Abstract: Coke deposits are removed from particulates by combustion in a regenerator by a process in which air is initially used as the oxidant. The combustion gas is subjected to a separation process to remove nitrogen therefrom, and the remaining carbon dioxide-enriched gas stream is recycled to the regenerator together while substantially pure oxygen is introduced into the regenerator. As the level of carbon dioxide in the system increases, the amount of air being introduced into the regenerator is gradually reduced and, in compensation, the amount of oxygen flowing to the regenerator is gradually increased. Eventually, part or all of the air is replaced by oxygen and carbon dioxide recycle gas, and the level of oxygen and carbon dioxide are regulated to maintain the desired temperature in the regenerator.

Abstract: A process and low-shaft furnace for disposing of filter material. The material to be disposed of is charged via a charging device onto and/or into a slag bath in the furnace. Simultaneously, additives comprising fluxing agents, slag-making constituents and reducing agents are introduced into the slag via a separate immersion lance. Finally, during the introduction of the additives the variables forming the electrical resistance, essentially the electrodiameter, center distance between the electrodes, level of the slag bath, and the immersion depth of the electrodes in the bath are adjusted so that 70% of the electrical energy is introduced between the electrodes and 30% of the electrical energy is introduced between the electrodes and the metal bath on the hearth bottom.

Abstract: A furnace comprises an enclosure, a hearth plate within the enclosure for supporting combustible material, a first heater element adjacent the hearth plate for initial combustion of the combustible material, a filter disposed above the hearth plate for filtering uncombusted products of combustion of the combustible material, and a second heater element adjacent the filter for final combustion of the uncombusted products of combustion filtered by the filter. A controller controls the first and second heater elements independently.

Abstract: In order to maintain the flue gas temperature from a steam generator up to the temperature required for a NO.sub.x catalytic reactor during low load operations, the flow of feedwater through the steam generator economizer is controlled to control the degree to which the flue gas is cooled as it passes over the economizer heat exchange surface. More specifically, an economizer bypass line is provided and the flow of feedwater during low load operations through the bypass line and the economizer is regulated to maintain a desired flue gas temperature to the catalytic reactor. As the flue gas temperature changes with load, the flow through the economizer and bypass line is modulated to maintain a proper temperature. At full or near full load, the bypass line is fully closed.

Abstract: A process for incinerating solids, especially for burning rubbish in a combustion vessel comprising at least one combustion chamber and an after-burner chamber. Here, instead of secondary or tertiary air, water vapor under increased pressure is sprayed into the combustion vessel after the combustion gases have left the combustion chamber. Only primary air is supplied as the combustion air. In this manner and with the use of minimum quantities of combustion air, it is possible to increase the effectiveness of the overall process while at the same time reducing the emission of pollutants. It is also possible to feed back flue gas together with the water vapor, so that, for example, the maximum temperatures, the temperature reduction and the dwell times in the 1st and 2nd flue of the vessel can be easily set to the optima.

Abstract: A system and method are disclosed for lowering NO.sub.x levels in flue gases of a fluidized bed reactor using selective non-catalytic reduction. A reactor is connected to a separator by a duct, and a reactant is introduced into the duct for decreasing NO.sub.x levels in the flue gases passing from the reactor, through the duct, and into the separator. The reactant, such as ammonia or urea, is selectively injected into a gaseous-rich region of the duct, near an upper, inner portion of the duct, so that a high degree of mixing of the reactant with flue gases is achieved while maintaining a low degree of mixing of the reactant with the particulate materials. The point of injection of the reactant into the duct is also at a location nearer to the reactor than to the separator to provide for increased residence time. In this manner, the reactant is used efficiently while obtaining the desired lowering of NO.sub.x levels in the flue gases.

Abstract: A disposal of waste material including water, volatile components and vitrifiable components, the waste material is heated in a dehydrator to remove the water, heated in a high-temperature dryer to vaporize hydrocarbon liquids, and then fed to the focus point of a primary plasma reactor where plasma arc jets are focused on the surface of a pool of the vitrifiable components. At the focus point the vitrifiable components are melted, and the volatile components are volatized. The melted vitrifiable components are received in a quench chamber where they solidify on a quench roller and are broken into chips and delivered to a receiving area. Heat from the quench chamber is transferred to the dehydrator and high-temperature dryer. The hydrocarbon liquids and volatized components are fed to a secondary plasma reactor where they are disassociated into their elemental components.

