Abstract: An advanced overfire air system for NO.sub.x control designed for use in a firing system of the type that is particularly suited for use in fossil fuel-fired furnaces and a method of operating such a furnace which embodies an advanced overfire air system. The advanced overfire air system for NO.sub.x control includes multielevations of overfire air compartments consisting of a plurality of close coupled overfire air compartments and a plurality of separated overfire air compartments. The close coupled overfire air compartments are supported at a first elevation in the furnace and the separated overfire air compartments are supported at a second elevation in the furnace so as to be spaced from but aligned with the close coupled overfire air compartments.

Abstract: A continuous fluidized-bed combustion process for particulate carbonaceous feedstock of high ash content. The feedstock fuel is prepared from culm or mine tailings washed in a dense media and crushed to yield a fuel product having an ash content in a range of about 30 percent to about 50 percent, by weight. The feedstock fuel is mixed with fine particles of scavenging material, such as limestone or dolomite, and the resulting feedstock mixture is burned in a circulating fluidized-bed combustion chamber. A portion of the ash remaining after combustion is discharged out the bottom chamber, the remainder being carried with the combustion gases through a hot cyclone and heat exchangers for generating power. The ash within these gases is separated and recirculated through the fluidized bed, and the combustion gases are discharged.

Abstract: A process and device for introducing additives, in particular energy carriers, into a cupola or shaft furnace. The additive is carried with combustion air stream and introduced therewith in the furnace shaft, a depression being created at the point where the additive is fed into the combustion air stream, so that the additive is fed into the combustion air stream, so that the additive is aspirated by the combustion air into the combustion area of the furnace shaft.

Abstract: A method and apparatus starts the boiler of a solid-fuel fired power plant and ensures the burning process of the fuel. The main fuel of the boiler is ignited by entering an auxiliary fuel stream gasified and ignited with a plasma torch (1). Efficient mixing and safe ignition of the main fuel with the auxiliary fuel is ensured by a turbulent feed of the auxiliary fuel and a nozzle (12) through which the auxiliary fuel is entered into the main fuel stream.

Abstract: A boiler furnace combustion system typically includes main burners disposed on side walls of or at corners of a square-barrel-shaped boiler furnace having a vertical axis, the burner axes being directed tangentially to an imaginary cylindrical surface coaxial to the furnace. Air nozzles are disposed in the boiler furnace at a level above the main burners, so that unburnt fuel left in a reducing atmosphere or a lower oxygen concentration atmosphere of a main burner combustion region can be perfectly burnt by additional air blown through the air nozzles. The present invention provides two groups of air nozzles disposed at higher and lower levels, respectively. The air nozzles at the lower level are provided at the corners of the boiler furnace with their axes directed tangentially to a second imaginary coaxial cylindrical surface having a larger diameter than the first imaginary coaxial cylindrical surface.

Abstract: A method and apparatus are provided for reacting waste matter in a flame using fuel such as a flammable gas and oxygen. The apparatus includes a substantially cylindrical burner comprising a burner base and a removably attachable base extension having a diameter greater than that of the base. The base and the base extension each have aligned central nozzles extending their entire lengths for ejecting waste matter to be reacted, and aligned fuel nozzles radially spaced from each of the central nozzles for ejecting fuel to be ignited. The perimeter of the burner base extension is notched to provide channel-shaped peripheral oxygen nozzles. A substantially cylindrical cooling jacket surrounding the burner is adapted to receive oxygen which passes through the space defined by the outer surface of the burner base and the inner surface of the cooling jacket, then through the peripheral oxygen nozzles of the base extension.

Abstract: A burner for the combustion of fine-grained to dusty solid fuels incorporates a central internal tube for supplying the solid fuels and an annular gap surrounding the internal tube and delimited by a cooled external tube, for supplying oxygen or oxygen-containing gas. The annular gap ends externally by an exhaust port directed obliquely relative to the longitudinal axis of the burner and peripherally surrounding the end of the central internal tube, or by a plurality of exhaust ports annularly disposed about the longitudinal axis of the burner. In order to ensure the complete combustion of the fine-grained to dusty fuels at a long service life of the burner, the inclination of the exhaust port(s) relative to the longitudinal axis of the burner is below 20.degree.. The exhaust port(s) is/are arranged transverse to the longitudinal axis of the burner and in the radial direction relative to the same at a distance of between 5 and 30 mm from the inner wall of the internal tube.

