Abstract: A fluidized bed reactor including in its lower part a furnace section having a bed of fluidized solid particles, the furnace section being delimited by side walls such as external side walls and/or partition walls and a bottom grid, and a supplying device for introducing gas into the furnace section at a level above the bottom grid, the supplying device including a gas source chamber, an opening in at least one of the side walls at a level above the bottom grid, and a conduit having a first end connected to the opening and a second end connected to the gas source chamber. The conduit includes a solid flow seal preventing solid particles from flowing backwards from the furnace section into the conduit in a manner preventing or noticeably decreasing introduction of gas from the gas source chamber to the furnace section.

Abstract: A boiler comprising a circulating fluidized bed hearth, a separator member for separating flue gas and solids extracted from the hearth, an external dense fluidized bed between the solids outlet of the separator member and the base of the hearth, the external bed containing a first heat exchanger in which a coolant fluid to be evaporated circulates. The outlet of the first heat exchanger is connected to a second heat exchanger placed in the hearth.

Abstract: A power plant which combusts fossil fuel and biomaterial or waste includes a large boiler plant having at least one device for the combustion of fossil fuel. At least one additional combustion device is connected to the large boiler plant via at least one connection channel. The additional combustion device includes a grate hearth for the combustion of biomaterial or waste. The additional combustion device includes at least one heat exchanger device which is integrated into the water/steam circuit of the large boiler plant.

Abstract: An apparatus for recycling municipal waste as energy includes a shredder for shredding the waste, and removing rejects, the rejects from the shredder being sorted into a first stream of inert matter that is substantially unpolluted with organic matter and into a second stream of inert matter that is substantially polluted with either organic matter or with combustible heavy elements; a first outlet for removing the second stream of inert matter; a circulating fluidized bed reactor for receiving the shredded waste and producing gases with solid particles therein; a cyclone for separating out the solid particles and receiving the gases output by the reactor; a recuperator boiler into which the gases output by the cyclone are discharged and which is provided with a first set of heat exchangers, the boiler including a dust-filtering hopper; a second outlet for removing the solid particles from the dust-filtering hopper; a second set of heat exchangers disposed in a chamber into which the gases are fed after trans

Abstract: In an improved system for recovering heat from a combustion gas produced by burning wastes, the combustion gas or combustible gas produced by partial burning of the wastes subjected to dust filtration in a temperature range of 450-650.degree. C. at a filtration velocity of 1-5 cm/sec under a pressure of from -5 kPa (gage) to 5 MPa before heat recovery is effected. The dust filtration is preferably performed using a filter medium which may or may not support a denitration catalyst. Heat recovery is preferably effected using a steam superheater. The dust-free gas may partly or wholly be reburnt with or without an auxiliary fuel to a sufficiently high temperature to permit heat recovery. The combustion furnace may be a gasifying furnace which, in turn, may be combined with a melting furnace.

Abstract: The invention relates to a steam generator, which consists of a combustion chamber (1), a radiation part (2) and a convection part (3) and which has at least two vertical gas passes (4, 5) following the combustion chamber (1), in each case with a 180.degree. deflection of the flue gas (12), the combustion chamber (1) and the gas pass (4) being separated from one another by means of a first partition (14) and the two gas passes (4, 5) being separated from one another by means of a second partition (6). It is defined in that the second partition (6) is designed, at its lower end, in such a way that the passage area for the flue gas (12) from the vertical pass (4) with downward flow to the vertical pass (5) with upward flow has a variable value over the width, the passage area being smaller in the middle than on the outside. The secondary flow occurring during deflection is thereby reinforced, in the wall region the vortices of said secondary flow rotating opposite to the direction of the main flow deflection.

Abstract: A fluidized-bed thermal reaction apparatus burns or gasifies combustible matter containing incombustible components, so that deposition of incombustible components in a fluidized-bed furnace is prevented, and incombustible components are smoothly removed, thereby efficiently burning or gasifying the combustible matter. A weak diffusion plate, a strong diffusion plate, and an auxiliary diffusion plate, each have a large number of fluidizing gas feed holes. An incombustible component outlet is disposed between the auxiliary diffusion plate and the strong diffusion plate. A part of fluidizing gas is supplied from the incombustible component outlet, or the incombustible component outlet is provided to open horizontally. Thus, a continuous fluidized bed circulating stream is formed in the furnace bottom. The weak and auxiliary diffusion plates each has a downwardly inclined surface extending toward the incombustible component outlet.