Abstract: A method for the selective control of the sulfur trioxide concentration in flue gases, to enhance the ash removal efficiency of electrostatic precipitators, which includes: catalytically converting a portion of the sulfur dioxide contained within the flue gas to sulfur trioxide, by passing a portion of such flue gas through at least one catalyst containing converter module which is positioned within such a flue gas stream; and selectively varying the quantity of flue gas passing through such module by providing an aspirating force to cause flue gas to be drawn through such a converter module.

Abstract: An apparatus for the selective control of the sulfur trioxide concentration in flue gases, to enhance the ash removal efficiency of electrostatic precipitators, which includes: catalytically converting a portion of the sulfur dioxide contained within the flue gas to sulfur trioxide, by passing a portion of such flue gas through at least one catalyst containing converter module which is positioned within such a flue gas stream; and selectively varying the quantity of flue gas passing through such module by providing an aspirating force to cause flue gas to be drawn through such a converter module.

Abstract: A method for controlling gas flow direction through a regenerative incinerator system coupled to a flow reversing valve, and for reversing the flow direction of the gas stream through the regenerative incinerator system. The regenerative incinerator system having a combustion zone and one or more heat accumulating and heat exchanging zones. The method establishes a combustion zone base temperature set-point, or T.sub.CB for referencing combustion zone temperatures, or T.sub.C 's, and an outlet base temperature set-point, or T.sub.OB, for referencing outlet temperatures, or T.sub.O 's, from the regenerative incinerator system. A switching temperature, or T.sub.S, is also established as a function of T.sub.C, T.sub.CB and T.sub.OB such that the slope of said function, i.e. dT.sub.S /dT.sub.C, is never negative over a predetermined range of combustion zone temperatures, or T.sub.C 's. The switching temperature being equal to T.sub.OB when the combustion zone temperature is equal to T.sub.CB.

Abstract: Repowering industrial and utility boilers with a circulating fluidized bed combustor to reduce SOx and NOx emissions emanating from the boilers by the following steps.First combusting high sulfur-containing carbonaceous solid fuel in a circulating fluidized bed combustor in admixture with limestone and air.Secondly combusting a carbonaceous fuel in an industrial or utility boiler.Thirdly mixing the flue gases generated in the circulating fluidized bed combustor with the exhaust gases produced in the industrial or utility boiler.Finally controlling the total heat generation by maintaining the circulating fluidized bed heat input to the boiler furnace from about 70 to 90% and the heat input of the boiler furnace from about 30 to 10%.

Abstract: Smeltable dust and pieces of grate slag in the proportions in which they are produced by a garbage incinerator can be disposed of by simultaneously melting them in a low-shaft electric furnace having at least one electrode extending into a molten slag bath which is maintained in the furnace covered by a layer of coke. The dust is introduced below the coke layer by a lance or tubular electrode while the pieces of grate slag are introduced above the molten slag both. The proportions of the two are maintained so that the leachate from the solidified slag when deposited in a landfill, conforms to the statutory requirements of clean drinking water laws.

Abstract: In the filtering of high temperature (e.g. greater than 400.degree. C.) and high pressure (e.g. greater than 5 bar) gas--such as produced by pressurized fluidized bed combustion or gasification of coal--there is often a buildup of particles on the supporting elements for the filters, and on surrounding structures. This buildup of particles can damage the filter elements, or greatly reduce their effectiveness. This problem is avoided by periodically automatically cleaning the supporting and/or surrounding surfaces of the filters, as by directing high pressure gas streams at the supporting and/or surrounding surfaces. The filters may also be backflushed with compressed gas, as is conventional, at the same time as, or at different times than, when the supporting and/or surrounding structures are cleaned. Conduits with nozzles may be mounted directly on the supporting and/or surrounding surfaces and connected by a pipe with an automatically controlled valve to a source of high pressure fluid.

