Abstract: A method for reducing the rate of side wall corrosion in a coal-fired utility boiler. A plurality of side wall slots are provided in the side walls of the boiler so that a protective layer of air may be introduced through the slots and propelled upward by the updraft from the burners.

Abstract: Reduction of slagging is improved by targeting slag-reducing chemicals in a furnace with the aid of computational fluid dynamic modeling. Chemical utilization and boiler maintenance are improved.

Abstract: A method and apparatus for controlling NO.sub.x produced by a natural gas fired combustion source includes establishing a control curve for the combustion source for indicating NO.sub.x levels based on steam injection rates and fuel flow rates provided to the burners. The atomizing steam injection flow rate provided to the burner is measured as well as the fuel flow rate. A NO.sub.x level is determined for the combustion source based on the atomizing steam injection flow rate, the firing rate, and the fuel flow rate. NO.sub.x levels are lowered by adding atomized steam to the burners according to the pre-programmed control curve.

Abstract: A mechanical wiper mounted within an incinerator for waste gases, such as silane, and said wiper adapted to move adjacent selected internal surface areas to remove combustion products buildup on such selected areas.

Abstract: An improved process for reducing sulfur oxide emissions from the combustion of coal is disclosed wherein a fuel mixture comprising calcium-containing sorbent and coal is fed to the burners and sulfur oxides react with calcium from the sorbent in a high temperature sulfur capture region, followed by additional sulfur capture in a lower temperature, high humidity sulfur capture region prior to separation of particulates from the flue gas. Sulfur capture using calcium-containing sorbents can be combined with aggressive coal beneficiation techniques to further enhance reduction of sulfur oxide emissions. The process of the invention provides a process for reducing sulfur oxides that efficiently uses calcium-containing sorbents to enhance sulfur capture while reducing the need for expensive equipment or process modifications.

Abstract: A method and apparatus for deslagging a cyclone furnace in which a series of flexible hollow tubes are inserted into the combustion chamber and the explosive charges in each hollow tube are detonated sequentially. Each of the hollow tubes is biased outwardly against the accumulated slag and ash in the combustion chamber. The hollow tubes may be formed in arcs or rings in planes perpendicular to the longitudinal axis of the combustion chamber, and spacer rings may be positioned between each ring.

Abstract: SO.sub.x reduction treatments involving sorbent addition to coal-fired boilers is improved by retrofitting the boiler to burn fuel oil-in-water emulsions as a replacement for at least a portion of the coal. The ratio SO.sub.x removed to particulates produced can be significantly increased.

Abstract: A method and apparatus are employed to reduce the sulfur dioxide produced by the combustion of a sulfur-containing fule in a combustion chamber. Part of the combustion air is introduced into the combustion chamber with and closely adjacent the fuel. Another part of the combustion air is introduced into the combustion chamber above and downstream of the fuel and relatively remote therefrom under conditions which buffer the flame front and reduce peak flame temperatures therein. Finely divided limestone particles or the like are aspirated into the combustion chamber by the air introduced above the fuel and distributed thereby throughout the gases flowing downstream through the combustion chamber wherein the limestone particles are calcined to lime particles which react with the sulfur dioxide in the combustion reaction gases to produce calcium sulfate. There is no premixing of the particles and the aspirating air before they enter the combustion chamber.

Abstract: A method and apparatus are employed to reduce the sulfur dioxide produced by the combustion of a sulfur-containing fuel in a combustion chamber. Part of the combustion air is introduced into the combustion chamber with and closely adjacent the fuel. Another part of the combustion air is introduced into the combustion chamber above and downstream of the fuel and relatively remote therefrom under conditions when buffer the flame front and reduce peak flame temperatures therein. Finely divided limestone particles or the like are aspirated into the combustion chamber by the air introduced above the fuel and distributed thereby throughout the gases flowing downstream through the combustion chamber wherein the limestone particles are calcined to lime particles which react with the sulfur dioxide in the combustion reaction gases to produce calcium sulfate. There is no premixing of the particles and the aspirating air before they enter the combustion chamber.

