through nozzles arranged circumferentially or through a central nozzle) and draws all of the gaseous fuel components down into the hearth zone, there to enter into the gasification reactions. Tars and moisture are exposed at high temperature to the carbon in the hearth zone and undergo partial combustion and partial dissociation so that the final syngas leaving the system is tar free. Downdraft gasification systems have developed a characteristic funnel shaped constriction of the hearth at or just below the entry of the air stream. The hearth constriction or throat causes a localized increase in the air flow velocity which in turn causes localized high temperature conditions for conversion of the tars into their gaseous components.

Downdraft gasifier operation is generally unsuitable for fuels with high ash content because the high temperatures generated in the throat section of the hearth cause sintering of the ash into a slag which is difficult to remove and may cause functional problems in the system. In crossdraft gasification air is introduced through a small diameter high velocity nozzle and is projected across the fuel column to achieve a hearth zone of small volume but of very high temperature. Tar dissociation is limited because of the small hearth zone that is developed and therefore low tar fuels are preferred for crossdraft gasification.

Known industrial gas producers use separation, drying and grinding and other preparation prior to the actual gasification process with a downward gravitation flow of the refuse fuel and an upward flow of the gaseous and vaporous products. This upward flow of the vaporous products provides difficulty in the collection process and tends to harm the structure of the furnace due to the nature of the smoke products formed on the surfaces. Furthermore, these gasification apparatus' operate at pressures exceeding ambient atmospheric pressure such that leakage of noxious fumes can be a problem. One of the most common techniques of providing a conversion of biomass material to gas involves the use of a dumping of the material into container which has a grate near the bottom. The material is mixed with combustible air which is force-fed and the burning product produces the gas which is pumped away from the source. The purpose of the grate is to provide a surface which allows for a complete burn up of the product and the removal of the ash away from the combustion area.

Other construction such as shown by the patent to Giddings U.S. Pat. No. 3,746,521 disclose the removal of the waste material by means of a ram 41 which essentially functions to push out the material at the bottom of the combustion chamber. This construction of a ram, while providing for the removal of material does not function in an efficient manner with regard to the burning of the product because the ram pushes away material which may contain some product not fully burned and thus reduces the efficiency of the process. Thus the use of a grate in this type of biomass gasification process is seen to be the most reliable for efficiency of conversion and minimization of heat loss on already fully combusted products.

Known constructions involving the use of grates have mainly circular type grates which are placed at the bottom or near the bottom of a gasification chamber. These grates essentially must not only function to filter the completely combusted product but also must serve to aid or, in some cases fully support the suspension of the fuel material. That is these grates must be strongly constructed so that they can withstand the weight of the biomass which is being converted to gas. This can many times be a problem because of the nature of the material of the grate as well as the high temperatures involved in the process which could weaken the biomass suspension ability of the grate.

This is particularly true in large volume gasifiers where the weight of the biomass may become a problem on the grate structure. This problem is particularly relevant when the grate is of a circular construction due to the nature of the high temperatures which occur at the support device for the grates and at the surface of the grate. Possible problems involved in the known use of grate construction include the necessity for increasing the area of a circular grate each time the biomass handling capacity was to be increased which further increased the problem with regard to materials. Likewise the large circular zone designs for grates and therefore may pose problems for combustion zones with scaling production capacities and requires the use of complex gas removal and ash removal mechanisms. Processes for the production of a combustible gas from waste substances and other carbon-containing materials which are unsuitable or only inadequately suitable for direct combustion have long been known.

In one method of this kind (Austrian Patent Spec. No. 44467) the waste is burnt in a shaft furnace and for oxygen enrichment purposes the escaping gases are passed through another furnace filled with red-hot coke. Two alternately operated coke ovens are used to perform a continuous process, the waste gases escaping from whichever coke oven is being blown being fed to the combustion oven for the waste and being passed, together with the smoke or low-temperature carbonization gases expelled from the waste, through the hot coke in the other coke oven. In another known process for the production of a fuel gas free of carbon monoxide, from refuse and waste substances, with the simultaneous production of cyanogen compounds (Austrian Patent Spec. No. 1 664), the waste materials are heated to temperatures of between 800° and 1000° C. for partial conversion to smoke gases which are fed to a shaft reactor filled with reactive materials in a specific arrangement. In this shaft reactor the smoke gases are passed over hot paper ash to bring them to dissociation temperature and are passed over coke or other carbon-containing material in the dissociated state. The conversion of the smoke gases formed previously by the waste distillation takes place in these conditions.

Various entrained flow gasifiers are known, such as U.S. Pat. No. 4,531,949, a common problem for instance, is that the biomass materials are not prepared in a sufficiently contained area to prevent discharging of odours into the surrounding environment. Further inefficiencies arise when the biomass material is not prepared, gasified and subsequently completely combusted in a single environment with appropriate feedback and interaction between the various stages of the process.

In U.S. Pat. No. 4,959,080 a coal gasification process is described which may be performed in a gasification reactor as above. This publication describes that a layer of slag will form on the membrane wall during gasification of coal. This layer of slag will flow downwards along the inner side of the membrane wall. The Shell Coal Gasification Process also makes use of a gasification reactor comprising a pressure shell and a membrane walled reaction zone according to “Gasification” by Christofer Higman and Maarten van der Burgt, 2003, Elsevier Science, Burlington Mass., pages 118-120. According to this publication the Shell Coal Gasification Process is typically performed at 1500° C. and at a pressure of between 30 and 40 bar. The horizontal burners are placed in small niches according to this publication.

In the Shell Coal Gasification Process at the lower end of the above disclosed pressure range. It is however desirable to operate a gasification reactor at higher pressures because, for example, the size of the reactor (diameter and/or length) can then be reduced while achieving the same capacity.

A reduced diameter of the gasification reactor provides a smaller circumferential area for the slag running down the vertical membrane wall. At an equal reactor throughput the thickness of the fluid slag layer is increased thereby. This effect is even bigger by using high-ash feeds. It has been found that with increasing gas pressures and reduced reactor diameter, slag ingresses into the burner muffles. This slag deflects the oxygen/coal flame towards the metallic muffle walls, which causes extremely high heat fluxes. In combination with the higher overall surface temperatures steam blankets can be formed on the water cooling side, resulting in that locally no adequate cooling exists. This in turn may result in that at such locations the metal of the membrane wall melts away.

U.S. Pat. No. 4,818,252 describes a burner muffle as present in a membrane wall of a gasification reactor. The burner muffle itself can be adapted in design depending on the gasification conditions. The design comprises a vertical cooled shield comprised of interconnected concentric tubes around an opening for a gasification burner. This vertical concentric shield can be placed at different horizontal positions, i.e. closer to or further away from the membrane wall.

The burner muffle of U.S. Pat. No. 4,818,252 is however vulnerable to slag ingress, when the gasification reaction is conducted under conditions wherein a thick layer of viscous liquid slag forms on the inside of the membrane wall. In such a situation the slag will flow in front of the burner head and disturb the combustion. U.S. Pat. No. 4,818,252 discloses a slag deflector in FIG. 14 to avoid that slag covers the burner head. However, this design is not adequate to cope with thick layers of slag.

During pressure gasification of ash-containing feeds in dust form, in lumps or in liquid form, solid residues are formed from the feed ash as a function of the gasification temperature, said residues being formed either in the form of slightly molten granulated ash or in the form of fully molten slag and being evacuated from the pressure systems after cooling. Feed in dust form, in lumps or in liquid form is understood to refer to conventional feeds such as coals of various ranks, cokes of various origin, but also to solids-containing oils and tars as well as slurries that may be utilized as coal-water or coal-oil slurries or slurries obtained in the form of suspensions of pyrolysis coke and pyrolysis liquids from thermal pre-treatment using different pyrolysis methods of biomass.

Generally, the granulated ash or fully molten slag is cooled by injecting water and is collected in bulk form in a water bath, discharged from the pressure system through pressure lock hoppers and disposed of, or processed, into building materials. Such type methods and apparatus are described in European Patent No. EP 0 545 241 B1 and German Patent No. DE 4 109 231. EP 0 545 241 B1 describes a method for thermal utilization of waste materials, combining actually known process steps such as pyrolysis, comminution, classification, gasification and gas purification in which CO and H2 containing gas and a slag are formed in a gasification reactor, the slag granulating upon contact with water and being discharged from the gasification reactor.

DE 4 109 231 C2 describes a method of recycling halogen-loaded, carbon-containing waste materials by which waste materials are converted in the entrained flow, according to the principle of partial oxidation, to a carbon monoxide and hydrogen-containing crude gas. There is a water bath, in which the solidifying slag particles are received and discharged from the pressure reactor through a lock hopper, being disposed in the lower part of the reactor. This technology has major disadvantages leading to operation failures and limiting the availability of the technology as a whole. Such failures are e.g., due to the solidification of the ashes/slags in the water bath, which is promoted by the solid substances forming in a wide range of grain sizes. The solidification leads to the formation of bridges and blocks the evacuation process.

Molten bath gasiflers are also widely known for more than 50 years such as U.S. Pat. No. 4,496,369, U.S. Pat. No. 418,672, it is well known in the art that in molten bath gasifiers, molten metal reactors utilizing a single reaction zone, such as U.S. Pat. Nos. 4,496,369, 4,511,372, 4,574,714 and 4,602,574, may be deployed to gasify hydrocarbons. By operating in a single reaction zone, all of the above-mentioned gasifiers produce a single mixed-gas product in which the hydrogen and carbon monoxide are combined.

In the German Letters Patent No. 1,915,248, carbon fuel containing sulfur and preheated air are laterally introduced into a molten iron bath, through the walls of the stationary reactor using lances.

During the operation of a stationary reactor, difficulties can arise—particularly when nozzles are arranged in the bottom area of the reactor for introduction of the carbon fuel and air instead of the lances described above. Due to the gasification process, such nozzles tend to burn or wear off, or become corroded. In order to maintain efficient reactor operation, these nozzles must be occasionally cleaned or replaced. However, in order to clean or replace a malfunctioning bottom nozzle, a stationary reactor must be taken out of operation and be emptied of its molten metal. This naturally is costly in and of itself and additionally results in the loss of a great deal of operating time. These same difficulties also ensue when repairing other damage such as wash-outs or corrosion of the fireproof cladding of the reactor, particularly in the area of the phase boundary.

Rasor (in U.S. Pat. Nos. 4,187,672 and 4,244,180) describes a hydrocarbon gasification process in which solid hydrocarbons such as coal are lowered onto the surface of a molten iron bath zone in which high temperature cracking of the hydrocarbons into lighter molecular weight materials takes place and residual carbon is dissolved in the molten iron. The gaseous cracked hydrocarbon products are removed via outlets in the shaft through which the feed hydrocarbon solids drops onto the molten iron. The molten iron containing dissolved carbon is transferred to a second molten iron zone in which an oxygen-containing gas is introduced to convert the carbon into carbon monoxide and raise the temperature of the iron for transfer back to the feed zone. The carbon monoxide is further oxidized above the molten iron bath and heat is recovered via a boiler or similar system. Sulfur in the feed is removed via slag formation on top of the molten iron.

Tyrer (in U.S. Pat. No. 1,803,221) and Nixon (in U.K. Patent 1,187,782) describe in general terms two-zone gasifier processes that have the potential to produce a high-purity hydrogen-rich gas by introducing the hydrocarbon feed below the surface of the molten iron, thereby minimizing the production of cracked products. However, by operating at atmospheric pressure, these molten-metal gasifier processes produce hydrogen-rich and carbon monoxide-rich gases at atmospheric pressure, when in fact most industrial processes require that such gases be available at higher pressures, such as 5 to 100 atmospheres absolute or higher.

In the gasification of solid carbonaceous source materials such as coal, char, coke, and the like, a metal oxide such as zinc oxide has been employed to provide at least part of the oxygen required. Such techniques are disclosed in U.S. Pat. Nos. 2,592,377 and 2,602,809.

In some of these processes, a finely divided solid particle form carbonaceous material is admixed with zinc oxide as the oxygen carrier or oxygen donor according to the basic reaction:

C+ZnO→Zn+CO.

Formation of Zn vapor occurs in the gasification of the carbonaceous material such as char when using ZnO as the oxygen carrier or oxygen donor. It is necessary to cool the reaction products, which are gaseous, subsequent to the gasification. This leads to separation of Zn as a molten metal, and the gaseous CO, carbon monoxide, as the desired product.

Unfortunately, during cooling, formation of some zinc oxide also has been a partial result. Apparently, some reversion to the oxide of zinc occurs with consequent loss of a portion of the desired carbon monoxide. It is believed that zinc oxide forms due to the reversible reaction between zinc and traces of carbon dioxide, also present in the reaction product mixture in small concentrations:

Zn(g)+CO2(g)→ZnO(s)+CO(g)

The so-formed zinc oxide is an undesirable product since the zinc oxide tends to form a coating around droplets of molten zinc, depositing as a “blue powder” in zinc collection chambers, leading to line plugging, and preventing subsequent reoxidation of the metallic zinc inside the droplets for reuse.