Abstract: Destruction of noxious materials. The noxious material is fed batchwise into a combustion furnace holding a burning coal bed which induces combustion or detonation and also serves as damper for explosion fragments. Burning combustion gases are withdrawn from the upper part of the furnace and conducted while burning to a gas/solid separator. Optionally the burnt out combustion gases are bubbled through water or aqueous solution for the absorption of poisonous gas components and an essentially clean carbon dioxide/air mixture is discharged to the atmosphere.

Abstract: A method and apparatus for the selective control of the sulfur trioxide concentration in flue gases, to enhance the ash removal efficiency of electrostatic precipitators, which includes supporting a catalyst in the path of the flue gas, catalytically converting a portion of the sulfur dioxide contained within such flue gas to sulfur trioxide, by passing at portion of such flue gases over a catalyst which is positioned within the path; selectively varying the amount of sulfur trioxide produced by the catalytically converting, by selectively changing the quantity of flue gas flowing through such catalyst; and simultaneously maintaining the ratio of the pressure loss coefficient of the flue gas flowing through the other portion of such duct, in the vicinity of such catalyst, within a predetermined range.

Abstract: A flue gas emission control system for coal fired boilers use individual units for NO.sub.x, SO.sub.x and particulate removal and provides ammonia injection to all three units from a single source.

Abstract: An intelligent oxygen injection control system for afterburners which minimizes transient incinerator pollutant emissions while simultaneously minimizing oxygen consumption. A fuzzy logic-based controller utilizes inputs from sensors that measure gas phase pollutant species such as hydrocarbons and carbon monoxide to control oxygen injection and thus minimize pollutant emissions while minimizing oxygen consumption.

Abstract: A method for operating a coal-fired power plant with a dry-firing furnace includes the steps of supplying coal as a fuel and adding a Ca-containing substance to the coal. The amount of Ca-containing substance is adjusted such that such that after addition of a CaO contents of at least 0.3% is obtained. The coal with the added Ca-containing substance is burned in the dry-firing furnace whereby a flue gas is produced. The flue gas is guided through a NO.sub.x removal device, an air preheater, a particle separator, and a desulfurization device.

Abstract: A process for burning fuel includes the following steps: burning a fuel; putting an inner shell formed in a course of soot formation into contact with other components in a combustion gas to promote a chemical reaction of the other components in the combustion gas prior to the formation of an outer shell; and at the same time, inhibiting the formation of the outer shell around the inner shell. By this process, the discharged NO.sub.x gas is reduced and the amount of discharged soot is decreased.

Abstract: A process for the in-situ production of an effluent sorbent-oxide aerosol during the combustion of a hydrocarbon containing fuel whereby the effluents are removed from the resultant gaseous hydrocarbon stream comprises admixing an aqueous solution of the sorbent with the fuel, atomizing and combusting the mixture under controlled conditions so as to generate the effluent sorbent-oxide aerosol.

Abstract: Methods and apparatus are provided for combustion systems wherein fuel may be burned completely with use of air as the oxidant, without the necessity for completely mixing the fuel with the air before, during, or after the combustion process. A bed of readily reducible metal oxide, the reduced form of this metal oxide being readily oxidized, is placed within a combustion system. The air and fuel are contacted with the bed at an elevated temperature, with the metal oxide oxidizing the fuel and being regenerated by the air. In one embodiment, complete combustion of fuel occurs without complete mixing of fuel and air. In other embodiments fuel can be burned with little or no mixing with a the combustion process, or fuel can be burned with little or no mixing with air, before, during, or after the combustion process, thereby avoiding a number of disadvantages of such mixing.

Abstract: A system for protecting the material of a gas-gas heater which receives a raw flue gas for being provided to a desulfurization plant for cleaning of the flue gas comprises a path of raw flue gas having a gas temperature which is provided to the heater. A quench device communicates with the raw flue gas flow for providing a rapid cooling of the raw flue gas. A controller communicates with the flow of raw flue gas and the quench device. The controller has a variable, pre-set temperature value which is the temperature at which the material of the heater can be damaged. The controller monitors the temperature of the raw flue gas for detecting when the temperature of the raw flue gas is greater than the pre-set temperature value for activating the quench device in order to provide a rapid cooling of the raw flue gas until the gas temperature is less than the pre-set temperature value.

