Abstract: An improved method for burning carbonaceous material containing sulfur to reduce emissions of SO.sub.2 is disclosed wherein the carbonaceous material is projected into a furnace as one or more streams and each stream is continuously ignited with a volatile fuel such as natural gas, oil, liquefied petroleum gas or naptha. The volatile fuel is supplied separately from the carbonaceous material and is directed into each stream of the carbonaceous material as it enters the furnace so as to cause the material to be enveloped in a reducing atmosphere during its volatilization. In consequence, at least a portion of the sulfur contained in the carbonaceous material is retained within the ash slag in its reduced or sulfide form.

Abstract: A method of cooling ashes and bed material when discharging the material via an ash chamber (20) in or near a combustor burning a fuel in a bed (28) of particulate material. Cooling gas is introduced into the ash chamber (20) via a gas distributor (70), is allowed to pass through a material layer (21), is discharged via a collecting device (76) and is circulated through a cooling circuit (69) with a cooler (82) by a compressor or fan (88). The invention also relates to a power plant in which the method is utilized.

Abstract: A power plant burning a fuel, primarily coal, in a bed vessel with a fluidized bed of a particulate material at a pressure exceeding atmospheric pressure. Consumed bed material and/or ashes separated from combustion gases are removed through a pressure-reducing discharge means. A part of the pressure-reducing discharge means is located in a dryer for crushed coal which forms a bed arranged as a bed vessel where crushed coal to be dried forms a fluidizable bed. The bed is fluidized by gas introduced through nozzles in the bottom of the bed vessel. The discharge portion constitutes a heater for the bed and a cooler for the discharge portion.

Abstract: A power plant with combustion of a fuel at a pressure exceeding the atmospheric pressure in a fluidized bed (14) in a bed vessel (12) which is enclosed within a pressure vessel (11). The space (37) between the pressure vessel (11) and the bed vessel (12) is supplied with combustion air from a compressor (22). Ash and consumed bed material are taken out from the bed vessel (12) via an ash chamber (34) and are cooled therein by air from the space (37). The air from the space (37) is cooled in a cooler (44) before being supplied to the ash chamber (34).

Abstract: A cyclone used for high temperature cleaning of combustion gases from a PFBC power plant is formed with an elongated leg surrounded by a jacket forming a cooling channel around the leg. Compressed combustion air cools the cyclone leg to a temperature at which the material from which it is made has a satisfactory strength and resistance to wear. Air for additional cooling of ash separated in the cyclone can be supplied at a downstream orifice of the cyclone leg.

Abstract: An improved reinjection system is described for a bubbling bed fluidized bed combustor of the type having a combustion zone in which fuel is burned in a fluidized bed of granular material, means for collecting particles from the flue gases and means for reinjecting the collected particles into the combustion zone. The improved reinjection system comprises a first particulate material conductor pipe sloping downwardly toward the combustion zone, the lower end of this first downwardly sloping pipe being flow connected by way of a lower corner or elbow to a short section of upwardly sloping pipe. The upper end of this short upwardly sloping pipe is flow connected by way of an upper corner or elbow to a second downwardly sloping pipe. The first downwardly sloping pipe, the upwardly sloping pipe and the second downwardly sloping pipe form therebetween a Z-valve.

Abstract: A power plant with combustion of a fuel in fluidized bed (21) of particulate material, usually contains a sulphur absorbent. A bottom (14) divides a bed vessel (12) into an upper combustion chamber (15) and a lower conical or pyramid-shaped ash discharge chamber (16) for discharging ashes and consumed bed material. The bottom (14) is formed with openings (22) through which material is able to pass. Cooling air is supplied to the lower part of the lower chamber (16). This chamber (16) is provided with grates (37, 38) with horizontal channels (46) for spreading cooling air from the central part of the chamber (16) to its outer parts. These grates (37, 38) may be formed of U-sections with their openings facing downwards. The channels (46) of a grate (37) may be connected to the combustion chamber (15) by vertical tubes (50).

