Abstract: A fuel-staging burner assembly and method in which a burner nozzle has separate, concentrically disposed elements to burn coarse and fine coal particles under different combustion conditions to reduce the production of nitrogen oxides from the combustion of coal as a fuel. The burner assembly further includes a control nozzle for maintaining a swirling motion in the combustion flame and a separate, axially-movable adjustable sleeve for regulating the quantity flow of turbulence-free combustion-supporting air.

Abstract: A fluidized bed heat exchanger in which air is passed through a bed of particulate material containing fuel disposed in a housing. A steam/water natural circulation system is provided in a heat exchange relation to the bed and includes a steam drum disposed adjacent the bed and a tube bank extending between the steam drum and a water drum. The tube bank is located in the path of the effluent gases exiting from the bed and a baffle system is provided to separate the solid particulate matter from the effluent gases. The particulate matter is collected and injected back into the fluidized bed.

Abstract: The method of burning different sorts of solid fuel in a tunnel-like burner furnace comprises the steps of pulverizing the solid fuel particles to a size corresponding to optimum burning performance of the employed burners, supplying the pulverized particles in an air stream to the burners of the furnace and adjusting the supplied amount of pulverized particle-air mixture, and the amount of air in the mixture in accordance with the optimum burning performance of the burner. The burner furnace system for performing the method of this invention comprises a tunnel burner furnace having a plurality of ceiling burners and of side wall burners, a fuel distributor having a rotatable distributing channel communicating successively with respective burners and a dosing device connected to the input of the fuel distributor and adapted for adjusting the stream of the mixture of air with pulverized fuel particles.

Abstract: A vapor generator in which a plurality of vertically aligned fluidized beds are disposed in a furnace section with one of the boundary walls of the furnace section having openings therein for permitting the discharge of effluent gases from the fluidized beds. A heat recovery enclosure is formed adjacent said furnace section and shares a common wall with the furnace section for receiving the effluent gases, and a convection enclosure is disposed adjacent the heat recovery enclosure and shares a common wall with the latter enclosure for receiving the effluent gases from the heat recovery enclosure. The boundary walls of the furnace section, the heat recovery enclosure and the convection enclosure are formed by a plurality of interconnected tubes through which fluid is passed in a predetermined sequence to transfer heat from the fluidized beds to the fluid.

Abstract: A method of operating a pulverized coal furnace wherein the coal is introduced with minimal oxygen through an intermediate zone of the furnace which also has a relatively low oxygen content. The carbon particles are projected into an upstream portion of the furnace where secondary air is introduced to burn the carbon particles. The combustion products pass upwardly through the intermediate zone to a downstream zone where tertiary air is added to complete combustion.

Abstract: An individual cell of a fluidized bed includes a static bed disposed immediately below the fluidization region with a coal feed system, which incorporates means for igniting the coal, embedded within the static bed. Coal is fed to the static bed through a coal pipe which extends vertically upward through the bed support plate into said bed and which terminates therein in a coal distributor having a series of openings around its circumference. The coal is swirled as it flows upward through the coal pipe with resultant centrifugal force imparted to the coal ensuring that the coal will be propelled out of the openings in the distributor head and evenly distributed over the cell area.

Abstract: A method and associated apparatus for carrying out fluidized bed combustion and transferring heat produced thereby to a boiler includes providing a fluidized bed of particulate matter and introducing fuel particles thereinto, causing a portion of the fluidized bed constituents to flow upwardly through a heat exchanger which is essentially free of any obstructions to said flow, and reintroducing the portion of fluidized bed constituents which flow through the heat exchanger, back into the fluidized bed. As preferably embodied, the portion of fluidized bed constituents flows into an inlet at the bottom of the heat exchanger from a quiescent zone adjacent the combustion bed and a gas having a combustible component is introduced into the heat exchanger. Advantageously, additional fuel particles are also introduced into the heat exchanger to flow upwardly therethrough.