Abstract: An arrangement for hot killing the acid contents of flue and process gases comprising a burner for discharging fuel and combustion supporter, preferably Diesel oil, fuel oil and air, to a combustion chamber, to produce a flame and gas burnt, and means of injecting/blowing a basic substance in either powder or solution form into a hot region of the flame, the gas burnt thus enriched with basic substance being mixed with the flue gas and hot killing its acid contents.

Abstract: A process for treating an exhaust stream which includes high levels of noxious compounds containing chemically bound nitrogen, to produce an effluent stream that is extremely low in oxides of nitrogen and environmentally safe for discharge into the atmosphere. A source of oxygen and fuel is added to the exhaust stream to create a fuel-rich mixture, the quantity of fuel being sufficient to react with the available oxygen. The fuel-enriched stream is provided to a thermal reactor and reacted to provide a heated oxygen-depleted stream which includes quantities of by-product NO.sub.x, which stream is then cooled to 800.degree. to 1000.degree. F. Conversion oxygen is added to the cooled stream which is then passed over a first catalyst bed under overall reducing conditions, the quantity of conversion oxygen added being in stoichiometric excess of the amount of NO.sub.x in the stream, but less than the amount of combustibles, whereby the NO.sub.x is first oxidized to NO.sub.2, and then the NO.sub.

Abstract: A process for the in-situ production of an effluent sorbent-oxide aerosol with promoter during the combustion of a hydrocarbon containing fuel whereby the effluents are removed from the resultant gaseous hydrocarbon stream comprises admixing an aqueous solution of the sorbent and promoter with the fuel, atomizing and combusting the mixture under controlled conditions so as to generate the effluent sorbent-oxide aerosol.

Abstract: Process and system for the operation of a fireplace or the like in which combustion products including pollutant gases and entrained particulate materials are treated to substantially reduce pollutant levels. The combustion products are passed through a confined flue passageway, such as found in a chimney stack, which extends upwardly to the exterior of the dwelling house or other structure. The flow of combustion products is interrupted in a manner to cause the products to follow a tortuous path in which entrained particulates in the combustion products are separated so that they collect in a suitable disposal zone. The combustion products then pass into an afterburner section comprising a plurality of heating elements. The temperature of the combustion products is sensed below the afterburner section and above bank of heating elements.

Abstract: A low-temperature carbonization/combustion process is carried out in a low-temperature carbonization/combustion plant with pressure control that includes a pyrolysis drum to which waste is delivered. Low-temperature carbonization gas generated there is passed to a combustion chamber. Flue gas produced there is fed through a cooling device and a gas compressor to a stack. With the aid of a control device, the speed of rotation of the gas compressor is controlled in relation to the pressure in the gas path between the pyrolysis drum and the gas compressor in such a way that when the pressure decreases, the speed of rotation is decreased. Preferably, an additional gas compressor is connected in series with the gas compressor and the speed of rotation of the additional gas compressor is appropriately controlled. An additional pyrolysis drum can also be provided.

Abstract: In order to work up pyrotechnical material, I. the pyrotechnical material is burned in a controlled manner, the slag is optionally allowed to continue reacting and the crude gas formed is passed through a high-temperature region in which the gas is exposed to a temperature of at least 1200.degree. C. over a predetermined period in order to decompose organic substances still present; II. the crude gas formed during the combustion is cooled to a temperature below 400.degree. C.; III. the crude gas is purified under dry conditions by first feeding it into a preliminary separator, coarse particles being separated off, and then feeding the crude gas via fine dust filters in order to separate off finely divided solids and/or IV. the crude gas is optionally purified under wet conditions by first passing it through a rotary scrubber and then passing it via one or more absorption units and V. the purified gas is released as waste air.