Excessive amounts of solid zinc oxide mixed with molten zinc create serious problems of material transport and handling of the molten zinc. U.S. Pat. No. 2,342,368 teaches a process for reduction of zinc oxide by carbonaceous materials, teaching one effort to reduce or prevent formation of blue powder, but recycles carbon monoxide to the feed and to the zinc oxide/char reactor.

Blue powder has been a perennial problem in zinc handling for a long time. For example, the Encyclopedia of Chemical Technology (1970) in Vol. 22, page 579, in describing zinc metallurgy suggests chilling zinc vapor to avoid formation of blue powder, though there is no mention of a char gasification reaction.

Swedish Patent (Swedish patent application No. 7706876-5) describes such a process for production of gas, in which gas as well as crude iron are produced. It is in fact highly advantageous to use iron-ore concentrate as a cooling medium, and replace the melt of metals by continuous or intermittent discharge of melt and slag, whereby the sulphur content in the bath as well as the presence of other contaminants may be kept at a favourably low level.

Swedish Patent (Swedish patent application No. 8103201-3) describes a process in gasification of carbon in the form of carbon, hydrocarbons and/or hydrocarbon compounds, whereby carbon, oxygen and iron oxides, in which the iron oxides act as a cooling medium, are injected into the reactor, containing an iron melt, beneath the surface of the melt. Carbon is injected in stoichiometric excess in relation to the oxygen contained in the melt in the form of oxides. The iron melt has a carbon content such that it dissolves carbon. According to the process the reactor is brought to a total inner pressure of 2 to 50 bar, preferably 4 to 10 bar.

U.S. Pat. No. 5,112,527 issued to Kobylinski describes a process for converting natural gas to synthesis gas which utilizes ambient air as a source of oxygen. In the described process, a homogeneous mixture of lower alkanes and air is subjected to partial oxidation and steam reforming reactions in the presence of a first catalyst and water.

The product stream from the first catalyst reportedly reacts with water in the presence of a second catalyst having steam reforming activity to produce carbon monoxide and hydrogen. The Kobylinski patent states that the use of air as an oxygen source may result in up to about 45 volume percent nitrogen as an inert component in the gaseous, syngas-containing product.

European Patent Application No. 0399833A1, describes a reactor equipped with separation membranes to exclude nitrogen gas when the reactor is charged with atmospheric air. The reactor reportedly comprises first and second zones separated by a solid multi-component membrane. The '833 application states that such reactors can be used to conduct the partial oxidation of methane to produce unsaturated compounds or synthesis gas.

U.S. Pat. No. 4,062,657 issued to Knuppel et al. is directed to a process and an apparatus for gasifying sulphur-bearing coal in a molten iron bath. Reportedly, hot liquid slag is transferred from the iron bath to a second vessel in which the slag is desulfurized by contact with an oxygen containing gas, and then returned to the iron bath for reuse.

An article by L. Meszaros and G. Schobel in British Chemical Engineering. January 1971, Volume 16, No. 1 describes a molten-bed reactor having a molten lead bath which facilitates the simultaneous oxidation and decarboxylation of furfurol to produce furan. Furfurol and air were reportedly bubbled through molten lead in stoichiometric ratio from a common furfurol-air inlet system and, altematively, from a separate furfurol inlet and air inlet system. The article states that the method is useful for the partial oxidation of hydrocarbons, alcohols, aldehydes, and for the decomposition of natural gas and gasoline.

U.S. Pat. No. 4,406,666, issued to Paschen et al., is directed to a device for the gasification of carbon-containing material in a molten metal bath process to obtain the continuous production of a gas composed of carbon monoxide and hydrogen. The '666 patent states that gaseous carbon materials as well as gases containing oxygen can be introduced into the reactor below the surface of the molten metal bath. The molten metal reportedly consists of molten iron, silicon, chromium, copper, or lead.

A method for converting carbon-containing feed, such as municipal garbage or a hydrocarbon gas, to carbon dioxide is described in U.S. Pat. No. 5,177,304 issued to Nagel. The carbon-containing feed and oxygen are introduced to a molten metal bath having immiscible first and second molten metal phases. The '304 patent states that the feed is converted to atomic carbon in the bath, with the first metal phase oxidizing atomic carbon to carbon monoxide and the second metal phase oxidizing carbon monoxide to carbon dioxide. Heat released by exothermic reactions within the molten bath can reportedly be transferred out of the molten system to power generating means, such as a steam turbine.

U.S. Pat. No. 4,126,668 issued to Erickson presents a process for producing a hydrogen rich gas such as hydrogen, ammonia synthesis gas, or methanol synthesis gas. In the process, steam, carbon dioxide, or a combination of the two is reportedly reacted with a molten metal to produce a molten metal oxide and a gaseous mixture of hydrogen and steam. The '668 patent states that the steam portion of the gaseous mixture can be condensed and separated to produce a relatively pure hydrogen stream.

The molten metal oxide is said to be regenerated for further use by contact with a reducing gas stream containing a reformed hydrocarbon gas, such as reformed methane. When methanol is a desired product, appropriate amounts of carbon dioxide and steam are reportedly reacted with the molten metal, whereby CO2 is reduced to CO and H2O is reduced to H2 to produce a methanol synthesis gas. Alternatively, the '668 patent states that the relatively high purity hydrogen stream can be subsequently reacted with CO2 in a reverse water shift reaction to produce a methanol synthesis gas.

The use of molten salts in the combustion and gasification of carbonaceous materials is known. Thus, U.S. Pat. No. 3,710,737 to Birk, directed to a method for producing heat, discloses carrying out the combustion of carbonaceous materials in a molten salt medium in the form of an alkali metal carbonate melt containing a minor amount of alkali metal sulfate or sulfide. In such combustion reaction, the combustion of the oxygen and carbon occurs indirectly, as described in the above patent, and the alkali metal carbonate, such as sodium carbonate, provides a compatible salt medium at practical operating temperatures, retains heat for conducting the combustion reaction, and also reacts with and neutralizes acidic or undesirable pollutants such as sulfur-containing gases which are formed during combustion of carbonaceous materials, e.g. coal, containing impurities such as sulfur and sulfur-bearing compounds.

A similar reaction in such molten salt medium is disclosed in U.S. Pat. No. 3,708,270 to Birk et al, directed to a method of pyrolyzing carbonaceous material. A carbonaceous feed is thermally decomposed in a pyrolysis zone by heating it in the absence of oxygen to form char and a gaseous effluent. An optional steam input for gasification of the char material may also be utilized. In a heat generation zone, carbon and oxygen are reacted to form carbon dioxide to provide heat for the pyrolytic decomposition reaction.

In both of the above patents the reaction in the alkali melt is carried out to maximize heat generation so that the reaction product principally contains CO2, and also N2 where air is the source of oxygen. Thus, in these patents, particularly U.S. Pat. No. 3,710,737, it is noted that carbon monoxide formation is undesirable, and although provision is made for a separate furnace or burner to combust any carbon monoxide present, carbon monoxide is stated to be a minor product of the reaction.

The above patents point out that an excess of carbon is used, i.e., an amount of oxygen less than that stoichiometrically required for complete oxidation of the carbonaceous material is present in the melt, so that under steady-state operating conditions the sulfur present in the melt is maintained substantially all in the sulfide form. These conditions are employed in these patents not for purposes of obtaining incomplete combustion and formation of carbon monoxide, but in a manner so that substantially complete combustion of the char or coal to CO2 is achieved with as little production of CO as possible. Thereby a maximum amount of heat is obtained from the char or coal, most of this heat being generated in the molten salt.

The combustion and gasification of coal and other impure carbon containing fuels by carbonization and solution of the carbon in molten iron and its oxidation therein is known as a general process. The state of the prior art comprises, among others, the documents J. A. Kamavas, et al, in “ATGAS-Molten Iron Coal Gasification”, 1972 AGA Synthetic Pipeline Gas Symposium, Chicago, Ill., Oct. 30, 1972, as well as in Pelczarski, et al, U.S. Pat. Nos. 3,526,478 and 3,533,739.

U.S. Pat. No. 1,838,622 discloses the method and apparatus of a vertical distillation-pyrolysis chamber linked to a combustion chamber. Some solids from the vertical chamber enter the combustion chamber and the gaseous products of combustion (non-combustible) directly heat the vertical distillation-pyrolysis chamber. The vertical chamber apparatus treats carbonaceous material, acts as a fractionator, and allows reflux of distillation products. The material proceeds by gravity flow through the column, the chamber fractionates volatile components, refluxing is provided to control the heat distribution within the column, heated gas may be introduced to heat material within the column, the process is continuous, and the column may be characterized as differential.

U.S. Pat. No. 1,759,821 discloses destructive distillation of carbonizable material in a retort in which material moves downward continuously and volatile components are fractionated.

U.S. Pat. No. 1,669,023 discloses carbonization and distillation of coal in a vertical chamber. Heat is supplied by upwardly flowing gas and gas may be added to points along the chamber to regulate the temperature distribution.

U.S. Pat. No. 3,109,781 discloses semi-continuous gravity flow of hydrocarboniferous material through a retort heated by injection of hot noncombustion-supporting gases at the lower end. Volatile components exit at the top end of the retort and enter a fractionator.

U.S. Pat. No. 3,838,015 discloses pyrolytic decomposition of trash in which air is admitted at a controlled rate to maintain combustion of gases produced and therefore regulate the pyrolysis temperature.

U.S. Pat. No. 3,886,048 discloses carbonizing and desulfurizing carbonaceous material by heating carbonaceous material admixed with iron in a reducing atmosphere and then subjecting the resulting char to an oxidizing atmosphere.

U.S. Pat. No. 2,787,584 discloses continuous carbonization of solid carbonaceous material by suspending the material in a moving molten stream at greater than 800° C. An overhead stream of volatized chemicals and coke which is gravity separated from the molten metal are produced.

U.S. Pat. No. 3,890,908 discloses pyrolytic reduction of carbonaceous waste material by floating it up through a molten metal bath.

U.S. Pat. No. 1,734,970 discloses flow of carbonaceous material through a molten iron bath to produce volatile and nonvolatile products.

U.S. Pat. No. 2,953,445 discloses a two-chamber molten slag bath reactor for the production of water gas from a carbonaceous raw material. Gasification of the raw material and carburization of the bath occur in one chamber and combustion occurs in the other. Air or steam may be introduced into the bath through the walls of the bath or above the surface level of the bath (in the combustion chamber), the inlet being arranged tangentially so that the medium is set in circular motion between the chambers which are divided by gastight partitions.

Previously mentioned U.S. Pat. No. 3,533,739 discloses combustion of sulfur-bearing carbonaceous fuel by subsurface injection of the fuel and preheated air into a molten bath. Sulfur is extracted by the addition of lime and the main product of combustion is carbon monoxide. Carbon monoxide product may undergo combustion by injection of air. Heat combustion may be transferred to steam which drives power turbines.

U.S. Pat. No. 1,803,221 discloses apparatus and process for the production of hydrogen gas from methane-containing gases in a molten iron bath. The molten iron bath is divided into two parts by a partition wall which separate gaseous zones but leaves the molten iron free to circulate. Feed gas is blown in below the surface on one side of the partition and air is blown in on the other side. (The air may be blown in tangentially so as to cause the iron to circulate).

U.S. Pat. No. 1,592,861 discloses production of water gas by adding carbonaceous material to a molten bath, passing steam through the bath, maintaining bath circulation to promote absorption of incoming carbon into the bath. U.S. Pat. No. 1,592,860 discloses production of carbon monoxide by charging iron ore and coal or other fuel into a tower and allowing the mass to rest on the surface of the molten bath (held up by the buoyant force) followed by absorption of carbon into the bath and metal reduction.

U.S. Pat. No. 3,084,039 discloses blowing a stream of free oxygen-containing gas across the surface of a molten iron bath containing carbon to produce carbon monoxide gas.

U.S. Pat. No. 314,342 discloses manufacture of hydrogen gas by continuous introduction of carbonaceous material, simultaneously with steam, into a chamber containing a metallic oxide, followed by treatment of gaseous products with lime.

U.S. Pat. No. 3,933,128 discloses combustion of carbonaceous fuel dissolved in a molten salt to produce heat which may be used to generate steam to drive power turbines.

U.S. Pat. No. 2,876,527 discloses the cracking and dispersion of heavy hydrocarbon feedstocks in molten alkali metal carbonate baths followed by gasification of the dispersed material by contacting with oxygen, steam, or CO2 at 3000° F. Cracking and combustion occur in separate vessels.

U.S. Pat. No. 3,933,127 discloses a means of sulfur removal from carbonaceous fuel during combustion. Fuel, a collector, and oxygen are introduced into a molten bath of salt. The collector forms a sulfur compound which is insoluble in molten salt.