Abstract: An apparatus and method for supporting and starting up a fluidized bed in which a grate is disposed in a housing for receiving a single bed of particulate material, portions of which are combustible. The interior of the housing below the grate is divided into a plurality of compartments, and an air damper is disposed in each for selectively controlling the flow of air through the compartments and through the respective portions of the grate to selectively fluidize the corresponding portions of the bed of particulate material. A start-up burner is provided for igniting that portion of the combustible portion of the bed of particulate material extending above one of the compartments and additional combustible particulate material is selectively supplied to the portions of the bed.

Abstract: A cleaning plant positioned within an annular fluidized bed combustion chamber is divided into a plurality of separate cleaning stages, wherein a first stage is located adjacent the fluidized bed and additional stages are arranged within the first stage. Each stage comprises a plurality of separate cleaning devices which act in parallel, while cleaning devices of different stages act in series to remove debris from the combustion gases that exit from the fluidized bed combustion chamber.

Abstract: A fluidized bed combustion chamber adaptable for use with relatively large gas turbines and the like, wherein a substantially spherically-shaped outer casing encloses an annular fluidized bed combustion chamber which is mounted on a double bottom air distribution box. A cleaning assembly is positioned within the fluidized bed and the entire combustion chamber is supported on a base plate which extends through the casing and into contact with the box. Compressed air enters the spherical casing, is directed through a pair of cooling gaps, is caused to enter the air distribution box and then passes through the fluidized bed.

Abstract: A method and apparatus for the preparation of coaldust for use with a preheater and a cement calcination apparatus. Exhaust gas from the preheater is mixed with a source of coal and input to a pulverizing mill. The output of the pulverizing mill passes through an air current separator and a cyclone separator. The output of the air-current-separator, a stream of coal gravel, is supplied as a fuel at a calcination point in the calcination apparatus. The exhaust output from the separator provides an input to the cyclone separator which separates coaldust from the gas. The exhaust from the cyclone separator is in part fed-back to a calcination point in the calcination apparatus and is also a part of the stream of gravel. The entire process is closed so that no burnable coaldust is lost to the atmosphere.

Abstract: This invention relates to a process and a reactor for conducting exothermal reactions, for instance combustion, between relatively heavy and relatively light phases in a circulating fluidized bed having vertical cooling surfaces for absorption of the reaction heat resulting from the reaction. The light phase is divided into a primary flow for maintaining a dense conventional part bed and a secondary flow for maintaining a less dense rapid part bed above the dense bed. Said rapid part bed is recycled outside the part beds to the dense part bed for producing the circulating bed. Solid phase is continuously supplied to and withdrawn from the circulating bed, and the secondary flow is supplied to the circulating bed mainly below the cooling surfaces.

Abstract: An electrical discharge is controlled in such a manner as to permit its use to reliably ignite a fuel stream consisting of pulverized coal entrained in air. The ignition technique of the present invention creates expanding and contracting plasma pockets at a rate which is high compared to the velocity of the fuel stream and permits the ignition of the fuel stream in a cold furnace and/or without supplemental combustion of liquid or gaseous hydrocarbon fuels.

Abstract: A fluidized bed reactor preferably for high temperature and pressure operations featuring reactor components and constriction plate arrangements therein capable of essentially unlimited size scaleup, the invention avoiding common reactor design and operational problems usually associated with the high temperature and pressure properties of metallic materials of construction such as: thermal expansion, creep, strength and stress-to-rupture. The present invention includes features for uniformly distributing multiple gaseous, liquid, or solid reactants and fuels into a fludized bed avoiding problems of coking and plugging of distribution pipes and tuyeres due to high temperatures. The present invention is useful for high temperature and pressure combusation, reforming, gasification, reduction, drying and calcination reactions.

Abstract: A method of direct ignition of pulverized coal to furnish energy for warm-up or low load operation of a coal burning furnace comprises forming a fuel stream consisting of a mixture of pulverized coal and air, the fuel stream having an air to coal ratio and/or a flow velocity which fluctuates. The fluctuating fluid stream is introduced into a combustion area where the coal is ignited by an energy source. The fluctuation of the air to coal ratio and/or the fluctuation of the flow speed provide for the air to coal ratio and/or the flow speed to be swept through a range of values which includes the optimum conditions for ignition.