Abstract: A method of operating an industrial furnace comprising the steps of; drawing a first gas flow of ambient air into the furnace; removing constituents of the first gas flow to increase the relative oxygen content of the remaining first gas flow, the removed constituents of the first gas flow comprising a second gas flow; firing the furnace using at least part of the remaining first gas flow as an oxidising medium; drawing waste gases from the furnace in a third gas flow; combining the second gas flow and the third gas flow; and releasing the combined second and third gas flows from the furnace.

Abstract: A pulverized coal steam generator employing tangential, concentric firing with oxidizing conditions adjacent the furnace walls and using overfire air and low NO.sub.x firing methods is operated at very low excess air levels. This is possible because the unburned carbon in the flyash is measured and the pulverizers are adjusted to control the particles size of the pulverized coal and maintain a desired carbon level. The slagging and corrosion associated with deep staging is overcome by the concentric firing. Overall plant efficiency is obtained while still meeting performance objectives and emissions controls.

Abstract: The invention relates to a method of destroying explosive substances in which the explosive substances are converted to a pumpable liquid or suspension which is not detonatable but combustible and which can be burned in conventional boilers intended for energy production. The explosive substance is dissolved or suspended in a combustible liquid which contains no available oxygen or only a small amount of available oxygen, preferably fuel oil, wherein the amount of liquid present is so large as to reduce the energy content of the mixture to 1 MJ/kg or less in the absence of available atmospheric oxygen. The mixture is burned in a combustion apparatus, by delivering the mixture to the combustion apparatus via a liquid fuel burner or a burner for solid fuel/liquid fuel suspensions. The grain size of the explosive substance in suspension is selected so that each grain will be incinerated during its residence time in the flame of the burner concerned.

Abstract: A method for the destruction of contaminated waste material comprising the steps of sufficiently heating the waste material in an oxygen deficient atmosphere to pyrolyze the material thereby producing a volatile fuel gas stream and a decontaminated solid residue, separately removing the fuel gas stream and the decontaminated solid residue, adjusting the stoichiometric ratio of the fuel gas stream reactant components for combustion downstream, oxidatively combusting the adjusted fuel gas stream to produce a low velocity, low oxygen gas stream, and a high velocity, low oxygen carrier gas stream, recycling at least a portion of the high velocity, low oxygen carrier gas stream for direct contact with the waste material to provide heat for pyrolysis of the same, contacting at least a portion of the low velocity, low oxygen carrier gas stream with water to produce an oxygen rich, substantially inert, heat exchange gas stream and indirectly heating the contaminated material with the heat exchange gas stream to provi

Abstract: Method and apparatus for reducing the NOX levels in stack emissions of compact boilers and fluid heaters through selective injection of exhaust flue gases into the combustion process. Flue gas injection into the primary and secondary air of the burner along with flue gas injection directly into the combustion process is utilized. Injection of generated steam from a compact boiler, selectively injected into the combustion process is also provided.

Abstract: A method for removing gaseous pollutants from a polluted flue gas stream of an oil or coal-fired combustion furnace. A source of liquified combustible gas and a combustible gas-fired furnace are provided. The polluted flue gas stream is passed through a dust removal apparatus and removes flue dust from the flue gas stream so as to provide a de-dusted flue gas stream. Heat is recovered from the flue gas to generate power therefrom. The de-dusted flue gas is compressed to a pressure of at least 10 psi gauge using the generated power to at least in part compress the de-dusted flue gas. The compressed flue gas and the combustible gas are passed through at least one multi-sided heat exchanger, where the compressed flue gas is first passed through one side thereof and the liquified combustible gas in an at least partially vaporized state is passed through another side thereof. The compressed flue gas is cooled sufficiently by the combustible gas that water and at least one gaseous pollutant of NO.sub.2, SO.sub.

Abstract: A method of reducing the nitrogen oxide level in the flue gases issuing from combustion units by introduction of reducing agents into contact with gases containing nitrogen oxides in first and second reducing stages, is provided. The first reducing stage is a non-catalytic stage (e.g. at temperatures over 800.degree. C.), while the second stage is a catalytic stage (e.g. at temperatures of about 300.degree.-400.degree. C.). A steam generation boiler with improved nitrogen reduction facilities is also provided. The amount of nitrogen oxides in the hot gases is reduced in the combination of the first and second reducing stages while producing steam in a steam generation boiler system, thus resulting in gases essentially free from nitrogen oxides while eliminating the possibility of NH.sub.3 (or other reducing agent) slip in the exhausted flue gases. Heat transfers in a convection section as used to establish stabilized temperature conditions for catalytic reduction.

