Abstract: Apparatus (10) and a method for removing volatile organic contaminants from particulate material utilizes a particulate material processor (12) and an emissions processor (14) which includes a recirculating emissions pretreatment circuit (16) and a final treatment system (18). The recirculating emissions pretreatment circuit (16) has an inlet (72) that receives the contaminated hot gas emissions from a heating unit (20) of the material processor (12) and also has a condenser (76) that is preferably embodied by a wet scrubber (88) for removing condensible gases from the emissions prior to passage through an outlet (78) thereof back to the heating unit (20). An inlet (82) of the final treatment system (18) has a fan (48) that draws off a portion of the pretreated emissions for a final treatment. This final treatment may be provided either by a flame burner that is most preferably a part of the heating unit of the particulate material processor (12) or by a carbon adsorber (144).

Abstract: The method for reducing the nitric oxide concentration in the waste gas flow of combustion processes consists of the introduction of chemicals, e.g. ammonia, sal ammoniac, urea, calcium cyanamide, into the waste gas flow, wherein the waste gas flow is marked by an additional compulsorily produced strong turbulence and the waste gas flow is compressed prior to this turbulence zone. The introduction of the treatment medium is effected shortly before the turbulence zone and the waste gas flow is relaxed and calmed subsequent to the turbulence zone. In order to implement this method, a furnace is provided which comprises a grate and a waste gas flue consisting of an ascending waste gas flue and a descending waste gas flue adjoining the latter. The current flow of the waste gas flow is substantially S-shaped proceeding from the furnace grate to the downwardly directed waste gas flue, wherein the change of direction in the lower area is substantially smoother than in the reversing space.

Abstract: A method and apparatus for the combustion treatment of a toxic gas which forms microparticles by combustion are disclosed wherein the toxic gas is subjected to a combustion treatment in a specific combustion furnace where the combustion gas formed is brought into contact with an aqueous film flowing downwards on the inner wall of the furnace from the upper end portion thereof to the lower end portion thereof or with a cooled surface, and then optionally with aqueous droplets dispersed in the interior space of the furnace. The water captures the microparticles formed by combustion of the toxic gas and is discharged out of the furnace as a mixed flow with the combustion gas thus treated, and optionally the mixed flow is successively treated in a gas-liquid separator.

Abstract: A method of thermally oxidizing a gaseous component, e.g., including one or more volatile organic compounds, is disclosed. This method comprises passing an amount of an oxygen component, a controlled amount of a fuel component and an amount of a gaseous component to be thermally oxidized to a combustion zone to combust the oxygen component and the fuel component, to at least partially thermally oxidize the gaseous component and to form a gaseous effluent; contacting the gaseous effluent in a retention zone at conditions effective to thermally oxidize the gaseous component, and thereby form a flue gas; and controlling the amount of fuel component passed to the combustion zone based on the temperature in at least one of said combustion zone and said retention zone contacting occurs. A thermal oxidation apparatus useful for practicing the present method is also disclosed.

Abstract: A method is described for environmentally sound usage of combustible hazardous waste in an operating rotary kiln. The method is particularly adapted for disposal of solid hazardous wastes, optionally in the form of a blended waste homogenate, packaged in sealable containers. The containers are used as fuel modules and charged into a rotary kiln cylinder where kiln gas temperatures range from about 950.degree. to about 1200.degree. C. to achieve high destruction and removal efficiencies.

Abstract: An in-furnace sorbent slurry injection process for the simultaneous control of SO.sub.2 and NO.sub.x from power plant flue gases is described. An aqueous slurry of limestone or dolomite-doped limestone and a nitrogenous progenitor compound is injected into the furnace at temperatures ranging between 900.degree. C. and 1350.degree. C. Under optimized operating conditions, with urea selected as the nitrogenous progenitor, about 80% of the SO.sub.2 and 90% of the NO.sub.x are simultaneously removed.