Abstract: A burner assembly in which an inlet is located at one end of an annular passage for receiving fuel, and an outlet is located at the other end of the passage for discharging the fuel. A register assembly is provided which includes an enclosure for receiving air and a divider for directing the air from the enclosure towards the outlet in two parallel paths extending around the burner. Registers are disposed in each of the paths for regulating the quantity of air flowing through the paths and an injector is provided in the outer path for injecting sulfur adsorbent into the secondary air stream.

Abstract: A system for monitoring combustion of coal in a boiler detects coal composition and heating value using a bulk material analyzer and determines an air/fuel mixture so that when the coal is burned oxygen is available throughout the boiler and the wall temperature of the boiler is maintained below the metallurgical limit and the surface temperature below the ash fusion temperature of the coal where slagging is not desired. The temperature and pressure of steam in the boiler, fuel and air flow rates and temperature and oxygen content of the stack gases are supplied to a boiler model. The boiler model predicts how varying the air supply rate affects sensible heat loss. Periodic measurements of unburned carbon in the ash produced by combustion of the coal are correlated with the operation of the boiler at the time that the ash was produced to provide a basis for estimating unburned coal loss.

Abstract: A method of incinerating all kinds of wastes such as municipal waste, waste plastics, industrial waste, various kinds of waste slurries and waste liquid, etc. or fuels such as coal, oil cokes and bark, etc. using a fluidized bed type incinerator which employs a granular material as a fluidizing medium, said granular material comprising TiO.sub.2 or Al.sub.2 O.sub.3, particularly anatase-type TiO.sub.2 or .alpha.-Al.sub.2 O.sub.3, as the primary component thereof.

Abstract: A method is provided for reducing the sulfur content of exhaust gases from a combustion installation comprising the steps of calcining the dry sorbent particles in a controlled temperature environment outside of the combustion installation, forming an aqueous dispersion of the calcined sorbent and injecting the aqueous dispersion into the combustion installation.

Abstract: The invention is directed to the use of melting point enhancers to control slag build-up in garbage, medical waste and sludge incinerators. It is directed to a method of modifying the nature of low melting non-combustible components of garbage, medical waste and sludge by the addition of very high melting point metallic compounds so as to render the low melting point materials non adherent or less adherent and easier to remove from furnace surfaces.

Abstract: Corrosion and sulfuric acid formation in an integrated spray-drying and calcining operation is inhibited by operating the calciner at a temperature so that the exit gases from the calciner provides sufficient heat to the spray drier to keep the exit gases from the spray drier at a temperature above the dew point of the SO.sub.3 /H.sub.2 O vapors present in the spray drier exit gas.

Abstract: The generation of acid rain precursors, i.e., SO.sub.x and NO.sub.x, and slag during the combustion of a carbonaceous fuel, e.g., coal, is counteracted in a slagging combustor apparatus and process. The fuel is combusted in a primary combustor under substoichiometric combustion conditions and at a temperature greater than the fuel's ash fusion temperature. The substoichiometric combustion conditions suppress the formation of NO.sub.x. Most of the noncombustibles are separated from the gaseous products of combustion, in the form of liquid slag, to form treated gaseous combustion products having a noncombustible content that is substantially reduced with respect to the noncombustible content of the fuel. The temperature of the treated gaseous combustion as it leaves the primary combustion is above the ash fusion tmeprature of the fuel. A sorbent is introduced into the treated gaseous combustion products and calcined. The calcined sorbent removes SO.sub.x from the treated gaseous combustion products.

Abstract: A process for combusting a sulphur-bearing fuel is disclosed. A mixture of the fuel, a sulphur binding material and a sulphur retaining material is introduced into a first combustion zone. The mixture is combusted in the first zone under conditions of fuel-rich stoichiometry and temperature wherein substantially all of the sulphur is captured in a solid form by the sulphur binding material. The resulting captured sulphur compounds are then physically and/or chemically bound within or with the retaining material. Combustion products are thereby produced which include fuel-rich gases and solid flyash and slag containing mixtures of the captured sulphur and the binding and retaining materials. These combustion products are then further combusted in at least one additional fuel-rich combustion zone at temperatures above the fusion temperature of the solids, to melt the solids and to form complex, refractory mixtures and compounds containing the captured sulphur.