Abstract: A system and process for treating solid and liquid wastes, where the solid waste is separated from the liquid waste in a chamber, the liquid waste is passed out of the chamber, the solid waste is converted to ash, a fluid such as liquid waste is introduced into the chamber and combined with the ash, and the ash and fluid are exhausted out of the chamber together. Preferably, the system includes the use of hot air to agitate the solids during their conversion to ash. Desirably, the system also includes a filter and means to swirl the liquid waste as it exits the chamber, so that the liquid waste evenly distributes the solid waste within the filter as the liquid waste is exhausted.

Abstract: A small energy efficient afterburner for oxidizing the byproducts of incomplete combustion is disclosed. Gases are forced into a firebox, where a heating element maintains a temperature above the flash point for the more common and undesirable pollutants. Typical temperatures are 500.degree. C. to 800.degree. C. for burning hydrocarbons coming from internal combustion engines or wood stoves. After gases pass through the firebox, they are forced into a chamber adjacent to the firebox intake, so that heat energy may be transferred to the incoming gases, thereby greatly increasing the thermal efficiency of the device. Greater efficiencies are achieved by putting a catalytic surface in the firebox, and by insulating the afterburner exterior.

Abstract: The invention relates to a method of firing black liquor in recovery boilers where the intention is to obtain fumes having a low content of nitrogen oxides (NO.sub.x). A part of the combustion air is added as a last portion at a very high level so that a reducing atmosphere will exist in a very great part of the boiler for a long time period, e.g. at least 3-5 seconds.

Abstract: A flue gas conditioning system uses the waste heat of the flue gas to heat a sulfuric acid solution to add sufficient heat energy to the solution to vaporize the solution before being injected into the flue gas to condition the flue gas so that particulate removal by a precipitator is enhanced.

Abstract: A method and an incinerator in which halogenated organic compounds are burned in the presence of oxygen or oxygen enriched air to produce combustion products. The combustion products potentially include unreacted oxygen and halogenated organic compounds which can react with oxygen to produce halogenated furans and dioxins. The formation of the halogenated furans and dioxins is minimized by firing a burner, burning a hydrogen containing fuel at a fuel-rich stoichiometry, into the combustion products so that the fuel will react with the unreacted oxygen. This will reduce formation of the halogenated furans and dioxins. Any of the halogenated furans and dioxins that are formed are substantially eliminated by the reaction of hydrogen supplied by the fuel with the halogenated furans and dioxins.

Abstract: The amount of N.sub.2 O emission from a fluidized bed reactor is reduced by adding a hydrogen radical providing additive (e.g. a hydrogen containing fuel such as natural gas or alcohol) to the flue gases discharged from the fluidized bed. Sufficient oxygen is present in the flue gases--either by addition with the additive, or by addition of an excess to the combustion chamber--so that the additive reacts with the oxygen, typically raising the temperature of the flue gases (e.g. from about 700.degree.-900.degree. C. to about 950.degree.-1100.degree. C.) that is from about 1292.degree.-1652.degree. F. to about 1742.degree.-2012.degree. F. so that N.sub.2 O production is reduced about 10-90%. The additive may be injected in or just prior to a cyclone for separating particles from the flue gases, in a gas discharge immediately after the cyclone (e.g.

Abstract: A method and apparatus for low NOX combustion of natural gas in a compact steam boiler having output steam delivery controlled by predetermined outlet steam pressure. The compact boiler employs a small high heat release combustor discharging into a forced draft convective heat exchange section. In operation, the compact boiler is completely and automatically self-operating, employing flue gas recirculation (FGR) wherein the FGR is admitted into the burner combustion air through a valve controlled by boiler flue gas NOX content. A novel bell mouthed flue gas scoop is utilized in the boiler stack upstream of the NOX sensor. In an alternate combustion chamber design, a cylindrical water wall coil surrounds the combustion process, increasing boiler efficiency through the inherent large temperature difference between the coil and the combustion in process, along with reducing the combustion temperature and further reducing the NOX content of combustion products.