Abstract: A pulverized coal fuel injector contains an acceleration section to improve the uniformity of a coal-air mixture to be burned. An integral splitter is provided which divides the coal-air mixture into a number separate streams or jets, and a center body directs the streams at a controlled angle into the primary zone of a burner. The injector provides for flame shaping and the control of NO/NO.sub.2 formation.

Abstract: A cyclone burner is provided which comprises an outer barrel with first and second ends and an inlet conduit extending tangentially into a side of the barrel for receiving a mixture of fuel and air. A hollow frustocone extends from one of the barrel ends and an injection nozzle extends from the frustum of the frustocone for discharging the mixture into a combustion chamber. A primary air vent extends axially into the other end of the barrel for venting a portion of the mixture. An outer sleeve is connected to a rod which extends through the outer barrel, into the primary air vent, and projects therefrom for actuation of the outer sleeve into the injection nozzle for controlling the amount of discharge of the mixture through the injection nozzle. An inner sleeve retractable into the outer sleeve is connected to a tube in which the inner rod extends.

Abstract: A burner apparatus for pulverized coal comprises a pulverized coal supply pipe, a starter oil burner extending within the pulverized coal supply pipe to define therebetween a tubular passage through which a mixture of combustion air and pulverized coal passes into a furnace, a flame holder provided at an outer periphery of one end of the pulverizerd coal supply pipe facing to the furnace, a cylindrical member disposed in the tubular passage for dividing a part thereof into two coaxial passage parts, and a valve adapted to close an axial end opening of the cylindrical member for varying a concentration of pulverized coal in a radial outer passage part of the coaxial passage parts.

Abstract: A combustion process for nitrogen- or for sulphur- and nitrogen-bearing fuels wherein fuel combustion is divided, by staged oxygen (preferably in the form of air) injection, into at least two combustion zones. The first combustion zone involves providing fuel-rich stoichiometric conditions under which nitrogen chemically bound in the fuel (i.e. fuel-bound nitrogen) is substantially converted to molecular nitrogen. The second (final) combustion zone comprises at least two stages. In the first stage of the final combustion zone, combustion products from the first combustion zone are further conbusted under a condition of fuel-rich stoichiometry, preferably at an oxygen/fuel stoichiometric ratio of from about 0.08 to about 1.0 and at a temperature of less than about 2200 K. In the second stage of the final combustion zone, combustion products from the first stage are combusted at an oxygen/fuel stoichiometric ratio of greater than about 1.0 and at a temperature of less than about 1500 K.

Abstract: A reactor in which a furnace and a heat recovery area are provided. A bed of solid particulate material including fuel is supported in the furnace and air is introduced into the bed at a velocity sufficient to fluidize same and support the combustion or gasification of the fuel. The products of combustion (or flue gases) pass upwardly through the furnace and transfer heat energy to the walls thereof to produce steam. Flue gases leaving the upper region of the furnace section are transported to a heat recovery area, which functions to remove additional heat energy from the flue gases for producing the steam. A flue gas by-pass system is provided which transports relatively hot flue gases from a lower region of the furnace section to the heat recovery area for improving isothermal operating conditions and optimizing reactor performance. One or more conduits pass flue gases directly from selected extraction points within the lower region of the furnace to an upper portion of the heat recovery area.

Abstract: A hybrid combustion system is provided combining advantages of a fluidized bed combustion portion and a pulverized coal combustion portion. The former portion includes a fluidized bed chamber, a coal mill without an air separator, a recycling duct connected to the coal mill, a coal supply duct, and a spray feeder. The fluidized coal combustion portion includes a pulverizing coal mill with air separator, a blowing duct for blowing ground coal, at least one pulverized coal burner and an air recycling duct for recycling combustion air. Fluidized bed combustion takes place in a lower part of the system and pulverized coal combustion takes place above the fluidized bed combustion. Each of the portions may be independently operated of the other. A main combustion chamber is common to both the fluidized bed portion and the pulverized coal portion. A related process is also described.