Abstract: In a coal fired boiler of the type having a combustion zone in which said coal is fired, a convection zone located downstream from said combustion zone and having a plurality of heater tubes disposed therein adapted to heat water or steam disposed therein, and in which convection zone combustion residues emanating from said coal have a tendency to stick to or agglomerate upon said tubes, a method of decreasing said tendency to stick or agglomerate, comprising burning said coal in the presence of an additive consisting essentially of super large magnesium oxide particles, a major mass fraction of which is about 150 microns in diameter or greater.

Abstract: The method of operation of a boiler system to which an additive is to be fed at a controlled rate and in which the optimal additive rate depends upon a plurality of changing parameters of the boiler system, in which the relationship between each of those parameters and the optimal additive feed rate is determined, the relevant parameters are sensed during the operation of the system, their effects on optimum additive feed are computed in accordance with said relationships and combined on a continuous basis to produce a control signal representative of the desired rate of additive feed, and controlling the additive feed in accordance therewith, all preferably continuously.

Abstract: Solid carbonaceous fuel, such as bituminous coal, is copulverized with a basic metal reactant to provide a microground prepared fuel predominantly in minus 325 mesh particles of high specific surface area. The prepared fuel is fed directly to a burner and effects ninety-five percent (95%) or better removal of the sulfur from the fuel prior to emission.

Abstract: A method of burning solid fuel having low melting point alkaline compositions, such as alkali metal salts, particularly lignite and salty brown coal. The fuel is introduced into the reaction chamber of a circulating fluidized bed reactor, and is mixed prior to introduction to the reaction chamber with a reactant material capable of reacting with the low melting point alkaline compositions of the fuel to produce high melting point alkali metal compounds during combustion. The temperature in the reaction chamber is kept below the melting point of the formed alkali metal compounds. The reactant material comprises silica oxide or a metal oxide, or hydroxide, of the group consisting of aluminum, calcium, magnesium, iron, titanium, and mixtures of two or more thereof. Kaolin is particularly effective, especially when the molar ratio of Al/(Na and K) is at least 1.0.

Abstract: A method of purging waste gases by adding to the gas, while it flows through an absorber, a neutralizing agent, such as lime, together with a liquid substance under such conditions that the liquid is evaporated and that a dry salt is left as reaction product. The absorption results in a reaction of the noxious compounds in the waste gases with the neutralizing agent, whereby dry salts are formed, which are removed from the absorber. The same neutralizing agent in the form of the aqueous solution or aqueous suspension may be used as the liquid substance. The liquid substance is supplied into the absorber downstream of the neutralized agent in the solid pulverized state.

Abstract: A coincineration process whereby sewage sludge or other toxic liquid chemical waste is incinerated with a supplemental fuel such as municipal refuse, coal, sawdust, tire chips and the like involves introducing the sewage sludge into the incineration zone by means of a pressure spray nozzle or a spinning cone or disc atomizer. In the form of ultrafine solids, liquid or gas, a supplemental fuel may be introduced with the sewage sludge. Supplemental fuel may also be introduced into the incinerator by conventional means. Addition of tire chips in the feed provides in a higher incineration zone temperature and significantly reduces dioxin compounds present in the incineration zone off gas. Also, to reduce the scaling and fouling of the boiler tubes and incinerator, to increase the density and pumpability of the sewage sludge, and to eliminate metal salt deposits from the incinerator, the boiler feedwater and the sewage sludge are each contacted with an electromagnetic field device prior to heating.

Abstract: The present invention improves flame combustion of liquid carbonaceous fuels by the preparation and use of a fuel additive comprising a finely-divided particulate hydrated compound in stable suspension in a liquid vehicle. The median major dimension of the primary particles of hydrated compound is preferably less than 10 microns. When employed at a level of from about 200 to about 5000 parts per million, the additive can improve the efficiency of combustion and reduce particulate emissions for flame combustion of liquid carbonaceous fuels, especially residual grades of fuel oil.

Abstract: Disclosed is a process for burning cattle dung at a temperature of from 500.degree. to 780.degree. C., preferably from 650.degree. to 780.degree. C., in the presence of one or more aluminum-containing substances selected from the class consisting of bauxite, kaolin and aluminum compound-containing ash from furnaces for firing solid fuels. A major part of the alkalies contained in the cattle dung and a substantial part of the chlorine are retained in combined form in the resulting furnace ash.