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: The slag occurring in the waste burning plant (1) is conducted from the slag exit (6) of the oven, directly into a separator (7) for coarse material and iron. There is no chilling in water. After the coarse cleaning, the slag is heated again by means of hot flue gases from the waste burning oven (1) in a preheating device (8), and then, with the feeding of additional heat, melted in a melting oven (10). Flyash is mixed with the stream of slag before the preheating device (8). The harmful substances vaporizing in the preheating and melting are condensed out of the exhaust gases and recovered. Parallel with the preheating device (8) is arranged a pyrolysis oven (9) which is also heated with a partial stream of hot flue gas from the exhaust channel (3). The pyrolysis gas is used as fuel for producing additional heat in the melting oven (10). All the remaining harmful substances not vaporized enter into harmless compounds in the molten slag or are bound, insoluble by water, in the resultant fused slag.

Abstract: The sulfur trioxide in the combustion gas stream of a power plant is reacted with injected ammonia to produce a solid ammonium sulfate that is captured, and not released to the atmosphere. A feedforward signal indicative of the total mass flow of sulfur trioxide is determined as the product of the measured boiler load and the sulfur trioxide content of the combustion gas, as measured prior to the addition of ammonia. The ammonia mass flow injection rate is preferably at a normal stoichiometric ratio of from about 1.0 to about 1.1 relative to the sulfur trioxide mass flow rate (that is, from about 2.0 to about 2.2 times the molar mass flow rate of the sulfur trioxide), avoiding the production of ammonia bisulfate. The ammonia content of the combustion gas stream is measured downstream of the location at which ammonia is added.

Abstract: Apparatus (10) and a method for removing volatile organic contaminants from particulate material utilizes a particulate material processor (12) and an emissions processor (14) which includes recirculating emissions pretreatment circuit (16) and a final treatment system (18). The recirculating emissions pretreatment circuit (16) has an inlet (72) that receives the contaminated hot gas emissions from a heating unit (20) of the material processor (12) and also has a condenser (76) that is preferably embodied by a wet scrubber (88) for removing condensible gases from the emissions prior to passage through an outlet (78) thereof back to the heating unit (20). An inlet (82) of the final treatment system (18) has a fan (48) that draws off a portion of the pretreated emissions for a final treatment. This final treatment may be provided either by a flame burner that is most preferably a part of the heating unit of the particulate material processor (12) or by a carbon adsorber (144).

Abstract: Method and apparatus for treating waste materials to produce aggregates wherein pellets comprised of a mixture of solids, liquid wastes and clay are dried by hot air in a dryer. The pellets are then fed to the pyrolysis zone of a rotary kiln wherein they are heated by hot gas from an oxidation zone of the kiln to drive off most of the volatile gases. Remaining volatile gases and the fixed carbon in the waste are oxidized in the oxidation zone, and the silicates in the clay are vitrified in a vitrification zone of the kiln to produce aggregates which are crushed and screened. Volatile gases given off from the pyrolysis zone are mixed with exhaust gases from the dryer to feed the burner for the vitrification zone and to supply oxygen to the oxidation zone.

Abstract: Unburned particulate matter is removed from a combustion gas stream by adding a conditioning agent to modify the resistivity of the particulate matter and passing the conditioned combustion gas stream through an electrostatic precipitator whose precipitating elements are energized with an intermittent applied voltage. The addition of conditioning agent and the precipitating voltage signal are mutually optimized. A controller receives measurement signals from sensors that monitor the total flow rate of particulate matter in the gas stream before the electrostatic precipitation treatment, and the concentration of particulate matter in the gas stream after the treatment. Performance of the system may be optimized according to selected combinations of variables.

Abstract: An apparatus for incinerating waste material and for reducing noxious byproducts of the incineration process. The apparatus consists of a furnace having a turbulent reaction zone whereby an overfire air header and additive distributor and lime injection nozzles connected to the incinerator through a plurality of nozzles located at even distances about the arrangement is the turbulent reaction zone of the furnace such that an additive mixture is injected into the turbulent zone through and distributed evenly during combustion across the entire width of the turbulent area. As a result, a reaction between the combustion products and the additive is optimized resulting in an overall reduction in acid gas content, acid dewpoint temperature and the corrosion levels inside the incinerator and auxiliary equipment.