Abstract: The present invention relates to a pulverized coal ignition burner apparatus for use with a pulverized coal boiler or the like for a thermal power plant. The apparatus is so constructed that the pulverized coal is directly burned without generation of a large amount of NOx and without using auxiliary fuel such as light oil, heavy oil and gas that are needed in the conventional apparatus. In the pulverized coal burner apparatus, an ignition region (39) in which a density of the pulverized coal of the mixture of the air and the pulverized coal supplied from a pulverized coal supply source (18) to a pulverized coal burner (4 to 9) by means of a delivery system (23, 50) is enhanced and the flow rate of the mixture flow is low is formed within the pulverized coal burner. The pulverized coal within this region is ignited by an igniter (41).

Abstract: A system and method for controlling the sealing efficiency and recycle rate in a fluidized bed reactor in which air is introduced into two chambers found in a sealing vessel for receiving the separated solids from the separator. The air is introduced into two chambers in the sealing vessel in a direction opposite to that of the flow of the separated solids through the vessel. One of the chambers is located below the separator dipleg and in alignment therewith and the other chamber surrounds the first chambers. The air flow through each path can be separately adjusted as necessary.

Abstract: In a power plant boiler having oil and coal burning capability, a coal disperser support tube and an oil gun extending through the disperser support tube are slidable in a bearing sleeve extending through a removable access plate in the wall of an elbow of a coal guide. The disperser is arranged to be withdrawn into the coal guide delivery pipe by a first two-position, reversible, linear pneumatic actuator, and the oil gun is arranged to be withdrawn into the disperser support tube by a second similar actuator the body of which is carried with the piston of the first actuator and the piston of which is connected to the oil gun. The piston of the second actuator is withdrawn when the piston of the first actuator is extended to minimize space requirements. The dispenser support, oil gun, actuators, and associated parts are all mounted on the removable access plate, and can be removed as a unit with the access plate.

Abstract: A combustion device for the pyrolytic destruction and gasification of industrial or other wastes, or lower sulfur fuels, is provided which includes an elongated cylindrical kiln body. Air is introduced into the kiln body by a plurality of pipes which define different combustion zones therewithin. A sorbent such as pulverized limestone may be introduced into each zone for reaction with the feedstock material to reduce undesirable flue emissions. The pipes are oriented within the kiln body to sweep the feedstock along the kiln body in a generally cyclonic pattern of torroidal shape and cross-sectional contour. The kiln may be rotated at various speeds corresponding to the force of the introduced combustion air to fluidize and entrain the feedstock material to be combusted.

Abstract: A pulverized fuel distribution cone for use in a pulverized fuel burner having a tubular burner pipe with flanged and furnace ends and an elbow connector having a flanged end for connection of the elbow to the flanged end of the burner pipe. The distribution cone includes an open base section and an open outlet end portion extending into the burner pipe. A planar flange extending outwardly from the base section of the cone is retained between the flanged ends of the elbow connector and pipe. The flow cone preferably is positioned in the pipe at a distance from the furnace end of the burner of at least four times a diameter of the pipe. An angle between the wall of the cone and its base in the range of from 75.degree. to 85.degree. results in a flow deflection of between 5 and 15 degrees, respectively. The length of the cone in the flow path preferably is in a range from four to fourteen inches.

Abstract: A pulverized fuel and air mixture is burnt in conditions giving relatively low NO.sub.x emissions by using a burner which has concentric passages for a primary air-fuel mixture and secondary and ternary air flows respectively. In the passage for the primary air-fuel mixture guide elements are provided at angularly spaced positions. The elements are arranged to deflect the flow in the passage and so produce regions of high fuel concentration. Downstream of the guide elements and adjacent the outlet of the passage flow disturbing members are provided in angularly spaced positions to modify the flow pattern of the air-fuel mixture at the passage outlet. The members assist stabilization of the flame front at the burner outlet and complement the action of the guide elements in promoting combustion conditions that lead to low NO.sub.x emissions.

Abstract: There is disclosed an oxygen heater, which uses a part of supplied oxygen as auxiliary combustion oxygen, a hot oxygen lance and a pulverized solid fuel burner, both having oxygen heaters. The oxygen heater (1) has a combustion chamber (4) for both mixing and burning fuel with the part of the supplied oxygen. An oxygen-jetting opening (8) is disposed around the combustion chamber. The oxygen jetted out of the opening forms a gas curtain between an internal wall (2) and a flame (10) produced in the combustion chamber, and is heated by the flame. Both the oxygen lance and the burner includes the above-mentioned oxygen heater.