Abstract: A system for discharging and cooling hot ash from a coal combustion unit, such as a coal combustor or an associated filter, where the hot ash at a temperature in excess of 700.degree. C. and at superatmospheric pressure is charged to a jacketed, cooled screw conveyor and passed therethrough in contact with a countercurrent flow of a purge gas. The ash is cooled in the screw conveyor to a temperature of below 320.degree. C. and dischaged to a collection hopper, under pressure, while the purge gas and gases evolved from the hot ash are returned to the combustion unit.

Abstract: A stoker assembly for a solid particulate burning stove that includes a fuel directing flange for directing the fuel to an upper combustion plate and ventilation tubes to prevent the ignition and combustion of fuel stored in remote bins. The fuel directing flange serves to prevent the solid particulate fuel from falling back into the auger conveyor and being ground into smaller particulate matter.

Abstract: A method and system for controlling the cyclone collection efficiency and recycle rate in a fluidized bed reactor in which air is introduced into the cyclone separator in a direction opposite to that of the flow of the flue gases and entrained solids. The air entrains a portion of the fine solids and passes same through the separator and to a heat recovery area to reduce the solid inventory reduction as needed.

Abstract: In a coal combustion system suitable for a gas turbine engine, pulverized coal is transported to a rich zone combustor and burned at an equivalence ratio exceeding 1 at a temperature above the slagging temperature of the coal so that combustible hot gas and molten slag issue from the rich zone combustor. A coolant screen of water stretches across a throat of a quench stage and cools the combustible gas and molten slag to below the slagging temperature of the coal so that the slag freezes and shatters into small pellets. The pelletized slag is separated from the combustible gas in a first inertia separator. Residual ash is separated from the combustible gas in a second inertia separator. The combustible gas is mixed with secondary air in a lean zone combustor and burned at an equivalence ratio of less than 1 to produce hot gas motive at temperature above the coal slagging temperature.

Abstract: Coal combustion and the capture of pollutants are optimized by a method which applies two mechanisms for sulphur capture, one in which pulverized coal particles suspended in the gas stream in the injection zone of the combustor are affected by reaction with a suspended sorbent, and another in which the particles are reentrained in the gas stream by a "sand storm" effect near the wall of the combustor. Use of the two mechanisms results, in commercial scale cyclone combustors, in 70 to 90% sulphur capture at economical Ca/S ratios. The method also minimizes emission of ash by removal from the pulverized coal fuel particles too small to be retained in the combustor and too large to be completely burned in the combustor, minimizes reevolution of sulphur compounds from slag by rapid and continuous removal of slag from the combustor, minimizes emission of NO.sub.x pollutants by maintaining a favorable overall fuel-rich stoichiometry.

Abstract: A method and apparatus for calcining limestone to produce lime wherein coal is combusted to provide heat for the calcination. The coal is combusted in a two stage combustion unit, with at least seventy-five percent of the slag formed by the coal combustion removed from the first stage of the combustion unit. Residual gases and fuel are further combusted in the second stage of the two stage combustor, with hot combustion gases therefrom, having the molten slag removed, fed directly to the calcining chamber of a rotary lime kiln. The coal may be carbonized to form a char and a fuel gas for use in the two stage combustor.

Abstract: An ash removal apparatus for an incinerator. The combustion chamber of the incinerator is provided with a longitudinally extending bottom trough and a pair of endless chains are mounted to travel in longitudinal grooves in the sides of the trough. A plurality of cleats connect the chains and the cleats extend only along a portion of the length of the chains so that during the combustion process, the cleats are not located in the combustion chamber where they would be exposed to the intense heat of combustion to remove ash, the chains are operated to move the cleats along the trough to convey ash out of the combustion chamber to a discharge site.

Abstract: There is provided a slagging coal combustion system suitable for retrofitting boilers, furnaces and industrial-process heat generators originally designed to burn oil or gas. It comprises a primary combustion chamber into which oxidizer and fuel are injected to provide high-velocity, rotational-flow combustion zones, such that the fuel is burned substoichiometrically, while in flight, with up to 90% of the resultant ash being removed as molten ash. The combustion products pass from the primary chamber to chamber where slag is removed and the gaseous products are passed to end-use equipment. A coal-fired precombustor subsystem feeds partially-heated air as the oxidizer to the primary combustion chamber supply of oxidizer, at any selected temperature within the range from about 1200.degree. F. to about 2000.degree. F. The stoichiometry of this precombustor and the velocity and mass-flow rates of its output stream are independently controllable.