U.S. Pat. No. 3,812,620 discloses the cooling of the outer metal shell of a molten metal bath by circulation of fluid through a plurality of passages within the shell. A layer of refractory material lies between the bath and the outer metal shell.

DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an isometric view of the gasifier system of example 1,

FIG. 2 shows a cross-section of the gasifier system of example 1,

FIG. 3 shows a cross-section of the gasifier system of containing a molten akali melt of example 3,

FIG. 4 illustrates the gasifier system of example 4,

FIG. 5 shows a top view of the gasifier system of FIG. 4,

FIG. 6 shows a partial view comprising a vessel of the gasifier system of FIG. 4,

FIG. 7 shows a first cross section of the vessel of FIG. 6,

FIG. 8 shows a second cross section of the vessel of FIG. 6 which is perpendicular to the first cross section,

FIG. 9 illustrates tilting angles of a reactor vessel according to the present specification,

FIG. 10 shows a tilted reactor vessel according to the present specification,

FIG. 11 shows an ash removal section of a molten metal gasification system according to a further embodiment,

FIG. 12 shows a molten metal gasification system according to a further embodiment, and

FIG. 13 shows a molten metal gasification system according to a further embodiment.

Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about,” is not limited to the precise value specified. In some instances, the approximating language may correspond to the precision of an instrument for measuring the value. In some instances, the term about can denote a value within a range of ±10% of the quoted value.

Terms “heating value,” “calorific value,” “caloric value,” are interchangeably used within this description.

Feed, as used herein throughout the specification and claims, may refer to coal, biomass, municipal solid waste, refuse-derived fuel (RDF), industrial waste, sewage, raw sewage, peat, scrap rubber, shale ore, tar sands, crude oil, natural gas, low-BTU blast furnace off-gas, flue gas exhaust, or a combination thereof.

Refuse-derived fuel (RDF), which is generally produced by shredding municipal solid waste, consists largely of organic components of municipal waste such as plastics and biodegradable waste. Non-combustible materials such as glass and metals are removed mechanically and the resultant material compressed into pellets, bricks, or logs and used for conversion to combustible gas, which can itself be used for electricity generation or the like. Coal refers to a common fossil fuel, the most common classification is based on the calorific value and composition of the coal. Coal is of importance as a fuel for power generation now and in the future since there are a lot of coal reserves, and the coal reserves are hardly unevenly distributed over the world.

ASTM (American Society for Testing and Materials) standard D388 classifies the coals by rank. This is based on properties such as fixed carbon content, volatile matter content, calorific value and agglomerating character. Broadly, the coals can be categorized as “high rank coal” and “low rank coal,” which denote high-heating-value, lower ash content and lower heating value, higher ash content coals, respectively.

Low-rank coals include lignite and sub-bituminous coals. These coals have lower energy content and higher moisture levels.

High-rank coals, including bituminous and anthracite coals, contain more carbon than lower-rank coals and correspondingly have a much higher energy content. Some coals with intermediate properties may be termed as “medium rank coal.” The term biomass covers a broad range of materials that offer themselves as fuels or raw materials and are characterized by the fact that they are derived from recently living organisms (plants and animals).

This definition clearly excludes traditional fossil fuels, since although they are also derived from plant (coal) or animal (oil and gas) life, it has taken millions of years to convert them to their current form. Thus the term biomass includes feeds derived from material such as wood, woodchips, sawdust, bark, seeds, straw, grass, and the like, from naturally occurring plants or purpose grown energy crops.

It includes agricultural and forestry wastes. Agricultural residue and energy crops may further include husks such as rice husk, coffee husk etc., maize, corn stover, oilseeds, cellulosic fibers like coconut, jute, and the like. Agricultural residue also includes material obtained from agro-processing industries such as deoiled residue, gums from oil processing industry, bagasse from sugar processing industry, cotton gin trash and the like. It also includes other wastes from such industries such as coconut shell, almond shell, walnut shell, sunflower shell, and the like.

In addition to these wastes from agro industries, biomass may also include wastes from animals and humans. In some embodiments, the biomass includes municipal waste or yard waste, sewage sludge and the like. In some other embodiments, the term biomass includes animal farming byproducts such as piggery waste or chicken litter. The term biomass may also include algae, microalgae, and the like. Thus, biomass covers a wide range of material, characterized by the fact that they are derived from recently living plants and animals. All of these types of biomass contain carbon, hydrogen and oxygen, similar to many hydrocarbon fuels; thus the biomass can be used to generate energy.

Exemplary embodiment according to the present specification.

Reaction Scheme and Modeling

Based on analysis of the global reaction parameter incorporating petcoke, coal, biomass feeds, the main reactions are hereby provided:

Feeds with High Volatile Content:

CH4+12O2→CO+2H2

CH4+H2O→CO+3H2

Global Rate Limiting Parameters:

H2+0.5O2→H2O

CO+H2O3CO2+H2

Dependence on temperature during gasification would provide the following reactions comprising:

C(s)+0.5O2(g)→CO(g)

C(s)+H2O(g)→CO(g)+H2(g)

C(s)+CO2(g)→2CO(g)

Therefore, typical gasification reactions of coal/biomass can be represented by the following equations:

Coal→Char(C)+CH4+H2+CO  (1)

C+O2→CO2  (2)

C+CO2→2CO  (3)

C+H2O→H2+CO  (4)

CO+H2OCO2+H2  (5)

The pyrolysis reaction (1) and the shift reaction (5) take place relatively rapidly and the combustion reaction (2) is completed in very short time. But the reactions (3) and (4) are slow in reaction rate compared with the rest of the reactions and take much time for gasification. Therefore the improvement in gasification efficiency depends on how to make the reactions (3) or (4) faster. The reaction rate in the reaction (3) or (4) is influenced by the reaction temperature, partial pressures of gasifying agents, properties of coal particles, etc. According to the gasification processes mentioned above, optimum conditions are not always employed, so that char is discharged from a gasifier.

Computational fluid dynamics (CFD) determination of the above reaction parameters are based on the following well-known conservation equations for mass and momentum, expressing mass conservation by;

$\begin{array}{cc}\frac{\partial }{\partial t}\left({\rho }_f\right)+\frac{\partial }{\partial x_j}\left({\rho }_fU_j\right)=0& \left(A\right)\end{array}$

and fluid momentum conservation by;

$\begin{array}{cc}\frac{\partial }{\partial t}\left({\rho }_fU_i\right)+\frac{\partial }{\partial x_j}\left({\rho }_fU_jU_i\right)=-\frac{\partial }{\partial x_i}p+\frac{\partial }{\partial x_j}{\tau }_{\mathrm{ji}}+{\rho }_fg_i& \left(B\right)\end{array}$

where ρ_f is fluid density, U_f is fluid velocity, p is fluid pressure, g is the specific gravity and τ_ij is the fluid stress tensor. When the fluid stress tensor τ_ij is known, such as for a Newtonian fluid, the single-phase flow can be predicted by numerical solution of (A) and (B).

In the various embodiments according to the present specification a mixture of steam, air/oxygen and biomass/coal/wood particles are approximated in the CFD numerical calculation as follows:

In one configuration, the feed in the form of crushed or pulverized particles are entrained within a carrier gas such as steam, oxygen, air, or a combination thereof into contact with the melt via at least one lance device/apparatus.

Based on the selected Eulerian representation of (the wood/biomass/coal particles dispersed in a fluid containing steam-vapor droplets), given by the equations (A) and (B).

The flow phase is represented as a continuous field.

Transport equations for the phases appear from volume averages of the fluid and particles in a control volume (within the gasification zone of the gasifier). For a gas-particle system typical transport equations that appear are for mass conservation:

$\begin{array}{cc}\frac{\partial }{\partial t}\left({\rho }_f{\alpha }_f\right)+\frac{\partial }{\partial x_j}\left({\rho }_f{\alpha }_fU_j\right)=0& \left(C\right)\end{array}$

and for fluid momentum:

$\begin{array}{cc}\frac{\partial }{\partial t}\left({\rho }_f{\alpha }_fU_i\right)+\frac{\partial }{\partial x_j}\left({\rho }_f{\alpha }_fU_jU_i\right)=-{\alpha }_f\frac{\partial }{\partial x_i}p+{\alpha }_f\frac{\partial }{\partial x_j}{\tau }_{\mathrm{ji}}+{\rho }_f{\alpha }_fg_i+{\alpha }_p\beta \left(V_i-U_i\right)& \left(D\right)\end{array}$

The volume fraction of fluid α_f and the inter-phase friction factor β (drag term) appear from the volume averages of (A) and (B).

For particle mass balance:

$\begin{array}{cc}\frac{\partial }{\partial t}\left({\rho }_p{\alpha }_p\right)+\frac{\partial }{\partial x_j}\left({\rho }_p{\alpha }_pV_j\right)=0& \left(E\right)\end{array}$

and for particle momentum:

$\begin{array}{cc}\frac{\partial }{\partial t}\left({\rho }_p{\alpha }_pV_i\right)+\frac{\partial }{\partial x_j}\left({\rho }_p{\alpha }_pV_jV_i\right)=-\frac{\partial }{\partial x_i}p^s+\frac{\partial }{\partial x_j}{\tau }_{\mathrm{ji}}^s+{\rho }_p{\alpha }_pg_i-{\alpha }_p\frac{\partial }{\partial x_i}p+{\alpha }_p\frac{\partial }{\partial x_j}{\tau }_{\mathrm{ji}}+{\alpha }_p\beta \left(U_i-V_i\right)& \left(F\right)\end{array}$

α_p is the volume fraction of particles. Because of inter-particle collisions and momentum exchange due to collisions both the solids pressure p^s and the solid particle internal stress τ_ji^s is included in the equations.

The velocities are now averages from small control volumes and are no longer the instantaneous velocities given in the equations (A) and (B). In a swarm of large particles the fluid velocity close to the particle surface is very different from the volume-averaged velocity. However, the effects of the local variations will in practice only affect the interphase transfer terms such as drag and mass transfer.

In another reactor configuration, where the feed is injected into contact with the melt from below its surface by means of one or more conduits such as tuyeres, fluid dynamics would have to be expressed in the general form of:

$\frac{{\Phi }_{\mathrm{CM}}}{t}=\frac{}{t}{\int }_{V_{\mathrm{CM}}\left(t\right)}^{}\phi V={\int }_{V_{\mathrm{CV}}\left(t=t_0\right)}^{}\frac{\partial \phi }{\partial t}V+{\int }_{A_{\mathrm{CV}}\left(t=t_0\right)}^{}\phi \left(\overrightarrow{v}-{\overrightarrow{v}}_{A_{\mathrm{CV}}}\right)·\overrightarrow{n}A\stackrel{v_{\mathrm{CV}}\ne f\left(t\right)}{\to }{\int }_{V_{\mathrm{CV}}}^{}\frac{\partial \phi }{\partial t}V+{\int }_{A_{\mathrm{CV}}}\phi \overrightarrow{v}·\overrightarrow{n}A$

Note that F may be mass, momentum, or energy in a control mass CM, and

A continuity equation is the mass balance (dm_CM/dt=0) for a d V system;

$\frac{D\rho }{\mathrm{Dt}}+\rho \nabla ·\overrightarrow{v}=0$

The momentum equation is the linear-momentum balance (d(m{right arrow over (v)})_CM/dt={right arrow over (F)}={right arrow over (F)}_V+{right arrow over (F)}_A), applied to a dV system; with φ=ρ{right arrow over (v)} we get from the generalized equation above, using the convective derivative:

$\rho \frac{D\overrightarrow{v}}{\mathrm{Dt}}=\frac{\partial \left(\rho \overrightarrow{v}\right)}{\partial t}+\nabla ·\left(\rho \overrightarrow{v}\overrightarrow{v}\right)=\nabla ·\stackrel{\_}{\stackrel{\_}{\tau }}+\rho \overrightarrow{g}=-\nabla \left(p+\rho \mathrm{gz}\right)+\nabla ·\stackrel{\_}{\stackrel{\_}{{\tau }^{\prime }}}$

where τ is the stress tensor (such that the force per unit area of normal vector {right arrow over (n)} is {right arrow over (f)}= τ·{right arrow over (n)}), {right arrow over (g)} is any volumetric force field (e.g. gravity), p is fluid pressure (one third of the trace of the stress tensor), and τ′ the viscous component of the stress tensor.

The energy equation should be expressed as follows:

Energy balance (d(me)_CM/dt={dot over (Q)}+{dot over (W)}) for a dV system; with φ=ρe:

$\rho c_p\frac{\mathrm{DT}}{\mathrm{Dt}}=-\nabla ·\overrightarrow{\stackrel{•}{q}}+\alpha \mathrm{TDp}/\mathrm{Dt}+{\stackrel{\_}{\stackrel{\_}{\tau }}}^{\prime }:\nabla \overrightarrow{v}$

The above is expressed in terms of temperature of the melt.