Abstract: In this combustion process a fluid fuel such as pulverized coal mixed with primary air is injected along an axis and secondary air is injected along a helical path around the axis. Tertiary air is injected around the combustible fluid and the secondary air in substantially the same direction as the combustible fluid, in a substantially circumferentially continuous coaxial ring which is laterally confined downstream of the injection point.

Abstract: The invention concerns a fluidized bed process for the gasification and combustion of fuels in differently fluidized zones separate from one another, the fuel being charged into a drying and pyrolysis zone with lower fluidization and solids transport downwards, the solids conveyed downwards being conveyed from the lower part of the drying and pyrolysis zone to the lower part of a combustion zone with higher fluidization and solids transport upwards and recirculating, after passing the combustion zone, from the upper zone thereof to the drying and pyrolysis zone, comprising that the solids are conveyed upwards in a combustion zone operated as a fast or turbulent fluidized bed beyond the bed height in the drying and pyrolysis zone and are subsequently forcibly deflected so that the solids drop down on the surface of the bed in the drying and pyrolysis zone as a shower of particles, that the fuel is metered into the shower of particles and that the gases emerging from the combustion zone are passed under use of

Abstract: An oxygen-fuel burner has a pipe 20 for fuel, for example pulverized coal carried in air, and two pipes 22 and 24 for oxygen. The burner is typically mounted horizontally above a burden to be heated. The oxygen pipes 22 and 24 have separate outlets disposed such that the flame is caused to curve towards the burden. The relative rates of supply of oxygen to the two passages are varied so that the flame is moved across at least part of the burden.

Abstract: The wall (5) of a tube (2) for delivering pulverized fuel to the outlet (4) of an oxy-fuel burner (1) forms part of a chamber (6) which is pressurized or evacuated. The pressure in the chamber is continuously monitored. If the pressure in the chamber (6) changes in a way indicative that the wall (5) of the oxy-fuel burner (1) has failed the oxy-fuel burner (1) is automatically shut down.

Abstract: A burner assembly (10) for the combustion of pulverized coal in furnaces (12) and the like. The assembly comprises wind box means (23) for providing a primary source of air to the interior (13) of the furnace; feeding means (30) for delivering pulverized coal through a wall (11) of the furnace and into the interior thereof; means for supplying (31) a secondary flow of air through the feeding means and into the furnace separate from the primary flow of air; and swirler means (32) having a plurality of blades around the feeding means so that the first flow moves around and through the blades for imparting a rotation to the primary flow of air to penetrate the pulverized coal funnel. A method for supplying pulverized coal to furnaces and the like through burner assemblies is also provided and results in increased combustion efficiency.

Abstract: The invention relates to a PFBC power plant comprising a bed vessel (12) which is divided into a first section (14) and a second section (16) by a vertical partition (17) which reaches up to the upper wall of the bed vessel (12) so that freeboards (86 and 46, respectively), which are separated from each other, are formed. The first section (14) of the bed vessel (12) forms a gas generator in which a burnable gas is generated. This burnable gas is cleaned in a gas cleaner (90) and is burnt in a secondary combustion chamber (98) and is mixed with the combustion gases from the second section (16) of the bed vessel (12) and raises the temperature of the gas supplied to a gas turbine to an optimum level for the gas turbine.

Abstract: Disclosed is a burner for the partial combustion of a solid carbonaceous fuel wherein coal, e.g., finely divided coal, is supplied to a reactor space via a central channel disposed along the longitudinal axis of the burner, and oxygen-containing gas is supplied via an annular channel surrounding said central channel, and heat from the combustion is removed from the hollow front face of the burner by coolant flowed through said front face spirally about the longitudinal axis of the burner.

Abstract: A tuyere for a blast furnace comprises water-cooled tuyere; and a burner removably mounted inside the water-cooled tuyere to burning pulverize coal. The burner comprises an inner pipe, an intermediate pipe and an outer pipe which are concentrically arranged. The inside of the inner pipe is used for a pulverized coal path, an oxygen feed path being in between the inner pipe and the intermediate pipe and a flame temperature control gas feed path in between the intermediate pipe and the outer pipe. The burner is equipped with a water-cooled jacket outside of the top end of the burner.