Abstract: Apparatus and method for converting refuse to thermal energy, metal, and slag devoid of particulate matter. The refuse is injected into an ignition chamber to ignite readily burnable material. The unburnable material is past to a primary chamber wherein it is exposed to a molten metal bath and to pure oxygen to reduce the unburnable material to metal and slag. Water in the refuse reacts with carbon to produce hydrogen gas. This gas is passed to a secondary chamber wherein the hydrogen is burnt, resulting in an increase in temperature to above 3000.degree. F. and producing water. Because of this high temperature the water disassociates into hydrogen and oxygen. The hydrogen burns repeatedly and forms water and hydrogen in rapid succession generating thermal energy devoid of particulate material. The method and apparatus are also suitable for burning coal instead of refuse.

Abstract: For the production of a product which can be dumped or utilized, the mineral substances are subjected in a rotary kiln to a thermal treatment at a temperature at which the charge of the rotary kiln is transformed to a pasty to liquid slag phase. The composition of the charge is so selected that a slag phase is produced in which the main components, which constitute a matrix, are in the range from 60 to 72% SiO.sub.2, 10 to 30% Al.sub.2 O.sub.3 and 5 to 25% CaO+MgO, of said matrix, wherein the total percentage of SiO.sub.2 +Al.sub.2 O.sub.3 +CaO+MgO equals 100, the total of the main components SiO.sub.2, Al.sub.2 O.sub.3, CaO and MgO amounts to more than 60% on a dry and ignition loss-free basis, of the mineral matter which is charged to the rotary kiln. The slag phase discharged from the rotary kiln is cooled and the exhaust gas from the rotary kiln is purified.

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 the conventional incineration of solid waste materials, flyash present in the combustion products gas stream catalyzes the formation of toxic dioxins from chlorinated organic materials. By providing a catalyst poison, such as carbon disulphide, in association with the flyash, typically by spraying onto the solid wastes prior to incineration, the catalytic effect is decreased, resulting in decreased dioxin formation.

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: A fluidized bed reactor and a method of operating same in which a bed of particulate material is supported on a grate in an enclosure. Air is passed through the grate to fluidize the particulate material and promote the combustion of the fuel. At least one separating unit is disposed adjacent each of two walls forming the enclosure for receiving the mixture of air, the gaseous products of combustion and the relative fine particulate material entrained by the air and gaseous products of combustion. Each separating unit operates to separate the particulate material from the mixture, and a distributor unit is associated with each separating unit for receiving the separated particulate material and distributing it to the bed at multiple locations.

Abstract: A method for collecting condensate includes filling a cylindrical container with a column of coarse sand and mounting the container coaxially to the output end of a furnace conduit through which heated gases containing sublimate will pass. A layer of gas permeable material holds sand in position and an aperture in its center assists in directing gases generally to the center of the sand column. The sand column is spaced away from the furnace a distance such that the temperature differential will cause condensation of the heated gases on the surfaces of the sand particles.

Abstract: Solid residues arising from the burning of solid wastes have lead and cadmium sufficiently insolubilized to pass the EPA toxicity test only where the pH in the EPA test is between 7.5 and 12.0. Addition of water soluble phosphate, especially phosphoric acid, increases the immobilization of lead and cadmium so as to make such residues in compliance with the toxicity tests over a substantially broader pH range.

Abstract: A method for destroying organic explosives, such as RDX and HMX, by hydroolysis comprises contacting liquors containing waste explosive, produced in the manufacture and processing of the explosives, with hydrogen in the presence of a heterogeneous hydrogenation catalyst, such as nickel-on-kieselguhr, for a sufficient period to destroy the explosives. The method is simple and economic and destroys the explosives, which are considered to be toxic, hazardous and non-biodegradable in soil and hence are not amenable to landfill or discharge into rivers etc., thereby eliminating or reducing the attendant pollution problems to acceptable levels.