The multiphase approach outlined above can be easily modified to suit the reactor (gasifier) operating pressure and the flow field fluid velocity (thus the gasification agent superficial gas velocity), providing a highly flexible and scalable means to perform gasification of the coal/biomass/wood particles in numerous gasifier configurations such as an entrained flow burner or a melt bath (molten iron) gasifier.

In another embodiment according to the present specification, some common metal reduction-oxidation reactions can be generalized as follows:

3Fe2O3+CO→2Fe3O4+CO2

Fe3O4+CO→3FeO+CO2

FeO+CO→Fe+CO2

Iron as a selected gasification medium:

Iron can exist in three forms—

α . . . BCC crystal with crystal dimension a=2.86 Angstrom exists at temperatures up to 910 oC, γ . . . FCC crystal with crystal dimension a=3.65 Angstrom exists at temperature range 910 oC to 1403 oC, δ . . . BCC crystal with crystal dimension a=2.93 Angstrom exists at temperature range 1403 oC to 1535 oC, molten iron due to its large thermal gradient and excellent heat transfer characteristics, is an ideal gasification media to which carbonaceous material is gasified via thermal decomposition/partial oxidation but also aided by various chemical reactions that can optimize in-situ (reactor) treatment of the evolved syngas compound composition for subsequent downstream application.

Although the maximum solubility of carbon in solid solutions in 2.0%, carbon is even more soluble in liquid iron, the range of compositions from 2% to 4.5% carbon gives rise to the very important group of engineering materials called cast irons.

At very high temperatures, a radical change takes place: the iron begins to absorb carbon rapidly, and the iron starts to melt, since the higher carbon content lowers the melting point of the iron. A principal factor influencing the properties of gray iron is the free sulfur present in the molten iron bath. Free sulfur (or free manganese) is the amount present in uncombined form at the onset of solidification. This can be defined by using the solubility product data. The solubility of manganese sulfide in liquid will vary with composition and temperature:

Log 10(% Mn×% S)=−1,920/T (T=Kelvin)

Liquidus and solidus temperatures can be derived from empirical equations to predict carbon equivalent (CE) in iron alloys and are expressed in the following;

% CE=0.096−0.0043TL+0.0056TS

% Si=−49.06+0.0157TS+0.0139TE

% C=% CE−⅓% Si

TL is liquidus temperature, TS is solidus temperature and TE is the eutectoid temperature. For iron alloy compositions where the TS−TL values are unknown or cannot be obtained from its cooling curve dataset, then a sample can be taken and its values derived. Electrical volt reading of the sample can be expressed as follows:

% CE=4.5010−0.22813 (mVL−mVs) the mVL being the thermocouple mVolt value that corresponds to its liquidus temperature and the mVs being the thermocouple mVolt value that corresponds to its solidus temperature.

Relationship Between Manganese—Slag Interface of Iron Bath

Base chemistry of the molten iron bath together with the basicity of its accompanying slag system has a significant impact on gasification of any given feed material, thus, conditioning and controlled manipulation of both the iron bath and slag system pre or post formation can affect its subsequent steady-state process operations.

If a manganese content is selected for a given gray iron composition, the sulfur level, which is in equilibrium with this manganese level, can be obtained from that curve. If average sulfur content is known, a manganese level could be obtained, which would avoid MnS precipitation. This principal can be applied to an example of gray iron with a carbon equivalent of 4.1 and sulfur at 0.09%. The liquidus temperature of 1,175 C is obtained. The solubility product curve for the liquidus can be obtained. With a sulfur level of 0.09%, equilibrium is established with a manganese level of 0.52%.

In turn, at manganese content of 0.52%, reducing sulfur below 0.09% will under these conditions, MnS precipitation will occur at a temperature below the liquidus. This temperature can be calculated using a manganese level and a sulfur level slightly below 0.52% and 0.09%.

In numerous conventional and existing gasification processes, the gasifier refractory lining lifespan is crucial to both gasifier availability and refractory replacement expense, for high temperature gasification, the problem is more pronounced as the choice of liner will determine the overall reliability, associated costs and operational availability of the overall system.

The higher affinity between manganese and sulphur as compared to iron is highly advantageous as sulphur present in the feedstock will be predominantly present in the slag layer of the iron bath, this is especially so if the slag chemistry (such as slag components MgO, CaO, Al.sub.2.O.sub.3 and SiO.sub.2) during iron bath operation is insufficient to produce sulphur oxides.

The trace FeO thus will react with existing non-ferrous compounds such as Mn, Si to initiate the slag system right from the beginning at formation of the molten iron bath to specified slag basicity. Further to note is the effect on slag viscosity based on the level of FeO present in a CaO—SiO.sub.2-Al.sub.2.O.sub.3-MgO—FeO slag system, where an increased FeO content at a fixed CaO—SiO.sub.2 basicity will exhibit lower viscosity, in slags with high viscosity heat is preserved within the melt as the refractory properties of the slag is incrementally higher than a low viscosity slag of basicity of about 1.4.

Therefore, while the CaO—SiO ratio determines basicity of the slag, FeO plays a role in determination of the slag's viscosity.

In some cast irons the silicon and manganese levels present in its solid phase may range from Si 1.5 to 2.0% wt and Mn from 0.5 to 1.0%, and while energy fuel expenditure for such cast iron charge materials are lower during reactor start-up, the formation of the molten iron bath and in combination with the stirring action of the oxidizer gas will cause formation of SiO and MnO in the slag layer right above the molten iron bath surface, contributing to limited but severe erosion of the refractory lining in the reactor.

The heat of reaction (ΔH), or enthalpy, determines the energy cost of the process. If the reaction is exothermic (ΔH is negative), then heat is given off by the reaction, and the process will be partially self-heating. If the reaction is endothermic (ΔH is positive), then the reaction absorbs heat, which will have to be supplied to the process. The Gibbs free energy (ΔG) of a reaction is a measure of the thermodynamic driving force that makes a reaction occur. A negative value for AG indicates that a reaction can proceed spontaneously without external inputs, while a positive value indicates that it will not. The equation for Gibbs free energy is:

ΔG=ΔH−TΔS

where ΔH is the enthalpy change in the reaction, T is absolute temperature, and ΔS is the entropy change in the reaction. The enthalpy change (ΔH) is a measure of the actual energy that is liberated when the reaction occurs (the “heat of reaction”). If it is negative, then the reaction gives off energy, while if it is positive the reaction requires energy. The entropy change (ΔS) is a measure of the change in the possibilities for disorder in the products compared to the reactants.

An Ellingham diagram is a plot of ΔG versus temperature. Since ΔH and ΔS are essentially constant with temperature unless a phase change occurs, the free energy versus temperature plot can be drawn as a series of straight lines, where ΔS is the slope and ΔH is the y-intercept. The slope of the line changes when any of the materials involved melt or vaporize. (note that free energy of formation is negative for most metal oxides).

The position of the line for a given reaction on the Ellingham diagram shows the stability of the oxide as a function of temperature. Reactions closer to the top of the diagram are the most “noble” metals (for example, gold and platinum), and their oxides are unstable and easily reduced. As we move down toward the bottom of the diagram, the metals become progressively more reactive and their oxides become harder to reduce.

When using carbon as a reducing agent, there will be a minimum ratio of CO to CO2 that will be able to reduce a given oxide. The main reactions within the molten iron agent are similar to that of the common gasification reactions that occur in today's conventional processes, namely the partial oxidation of carbon expressed as follows:

C(s)+0.5O2(g)→CO(g)

C(s)+H2O(g)→CO(g)+H2(g)

C(s)+CO2(g)→2CO(g)

H2O→0.5O2+H2

Direct Reduction

FeO(s)+C(s)→Fe(s)+CO(g)

Moisture contained within the feed is gasified in accordance with the following reaction chemistry:

Fe(s)+H2O(l)→FeO(s)+H2(g)

Various slag/gasification chemistry are as follows (where cast iron 3-4.5% carbon is utilized):

CaCO3→CaO+CO2

MgO.Al2O3(s)→Mg(s)+2Al(s)+4O

Mg(s)+CO(g)→MgO(s)+C(s)

Typical composition of the syngas produced may be as follows:

Analysis Trace
CO       H.sub.2.S (<ppm)
CO.sub.2 HCl (<ppm)
O.sub.2  CH.sub.4 (<ppm)
H.sub.2  CxHy (<ppm)
N.sub.2  total Sulphur (<ppm)

In configurations where the oxidizer gas is air, nitrogen may be between 40-50% of the gas composition, while trace gases such as methane, hydrocarbons are very low due to the high temperature of the syngas evolved from the molten iron bath.

The sulphur level (which can be 80-50 ppm or lower) is dependent on the slag chemistry deployed in the reactor and CO/H.sub.2 ratio would be determined with a number of reaction parameters.

In carbonaceous feeds where moisture content is 40-50% such as those in municipal solid waste streams, then the H.sub.2/CO (hydrogen to carbon monoxide) ratio may be marginally higher than the typical 1.0 range when the reactor is gasified at slightly below 1 ATM absolute. Other trace gases may include mercury, which is largely dependent on the feed composition. It should be noted that due to the high reaction temperature there is virtually no trace of HCl, light hydrocarbons, or H.sub.2.S the slag system further contributing to oxide reactions within.

The text below is a summary of various experimental work conducted by the current applicant onboard a 550DWT barge in 2 gasification reactor configurations using melt baths and a coupled medium frequency induction melter having a crucible capacity of 1 metric ton. Various reaction kinetics and rate constants were developed into a usable set of gasification reaction control parameters. Subsequent CFD (computational fluid dynamics) simulation can therefore be implemented using the same.

Example 1

FIG. 1 illustrates a known apparatus 10 implemented in accordance with the present specification. The apparatus 10 includes a digestor 12, a reactor 14 and an energy extractor 16.

A feed 18 which yields carbon upon being heated above a carbonization temperature thereof and which is solid at ambient temperature is fed into a top end 20 of the digestor as for example, via a conventional transport belt 22. The feed 18 can comprise any of a number of materials or mixtures thereof. For example the feed can comprise raw coal, undifferentiated industrial and municipal waste, animal and agricultural waste, sewage sludge, tar residues, asphalt residues, oil shale, and the like. The only essential characteristic of the carbon containing fuel is that it be such that upon being heated to a carbonization temperature in a manner which will be described in following, it is converted into carbon, and that at ambient or room temperature, e.g., 20° C., it is solid.

The term solid is used broadly herein to include glassy solids such as tar, asphalt and the like. It should also be noted that the feed can include non-carbonaceous materials such as scrap iron, limestone or the like, intermixed therewith and may even advantageously contain one or more of these materials for reasons which become apparent from the description which follows.

The feed 18, after passing into the top end 20 of the digestor 12, then proceeds downwardly therethrough under the influence of gravity feed. While within the digestor 12, the feed is converted into a generally contiguous mass 24 because of heat supplied to a bottom end 26 of the digestor 12 and to a first end 28 of the mass 24. Within the digestor 12, a temperature gradient is created in the mass 24 with a higher temperature at the first end 28 thereof and a lower temperature at a second end 30 thereof. Any volatile components of the feed 18 are progressively volatilized and, basically, the digestor 12, serves as a distillation and partial thermal cracking column for the feed 18. A plurality of takeoff means 32 are provided along the length of the digestor 12 and hence along the length of the mass 24. The highest of the takeoff means 32 receives the most volatile gases emitted by the mass 24 within the digestor 12, for example, hydrogen, methane and water vapor. The lower of the takeoff means 32 progressively receive higher molecular weight volatizable hydrocarbons produced by distillation, thermal decomposition, and/or cracking, and/or reforming of the feed 18 within the mass 24.

Turning now to a consideration of the reactor 14, said reactor 14 includes a liquid 34 therewithin which the first end 28 of the mass 24 contacts. The liquid 34 is a solvent for carbon and fills the reactor 14 up to a liquid level 36 therein, which liquid level 36 is below a top 38 of the reactor 14. The reactor 14 preferably includes baffle means 40 which completely separate the reactor 14 above the liquid level 36 into a carbonization chamber 42 and oxidation chamber means 44. The baffle means 40 are made to terminate below the liquid level 36 and above a bottom 46 of the reactor 14. This allows flow of the liquid 34 between the carbonization chamber 42 and the oxidation chamber means 44. A plurality of conduits 48 serve as means for introducing oxidizing gas means having an oxygen content into the oxidation chamber means 44 and against the liquid level 36, generally aimed to cause flow of the liquid 34 between the carbonization chamber 42 and the oxidation chamber means 44 and thus serves as means for forcing convection of the liquid 34 within the reactor 14. Means are also provided for conducting away a first hot gas from the oxidation chamber means 44. The means for conducting the first hot gas in the embodiment illustrated in FIG. 1 comprises a takeoff pipe 52.