Abstract: A pulverized coal combustion apparatus comprises a burner through which pulverized coal and carrier air are passed to be burnt in a combustion chamber, and a flame retainer disposed at an end of the burner. The flame retainer includes a flared tube and an annular plate, which plate has a plurality of radially inwardly projecting parts equiangularly spaced from each other. The annular plate comprises a plurality of ceramic pieces and a plurality of fastener elements, both of which are arranged and assembled alternately to form the annular plate. Each ceramic piece is so shaped that it projects radially inwardly to serve as the projecting part when assembled. The ceramic piece has at opposite sides thereof smoothly curved edge surfaces, and the fastener element has at opposite sides thereof smoothly curved edge surfaces which are engaged with the curved edge surfaces of neighboring two ceramic pieces.

Abstract: Enhanced combustion of pulverized fuel in an oxy-fuel burner (10) is achieved by replacing the conventional pulverized fuel feed with a dense phase material flow transport system. This enables materials which would hitherto have been discarded as waste to be used as a viable energy source. In addition to greatly enhancing combustion the swirlers conventionally associated with the oxy-fuel burner (10) may be omitted.

Abstract: Disclosed is a burner for the partial combustion of a solid carbonaceous fuel wherein coal, e.g., finely divided coal, is supplied to a reactor space via a central channel disposed along the longitudinal axis of the burner, and oxygen-containing gas is supplied via two annular channels surrounding said central channel, and heat from the combustion is removed from the hollow front face of the burner by coolant flowed through said front face spirally about the longitudinal axis of the burner.

Abstract: A burner which is suitable for use in combusting pulverized coal and which can be used as an igniter for igniting the main burners in steam raising plant. The burner has an electrically powered torch which generates a continuous plasma which extends into a devolatilization zone of the burner, and primary conduits are provided for directing a primary supply of dense phase pulverized coal into the devolatilization zone. The burner is constructed also to include a combustion zone which surrounds the devolatilization zone. The burner is constructed also to include a comubstion zone which surrounds the devolatilization zone, and secondary conduits are provided for directing a secondary supply of pulverized coal into the combustion zone along with a supply of combustion supporting air.

Abstract: A power plant for burning a fuel at a pressure exceeding atmospheric pressure, in particular a PFBC power plant with a bed vessel enclosed in a pressure vessel, includes a plurality of valves in a hot gas pipe between the bed vessel and a turbine, and an air duct between a compressor and the bed vessel, and in a short-circuit connection between the ducts which are constructed as a single valve unit located in a valve housing. Arranged centrally in the valve housing is a cylinder providing passage for gas to the turbine and an annular channel is formed between the valve housing and the cylinder for compressed air from the compressor. At least one valve is provided in the cylinder and the channel includes a plurality of valves arranged in parallel. Between the annular channel and the cylinder a short circuit connection is provided having a plurality of valves. The valves in the air duct and the valves in the short circuit connection have valve discs arranged on a common spindle.

Abstract: Disclosed is a burner for the partial combustion of a solid carbonaceous fuel, and suitable for use in an reactor having a plurality of burners wherein e.g. finely divided coal is supplied to a reactor space via a central channel disposed along the longitudinal axis of the burner, and oxygen-containing gas is supplied via an annular channel surrounding said central channel and configured for said gas to intersect said coal at an acute angle, and heat from the combustion is removed from a dimensioned curvilinear hollow front of the burner by coolant flowed radially at constant momentum through said hollow front.

Abstract: A waste fuel incineration process and system operates at very high temperatures with excess under fire air for high efficiency combustion of waste as a fuel and for decomposition of any toxic waste. The system is applicable for clean burning volume reduction of waste and for power generation and co-generation of heat. The control elements are constructed and arranged and the control circuit programmed for maintaining the primary combustion temperature at a target temperature selected in the range of approximately 1600.degree.-1800.degree. F. (871.degree.-982.degree. C.