Abstract: A vessel having a floor which includes a tap outlet through which liquid contents in the vessel can be drained. The tap outlet features a shallow aperture circumscribed by first and second drip lines. The second drip line circumscribes the first drip line and is substantially coplanar with the first drip line. The two drip lines are connected one to the other by an annular hollow surface.

Abstract: An air-cooled cyclone coal combustor comprises a horizontally disposed shell, provided with a non-sacrificial refractory liner. The liner is surrounded by an array of air-cooling tubes, the tubes serving both to cool the liner and to physically support and reinforce it. Air cooling in the manner disclosed facilities precise control of the thickness and flow of slag on internal walls of the combustor, so as to avoid reevolution from the slag of the sulfur pollutants. Pulverized coal fuel and a pulverized sulfur sorbent (limestone or the like), as well as primary and secondary combustion air, are introduced into the chamber at an end wall. The cooling air, heated regeneratively in the cooling tubes, provides the secondary air, and is introduced in the chamber in helical flow, at a radius outwardly from the radius at which the solids and primary combustion air are introduced into the chamber. A thermally insulated nozzle provides an outlet for combustion gases.

Abstract: Sulfur-containing coal is combusted in a cyclone furnace under strongly reducing conditions with a sulfur fixing agent such as lime to produce a basic slag containing the ash and sulfur content of the coal and a product gas of high combustible content which may be burned as a fuel gas in a steam generator or otherwise to yield an exhaust gas which does not require scrubbing.

Abstract: A combustor for burning a feedstock includes a cylindrical body having a tangential feedstock inlet and an exhaust outlet. A catchment chamber of hollow cylindrical form intersects the wall of the body and opens into the cavity to provide a common boundary. Swirling or vortical flow is created in the cavity and a secondary vortex is generated and driven within the chamber by the main flow. In operation contaminant matter is sheared off from the flow in the body into the chamber and is entrapped by the secondary vortex from which it is precipitated, there being no net gas flow across the boundary.

Abstract: A system for recovering resources from sludge in which sludge containing water in the amount of 90 to 70 percent is first supplied to a sludge concentrator through a forced supply equipment where the sludge is concentrated to contain a water content of a maximum of about 60 percent; then is sent to a drying furnace having a fluidized sand bed. The product obtained in the drying furnace is separated to gas and solid. After the separated gas is pressurized by a fan and is heated by a heat exchanger through a circulator passage, a portion thereof is supplied to the drying furnace as gas for drying and the remainder is sent to the sludge concentrator. The water content is then removed from the concentrated gas and the gas obtained from the sludge concentrator is used in the system as gaseous fuel.

Abstract: A reaction chamber with a fluidized bed encloses two superposed cyclone separators connected in series. In order to prevent combustion gases from entering the lowermost separator by way of its particulate matter outlet, this is formed as a downwardly extended pipe, which is enclosed by a sleeve through which secondary air passes. The sleeve projects somewhat below the mouth of the pipe, and the issuing air causes an ejector action, which prevents gas from entering the pipe. The particulate matter return flow pipe from the upper cyclone is also extended downwards and terminates within the ejector. A storage vessel is located below the reaction chamber. An open conduit extends from the storage vessel to a location above the fluidized bed. Also, there is a return conduit for returning material from the storage vessel to an area above the fluidized bed. An equalizing conduit connects the vessel with an ejector supplying air to the fluidized bed.

Abstract: A steam generator for burning a normally-solid fuel which produces non-combustible solid residues, including, an elongated combustion chamber, a fuel introduction means to introduce fuel adjacent the axis of the combustion chamber as a centrally-disposed stream moving in a downstream direction, a combustion-supporting gas introduction means for introducing the gas as an annular, rotating stream about the fuel stream and which, together with the fuel introduction means forms a rotating, toroidal vortex of the fuel and the combustion-supporting gas moving in a downstream direction. The combustion chamber has a volume sufficient to burn all of the fuel and, together with the fuel introduction means and the combustion-supporting gas introduction means, cause the vortex to collapse and form plug flow thereafter. Water introduction means introduces water into the flue gas at the downstream end of the combustion chamber as a plurality of peripherally-arranged jets.