Turning particularly to the oxidizing means, it should be noted that this oxidizing means should be such that it reacts overall in an exothermic manner with the carbon dissolved in liquid 34 to form carbon monoxide gas, thus keeping the temperature of the liquid 34 high enough to remain molten and be above a carbonization temperature of the mass 24 of the feed 18. Any number of oxygen containing gases are suitable as the oxidizing means of the present specification. For example, air is particularly suitable if it is preheated sufficiently by the exhaust gases or other means to maintain the liquid 34 in the liquid state. If the oxidizing gas has a much higher free oxygen content than air, for example more than 50%, the reaction is so strongly exothermic that it may be desirable to mix said gas with steam or to independently add steam, which itself will oxidize the carbon in the liquid 34 to form carbon monoxide gas along with hydrogen gas. Since the reaction of steam with the carbon in the liquid 34 is endothermic, its addition moderates the reaction so that it is not overly exothermic and so that the liquid 34 remains within the said desirable temperature range. It is also contemplated that a metal oxide ore, e.g., iron oxide, can be added to the liquid 34 wherein it will serve as part or all of the oxidizing means and will oxidize the carbon to form carbon monoxide gas and will itself be converted to the metal, e.g., iron, which can be recovered from the reactor 14 within a desirable temperature range, for example, in a range from about 1200° C. to about 1700° C.

The liquid 34 can be any liquid which will serve as a solvent for carbon and which will bind oxygen thereto either by chemical reaction therewith or by significantly dissolving the oxygen therein. For example, the liquid 34 can be a molten carbonate salt or iron or an iron containing alloy. An iron based liquid 34 has been found to be especially desirable and practical for carrying out the various processes of the present specification. It should be noted that when the liquid 34 is iron, makeup scrap iron and the like can be added to the digestor 12 along with the feed 18 to react with and remove impurities such as sulfur from the feed and prevent such impurities from being evolved with the valuable gases during the carbonization process. Feed streams such as coal and trash have a natural iron content. Such a throughput of iron ensures that the composition of the liquid 34 will stay substantially constant. When such an iron throughput exists, a tap 54 will generally be provided as a part of the reactor 14 for the removal of some of the liquid 34 and its eventual reprocessing in metallurgical refineries. In this manner, the composition of the liquid 34 can be kept substantially constant while various metals and the like which may become concentrated therein can be constantly stripped off and recovered via metallurgical processing.

Turning now to the energy extractor 16, it will be apparent that it receives a hot gas via the takeoff pipe 52 and then directly makes use of the energy content of that hot gas to generate power. For example, in a first energy conversion stage 56, the hot gas from the oxidation chamber means 44 can generate electrical power efficiently via gas turbine operation, thermionic energy generation or other advanced topping cycle energy generation. The hot gas is cooled somewhat by the energy removed in the first stage 56, whereupon the somewhat cooled hot gas can pass to a second energy conversion stage 58 after air has been injected thereinto via an air injector 60 to combust a portion of the hot gas and reheat the hot gas to its original temperature or another pre-determined elevated temperature.

In the second stage 58, electrical power can be generated more efficiently at the original high temperature than at the somewhat lowered temperature. From the second stage 58, the again somewhat cooled gas can pass on to a third energy conversion stage 62 via an intermediate air injector gas burner 64 which will raise the temperature of the gas again through chemical reaction whereby additional energy may be extracted efficiently in the third stage 62. If desired, the hot gas from the third stage 62 can pass through a heat exchanger 65 wherein the heat thereof is used to super heat steam conducted to an electric power plant or to heat feed water and/or air, with the feed water being used for any desired process and the air being used, for example, as the air injected via the plurality of conduits 48 into the oxidation chamber means 44.

Such staged combustion by air injection allows the hot gas to be maintained quasi-isothermally throughout the system at the highest temperature permitted by the energy conversion cycles, and by the limit imposed by the formation of nitrogen oxide pollutants in the exhaust, thereby allowing maximum efficiency and minimum size and cost of the energy conversion system. Use of air injection into the hot fuel gas, as compared with the conventional injection of fuel into a hot oxidizing gas, permits maintaining a highly reducing atmosphere throughout most of the energy conversion process. This greatly reduces the quantity of nitrogen oxides formed at a given gas temperature and permits the use of superior high temperature materials which cannot be used in an oxidizing atmosphere. It should be recognized that the hot off gas from the takeoff pipe 52 (or its equivalent in other embodiments of the present specification) is used substantially better directly in a staged combustion process.

The ratio of the heating value H R of hot off gas to the heating value, H O of gas at the same temperature obtained by burning colder off gas is

$\frac{\mathrm{Hr}}{\mathrm{Ho}}=\left(1+\mathrm{CdT}/Q\right)+\left(1+5/6\times \mathrm{CdT}/Q\right)$

where C is the specific heat of the gases, Q is their heat of combustion per pound and dT is the difference between off gas temperature of the two different gasifiers.

The first bracketed term arises from the additional sensible heat in the hotter off gas. The second bracketed term arises from the additional volume of nitrogen mixed with the colder gas during its combustion with air to the higher temperature. What results then is a staged combustion-energy abstraction apparatus referred to generally as an energy extractor 16, which energy extractor is operated directly by reactor 14 wherein a liquid 34 dissolves carbon introduced from the digestor 12 and reacts that carbon with an oxidizing means introduced into the oxidation chamber means 44 to produce a hot gas, generally a hot fuel gas.

Since the feed 18 introduced into the digestor 12 and eventually introduced in the form of the mass 24 into the reactor 14 will generally contain a number of materials besides carbon, it is clear that an impurity slag layer 66 will be formed upon the surface 68 of the liquid 34 and thereby be separated from the carbon and the valuable volatile chemicals. A slag tap 70 is thus preferably provided which serves as a means for removing the impurity slag layer 66 formed in the carbonization chamber 42. It is further noted that since the impurity slag layer 66 is maintained only within the carbonization chamber 42, as a result of the separation provided by the baffle means 40, there is substantially no impurity slag layer within the oxidation chamber means 44 and hence the oxidizing means, usually oxidation gas means, introduced into the oxidation chamber means 44 can be maintained in efficient close contact with the liquid 34 therein, leading to a high rate of oxygen reaction therewith in the liquid 34, and an absence of fly ash in the hot gas exhaust evolved therefrom. The impurity slag layer 66 as removed by the slag tap 70 can then be used to produce by-products such as bricks, insulation material and the like.

It will be noted that when an oxidizing gas is used with a high free oxygen content, the reactor 14 may include means for skull cooling whereby the liquid 34 is within a vessel made of solidified liquid 34. Thus, a plurality of skull cooling pipes 72 are provided within the walls of the reactor 14. As cooling fluid (e.g., preheat oxidizing gas) is passed through the skull cooling pipes 72, the liquid 34 is cooled to below its melting point thereadjacent, thus forming a solid layer of solidified liquid 34 which serves as a non-corroding vessel for the liquid 34.

It will be noted that in the embodiment illustrated in FIG. 1, the dissolved carbon within the liquid 34 is circulated underneath the baffle means 40 to the oxidation means chamber 44 and therein reacts with the iron oxide dissolved in the liquid 34 in said oxidation chamber means 44 to form carbon monoxide which is quite insoluble in, for example, molten liquid iron. The carbon monoxide thus forms a part of the hot gas which passes up the takeoff pipe 52. Another part of the hot gas which passes up the takeup pipe 52 is formed, for example, from the air which is injected thereinto.

The oxygen of the air, as previously mentioned, reacts with the iron to form iron oxide which is thereby bound (chemically or physically) to the liquid 34. This oxygen later becomes carbon monoxide through reaction with the dissolved carbon as just explained. The nitrogen, argon and the like in the air, however, is not reactive under the conditions in the reactor 14 with the iron and is simply heated within the reactor 14 and forms a part of the first hot gas which passes up the takeoff pipe 52. Similarly, if steam is injected along with air, the oxygen is abstracted therefrom by the iron to form iron oxide with the concurrent production of hydrogen and with the hydrogen then forming a part of the gas which passes up the takeoff pipe 52. Thus, that which is being converted to energy in the energy extractor 16 would comprise a mixture of nitrogen gas, hydrogen gas, and carbon monoxide along with various impurity gases and perhaps some reaction gases of these.

DESCRIPTION OF OTHER EMBODIMENTS

Example 2

Referring now particularly to FIG. 2, there is illustrated therein a known embodiment implemented according to the present specification wherein the baffle means 40 defines in addition to the carbonization chamber 42 and the oxidation chamber means 44, a leaching chamber 74 for sulfur removal. The baffle means 40 serves to separate the leaching chamber 74 above the liquid level 36 from the carbonization chamber 42 and the oxidation chamber means 44, but allows flow of the liquid 34, for example, under the influence of mechanical stirrers 75, into the leaching chamber 74 from the carburization chamber 42 and out of the leaching chamber 74 and into the oxidation chamber means 44. Thus, liquid 34 which has both carbon and sulfur dissolved therein can enter the leaching chamber 74 via entrance means 76 and can leave the leaching chamber 74 via exit means 78 and can enter the oxidation chamber means 44 via oxidation entrance means 79.

A high basicity mixture of metal oxides is maintained in the leaching chamber 74 as a leach slag 82 floating on the surface of the liquid 34. The leach slag 82 may include any of a number of alkali metal and/or alkaline earth oxides but will be spoken of as predominantly a calcium oxide slag for illustration purposes and because calcium oxide is readily available and will work extremely well in the desulfurization reaction, reacts with the dissolved sulfur to form calcium sulfide and a gas comprising carbon monoxide. The purpose of the chemically non-active components of the leach slag 82 is to lower its melting point and thereby allow the leach slag to be maintained in a molten state at the temperature of the liquid 34 to ensure intimate and complete contact between the slag 82 and liquid 34.

An example of a suitable slag if the liquid 34 is molten iron at 1500° C. would be the mixture 50% by weight CaO, 7% Al2O3 and 43% SiO2. The leach slag 82, which includes the calcium sulfide formed within the leaching chamber 74, is substantially insoluable in the liquid 34, which liquid 34 is generally molten iron and forms the separate molten leach slag layer 82 which floats upon the liquid 34 within the leaching chamber 74. A leach slag tap 84 is provided for removal of the leach slag. The leach slag 82 may be conducted from the tap 84 to a conventional desulfurizer 86 wherein its calcium sulfide content is reacted with steam and carbon dioxide to form sulfur which is removed and the regenerated leach slag 82 may be recycled into leaching chamber 74. Such regeneration and recycled is usable with all embodiments of the present specification.

It is seen that the oxidation chamber means 44 can be divided in the embodiment illustrated in FIG. 2 into a decarbonization chamber 94 and a first oxidation chamber 96. This can be accomplished by extending the baffle means 40 to include means for separating the oxidation means 44 within the reactor 14 above the liquid level 36 from both the carbonization chamber 42 and the first oxidation chamber 96, and, when such is provided, from the leaching chamber 74.

With such a structure, the oxidizing gas means, for example, air, is introduced into the first oxidation chamber 96 via one or more of the plurality of conduits 48 wherein it reacts with the molten liquid 34 to provide oxygen bound therein, for example, iron oxide, and to further provide nitrogen as a hot gas which can exit therefrom as via a first oxidation chamber outlet pipe 98. A first oxidation chamber-to-decarbonization chamber passage 100 is provided to allow the circulation of oxygen rich liquid 34 into the decarbonization chamber 94, wherein it reacts with carbon dissolved in the liquid 34 to form carbon monoxide which then exits the decarbonization chamber 94 via a decarbonzation chamber outlet pipe 102.

The concentration of oxygen introduced into the decarbonization chamber 94 should be sufficient so that when the liquid 34 is returned to the first oxidation chamber 96, the return liquid 34 is substantially free of carbon. Flow from the decarbonization chamber 94 to the carbonization chamber 42, consisting of the combined flows through entrance means 76, contains sufficient excess carbon to ensure that the liquid 34 which returns to the carbonization chamber 42 to be substantially free of oxygen.

This ensures that a substantial amount of CO is not released in either the carbonization or first oxidation chambers. The hot gas which passes out of the first oxidation chamber outlet pipe 98 is substantially nitrogen, and if steam is introduced, hydrogen. Thus, in the embodiment illustrated in the FIG. 2, the reactor 14 serves to provide at least somewhat purified gases, namely, carbon monoxide and nitrogen which gases can have significant value in industrial processes and which gases can have the energy therefrom extracted either in a single energy extractor 16 by combining the gases or separately in a plurality of energy extractors 16, it is seen that oxidation chamber means 44 can be divided into not only the decarbonization chamber 94 and the first oxidation chamber 96, but also into a second oxidation chamber 108 into which steam is injected via conduits 109 and from which hydrogen is obtained in a fairly pure form from a second oxidation chamber outlet pipe 110.