Abstract: A regenerative bed incinerator 10 is provided with a gas recirculation duct 80 through which a controlled amount of gaseous fuel is injected in the contaminated process exhaust gases 3 prior to admission to the regenerative bed incinerator 10 to increase the heating value of the process exhaust gases 3 so as to improve overall contaminated destruction efficiency for process exhaust gases which have a low level of combustible contaminants therein.

Abstract: An incineration process which can utilize any type of incineration means for disposing of hazardous, as well as non-hazardous, burnable waste. Such waste include toxic combustible liquids, oil slurries, soils contaminated with dioxin, PCBs, creosote, or any other potentially toxic combustible material. In particular, the present invention relates to an incineration process which has no continuous stack discharge of polutants. In this process, the flue gas stream from the incineration stages is enriched with oxygen and fed to a downstream combustion zone. A portion of the flue gas stream from the downstream combustion zone is enriched with oxygen and recycled to the incineration means. The remaining portion of the flue gas stream from the downstream combustion zone is scrubbed to remove acid gases and passed through a purification zone wherein any remaining contaminates are removed.

Abstract: Dust like substances which are recovered from a garbage or refuse incinerator are destroyed, eliminated or disposed of by smelting in a low shaft electric furnace having at least one electrode heating a slag melt therein. The dust is introduced into the melt by a lance opening beneath the melting surface and gas produced by the smelting process is subjected to cleaning. The slag may be continuously or discontinuously withdrawn and slag formers may be compensatorily added. A metal bath consisting predominantly of iron may be provided below the slag melt to protect metallic components of the dust upon the smelting thereof.

Abstract: A method for combusting a fossil material so as to produce an exhaust stream having a low level of pollutants. The fossil material is introduced into a fluidized bed combustor which is operated at a temperature of at least approximately 1775.degree. F. to produce a partially cleansed exhaust stream having a low level of N.sub.2 O. SO.sub.2 is removed from the partially cleansed exhaust stream outside of the fluidized bed combustor to produce a cleansed exhaust stream having a low level of SO.sub.2. An apparatus is provided for performing the method of the invention.

Abstract: A regenerative thermal oxidizer for oxidizing a contaminant in an air or other gas stream includes a heat transfer material which heats the incoming air and collects heat from the exiting air. The direction of flow of the air through the oxidizer is periodically reverse for the regenerative heat exchange. When flow is reversed, a quantity of untreated air in the oxidizer which would otherwise be discharged to the atmosphere is collected in a purge chamber which surrounds the lower portion of the discharge stack. The untreated air enters the bottom of the chamber and the air already in the chamber is forced out from vent holes in the top of the chamber into the stack. The untreated air in the chamber is fed back to the oxidizer through the inlet of the blower feeding the oxidizer while clean air is drawn into the chamber from the stack through the vent holes.

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 treating the exhaust gases of a combustion process, the exhaust gases comprising in part condensable or solidifiable particulate matter and residual hazardous organic compounds and emanating from the combustion process at a first temperature, by heating a portion of the exhaust gases using a heating means within a bypass means to a second temperature higher than the first temperature, maintaining the heated exhaust gases within the bypass means at the second temperature for a time sufficient to render the desired poriton of the residual hazardous organic compounds harmless, and then cooling the heated exhaust gases using a quench means within the bypass means to a third temperature lower than the first temperature in a period of time short enough to prevent the condensable or solidifiable particulate matter from condensing or solidifying on and adhering to the bypass means.

Abstract: A method of purifying combustion gases by removing acid gases therefrom, wherein a stream of combustion gases is caused to flow in contact with a surface of an acid gas remover formed from a mixture including a calcium compound for neutralizing said acid gases, and a binder for holding together particles of the calcium compound. Also disclosed is an incinerator incorporating the acid gas remover.