Abstract: The present invention contemplates a process for reducing the gaseous sulfur dioxide content of flue gases by either or both preheating coal prior to burning the preheated coal and controlling the combustion temperature level to control the amount of sulfur being converted to sulfates and remaining in the ash residue.

Abstract: A dry process for desulfurization of a power plant flue gas recovers, e.g. from an electrostatic precipitator, the solids which include unreacted absorbent, absorption reaction product and fly ash, and recycles at least part of this recovered solid product to contact with the flue gas for further absorption.

Abstract: In a solid fuel furnace, such as a boiler, having a combustion zone in which the fuel is fired, a convection zone located downstream from said combustion zone and having a plurality of heater tubes disposed therein adapted to heat water or steam disposed therein, and in which convection zone combustion resides emanating from said solid fuel have a tendency to stick to or agglomerate upon said tubes, a method of decreasing said tendency to stick or agglomerate, comprising burning said fuel in the presence of a chromium containing compound adapted to form a chromium oxide compound upon combustion thereof.

Abstract: A process for reducing the sulfur oxide content of flue gases produced by combustion of sulfur-containing coal containing cations of alkali metals, alkaline earth metals or both, in ion exchangeable form. Flue gases containing sulfur oxides are recycled to contact coal awaiting combustion. Sulfur oxides are absorbed on the coal during the contact step, which is conducted in the presence of water. Sulfur oxides react with alkali and alkaline earth metal cations, and are oxidized to form sulfate reaction products. When the treated coal is burned, these sulfate reaction products are retained in the coal ash.

Abstract: A process for reducing the formation of dioxins in the incineration of wastes that includes using sodium carbonate or sodium bicarbonate to react with chlorides formed in the incineration process. When sodium bicarbonate is used in the temperature range of 1561.degree. F. to 518.degree. F. a greater porosity is achieved that achieves a high degree of removal of the chlorides thereby preventing their reaction to produce dioxins.

Abstract: Flue gas resulting from combustion of sulfur-containing fuel is treated for reduction of its sulfur dioxide content by creating in it a suspension of finely divided sorbent such as lime, and then contacting it at elevated temperature in a vertical contacting zone with a descending shower of sulfur dioxide oxidation catalyst. The resulting sulfur trioxide is captured as a powdered sulfate.

Abstract: In a process for lowering the NO.sub.x content in combustion waste gases with the use of a reducing agent, the reducing agent has heretofore been added in all cases to the combustion gases downstream of the incineration. According to the invention, it is suggested in a fluidized-bed incineration to introduce the reducing agent into the fluidized bed. It is preferred, in this connection, to admix reducing agent to the utilized fuel and/or to the combustion air and/or to introduce the reducing agent directly into the incineration. Especially preferred reducing agents are NH.sub.3 or nitrogen-containing hydrocarbon compounds. Various additional versions of the feeding operation are possible.

Abstract: A method and annular burner for binding sulfur and other impurities during the combustion of fuels that contain such impurities. The fuel is burned in an annular burner flame that has an internal recirculation zone. An additive in the form of an aqueous suspension is sprayed into the combustion chamber via at least one two-component atomizing nozzle, and the additive is mixed with the gases of the flame under optimum reaction conditions. In order to enable a particularly favorable binding of noxious material, an atomizing nozzle for the additive is disposed in the central portion of the annular burner, and the additive is sprayed as an external mixture, via the atomizing nozzle, along the longitudinal axis of the burner flame, as a fine or narrow stream, through the internal recirculation zone and into the flame.

Abstract: A process for reducing the sulfur oxide content of flue gases produced by combustion of sulfur-containing coal containing cations of alkali metals, alkaline earth metals, or both, in ion exchangeable form. Flue gases containing sulfur oxides are recycled to contact coal awaiting combustion. Sulfur oxides are adsorbed on the coal during the contact step, react with alkali metal and alkaline earth metal cations, and are oxidized to form sulfate reaction products. When the treated coal is burned, these reaction products are retained in the coal ash.