Abstract: A process for oxidizing coal by wet oxidation to produce recoverable heat energy without generating gaseous sulfur-containing by-products. A slurry containing 0.5 or more weight percent coal particles and a stream of oxygen-containing gas are charged to a reaction zone maintained at 475.degree. to 650.degree. F. with pressures of 1400 to 3000 psig.

Abstract: A method and apparatus for operating an industrial furnace system for treng materials is disclosed, characterized in that the heat which is applied to the material to be treated is partially derived from the combustion of a mixture of waste fuel and water such as sewage slurry. Waste heat generated at the outer surface of the furnace and waste heat generated from the cooling of the treated material is further applied to the slurry to partially dry the waste fuel prior to and during the combustion thereof.

Abstract: A fluidized bed heat exchanger in which air is passed through a bed of particulate material containing fuel disposed in a housing. A steam/water natural circulation system is provided and includes a steam drum disposed adjacent the fluidized bed and a series of tubes connected at one end to the steam drum. A portion of the tubes are connected to a water drum and in the path of the air and the gaseous products of combustion exiting from the bed. Another portion of the tubes pass through the bed and extend at an angle to the upper surface of the bed.

Abstract: An apparatus for supporting and starting up a fluidized bed in which a grate is disposed in a housing for receiving a single bed of particulate material, portions of which are combustible. The interior of the housing below the grate is divided into a plurality of compartments, and an air damper is disposed in each for selectively controlling the flow of air through the compartments and through the respective portions of the grate to selectively fluidize the corresponding portions of the bed of particulate material. A start-up burner is provided for igniting that portion of the combustible portion of the bed of particulate material extending above one of the compartments and additional combustible particulate material is selectively supplied to the portions of the bed.

Abstract: A fluidized bed unit in which a grate is disposed in a housing to divide the housing into an upper chamber and a lower chamber. A bed of particulate material including fuel is supported by the grate and extends in the upper chamber. The lower chamber has an inlet for receiving pressurized air for passing through the lower chamber, the grate, and the bed of particulate material to fluidize the particulate material. An electrical heating unit is provided for preheating the air as it passes through the lower chamber to ignite the fuel material during startup.

Abstract: A fluidized bed boiler is equipped with a plurality of slidable sleeves circumscribing the vapor generator tubes disposed therein. By selectively extending or retracting the sleeves over the tubes, the heat transfer characteristics of the tubes exposed to the heat generated within the boiler may be altered. As a consequence, steam output quantity and quality may be easily modulated. In addition, by virtue of the design, tube cleaning may be accomplished with each adjustment pass.

Abstract: A system and method for improving the reaction efficiency of a fluidized bed combustor or reactor in which a combustion supporting gas is passed upwardly through a bed of particulate material to fluidize same and to entrain the relatively fine particulate material in the bed. The entrained material is separated from the gas and is agglomerated externally of the housing before being passed back into the fluidized bed.

Abstract: An individual cell of a fluidized bed includes a static bed disposed immediately below the fluidization region. The static bed contains heavy ores or other suitable dense material that can be heated to a temperature above the ignition temperature of the fuel used in the fluid bed. Should the fluidized-bed temperature fall below the ignition temperature of the fuel, the lower thermal conductivity of the static bed permits it to maintain the ignition temperature and to ignite the fuel until the fluidized bed has been rekindled.

Abstract: A fluidized bed for the burning of pulverized fuel having a specific waterwall arrangement that comprises a structurally reinforced framework of wall tubes. The wall tubes are reversely bent from opposite sides and then bonded together to form tie rods that extend across the bed to support the lateral walls thereof.