Abstract: Various embodiments of apparatus and methods are disclosed for the conversion of steam boilers from being oil fired to coal and natural gas fired without adversely affecting the normal power density of the boilers or the emission pollution therefrom. In some cases even the resultant coal ash can be modified by injecting a powdered catalyst or phosphate slimes into the flame to produce a fertilizer ash having desirable minerals to enhance the economic value thereof.Basically all embodiments include a swirling coal-air mixture directed along a path to form a sheath and a swirling gas-air mixture internally thereof with the swirling of the latter being in the same direction and fortifying the motion of the former. A gas-air mixture, swirling or non-swirling, may be supplied outwardly of such sheath to enhance the more complete burning of the coal-air mixture.

Abstract: A thermal decomposition furnace in which waste tires having original shape, not broken up, can be laid horizontally and be thermally decomposed. The furnace is constructed by providing a feeder above, forming downward a fluidized bed-forming section having inlets for air, forming beneath a sealing bed-forming section of right cylindrical shape having a diameter smaller than that of fluidized bed-forming section, and installing a conveyor below said sealing bed-forming section. At the lower end of sealing bed-forming section, an oblique opening is formed so as to keep an progressively increasing clearance to the conveyor in the direction of advance of conveyor.

Abstract: A thermal decomposition furnace in which waste tires having original shape, not broken up, can be laid horizontally and be thermally decomposed. The furnace is constructed by providing a feeder above, forming downward a fluidized bed-forming section having inlets for air, forming beneath a sealing bed-forming section of right cylindrical shape having a diameter smaller than that of fluidized bed-forming section, and installing a conveyor below said sealing bed-forming section. At the lower end of sealing bed-forming section, an oblique opening is formed so as to keep a progressively increasing clearance to the conveyor in the direction of advance of conveyor.

Abstract: Various embodiments of apparatus and methods are disclosed for the conversion of steam boilers from being oil fired to coal and natural gas fired without adversely affecting the normal power density of the boilers or the emission pollution therefrom. In some cases even the resultant coal ash can be modified by injecting a powdered catalyst or phosphate slimes into the flame to produce a fertilizer ash having desirable minerals to enhance the economic value thereof.Basically all embodiments include a swirling coal-air mixture directed along a path to form a sheath and a swirling gas-air mixture internally thereof with the swirling of the latter being in the same direction and fortifying the motion of the former. A gas-air mixture, swirling or non-swirling, may be supplied outwardly of such sheath to enhance the more complete burning of the coal-air mixture.

Abstract: A reaction chamber with a fluidized bed encloses two superposed cyclone separators connected in series. In order to prevent combustion gases from entering the lowermost separator by way of its particulate matter outlet, this is formed as a downwardly extended pipe, which is enclosed by a sleeve through which secondary air passes. The sleeve projects somewhat below the mouth of the pipe, and the issuing air causes an ejector action, which prevents gas from entering the pipe. The particulate matter return flow pipe from the upper cyclone is also extended downwards and terminates within the ejector.

Abstract: A multi-annular swirl burner includes a plurality of overlapping tubular wall members which form a rich combustion zone and a lean combustion zone with a throat section therebetween. Annular passages are located between adjacent wall members, and vanes located therein input a tangential velocity to entering air. The tangential velocity of the swirling flows increases with increasing radius to produce centrifugal separating force on particulates moving from the rich combustion zone to the throat section. A collection system scavenges particulates from the throat section for disposal.

Abstract: A solid fuel burner comprises a system which permits solid fuel to be injected into a burner chamber and intermixed in an air suspension. The burner includes a cast iron, stepped grate that is self-cleaning, and comprises a series of plates that are substantially horizontal and are vertically spaced apart to form steps. Air is introduced under the stepped plates and the air blows out into the combustion chamber through the spaces between the plates to aid in combustion and cause turbulence in the fuel introduced. The burner further includes a "pin hole" grate adjacent the stepped grate on which lighter materials will fall and will be also subject to an air stream for complete combustion, and efficient burning.