Abstract: A method of binding sulfur compounds which are produced as reaction products during the combustion of sulfur-containing fuels in a charging bed or fluidized bed furnace at temperatures above 1000.degree. C. The method is effected by the addition of additives. The hot flue gases exiting directly from the charging bed or fluidized bed furnace pass through a cooling zone to lower the flue gas temperature to below 1000.degree. C. After this cooling zone, the additives are introduced into the cooled-off flue gas flow via a carrier medium. The charging bed or fluidized bed furnace for carrying out this method includes cooling surfaces for cooling the hot flue gases in the cooling zone. These cooling surfaces are disposed directly above the furnace surface and below the additive introduction surface. Cooling of the flue gases in the cooling zone can be effected by blowing in low-temperature flue gas between the upper edge of the furnace surface and the lower edge of the additive introduction surface.

Abstract: A process and devices with which the fused sulphur is removed from fossil fuels, preferably coke and petrocoke, ahead of the furnace or the like and is fused with an additive. In the combustion chamber, the additive with the fused sulphur is then sintered. The fuel is desulphurized at a temperature management controllable by an electronic process computer, at controllable residence times and pressure conditions in leading zones so that practically completely desulphurized fuel is burned in the combustion chamber. The sulphur components are removed with the additive via an ash removal plant. A combustion of the sulphur components of the fuel to SO.sub.2 within the combustion chamber does not occur.

Abstract: A process is disclosed for inhibiting corrosion of metal surfaces and deposition of particulates in an air preheater system. In the process, a composition (preferably aqueous) comprising a corrosion inhibiting amine and a surfactant having an HLB value of from about 8 to about 20, preferably from about 10 to about 14, is supplied to the combustion gas-in side and/or to the air-in side of the air preheater for protection of the metal surfaces and minimizing such deposits. In a preferred embodiment, the process of the invention can employ an amine salt of a C.sub.12 to C.sub.24 tertiary alkyl amine an amine oxide, or an amine oxide salt, either alone or with a surfactant.

Abstract: A liquid borate is added to sulfur trioxide-containing combustion gases at a temperature of from about 250.degree. to about 1000.degree. F. in a boiler or other furnace system. The borate neutralizes sulfuric acid in the gases and inhibits sulfuric acid corrosion and deposition on metal surfaces of the system that contact the gases. An organic deposit modifying agent such as sorbitol and an additional acid neutralizing agent such as an alkali metal hydroxide, aluminate, or silicate may also be added to the combustion gases.

Abstract: A process for eliminating, reducing or modifying slagging, convective tube fouling, corrosion, sulfur trioxide formation, acid smut and plume visibility by intermittently injecting pressure-hydrated dolomitic lime consisting of porous, particles having a high specific surface and a low settling rate in water into the interior of a combustion system.

Abstract: A method of binding vanadium compounds which are formed as reaction products during the combustion of solid or fluid petroleum residues in vapor generators. The binding of the vanadium compounds is effected within the framework of a combustion with alkali earth containing coals which are preferably high-ash coals. With solid petroleum residues, the coal is mixed with the residue prior to entry into the combustion zone. With fluid petroleum residues, the coal is introduced into the combustion zone via a burner along with, yet separate from, the residues.

Abstract: Flue gas is desulfurized by mixing into the combustion zone a finely divided sorbent such as calcium carbonate and, downstream of the mixing point, reactivating the sorbent by spraying the gaseous suspension with an aqueous solution of solubilizing agent such as a deliquescent compound or a strongly ionizing inorganic salt.

Abstract: Flue gases from two or more boilers are treated for reduction of their sulfur dioxide content by injecting as sorbent fine limestone or dolomite into one of the boilers, recovering a mixture of spent and calcined sorbent from the resulting flue gas, hydrating the resulting mixture to provide a dry slaked sorbent, and adding the dry slaked sorbent to sulfur-containing flue gas from a second boiler at a temperature of about 120.degree. to 230.degree. C.