Example 3

It is an object of this known example to provide an improved process for generating a low BTU gas from carbonaceous material. It is yet another object of the present specification to provide a process for heat generation from carbonaceous materials which obviates removal of pollutants formed in the combustion reaction. A particular object of the present specification is the provision of a process for partial oxidation of a carbonaceous material in a molten alkali metal salt medium for production of a gaseous effluent containing a high proportion of combustible gases, particularly carbon monoxide and hydrogen, such gaseous effluent then being adapted for further and complete combustion in a secondary reaction zone or combustor, to utilize the heat value of the gas.

In accordance with the broad aspects of the present specification, a carbonaceous material such as coal or a combustible waste material is introduced, together with a source of oxygen, suitably and preferably air, into a reaction zone preferably maintained at above atmospheric pressure. Pressures from 1 to about 20 atmospheres are preferred, pressures between 5 to 10 atmospheres being particularly preferred. This reaction zone contains a molten salt mixture consisting essentially either only of an alkali metal carbonate or mixture of alkali metal carbonates, or preferably consisting essentially of a major portion of an alkali metal carbonate and a minor portion of an alkali metal sulfate or sulfide. The source of oxygen, preferably air, is employed in a proportion such as to provide an amount of oxygen substantially below the amount stoichiometrically required for complete combustion of the carbonaceous material. Generally the air employed is used in a proportion to provide less than about 60 percent of the amount of oxygen stoichiometrically required for complete oxidation or combustion. Other reaction parameters are controlled so as to favor incomplete combustion of the carbonaceous material, and maximize production of CO, consistent with maintenance of the molten salt temperature at a pre-determined value, as well as adequate throughput of coal or carbonaceous material in the most economical manner.

It is particularly preferred that at least 1 wt. percent of alkali metal sulfide, and up to 25 wt. percent, be present in the molten salt under steady-state conditions, the sulfide serving to catalyze the rate of partial combustion of the carbonaceous material. Any sulfate initially present is converted to sulfide under steady-state conditions. In addition to the direct addition of sulfide to the melt, coal or other carbonaceous material containing sulfur can also serve as a source of the sulfide. The temperature of the molten salt is maintained between about 1400° and about 2000° F. (about 760° to 1100° C.), particularly between about 1,600° and about 1,800° F. (about 870°-980° C.) where coal is the carbonaceous material. The result is a gaseous effluent from the gasification and combustion reactions which contains a substantially greater volume of CO than CO 2, generally at least 5:1 and up to 20:1, and which also contains other combustible gases such as hydrogen and hydrocarbons.

The sulfur and sulfur-bearing contaminants and ash present in the carbonaceous material or fuel, e.g., coal, are retained in the molten salt. The retention of the sulfur and ash from the fuel in the melt eliminates the requirement for a stack gas sulfur oxide removal system and an electrostatic precipitator. These materials can be removed from the reaction zone with a continuous stream of molten salt, the contaminants removed from such stream, and the regenerated stream of molten salt being returned to the reactor. Nitrogen oxide formation is negligible at the relatively low temperatures prevailing in the molten salt furnace.

The resulting combustible gaseous effluent from the salt furnace containing a substantial portion of combustible gases such as carbon monoxide and hydrogen can then be brought into a second combustion zone or unit, which may be in the form of a conventional utility boiler, and reacted therein with oxygen of the air to oxidize the combustible gases to CO2 and water with the release of heat.

With reference to FIG. 3, a reactor vessel 100 implemented according to the present specification, contains a body of molten salt 102, e.g. comprising sodium carbonate and 1 to 15 wt. percent sodium sulfide. The reactor is provided with an insulated air or water cooling jacket 104, and there is provided a primary air inlet 106 and an air manifold distributor system 108, and coal inlets 110, the air manifold and coal inlets being interconnected. The coal inlets can also serve for introduction of alkali metal carbonate into the reactor. The reactor is also provided with a melt outlet 112 and a gaseous outlet 114. The outlet 114 is provided with a conventional demister 116 for removing liquid and solid particulates from the effluent gas. The reactor is also provided in the interior thereof with an overflow weir 118, to maintain a constant level of molten salt, and a drain 120. Air is supplied to the reaction or partial oxidation zone 122 comprised of the salt melt 102 through the air distributor system 108.

In the molten salt furnace, the carbonaceous material is partially combusted to CO, CO2 and H2O, with release of hydrogen and hydrocarbons into the resulting gases. The partial combustion and the gasification take place rapidly at relatively low temperatures, e.g. of the order of 1,700°-1,800° F., because of the high contact areas and high heat transfer rates, and more importantly, because of the catalytic effect of the sodium sulfide dissolved in the melt.

Under the conditions of reaction according to the present specification, employing a proportion of air to provide less than about 60 percent of the amount of oxygen stoichiometrically required for complete oxidation of the carbonaceous material, preferably about 35 to about 45 percent of such stoichiometric amount, partial oxidation of the coal occurs in the molten salt reaction zone 102. The gaseous effluent exiting the reactor at 114 contains at least 5 to 1 volumetric ratio of carbon monoxide to carbon dioxide, together with hydrogen, hydrocarbons and water, and also nitrogen from the air supply.

As the reaction proceeds in the molten salt body 102, acidic contaminants such as sulfur or sulfur-bearing materials in the carbonaceous material or coal pass into the molten salt, the sulfur-bearing materials forming alkali metal sulfides such as sodium sulfide. The capacity of the salt melt for retaining the sulfur and ash of the coal is limited by the maximum allowable concentration of these materials in the melt. When this concentration is reached, any undesirable buildup of sulfur and ash in the melt is prevented, and a steady-state condition is established by continuous withdrawal of the side stream 112 of sulfur- and ash-containing melt and addition of regenerated sodium carbonate and carbonate makeup back into the molten salt furnace.

This side stream is quenched in water, which dissolves the sodium carbonate and sulfur compounds. The insoluble ash and any uncombusted carbon are removed from the solution by clarification and/or filtration, preferably in the presence of CO 2 to decrease silicate formation. Carbonation of the filtrate with flue gas and steam stripping are employed to regenerate the sodium carbonate and release hydrogen sulfide. The hydrogen sulfide is processed in a conventional manner for recovery of elemental sulfur or sulfuric acid. The sodium carbonate is crystallized out of its water solution, and after addition of makeup, is returned to the molten salt furnace.

Although the combustion of the combustible gaseous product from reactor 102 has been described above the drawing as being further combusted in a separate combustor or burner 18, it will be understood that such combustible gaseous product may be combusted, e.g., in the reactor vessel, in a zone above the body of the melt 102.

As a further feature, integration of the molten salt combustion and gasification process of the present specification into a conventional coal-fired steam plant can be achieved by incorporating the molten salt furnace and its associated auxiliary equipment into the coal feed system of the boiler. The molten salt furnace can thus be considered as an additional initial step in the treatment of the coal prior to combustion of the product gas in the boiler. The integration of the molten salt furnace system into a conventional power plant can be done in various ways, the simplest involving the installation of the molten salt furnace as a supplementary unit upstream of the boiler.

Operation of the molten salt furnace at a pressure just high enough above ambient to allow injection of the gas generated into the boiler, as in conventional operation, has the disadvantage that it requires a large cross section molten salt furnace, since the controlling parameter involved is the superficial velocity of the fuel gas generated. To decrease the cross section of the molten salt furnace, operation of this furnace can be carried out under pressure. Typically a pressure of 5 atmospheres will decrease the diameter of the furnace by a factor of 2.2. The amount of energy required to compress the primary air feed is however appreciable and, for economic reasons, it is important that this energy be recovered by expanding either the fuel gas produced or the off-gas from the system through a gas turbine.

Example 4

In this embodiment of a known bath gasifier configuration implemented according to the present specification, there is provided an apparatus for gasification of carbon (C) in the form of carbon, hydrocarbons and/or hydrocarbon compounds, comprising a reactor in which injection of carbon, oxygen gas and iron oxides takes place under the surface of the iron melt, and in which carbon is injected in stoichiometric excess in relation to the amount of oxygen in the form of oxide compounds in the melt, the reactor having a total inner pressure exceeding atmospheric pressure. The present specification is further characterized in that an exhaust gas pipe from the reactor is closely attached to a cooling device, which together with the reactor forms a sealed unit and in that a regulating valve for controlling and maintaining overpressure in the said unit is placed on the cold side of the cooling device.

FIG. 4 shows a reactor 1, lined and provided with a steel mantle, which during operation contains a crude iron melt 2. In FIG. 4, the reference number 3 refers to slag floating on top of the crude iron melt. The reactor 1 is preferably designed to be tilted round an axis 4 for discharge of crude iron 2 through opening 5. This can be seen best in FIG. 10.

Carbon, iron-ore concentrate, oxygen and slag-forming compounds are injected by means of conventional lances and/or injection pipes.

In the top of the reactor 1 there is an exhaust gas pipe 6 for the gas produced, which is connected by a gas-tight coupling 7 to a device in the direction in which the gas is transported. This device comprises a cooler, generally represented by 8, which according to this embodiment comprises two conventional steam boilers 9,10. According to a preferred embodiment the cooler contains a dust separator.

The gas produced is thus led through the pipe 6 and another pipe 11 to the first boiler 9. The gas is then led to the second of the two boilers, 10, and on to a discharge pipe 12. The discharge pipe is provided with a regulating valve 13 for controlling and maintaining the pressure in the reactor and the cooler 8. The regulating valve 13 is of any suitable kind.

As the gas in the outlet pipe 12 has a considerably lower temperature than before it reaches the cooler, e.g. a temperature of approximately 200° C. (392° F.) a quite conventional regulating valve and conventional pressure units may be used. It is thus possible to avoid the considerable difficulties that would arise if the pressure had to be adjusted on the hot side, i.e. in direct connection with the exhaust gas pipe 6 from the reactor, where the temperature of the exhaust gas is approximately 1300° C. to 1400° C. (2372° F. to 2552° F.).

As the pressure is adjusted after the cooler 8, this cooler is maintained under pressure and is thus designed to resist any increased pressure in the system. Dust that has been separated is discharged through valves 14,15 at the bottom of the dust separators 16,17.

As mentioned above it is desirable to be able to tap off slag 3 during operation, i.e. whilst the reactor 1 is pressurized. According to the present specification there is a device for tapping slag for this purpose, which is also pressurized at a pressure corresponding to the pressure in the reactor. The device for tapping slag comprises a horizontal slag channel 18 at the same level as a pre-determined slag height, leading to a descending slag channel 19. The channel 19 is connected to a granulator 20.

In the horizontal channel 18 there is a flooding valve comprising a stone 21 or a board of a suitable material which in its lower end position closes the slag channel between the reactor and the granulator 20 (See FIG. 8) and which in its raised position opens the channel mentioned. The stone 21 is sealed to the walls of the slag channel by means of devices not shown. A sealed housing 22 which is marked with dashes in FIG. 8 is placed, according to one embodiment, above the stone 21. This housing may also comprise a control, not shown, for positioning the stone 21. When the level of the slag in the reactor reaches the level of the horizontal slag channel 18, the stone 21 will be pushed upwards and slag will run out of the reactor 1 down to the granulator 20. In order to equalize the pressure in the granulator 20 both at this stage and when granulated material is discharged through a valve 23 at the bottom of the granulator, a pressure equalizing pipe 24 which includes a regulating valve 25 is provided.

This pipe 24 connects the granulator 20 with the above-mentioned pipe 11, which leads gas away from the reactor 1. With wet granulation, hydrogen sulfide (H2S) is formed which is allowed to leave the granulator through a pipe 26. This pipe 26 is also provided with a regulating valve 27 for maintaining pressure in the granulator 20. In order to enable discharge of crude iron during operation there is a channel 18′,19′ which corresponds to the above-mentioned channel 18,19 and which connects the reactor with a second granulator 20′ for granulation of crude iron. This channel 18′ is also provided with a flooding valve in the form of a stone 21′ or a board which operates in the same way as the previously mentioned flooding valve 21. This second granulator 20′ is pressurized and connected to said further pipe 11 by a pressure equalizing pipe 24′. A pipe 26′ and a regulating valve 27′ are also provided for discharging the gases produced to the atmosphere.

The horizontal channels 18,18′ and the stones 21,21′ are fitted in or adjacent to the wall of the reactor 1. Thus a very high temperature will prevail at the stones 21,21′, which will eliminate freezing and blockage by slag and/or crude iron splashes. The pressurizing of the granulators 20,20′ slag and crude iron can be discharged continuously or intermittently during operation. Further it is not necessary for the stones 21,21′ to be designed to deal with pressure differences between the horizontal channels 18,18′ and the descending channels 19,19′. In one embodiment, the channels 18,18′ are arranged parallel to each other. In FIG. 6 the channels 18,18′ are shown positioned at the same level. The height of the channels 18,18′ may, of course, be varied according to the pre-determined slag level and the thickness of the slag layer. In such a case the channel 18′ for tapping crude iron is preferably positioned at a lower level than a channel 18 for tapping slag. The descending channels 19,19′ are each provided with a sealed coupling 28,28′. When all the crude iron is to be discharged, these couplings 28,28′ are released as well as the coupling 7 on the exhaust gas pipe 6 on the reactor and the reactor is then tilted.