Abstract: A method of processing radioactive waste resin by pyrolyzing radioactive waste ion exchange resin generated in a nuclear plant such as a nuclear power station. First, the ion exchange resin is pyrolyzed at a low temperature, and the resulting decomposition gas is separated. Second, the ion exchange resin at a high temperature, and the resulting decomposition gas is separated. Finally, the residue of the ion exchange resin is hot-pressed into a molded article.

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 method for processing spent radioactive ion exchange resin formed in a nuclear power plant by a two-step pyrolysis method. First, the spent resin is heated at 350.degree. C. to decompose functional groups selectively. Then the base polymer, formed as residue, is decomposed at a temperature above 350.degree. C., e.g. 600.degree. C. After the thermal decomposition, exhaust gases which require a special exhaust gas disposal means, such as NO.sub.x and SO.sub.x can be reduce to below 1/20.

Abstract: A bed of high-sulfur coal is burned in transit through a furnace on a horizontal or inclined travelling grate. Low pressure air is fed upwardly through the bed in quantities sufficient to react with most of the carbon content of the coal, from which sulfureous gases arise. High pressure air is blasted upwardly through the remnants of the burning coal as they fall off the end of the grate run. Clinker content of the residue free-falls off the end of the grate run into a collector while burned or partly burned fines are elevated above the end of the grate run. High pressure air with entrained limestone blows the elevated particles back through the sulfureous atmosphere above the bed so as to react with the carbon content of the particles and grab the sulfur.

Abstract: A process for the purification of flue gas generated during the combustion of waste materials has a first embodiment wherein soluble heavy metals are precipitated and recovered in a compact form and wherein the soluble heavy metal-free extraction residue is returned to the combustion system where noxious organic substances are pyrolyzed. In another embodiment, substantially all of the heavy metals from the flue gas are collected in a single solid residue, which residue may be thermally treated to recover mercury and the treated residues subsequently returned to the combustion system wherein noxious organic substances are pyrolyzed or combined in a hazardous waste stabilizing substance.

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: A process is provided for combusting sulfur-containing coal in a combustion stage to which is provided at least 60% of the oxygen stoichiometrically required for substantially complete combustion of the coal and combustion is conducted under highly turbulent conditions in a furnace burner cavity to which finely divided iron oxide and/or iron powder is provided and in which a high heat release rate is maintained to form a liquid iron oxysulfide phase which acts to scrub sulfur-containing gaseous species from the combustion atmosphere and is separated from the combustion atmosphere with substantially the sulfur originally contained in the coal. Following separation, the hot fuel gas resulting is burned to completion in a heat exchanging furnace, gas turbine or other energy extracting device.

Abstract: A fluidized bed reactor and a method of operating same in which three discrete chambers are formed in a housing and a main fluidized bed containing particulate fuel and adsorbent material is established in a first chamber. The fluidizing air in the first chamber entrains a portion of the particulate material as it passes through the bed and the first chamber. A portion of the particulate material that is entrained by the air is separated and introduced to additional grid means disposed in a second chamber to establish a bed of the separated particulate material. Air and a cooling fluid are passed through the bed of separated particulate material for cooling same. The cooled separated particulate material is passed to a third chamber for storage and the latter is connected to the main fluidized bed for selectively reinjecting the cooled separated particulate material back to the main fluidized bed.

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: This invention relates to an improved method of controlling temperatures within a cleaning or reclamation furnace which is normally used to reclaim metal parts contaminated with combustible materials by pyrolyzing the combustible materials. A reclamation furnace usually includes a primary heat-input burner employed to heat the contaminated parts in the primary heating chamber, an afterburner chamber contained within the heating chamber having a secondary burner to burn volatile gases which are given off by the combustible materials as the parts are heated, and two separately-controlled automatic valve and spray nozzle assemblies connected to the primary heating chamber. Each nozzle assembly is connected to a pressurized water source to deliver a water-spray injection into the heating chamber.

Abstract: A fluidized bed combustor is utilized as a source of drains, including spent calcium-based sorbent. The reacted sorbent is broken to expose unreacted portions which can be recycled to capture additional sulfur compounds. A separation is provided by a magnetic separator and an electrophoretic separator in order to obviate the load of recycling reacted sorbent and other waste material having no calorific value.