Abstract: A power plant utilizing combustion of fuel in a fluidized bed contains a particulate sulfur-absorbing material. A discharge device for bed material and ashes includes a crusher which breaks down the material so that it can be transported away or so that unconsumed absorbent in the bed material is exposed for reuse in the bed. The crusher has a stationary grinding portion and a rotating grinding portion receiving bed material. Scrapers selectively scrape off layers of material during rotation of the rotating grinding portion thus distributing the material around the periphery of the grinding portions.

Abstract: A fluidized bed combustor for burning solid fuel or dirty liquid fuels comprised of a bubbling fluid bed with tubes in the bed, an isothermal, non-heat extractive freeboard/recycle cyclone flow path, a hot recycle cyclone, a connective heat exchanger and a particle filter. The bubbling fluid bed is operated at low superficial velocities of 0.5 to 7 ft/sec and is composed of fine particulates 45 to 2000 microns in diameter with up to 40% less than 200 microns. Fines elutriated from the bed are isothermally recycled back to the bed resulting in high combustion efficiency and good sulfur oxide suppression from sorbents contained in the bed. The material recycled in one hour is equivalent to twice the weight of the bed. Ammonia injected upstream of the recycle cyclone suppresses nitrogen oxides with high efficiency because of the excellent mixing in the cyclone. The heat transfer coefficient on the tubes in the bed is increased at least 2 to 4 times because of the fine particulate in the bed.

Abstract: In this combustion process a fluid fuel such as pulverized coal mixed with primary air is injected along an axis and secondary air is injected along a helical path around the axis. Tertiary air is injected around the combustible fluid and the secondary air in substantially the same direction as the combustible fluid, in a substantial circumferentially continuous coaxial ring which is laterally confined downstream of the injection point.

Abstract: An improved burner for the combustion of coal, oil or gas places a plurality of retractable and rotatable gas elements in close proximity to the outlet end of a tubular burner nozzle of the burner which are shielded from combustion air provided around the tubular burner nozzle by a flame stabilizing ring having a plurality of openings adapted to closely receive each of the plurality of retractable and rotatable gas elements. Eddies produced by the flame stabilizing ring create a low oxygen/fuel rich flame resulting in reduced NO.sub.x formation.

Abstract: In order to be able to handle multiple fuels in a bubbling-bed fluidized bed combustor, a number of elements are combined together and a number of systems are described which utilize these elements in order to be able to appropriately process different types of fuels. With respect to the handling of multiple fuels by a bubbling-bed fluidized bed combustor which need not be reconfigured for each type of fuel, the combustor in the subject invention is provided with a closely-coupled pyrolyzer or gasifier. The close-coupled pyrolyzer not only permits the processing of virtually any type of fuel into two fuel streams which are immediately usable by the combustor but also has certain advantages in terms of reducing environmental pollutants. The above-mentioned close-coupled pyrolyzer also results in improved performance aside from the pollution aspects mentioned above.

Abstract: Solids are separated from the flue gases of a fluidized bed reactor with a circulating bed and provided with cooling surfaces and are recycled to the reactor through return ducts disposed at different heights in the reactor. To control the operation of the reactor the heat removed from the reactor chamber is regulated by changing the suspension density in the reactor chamber. A required suspension density is obtained by regulating the flow of the solids through each return duct.

Abstract: An apparatus for the combustion of a poorly combustible fuel in a fluidized bed comprises a vertical front wall through which the poorly combustible fuel is delivered in particulate form and two lateral walls extending rearwardly from the front wall. A fixed grate extends from a front input end towards a rear discharge end between the lateral walls, and the two sides and the front input end of the grate define spaces with the lateral walls and the front wall, respectively. The fixed grate is upwardly inclined over at least a portion of its length from the input end to the discharge end whereby the discharge end is disposed above the input end, and the particulate fuel is delivered to the input end for forming a fluidized bed on the grate.

Abstract: A fluidized bed reactor and method of operating same, in which a gas column is formed above a fluidized bed which contains a mixture of air, the gaseous products of combustion from a fluidized bed, and particulate material entrained by the air and the gaseous products of combustion. The gas column is saturated with the particulate material of the particulate material is separated from the mixture. A portion of the separated particulate material is injected back into the bed, and the remaining portion is passed to external equipment.