Abstract: A method for generating steam by a high pressure, high intensity, or high heat release method of combustion in an elongated combustion zone having upstream and downstream ends and an intermediate location and utilizing a normally-solid fuel which produces non-combustible solid residues in which the fuel is introduced axially and a volume of air, at least equal to the stoichiometric amount, is introduced as an annular, rotating stream to produce a rotating vortex of fuel and air, such introduction and flow through the combustion zone being carried out in a manner to collapse the vortex and create plug flow at the intermediate location, burning the fuel and air to produce flue gas at a heat release rate of at least 7 MM Btu/hr, abruptly terminating combustion by the introduction of water, vaporizing the water to produce a mixture of flue gas and steam, and separating solid residues therefrom.

Abstract: A new and improved reciprocating grate system for furnaces and incinerators wherein the system is advantageously constructed to accomplish a variety of objectives. Adjacent flights of adjacent portions of the composite grate structure reciprocate back and forth and the speed and stroke of such reciprocation can be ganged, coupled, or independently controlled. The individual grates themselves are advantageously configured for suitable spreading and air mixture relative to debris advancement. Air seals are provided and batch feed is accommodated. Grate frame reciprocation is accommodated by fluid control means, either hydraulic or pneumatic, and features are provided for enabling appropriate adjustment both of drive and stroke of related individual components.

Abstract: A combustion apparatus for a granular solid fuel, comprising a plurality of horizontal cylindrical combustion chambers serially connected in their axial direction, partitions interposed between the combustion chambers, communication holes pierced through the partitions for passing the combustion gas. To the combustion chambers, air is delivered in directions to cause the gas to flow in a swirled state, allow the granular fuel to be burnt as agitated and fluidized within the upstream combustion chamber, and forward the gas in a swirled state from the upstream to the downstream combustion chamber. The combusted gas, on reaching the extreme downstream combustion chamber is drawn out by means of a gas delivery pipe having one end thereof communicating with the combustion chamber.

Abstract: An ignition burner and a pilot burner form part of an ignition system for a fluidized stream of finely-divided coal particles in a pressurized gasifier housing having a slag overflow pipe coupled to a discharge vessel. A fuel supply pipe delivers fuel for combustion by the ignition burner and the pilot burner. A sparkplug or hot wire is used to ignite the fuel delivered to the ignition burner. The flame produced by the ignition burner is widened by a baffle so that ignition by the pilot burner occurs to produce a flame which is monitored through a thermocouple. The parts forming the ignition system are carried by a pair of levers with pivots on the inner wall of a slag overflow pipe for movement between an operative position wherein the ignition burner is situated near the slag-receiving opening of the overflow pipe and an inoperative position wherein the ignition burner is protected from contact by slag and radiation heating.

Abstract: A process for producing mineral wool having a chemical composition comprised of between about 50 and 70 weight percent silica plus alumina, about 20 and 35 weight percent lime plug magnesia and about 5 and 15 weight percent iron oxides is described.The process includes feeding a first particulate waste material having a particle size of 100 weight percent -200 mesh and containing organic combustibles having heating values of about 10 mega J per kilogram of slag and inorganic non-combustibles, a second particulate waste material having a particle size of 100 weight percent -200 mesh and containing fluxstone, and preheated air at a velocity of between about 30 meters to 60 meters per second at a temperature of about 500.degree. C. into a high temperature cyclone-like furnace. The combustibles are substantially instantaneously burned and the non-combustibles and the fluxstone are melted and reacted to form a molten slag which can be fiberized into mineral wool.

Abstract: A high temperature solids gasification generator which employs finely divided solids, e.g. powdered coal, has a down flow and discharges into a plenum chamber below the generator. The plenum chamber has a restricted outlet at the bottom so that a pool of liquid slag will form, and there is a lateral outlet above the slag pool for effluent gas. The lateral outlet has its throat located offset farther from the axis of the plenum chamber than the inside radius of the chamber.

Abstract: Pellets to be fired are treated with high-temperature gases which, before being supplied to the pellets, are heated by combustion of fuel in a combustion chamber to a temperature above the temperature at which the pellets are to be treated and high enough to ensure that slag formed during combustion can be tapped in liquid form. Cooler gases are then admixed to the high-temperature gases outside the combustion chamber and before they are supplied to the pellets to cool the gases to the temperature desired for the treatment.