Abstract: Burning a waste fuel blend at very high temperatures (typically greater than 4000 deg. F.) for a very short period of time (typically a matter of milliseconds) in a primary combustion zone to break the complex hazardous/toxic hydrocarbons into less complex chemicals (such as CO, CO.sub.2, H.sub.2, OH, HCl, and Cl.sub.2), passing the products of the primary zone into a secondary zone in which the products are maintained for a longer time (typically about 2 secs.) in turbulent conditions with excess air at lower combustion temperatures (typically 2000 to 2600 deg. F.) to reduce the primary zone products to a mixture of H.sub.2 O, CO.sub.2 and acids such as HCl, and quenching the products of the secondary zone.

Abstract: A method of operating a fluidized bed in which a bed of particulate combustible material and adsorbent material are disposed on a perforated plate. Air is introduced through said plate and into said bed to fluidize and promote the combustion of the combustible material, and a gaseous agent is injected into the bed to stabilize the surface hardness, sulfur-absorption properties and catalytic properties of said adsorbent material.

Abstract: A method and apparatus for combustion of a sulfur-containing fuel which substantially reduces the amount of gaseous sulfur compounds which would otherwise be emitted.A source of oxygen, a sulfur-containing fuel, and an inorganic alkaline absorbent are reacted under controlled conditions of temperature, stoichiometry, and residence time whereby the inorganic alkaline absorbent reacts with the fuel sulfur to form a mixture of combustion products and desired solid sulfur compounds, the latter being readily removed utilizing conventional filtration equipment. In a preferred embodiment of the invention, the mixture of fuel and combustion products is passed into a nitrogenous compound destruction zone wherein, under controlled conditions, the concentration of nitrogenous compounds present are reduced to a desired level.

Abstract: A waste material incineration system (10) and method of combusting waste material is provided wherein system (10) includes a longitudinally directed furnace (14) having a first combustion zone (42) and a second combustion zone (44). Waste material or other fuel is inserted into furnace (14) through a furnace inlet (26) and passes by gravity assist into a vortexing pattern dependent upon the geometrical contouring of the internal walls of furnace (14) in combination with preheating air conduits (86, 88 and 90). Subsequent to vortexing in the first combustion zone (42), the substantially fully combusted gases are transported through second combustion zone (44) for insert into a heat exchanger unit (12) and then passes to a scrubber unit (34) where the exhausted gases are further cleansed to expulsion of the cleansed exhaust gases through an exhaust stack (16) to the ambient atmosphere.

Abstract: A method of ameliorating high-temperature slagging conditions which result from impaction on the boiler interior surfaces of molten or semi-molten ash particles in flue gas resulting from the combustion of fuel. The method comprises adding a conditioner to the flue gas at or upstream of the high temperature region in the boiler system where slagging tends to occur, and thereafter causing the mixed flue gas and conditioner to flow through the region. Suitable conditioners include strontium carbonate, a mixture of zircon with copper oxychloride and a mixture of alumina with aluminum fluoride, zircon, or zirconyl chloride.

Abstract: A fluidized bed combustion system for burning fuel particles, such as coal. The system includes a housing defining a first combustion region. An endless, flexible, perforate belt is shiftably mounted in the housing for supporting coal particles of relatively large size. A blower below the belt creates fluidized air which entrains smaller coal particles in a fluidized bed above the larger coal particles. The combustion gases arising due to combustion of the coal particles passes through a secondary combustion region in which coal fines are burned. The combustion gases continue upwardly through a scrubber in which limestone particles are entrained in the combustion gases to strip sulfides therefrom. The limestone particles are regenerated by a cyclone separator while the combustion gases travel through a passage containing boilers or other heat exchangers, whereby the heat from the combustion gases is transferred to fluids in the boilers.

Abstract: The products of a molten salt combustion of hazardous wastes are converted into a cooled gas, which can be filtered to remove hazardous particulate material, and a dry flowable mixture of salts, which can be recycled for use in the molten salt combustion, by means of gas/liquid contact between the gaseous products of combustion of the hazardous waste and a solution produced by quenching the spent melt from such molten salt combustion.The process results in maximizing the proportion of useful materials recovered from the molten salt combustion and minimizing the volume of material which must be discarded. In a preferred embodiment a spray dryer treatment is used to achieve the desired gas/liquid contact.