Abstract: An ignition, warm-up and low-load-stabilization system for furnaces fired by pulverized coal. In conjunction with a system in which pulverized coal is sent directly from a coal mill to a load-bearing nozzle and in which combustion air is brought to the nozzles from an air preheater that uses hot furnace gases to warm the combustion air, ignitor nozzles are provided that are supplied by pipes bearing coal from which the drying air has been separated. Combustion air for the ignitor nozzles is heated by an independent heat source that heats the combustion air or a portion thereof to a temperature higher than that of the air supplied by the air preheater. Such a coal-fired ignitor burner can replace oil or gas-fired ignitors and warm-up guns and thereby reduce the amount of oil or gas used in ignition, warm-up, and low-load stabilization.

Abstract: The air-supply system for a fluidized-bed furnace includes two air conduits for the same combustion zone. The conduits feed separate sets of holes in a distributor plate through which fluidizing air flows to reach the bed. During normal operation, only one conduit and set of holes is used, but the second conduit and set of holes is employed during start-up.

Abstract: The gas turbine power plant with a fluidized-bed combustor for the burning of coal comprises a closed circuit or loop cooling system for the fluidized-bed combustor through which is circulated liquid metal. The cooling system includes, in the bed of the fluidized-bed combustor, a first heat exchanger by which the liquid metal absorbs heat from the bed and a second heat exchanger by which heated liquid metal is passed in indirect heat exchange with compressed air to heat the latter, the heated compressed air being mixed with the combustion products discharged from the fluidized-bed combustor at a point upstream from the gas turbines.

Abstract: A fluidized bed combustion apparatus comprises a vessel in which a bed of fluidizable combustible and inert materials is supported, an inlet for a flow of fluidizing and combustion gas, an outlet for a flow of heated gas and gas swirling means located in the vessel between the fluidizable bed and the vessel outlet, the function of the gas swirling means being to retain any unburnt or only partially burnt materials in the vessel until combustion is complete.

Abstract: The invention comprehends a burner for powdered fuel comprising an annular conduit for the injection of solid fuel in powder form, included between two coaxial conduits for the injection of air, one internal and the other external in which the three conduits discharge into an expansion and stabilization chamber which is formed by a divergent truncated portion connected to the external air injection conduit and which also has a central cylindrical portion and a terminal convergent truncated portion.

Abstract: A fluidized bed, particulate collector system wherein, in one embodiment, the bed particles have applied thereto at the surface thereof, an additive that serves to adhere particulate, once collected, to the bed particles. The bed particles and/or additive may be combustible or may be incombustible. In one embodiment, the system includes two fluidized beds, in tandem, the first of which collects particulate mostly in the supermicron sizes and the second of which is an electrofluidized bed that collects particulate mostly in the submicron sizes.

Abstract: A fluid heating unit is provided which includes upper and lower drums, a plurality of riser tubes connected between the drum and defining an enclosure, and means defining a cell within the enclosure for maintaining a fluidized bed of particulate material. The heating unit is of the natural circulation type thereby eliminating the need for forced recirculation pumps.

Abstract: A pulverized coal burner for a furnace adapted to be used in conjunction with a pulverizer which reduces coal to approximately 40 microns size in the presence of inert steam which conveys it under pressure to said burner tangentially to spiral the same within a fuel tube around a coaxial central tube axially adjustable within the fuel tube to adjust the relation between flared distribution and mixing members respectively on the discharge ends of said tubes. Combustion air is fed coaxially around the discharge end of the fuel tube for thorough mixture with the coal which is conveyed with a minimum amount of steam through said tube so as not to deter combustion in the combustion zone which is immediately adjacent the discharge end of the fuel and central tubes.

Abstract: The heating power of the fire box of a boiler burning powdered fuel maintained in suspension by fluidizing air is regulated in dependence on the temperature of the burning fluidized fuel layer by means of a heat transmitting system filled with a liquid medium, a first part of the heat transmitting system being embedded in the burning fluidized fuel layer, a second part of such system being disposed in the boiler drum, and a third part of the system being disposed within the fluidizing air supply. The heat transmitting liquid which is heated by its flow through the first part of the heat transmitting system selectively transmits heat to either the second or the third part of the system whereby to regulate the heat output of the boiler.