Gasification reactor and refractory vessel assembly example:

In one example the gasification reactor comprises a refractory-lined vessel that is of a substantially cylindrical geometry to hold a molten metal mass, also called a melt, and an induction coil apparatus and related supporting structure for holding the refractory-lined vessel, the induction coil apparatus in operational communication with the gasification reactor.

The refractory-lined vessel is positioned and tilted about its horizontal plane so as to cause the refractory-lined vessel to be tilted at a pre-determined tilt angle to further direct the flow of molten slag material that will be formed on the top layer of the melt during gasification of the feed into product syngas.

The tilt angle α as shown in FIG. 9, may be determined prior to gasification conversion of the feed into product syngas, and is determined within the range of 0-60 degrees, alternatively, this may also be described in angular unit of measure radians (or rad).

For instance, if the determined tilt angle of the refractory-lined vessel is 45 degrees, the determined tilt angle is approximately 0.7853 rad.

The horizontal plane as shown in the imaginary dotted line in FIG. 9, therefore, the refractory-lined vessel will be positioned and tilted about its horizontal plane as shown at a determined tilt angle α, so as to allow for the removal of molten slag that is formed on the top layer of the melt disposed within the refractory-lined vessel during gasification operations of the present specification and conversion of the feed that is placed into contact with the melt to generate product syngas.

The refractory-lined vessel is further adapted with a cover lid device that is operationally configured with the top of the refractory-lined vessel to be substantially gas tight, and or causing the refractory-lined vessel to be substantially gas tight, the cover lid device further adapted with at least one inlet port to facilitate the flow of carbonaceous material, or feed, into contact with the melt contained in the refractory-lined vessel.

The inlet port may be operationally configured with a tubular apparatus such as a feed lance, or said feed lance and or tubular apparatus is in fluid communication with the inlet port so as to perform the facilitation, transport and flow of feed into contact with the melt that is contained within the refractory-lined vessel.

Further, the cover lid device is operationally configured with at least one outlet port that is in fluid communication with at least one tubular outlet conduit device for directing the flow of product syngas and or raw syngas evolving from the melt to either a powerplant (such as a reciprocating engine unit, a gas turbine, or a fuel cell electricity-generating system), a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof.

FIGS. 6 to 8 show further views of the gasification system of FIG. 4, wherein FIG. 6 shows a partial view comprising a vessel of the gasifier system of FIG. 4, FIG. 7 shows a first cross section of the vessel of FIG. 6, FIG. 8 shows a second cross section of the vessel of FIG. 6 which is perpendicular to the first cross section. FIG. 9 illustrates tilting angles of a reactor vessel according to the present specification, FIG. 10 shows a tilted reactor vessel according to the present specification. The tilting mechanism shown in FIG. 9, 10 can be used in combination with all types of reactors according to the specification and in particular with the reactor vessels of FIG. 4, FIG. 12, and FIG. 13.

FIGS. 11 to 13 show views of further molten metal gasification systems. FIG. 11 shows an ash removal section of a molten metal gasification system according to a further embodiment, which can be used together with the reactor vessels shown in the present specification.

FIG. 12 shows a molten metal gasification system according to a further embodiment, and FIG. 13 shows a molten metal gasification system according to a yet a further embodiment.

A gasifier 200 according to FIG. 13 comprises a first reactor vessel 201 that is covered by a cover 202. The gasifier 200 is connected to a second reactor vessel 203 via a gas passage conduit 204. In a further embodiment, the gasifier is connected to an electric power plant 203.

The reactor vessel 201 contains a molten metal layer 207 and a molten slag-oxyde layer 208 which floats on top of the molten metal layer 207.

The gasifier 200 comprises injection tubes 205, 206 for injecting air jets into the molten slag-oxyde layer 208 and through the slag-oxyde layer 208 into the molten metal layer 107. Furthermore, an overhead lance 216 is provided in the cover 202 and feed conduits 209, 210 are provided in a bottom wall of the reactor vessel 201. In other embodiments, further feed conduits may be provided in side walls of the reactor vessel 201. The overhead lance 216 provides an example of a tubular conduit according to the specification.

The injection tubes 205, 206 are connected to an air reservoir 211 via a compressor 212. The overhead lance 216 is connected to a reservoir 213 of a feed fuel via a feeder pump 214. A tilting mechanism 215 is provided for tilting the first reactor vessel 201 at a tilt angle alpha. In one embodiment, the tilt angle can be adjusted between 0 and 60 degrees.

A retractable measuring lance 217 is provided at right angles to a side wall of the vessel. The measuring lance 217 comprises a measurement opening and a temperature sensor. In yet another embodiment, a measuring lance is provided which is configured to sample material from the slag layer or the molten metal layer.

In a first aspect, the present specification discloses a method to perform gasification in a gasification reactor having a molten metal material disposed within a gasification reactor for converting a feed into product syngas by contacting feed into melt. The gasification reactor comprises a refractory-lined vessel in operational communication with gasification reactor for holding melt.

A melt is formed by inductive melting by one or more induction coil apparatuses energized with one or more alternating current “AC” power waveforms. In other words, if there is more than one induction coil the individual induction coils may be powered by AC current of different frequencies and/or different waveform shapes.

A feed is injected into contact with the melt to dissolve at least a portion of the feed into the melt, wherein the feed is selected from coal, lignite, coal-liquid slurry, wood, biomass, municipal solid waste, sewage, crude oil, natural gas, petroleum residue, bituminous sand, seawater, shale oil material, peat, or a combination thereof.

The refractory-lined vessel is tilted and positioned at a pre-determined tilt angle about a horizontal plane to cause the refractory-lined vessel to be tilted at said pre-determined tilt angle from said horizontal plane during a conversion of the feed into a product syngas.

A molten slag material, which is formed during conversion of the feed into product syngas, is directed to flow away from the refractory-lined vessel at a pre-determined molten slag material flow rate.

The product syngas is directed to flow from the refractory-lined vessel to a powerplant for electric power generation, a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof.

By tilting the reaction vessel according to the application, the slag layer can be adjusted to a pre-determined height. Furthermore, the material composition of the slag layer can be adjusted. Thereby, the conversion process of a feed into a product gas, such as syngas can be adjusted by using a gasification method according to the present specification.

A travel length of air, oxygen and feed through the slag layer can be controlled. It turned out that this is useful when controlling the gasification process, for instance for adjusting a pre-warming temperature of the respective streams in the slag before penetrating the slag and reaching the molten metal underneath the slag.

In a second aspect, the present specification discloses a gasification reactor for converting a feed into product syngas by contacting the feed into a melt which is disposed within the gasification reactor.

The gasification reactor comprises an induction coil apparatus for inductively heating the melt during a conversion of the feed into product syngas. The induction coil apparatus is arranged in proximity to a refractory-lined vessel which is in operational communication with the gasification reactor and which is provided for holding the melt.

An injection means such as an overhead lance or any other type of feed conduit is provided for injecting a feed into contact with the melt to dissolve at least a portion of the feed into the melt. The feed may be transported by various means such as a pump, a conveyer belt or a disperser and a compressor. The feed may also be mixed with gases, additives or other material. The feed may be comprises liquid, solid or gaseous components and it may also be dispersed in fine form.

The gasification reactor further comprises a tilting and positioning means for tilting and positioning the refractory-lined vessel at a pre-determined tilt angle about a horizontal plane to cause the refractory-lined vessel to be tilted at the pre-determined tilt angle with respect to the horizontal plane during a conversion of the feed into a product syngas.

Moreover, the gasification reactor comprises a slag conduit for directing molten slag material formed during conversion of the feed into product syngas to flow away from the refractory-lined vessel at a pre-determined molten slag material flow rate.

A gas conduit, also known as downstream application conduit, is provided for directing product syngas to flow from the refractory-lined vessel to a syngas processing apparatus. By way of example, the syngas processing apparatus may be provided by a powerplant for electric power generation, a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof.

In a further embodiment, the vessel of the gasification reactor is equipped with a sensing lance which comprises a sensor, wherein the sensor is connected to a processor for evaluating signals of the sensor. In one embodiment, the sensor is provided as temperature sensor for measuring a temperature of a syngas stream. The measuring lance may be retractable such that the measuring lance can be moved to a suitable position when a measurement is performed and can be moved out of the way when no measurement is performed. According to the present specification, the measurement values of the sensor can be used to control the supply of the first vessel with feed, additives and gases, or to determine a suitable time and/or a suitable tilting angle for tilting the first vessel and removing slag or it can also be used to control a syngas processing in further reactor vessels which are connected to a gas conduit of the first vessel, for example by adjusting an amount of supplied water to the syngas processing.

In one particular embodiment, the sensor is configured within a designated interior wall surface of the gasifier to receive a flow-stream of hot gasified product syngas evolving from the gasifier. The sensor is furthermore configured to perform a multiplicity of measurements over a pre-determined time period to derive a plurality of data signals indicative of said multiplicity of measurements over the pre-determined time period;

The sensor further comprises—or is connected to—a processor controller which is configured to receive the derived plurality of data signals and to perform at least one algorithmic calculation to determine a proximate temperature of said flow-stream of the hot gasified product syngas within the pre-determined time period as sensed by the sensor.

The same sensor or a further sensor is configured to generate a control signal indicative of a proximate temperature addressed to a feedwater flow control valve pump so as to regulate and control the fluid flow of feedwater flowing in a steam generator device in fluid communication with the flow-stream of hot gasified product syngas.

It is to be understood that the foregoing detailed description is given merely by way of illustration and that many variations can be made therein without departing from the spirit or scope of this specification.

The embodiments of the present specification can also be described with the following lists of elements being organized into items. The respective combinations of features which are disclosed in the item list are regarded as independent subject matter, respectively, that can also be combined with other features of the application.