Abstract: In the combustion of high sulfur coal, SO.sub.x emission is reduced by pyrolizing the coal in a reducing atmosphere to form char and convert the sulfur compounds to combustible gases including H.sub.2 S. The H.sub.2 S is reacted with the coal and the char to produce ash containing sulfur which is easily removed from the combustion process. A three zone furnace includes a zone in which the coal is pyrolized in a reducing atmosphere to convert the sulfur compounds to combustible gas which reacts with the coal and char.

Abstract: A method of treating reaction products which result from the combustion of fuels containing contaminants such as sulfur, chlorine, and fluorine compounds, and ash. Additives are reacted in the combustion chamber with gaseous contaminants of the reaction products of the combustion. Subsequently, the remaining reactive additives, the reactive ash constituents, and possibly supplementary additives are reacted externally of the combustion chamber with the still uncombined gaseous contaminants of the reaction products.

Abstract: A method for processing rice wherein paddy rice is heat treated, the heat treated rice is shelled to separate the hulls from the brown rice, the hulls are fed into a burner unit wherein they are burned in two stages to produce ash and relatively clean hot gases, and the hot gases are cycled for use in the heat treating phase.

Abstract: The instant invention is directed to a process for lowering the electrical resistivity of fly ash comprising adding a cationic or anionic polymer to the fly ash.

Abstract: A technique for raising slag fusion temperatures is provided whereby fouling deposits can be reduced. The technique involves mixing with slag or slag precursers phosphated alumina perferably in a liquid form for convenience in application.

Abstract: A process for cleaning surfaces of installations fouled by products of combustion of carbon-bearing materials, such as in particular boiler combustion chambers, rotary or static heat exchangers, combustion product ducts and flues, electrostatic filters, etc., which are to be cleaned without having to stop the combustion process, in order to maintain maximum thermal efficiency in order thereby to make a substantial energy saving, in which an aqueous solution of ammonium nitrate and potassium nitrate is injected into the installation, the deposited substances being detached from the installation by means of sound sources.

Abstract: A method and composition are described for carrying out the combustion of fossil fuels in a fluidized bed with reduced emissions of sulfur, carbon and nitrogen oxides and unburned hydrocarbons. Combustion is carried out in the presence of a solid sulfur oxide adsorbent and a metal or metal oxide component which is catalytically active with respect to unburned hydrocarbons, carbon monoxide and nitrogen oxide.

Abstract: Solid fuel such as coal is fed into an inlet shaft of the furnace through a rotary feeder constructed to prevent the admission of air. Primary air channels supply the major part of the air required for combustion of the fuel in a region in which the fuel bed is sufficiently thick to avoid disturbance and the formation of "holes" by this air. Further, narrower air channels supply sufficient, diffused and low velocity air to complete the combustion of the fuel without substantial entrainment of grit and ash. Air is prevented from flowing in contact with the fuel up stream of the primary channels and the metering edge.

Abstract: A solid fuel boiler or furnace with a flue gas-air mixture introduced into the fuel grate is disclosed. The flue gas is mixed with air such that approximately 30% of the mixture is flue gas. By providing this mixture under the burning fuel bed, the temperature of the fuel bed is lowered and excess oxygen is reduced. A more reactive fuel bed results providing various advantages including improved boiler operation and a clinker-free fuel bed.

Abstract: To a coal-fired furnace that uses electrostatic precipitation or a mechanical collector to collect fly ash, a mix of magnesia-alumina or magnesia-talc is added above the fireball (2600.degree.-3300.degree. F.). The additive increases the mean particle size of the fly ash and reduces its surface resistivity, thereby causing improved collection in the electrostatic precipitators or mechanical collector. Fine particulates containing heavy metals tend to be agglomerated; thus the invention permits recovery of substantial amounts of heavy metal contaminants that would otherwise be lost as stack emission.