Abstract: A method for desulfurizing exhaust gases such as flue gases from steam generators that have been charged with brown coal, in which powdered lime is charged into the furnace and then removed or precipitated from the flowing exhaust gases after a certain reaction time. The dust or particulate matter which has been removed from the flowing exhaust gas stream, and which is at least partially charged with noxious substances along the surfaces thereof, is pulverized and then subjected to dry stream hydration, followed by recycling into the flue gas stream which has been cooled to a lower temperature. During the dry steam treatment, the points of fracture or exposure of the pulverized particulate additive are activated so that Ca(OH).sub.2 formation takes place, which has a high affinity for sulfur dioxide at low temperature. An apparatus for pulverizing and hydrating the particulate matter is also provided.

Abstract: A method of binding sulfur compounds, which result as react products during the combustion of sulfur-containing fuels in firing equipment, by the addition of additives. A mixture of alkali carbonate and an alkaline earth oxide, for example a mixture of sodium carbonate and magnesium oxide, are used as the additive. Such a mixture may include approximately one part by weight sodium carbonate and approximately two parts by weight magnesium oxide.

Abstract: A combustion process is disclosed for burning a fuel containing sulfur characterized by low sulfur and particulate emission and formation of solid, non-toxic sulfur compounds. The process comprises mixing the sulfur containing fuel with an additive capable of reacting with sulfur; burning the mixture in a first combustion stage with less than 75% theoretical air and at a temperature below the melting point of the ash, but sufficiently high to cause reaction between the additive and any sulfur in the fuel to facilitate removal of the sulfur compounds formed; passing combustible fuel gases and particulates from the first stage to one or more further stages to complete the combustion of the fuel; and oxidizing, in a separate zone, sulfur compounds formed in the first reaction zone by reaction between the additive and the sulfur in the fuel to form non-toxic sulfates.

Abstract: In a coal fired boiler of the type having a combustion zone in which said coal is fired, a convection zone located downstream from said combustion zone and having a plurality of heater tubes disposed therein adapted to heat water or steam disposed therein, and in which convection zone combustion residues emanating from said coal have a tendency to stick to or agglomerate upon said tubes, a method of decreasing said tendency to stick or agglomerate, comprising burning said coal in the presence of an additive consisting essentially of amorphous silica particles, substantially all of said particles being greater than about 30 microns in diameter.

Abstract: The concentration of nitrogen oxides contained in exhaust combustion gases is decreased by feeding into the combustion system within a heating furnace the combination of an ammonium compound and a phenol compound, the combination of Fluid Catalytic Cracking gasoline tank bottom water or water obtained after washing Fluid Catalytic Cracking gasoline and an ammonium compound, or FCC overhead condensate.

Abstract: There is described a method of removing oxides of sulfur from the emissions of fossil fuel combustion by injecting portland cement into the boiler with the fuel, the combustion air, or downstream with the combustion gases. There is also described the cement products that result from this method.

Abstract: A process and apparatus for removing sulfur oxide from combustion gas to form Na.sub.2 SO.sub.4 and for reducing the harmful effects of Na.sub.2 SO.sub.4 on auxiliary heat exchangers in which a sodium compound is injected into the hot combustion gas forming liquid Na.sub.2 SO.sub.4 in a gas-gas reaction and the resultant gas containing Na.sub.2 SO.sub.4 is cooled to below about 1150.degree. K. to form particles of Na.sub.2 SO.sub.4 prior to contact with at least one heat exchanger with the cooling being provided by the recycling of combustion gas from a cooled zone downstream from the introduction of the cooling gas.

Abstract: A three-stage combustion process is disclosed for burning a fuel containing sulfur characterized by low sulfur emission and good ash removal. The process comprises mixing the sulfur containing fuel with an additive capable of reacting with sulfur; burning the mixture in a first combustion stage with less than 75% theoretical air and at a temperature below the melting point of the ash but sufficiently high to cause reaction between the additive and any sulfur in the fuel to facilitate removal of the sulfur compounds formed; removing at least a portion of the sulfur compounds formed in the first stage; passing combustible gases from the first stage to a second stage; burning the gases in the second stage with less than 100% theoretical air at a temperature above the melting point of the ash to form a liquid slag which is removable from the second stage; and burning combustible gases from the second stage in a third stage with an excess of air to ensure complete combustion of the fuel.