Abstract: A method for starting up a partial combustion process, using a burner, wherein finely divided carbon-containing fuel is supplied to a reactor or gasifier and an oxygen-containing gas is supplied separately from the said fuel to the reactor or gasifier and is mixed with the said fuel adjacent the outlet of the burner in the reactor or gasifier. During a predetermined period a low rank particulate carbon-containing fuel is supplied to the reactor prior to the start of the partial combustion process, said low rank fuel spontaneously reacting with oxygen when brought into contact with the said oxygen-containing gas and subsequently switching the burner to a less reactive finedly divided carbon-containing fuel.

Abstract: A combustion apparatus for low concentration NOx for burning gas, oil and coal along the same axis, having overcome the drawbacks of the prior art, without hindering the whirling of the air and also having prevented clogging of the nozzle and combustion vibration is provided, which apparatus is provided with a means for carrying pulverized coal by a primary air, a means for feeding a gas fuel through a gas nozzle, a means for separating combustion air into a secondary air and a tertiary air and feeding these airs, and a means for feeding and spraying an oil, and which apparatus is characterized by providing an annular space part between the flow paths of the secondary air and the tertiary air; and also arranging the gas nozzle penetrating through the annular space part in a movable manner in the axial direction.

Abstract: A fluidized bed boiler is controlled such that, when the fuel supply quantity thereof is changed from F.sub.0 to F.sub.1, the fuel supply quantity is changed to a level greater than the difference between F.sub.1 and F.sub.0, the fuel supply quantity is changed to a level smaller than the difference between F.sub.1 and F.sub.0, and the fuel supply quantity is then set to F.sub.1.

Abstract: A combustion plant includes a circulating fluid bed, which is maintained by the supply of fuel, inert material and oxygen-containing fluidizing gas to a vertical furnace shaft. This is, at its upper end provided with an outlet for combustion gases and bed materials, which is separated from gas in a separating means, and by way of a lock is returned to the furnace shaft. The separating means is of a mechanical type, and located vertically above a further vertical shaft communicating with the lock. The further shaft encloses distribution means for the particles and a heat exchanger for cooling the particles falling from the gas stream, before they are re-introduced into the furnace shaft by way of the lock.

Abstract: A device for dispersing fine particles in the agglomerated state comprises a body, a fine particle channel provided in the body and terminating in a spout in the form of a slit, and a clearance provided in the body, inclined downstream with respect to the fine particle channel and communicating with the fine particle channel for emitting a gas into the fine particle channel. Since the spout is in the form of a slit, a large amount can be simultaneously dispersed without losing the dispersing performance of the single hole type dispersing device. When a plurality of such dispersing devices are attached to the combustion gas passage forming wall of a furnace and arranged so that the more upstream they are disposed, the greater is the throw of the reactant-containing gas emitted therefrom, the reactant is diffused in the combustion gas and uniformly distributed.

Abstract: A steam generator and a method of burning fuels therein. A combustion chamber of gas-tight pipe walls has a fluidized bed. Above the bed is a free space with an incrementally lower solids density that accommodates heat-convection surfaces. Coarse-particle precipitators communicate with the top of the combustion chamber with their solids-extraction outlet communicating with the fluidized bed through a feedback system. The combustion chamber, its heat-convection surfaces, the coarse-particle precipitators, and the feedback system are surrounded by pressurized vessel. The fuel is burned in the fluidized bed under pressure. Densities of 0.5 to 5 kg of solids per kg of flue gas are maintained in the free space (4) above the bed by means of fluidizing rates of 1 to 5 m/sec. The temperature of and load on the fluidized bed are regulated by the amount of solids returned to the bed.

Abstract: Fluidized bed reactor and a process for the operation of a circulating, fluidized bed reactor, by which a solid particle material, in particular carbonaceous fuel, is introduced into the lower part of the reactor and is formed to a fast bed by a fluidization gas containing a gaseous reactant material, in particular oxygen, introduced into the reactor bottom, while non-reacted particles are removed from the reactor top and recirculated to the bed. By removing a predetermined fraction of the solid particle material in the reactor from at least one site positioned below the reactor top, subjecting it to thermal treatment and recirculating it to at least one other, lower positioned site of the bed, enhanced possibilities for process optimalization are achieved.