Abstract: Structure for slag removal from a gasification generator. It employs a duct through the bottom that carries through it products of the combustion which is being carried out in the generator. The dimensions are such that the slag which adheres to the walls remains liquid and drips from the bottom edges. The duct is enlarged by at least one step with the length and width of it related to the upper portion of the duct so that the bottom edges of the step are above a diagonal of the upper portion extended.

Abstract: Method and apparatus for removing ash formed within, and accumulated at the lower portion of, a fluidized bed coal gasification reactor vessel. A supplemental fluidizing gas, at a temperature substantially less than the average fluidized bed combustion operating temperature, is injected into the vessel and upwardly through the ash so as to form a discrete thermal interface region between the fluidized bed and the ash. The elevation of the interface region, which rises with ash accumulation, is monitored by a thermocouple and interrelated with a motor controlled outlet valve. When the interface rises above the temperature indicator, the valve opens to allow removal of some of the ash, and the valve is closed, or positioned at a minimum setting, when the interface drops to an elevation below that of the thermocouple.

Abstract: A gas generator for operation on a fuel of fine-grained coal which includes a steam boiler, a combustion boiler and a stack leading from the combustion. chamber to the steam boiler. The steam boiler is provided with a slanting bottom portion for the discharge of fly ash and slag. The stack from the combustion chamber to the boiler is composed of a gas outlet pipe attached to the combustion chamber and a gas inlet pipe leading to the boiler. The gas outlet and gas inlet pipes are connected by attaching means. The gas inlet pipe has a double wall of which the inner wall with its top extends freely into the slanting bottom portion of the boiler and thus is adapted for axial heat expansion. The outer wall is provided with a heat expansion compensator and is connected with its top end to the said slanting bottom of the boiler and with its bottom end to the connecting means between the gas inlet and gas outlet pipes. The inner wall of the gas inlet pipe may be in the form of a jacket for holding a cooling water.

Abstract: A continuous process for the combustion of solid fuels in the presence of an aqueous liquid phase under conditions such that oxides of nitrogen are not formed and oxides of sulfur and particles of ash are effectively prevented from contaminating the gaseous products released to the atmosphere. Fuel is charged as a slurry in alkaline aqueous solution and contacted with combustion air so that the catalytic properties of both water and alkali operate to permit rapid and complete combustion at comparatively low temperatures. Temperatures in the adiabatic reactor are, however, permitted to exceed the critical temperature of the liquid phase. Under the conditions of the process, formation of nitrogen oxides is negligible, sulfur in the fuel goes to sulfur trioxide which dissolves completely in the alkaline liquid phase which also retains particles of ash and unburned fuel. The resulting flue gas is essentially free from objectionable pollutants.

Abstract: A fluidized bed coal reactor includes a combination nozzle-injector ash-removal unit formed by a grid of closely spaced open channels, each containing a worm screw conveyor, which function as continuous ash removal troughs. A pressurized air-coal mixture is introduced below the unit and is injected through the elongated nozzles formed by the spaces between the channels. The ash build-up in the troughs protects the worm screw conveyors as does the cooling action of the injected mixture. The ash layer and the pressure from the injectors support a fluidized flame holder combustion zone above the grid which heats water in boiler tubes disposed within and/or above the combustion zone and/or within the walls of the reactor.

Abstract: Pyrolyzing pulverized coal to form char and volatiles, separating the char from the volatiles, burning the char in heat-transfer relationship with a stoichiometric excess of air, forming thereby ash and a mixture of gases, the excess of air being chosen to produce in the ash a temperature below the fusion temperature thereof, separating the mixture of gases from the ash, and thereafter burning the volatiles in the mixture of gases.

Abstract: An easily removable unit connecting a pressurized gasifier vessel with a slag quenching chamber, wherein the unit consists of a flanged cylindrical tube arranged to carry the slag tap, burner and all services, supplies, electrical cables to and from the gasifier.

Abstract: In a slagging gasifier the slag quenching chamber is provided with means having a plurality of equispaced outlet ports disposed around the inside of the upper region of the chamber, each outlet port communicating with a venting control which may be used selectively to vent the normally pressurized quenching chamber to atmosphere during a slag-tapping operation.