• 1. A method and apparatus for conducting gasification of a feed into product syngas utilizing a gasifier, comprising:
  • a sensor configured within a designated interior wall surface of the gasifier to receive a flow-stream of a hot gasified product syngas evolving from the gasifier; and
  • the sensor performing a multiplicity of measurements over a pre-determined time period to derive a plurality of data signals indicative of said multiplicity of measurements over the pre-determined time period;
  • wherein;
  • the sensor further comprises a processor controller to receive derived plurality of data signals and performing at least one algorithmic calculation to determine the proximate temperature of said flow-stream of hot gasified product syngas within the said determined time period as sensed by the sensor; and
  • the processor controller being configured to generate a control signal indicative of the pre-determined proximate temperature addressed to a feedwater flow control valve pump so as to regulate and control the fluid flow of feedwater flowing in a steam generator device in fluid communication with the flow-stream of hot gasified product syngas.
• 2. The method and apparatus of item 1 wherein the processor controller is further configured to retrieve from an electronic memory a default control signal indicative of a reference feedwater fluid flow rate, addressed to the feedwater flow control valve pump to regulate and control the fluid flow of feedwater flowing in the steam generator device according to the indicative reference feedwater fluid flow rate, in the event where the processor controller is unable to generate a proximate temperature from said received derived plurality of data signals.
• 3. The method and apparatus of item 1 or item 2, wherein product syngas flowing through from steam generator device is directed by one or more gas passage conduit to a powerplant for electric power generation, a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof.
• 4. The method and apparatus of one of the items 1 to 3, wherein the feed is selected from coal, lignite, coal-liquid slurry, wood, biomass, municipal solid waste, sewage, crude oil, natural gas, petroleum residue, bituminous sand, seawater, shale oil material, peat, or a combination thereof.
• 5. A method and apparatus for conducting gasification of a feed into product syngas utilizing a gasifier, comprising:
  • a sensor configured within a designated interior wall surface of the said gasifier to receive a flow-stream of hot gasified product syngas evolving from the gasifier; and
  • sensor performing a multiplicity of measurements over a pre-determined time period to derive a plurality of data signals indicative of said multiplicity of measurements over said determined time period;
  • wherein;
  • the sensor further comprises a processor controller to receive a derived plurality of data signals and performing at least one algorithmic calculation to determine a proximate temperature of said flow-stream of hot gasified product syngas within the pre-determined time period as sensed by the sensor; and
  • the processor controller being configured to generate a control signal indicative of a proximate temperature addressed to a feedwater flow control valve pump so as to regulate and control the fluid flow of feedwater flowing in a steam generator device in fluid communication with said flow-stream of hot gasified product syngas.
• 6. The method and apparatus of item 5 wherein the processor controller is further configured to retrieve from an electronic memory a default control signal indicative of a reference feedwater fluid flow rate, addressed to the feedwater flow control valve pump to regulate and control the fluid flow of feedwater flowing in the steam generator device according to the indicative reference feedwater fluid flow rate, in the event where the processor controller is unable to generate a proximate temperature from said received derived plurality of data signals.
• 7. The method and apparatus of item 5 or item 6 wherein the sensor is configured within said designated interior wall surface where the superficial gas velocity of said flow-stream of hot gasified product syngas evolving from the gasifier is at least about 2 meters per second.
• 8. The method and apparatus of one of the items 5 to 7 wherein the sensor is configured to be protruding a proximate distance of at least 1 inch from the surface of the designated wall surface.
• 9. The method and apparatus of one of the items 5 to 7 further comprising a sensor having an extendable member tubular body to travel on a perpendicular axis plane to the designated wall surface axis plane between a proximate distance of 1 inch to 8.5 inches.
• 10. The method and apparatus of item 9, wherein the perpendicular axis plane to which said extendable member tubular body to travel said proximate distance is denoted axis line AB.
• 11. The method and apparatus of item 9 wherein designated wall surface axis plane is denoted axis line CD and said extendable member tubular body travels on said perpendicular axis plane AB⊥CD.
• 12. The method and apparatus of one of the items 5 to 11, wherein product syngas flowing through from a steam generator device is directed by one or more gas passage conduits to a powerplant for electric power generation, a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof.
• 13. The method and apparatus of item 12 wherein the product syngas flowing through from steam generator device has a superficial gas velocity of at least 0.3 meters per second.
• 14. The method and apparatus of one of the items 5 to 13 wherein the feed is selected from coal, lignite, coal-liquid slurry, wood, biomass, municipal solid waste, sewage, crude oil, natural gas, petroleum residue, bituminous sand, seawater, shale oil material, peat, or a combination thereof.
• 15. The method and apparatus of one of the items 5 to 14, further comprising operating the gasifier under gasifiying conditions during said gasification of the feed into product syngas wherein the temperature of the said gasifier under said gasifying conditions is at least 925 degrees C.
• 16. The method and apparatus of one of the items 1 to 14, wherein an oxygen-carrying gas is directed into the gasifier during gasification of the feed at a superficial gas velocity of at least about 10 meters per second.
• 17. The method and apparatus of item 16 wherein the oxygen-carrying gas is selected from air, oxygen, carbon dioxide, or a combination thereof.
• 18. A method for conducting gasification of a feed into product syngas in a gasifier having a melt disposed within said gasifier, comprising injecting the feed into contact with the melt to dissolve at least a portion of the feed into the melt and further directing a stream of oxygen-carrying gas into contact with the melt from below the surface of the said melt at a superficial gas velocity of at least 10 meters per second to partially oxidize the melt to generate product syngas, further directing product syngas to flow through a steam generator device to transfer heat from said product syngas to steam generator device to cause generation of steam.
• 19. The method of item 18 comprising directing product syngas to flow through from a steam generator device at a superficial gas velocity of at least 0.3 meters per second.
• 20. The method of item 18 or item 19 wherein the melt disposed within the gasifier is heated to a temperature of at least 1300 degrees C.
• 21. The method of one of the items 18 to 20, wherein feed is selected from coal, lignite, coal-liquid slurry, wood, biomass, municipal solid waste, sewage, crude oil, natural gas, petroleum residue, bituminous sand, seawater, shale oil material, peat, or a combination thereof.
• 22. The method of one of the items 18 to 21, wherein the oxygen-carrying gas is selected from air, oxygen, carbon dioxide, or a combination thereof.
• 23. The method of one of the items 18 to 22, wherein the product syngas is directed to flow from steam generator device to a powerplant for electric power generation, a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof.
• 24. In a gasification reactor having a melt disposed within the gasification reactor for converting a feed into product syngas by contacting feed into melt and a induction coil apparatus for inductively heating melt during conversion of said feed into product syngas, the gasification reactor comprises:
  • a refractory-lined vessel in operational communication with said gasification reactor for holding said melt; and
  • wherein the refractory-lined vessel is tilted at a determined tilt angle about a horizontal plane so as to allow a layer of molten slag formed and residing on the top layer of melt during said conversion of the feed into product syngas to flow away from refractory-lined vessel.
• 25. The gasification reactor of item 24 wherein the product syngas is directed to flow from the refractory-lined vessel to a powerplant for electric power generation, a first chemical catalytic reactor to chemically reform product syngas into a pre-determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof.
• 26. In a gasification reactor having a melt disposed within the gasification reactor for converting a feed into product syngas by contacting the feed into melt and a gas injection apparatus for contacting an oxygen-containing gas into melt to cause exothermic heating of said melt during conversion of said feed into product syngas, wherein the gasification reactor comprises:
  • a refractory-lined vessel in operational communication with the gasification reactor for holding said melt; and
  • wherein the refractory-lined vessel is tilted at a pre-determined tilt angle about a horizontal plane so as to allow a layer of molten slag formed during said conversion of the feed into product syngas to flow away from refractory-lined vessel.
• 27. The gasification reactor of item 26 wherein the product syngas is directed to flow from the refractory-lined vessel to a powerplant for electric power generation, a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof.
• 28. The gasification reactor of item 26 or item 27, wherein the oxygen-carrying gas is selected from air, steam, oxygen, oxygen-enriched oxygen, carbon dioxide, or a combination thereof.
• 29. In a gasification reactor having a melt disposed within gasification reactor for converting a feed into product syngas by contacting the feed into melt, the temperature of said melt is inductively heated to at least 1400 degrees Celsius by one or more induction coil apparatus energized with one or more alternating current “AC” power waveforms during conversion of said feed into product syngas, wherein the gasification reactor comprises:
  • a refractory-lined vessel in operational communication with the gasification reactor for holding the melt; and
  • wherein the refractory-lined vessel is tilted at a determined tilt angle about a horizontal plane so as to allow a layer of molten slag formed during said conversion of the feed into product syngas to flow away from the refractory-lined vessel.
• 30. The gasification reactor of item 29 wherein the product syngas is directed to flow from the refractory-lined vessel to a powerplant for electric power generation, a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof.
• 31. The gasification reactor of item 29 or item 30, wherein the oxygen-carrying gas is selected from air, steam, oxygen, oxygen-enriched oxygen, carbon dioxide, or a combination thereof.
• 32. A method to perform gasification in a gasification reactor having a molten metal material disposed within the gasification reactor for converting a feed into product syngas by contacting feed into melt, wherein the melt is formed by inductive melting by one or more induction coil apparatus energized with one or more alternating current “AC” power waveform, the gasification reactor comprising a refractory-lined vessel in operational communication with the gasification reactor for holding melt, wherein the refractory-lined vessel is tilted and positioned at a pre-determined tilt angle about a horizontal plane to cause the refractory-lined vessel to be tilted at the pre-determined tilt angle with respect to the horizontal plane during conversion of feed into product syngas so as to direct molten slag material formed during conversion of feed into product syngas to flow away from the refractory-lined vessel at a pre-determined molten slag material flow rate.
• 33. The method of item 32, wherein the product syngas is directed to flow from refractory-lined vessel to a powerplant for electric power generation, a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof.
• 34. A method for conducting gasification of a feed into product syngas in a gasifier having a melt disposed within the gasifier, comprising injecting a feed into contact with the melt to dissolve at least a portion of feed into melt wherein melt is formed by inductive melting by one or more induction coil apparatus energized with one or more alternating current “AC” power waveforms, and directing the product syngas to flow through a steam generator device to transfer heat from said product syngas to steam generator device to cause generation of steam.
• 35. The method of item 34 comprising directing product syngas to flow through from steam generator device at a superficial gas velocity of at least 0.20 meters per second.
• 36. The method of item 34 wherein the melt disposed within gasifier is heated to a temperature of at least 1300 degrees C.
• 37. The method of item 34 wherein the feed is selected from coal, lignite, coal-liquid slurry, wood, biomass, municipal solid waste, sewage, crude oil, natural gas, petroleum residue, bituminous sand, seawater, shale oil material, peat, or a combination thereof.
• 38. The method of item 34 wherein product syngas is directed to flow from steam generator device to a powerplant for electric power generation, a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof.
• 39. The method of item 34 wherein a temperature of steam generated from the steam generator device is at least 400 degrees C.
• 40. The gasification reactor of item 24 wherein the pre-determined tilt angle is between 0 to 60 degrees.

Claims

1. A method to perform gasification in a gasification reactor having a molten metal material disposed within a refractory lined vessel of the gasification reactor for converting a feed into product syngas by contacting feed into melt, comprising

forming a melt by inductive melting by one or more induction coil apparatuses energized with one or more alternating current “AC” power waveforms;

injecting a feed into contact with the melt to dissolve at least a portion of the feed into the melt, wherein the feed is selected from coal, lignite, coal-liquid slurry, wood, biomass, municipal solid waste, sewage, crude oil, natural gas, petroleum residue, bituminous sand, seawater, shale oil material, peat, or a combination thereof;

tilting and positioning a refractory-lined vessel at a pre-determined tilt angle about a horizontal plane to cause the refractory-lined vessel to be tilted at said pre-determined tilt angle from said horizontal plane during a conversion of the feed into a product syngas;

directing molten slag material formed during conversion of the feed into product syngas to flow away from the refractory-lined vessel at a pre-determined molten slag material flow rate;

directing product syngas to flow from the refractory-lined vessel to a powerplant for electric power generation, a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof.

2. Method to perform gasification according to claim 1, wherein the pre-determined tilt angle is between 0 to 60 degrees.

3. Method to perform gasification according to claim 1, comprising directing product syngas to flow through a steam generator device to transfer heat from said product syngas to the steam generator device to cause generation of steam.

4. Method according to claim 1, wherein an oxygen-carrying gas is directed into the gasifier during gasification of the feed at a superficial gas velocity of at least about 10 meters per second.

5. Method according to claim 4, wherein the oxygen-carrying gas is selected from air, oxygen, carbon dioxide, or a combination thereof.

6. Gasification reactor for converting a feed into product syngas by contacting feed into a melt, the melt being disposed within the gasification reactor, the gasification reactor comprising

a refractory-lined vessel in operational communication with gasification reactor for holding the melt,

an induction coil apparatus for inductively heating the melt during a conversion of the feed into product syngas,

injection means for injecting a feed into contact with the melt to dissolve at least a portion of the feed into the melt,

tilting and positioning means for tilting and positioning the refractory-lined vessel at a pre-determined tilt angle about a horizontal plane to cause the refractory-lined vessel to be tilted at the pre-determined tilt angle with respect to the horizontal plane during a conversion of the feed into a product syngas;

a slag conduit for directing molten slag material formed during conversion of the feed into product syngas to flow away from the refractory-lined vessel at a pre-determined molten slag material flow rate;

a gas conduit for directing product syngas to flow from the refractory-lined vessel to a syngas processing apparatus.

7. The gasification reactor of claim 6, wherein the tilting and positioning means is configured such that the vessel can be tilted at a pre-determined tilt angle between 0 to 60 degrees.

8. The gasification reactor of claim 6, the gasification reactor comprising the sensor being configured to perform a multiplicity of measurements over a pre-determined time period to derive a plurality of data signals indicative of said multiplicity of measurements over the pre-determined time period; wherein the sensor further comprises a processor controller, the processor controller being configured to receive the derived plurality of data signals and to perform at least one algorithmic calculation to determine a proximate temperature of said flow-stream of the hot gasified product syngas within the pre-determined time period as sensed by the sensor; and the processor controller being configured to generate a control signal indicative of the proximate temperature addressed to a feedwater flow control valve pump so as to regulate and control the fluid flow of feedwater flowing in a steam generator device in fluid communication with said flow-stream of hot gasified product syngas.

a sensor configured within a designated interior wall surface of the said gasifier to receive a flow-stream of hot gasified product syngas evolving from the gasifier,

9. The gasification reactor of claim 8, wherein the processor controller is further configured to retrieve from electronic memory a default control signal indicative of a reference feedwater fluid flow rate, addressed to the feedwater flow control valve pump to regulate and control the fluid flow of feedwater flowing in the steam generator device according to said indicative reference feedwater fluid flow rate, in the event where processor controller is unable to generate determined proximate temperature from said received derived plurality of data signals.

10. The gasification reactor of claim 8, wherein the sensor is configured within the designated interior wall surface where the superficial gas velocity of said flow-stream of hot gasified product syngas evolving from the gasifier is at least about 2 meters per second.

11. The gasification reactor of claim 8 wherein the sensor is configured to be protruding a proximate distance of at least 1 inch from the surface of the designated wall surface.

12. The gasification reactor of claim 8, the sensor having an extendable member tubular body to travel on a perpendicular axis plane to the designated wall surface axis plane between a proximate distance of 1 inch to 8.5 inches.