Abstract: An apparatus is provided for producing a carbon black with a tint residual below -6. The apparatus entail introducing feedstock axially and generating a hot combustion gas vortex in a cylindrical precombustion section of a tubular carbon black reactor, producing a first mixture of feedstock and combustion gases, passing this mixture through an abruptly restricted passage axially connected to the precombustion section, abruptly expanding the first mixture into a frustoconical venturi converging section of the reactor with mixing of this first mixture with an additional flow of combustion gas at the exit of the converging section with the combustion gas entering the converging section in opposite, radial flow thereby forming a second mixture which is admitted into a reaction section of the carbon black reactor.

Abstract: A fluid bed boiler and combustion method are provided having a first fast bed combustion zone followed by a second slow bed combustion zone. Coal, as a typical fuel, and limestone are fed to the first zone, where the coal undergoes combustion and sulfur is captured by the limestone. The solids which flow from the top of the first combustion zone are separated and introduced into a low velocity "slow" bubbling fluid bed in which arrays of heat exchange tubes are immersed. Additional heat transfer to water can be achieved by employing water walls for the first fast bed combustion zone.

Abstract: Nongaseous carbonaceous material is heated by a method comprising introducing tangentially a first stream containing a nongaseous carbonaceous material and carbon monoxide into a reaction zone; simultaneously and separately introducing a second stream containing oxygen into the reaction zone such that the oxygen enters the reaction zone away from the wall thereof and reacts with the first stream thereby producing a gaseous product and heating the nongaseous carbonaceous material; forming an outer spiralling vortex within the reaction zone to cause substantial separation of gases, including the gaseous product, from the nongaseous carbonaceous material; removing a third stream from the reaction zone containing the gaseous product which is substantially free of the nongaseous carbonaceous material before a major portion of the gaseous product can react with the nongaseous carbonaceous material; and removing a fourth stream containing the nongaseous carbonaceous material from the reaction zone.

Abstract: A damper for fluid flow control has a curved extension plate positioned with respect to the circular path defined by the end of a pivotal damper blade to provide close control of the effective open area over a wide range of damper openings. The curved extension plate has a straight portion connected tangentially to one end of an arcuate portion. The arcuate portion of the extension plate approximates the shape of a theoretically ideal curve such that in cooperation with pivoting of the damper blade, the free flow area increases approximately linear with damper opening to provide a linear response between damper blade position and fluid flow rate.

Abstract: A structure is provided for supporting and retaining bed of particulate material, such as a catalyst, in a reactor or the like, so that the material is prevented from falling through the structure when the material is in either a fluidized or agitated condition due to an upward flow of gas through the structure and material or when the material is quiescent. The support and retaining structure also provides a uniformly distributed gas flow through the material supported thereon and includes a first set of elongated, channel-shaped retaining members arranged in parallel, laterally spaced relation with the flanges of the channels extending upwardly and with elongated gaps between the flanges. A second set of elongated, inverted channel-shaped retaining members are also arranged in parallel, laterally spaced relation with their flanges extending downwardly and with elongated gaps between the flanges.

Abstract: In the partial or full combustion of fuels in a fluidized bed, the provision of heat transfer surfaces within the bed impedes particle circulation resulting in localized regions of relative intense chemical reaction which can damage the heat transfer surfaces and cause detrimental physical and/or chemical changes in the bed particles. This problem is exacerbated when the bed is relatively deep and narrow and when the part of full combustion is effected under pressure. In the invention, at least one conduit connects an upper region of the bed to a lower region of the bed, and expedients are provided to cause a downward particle flow through the conduit(s) thereby promoting an upward flow in the bed. Heat exchange surfaces may be in the bed and/or in the conduit(s).

Abstract: A pyrolysis reactor decomposes solid organic waste materials by heating the materials with a fast fluidized particulate source of heat which are admitted to one end of a chamber through first and second inlet pipes. The products of decomposition together with the particulate source of heat are removed through an outlet pipe at the other end of the chamber. The chamber has an intermediate section adjacent the inlet pipes of reduced diameter forming a throat which improves the mixing of the heating particles and the organic waste particles for faster heat transfer.