Abstract: A dense fluidized bed exchanger includes a casing the vertical longitudinal walls of which consist of tubes conveying a heat-conducting fluid, the casing being divided lengthwise into chambers separated from each other by a baffle consisting of a wall consisting of tubes conveying a heat-conducting fluid. The vertical longitudinal walls consist of horizontal tubes and the baffle extends from the bottom wall of the casing to a height less than that of the latter and consists of superposed hairpin-shape transverse extensions of tubes of each of the vertical longitudinal walls disposed perpendicular to the tubes and extending to the opposite vertical longitudinal wall.

Abstract: A fluidized bed combustion system is disclosed and in particular a fluidized bed combustion system particularly well suited for the combustion of oil shale, generating steam thereby. The fluidized bed combustion system includes a furnace volume having a multi-chambered upper segment thereof, a deentrainment zone, a fluidized bed having a plurality of isolatable segments thereof, a fluidized bed ash cooler having a plurality of isolatable segments thereof wherein the fluidized bed ash cooler is in fluid communication with the furnace volume, a fuel supply means in fluid communication with the furnace volume for delivering oil shale thereto for combustion therein, a backpass volume defined by a plurality of backpass wall tubes integral to a thermodynamic steam cycle and in fluid flow relation with the furnace volume and a plurality of circulatory fluid flow paths integral to a thermodynamic steam cycle and operative to conduct the flow of steam or water therethrough.

Abstract: A process and apparatus for drying material, in which a previous dried material is mixed into the wet material to be dried to produce a dried mixture of different particle sizes. The process for drying material requires less industrial equipment implemented in a more economical and simpler plant that can be operated with low energy and maintenance requirments. The amount of fine material obtained after drying is measured and the amount of fine previously dried material mixed into the wet material to be dried is then set in inverse proportion to the quantity of fine dried material produce.

Abstract: In a fluidized-bed thermal reaction apparatus for burning or gasifying combustible matter containing incombustible components, deposition of incombustible components in a fluidized-bed furnace is prevented, and incombustible components are smoothly removed, thereby efficiently burning or gasifying combustible matter. The fluidized-bed thermal reaction apparatus has a weak diffusion plate, a strong diffusion plate, and an auxiliary diffusion plate, each having a large number of fluidizing gas feed holes, and an incombustible component outlet disposed between the auxiliary diffusion plate and the strong diffusion plate. A part of fluidizing gas is supplied from the incombustible component outlet, or the incombustible component outlet is provided to open horizontally. Thus, a continuous fluidized bed circulating stream is formed in the furnace bottom. The weak and auxiliary diffusion plates each has a downwardly inclined surface extending toward the incombustible component outlet.

Abstract: Apparatus for cooling ash exiting from circulating fluidized bed equipment includes an enclosure having a floor, a plurality of walls disposed around the floor and a ceiling. The enclosure also has an inlet and an outlet. The outlet is disposed in one of the walls near to the floor and the apparatus also includes tubing disposed within the enclosure for heat exchange relationship with ash entering the inlet of the ash cooler. In some forms of the invention the floor is planar and is disposed in oblique relationship to a horizontal plane. The outlet may be disposed proximate to the floor at the lowest elevational part thereof. The enclosure may be generally rectangular and may have first and second opposed sides and opposed third and fourth sides. The first and second sides are longer than the third and fourth sides. In some cases the ratio of the length of each of the first and second sides to the length of the third and fourth sides is two or three to one.

Abstract: A fluidized bed reactor includes an axial recirculating fluidized bed and at least first and second lateral dense fluidized beds, respectively disposed along a first and a second wall of the jacket of the reactor. Waste is fed via at least one point on the first wall of the jacket of the reactor, above the first lateral dense fluidized bed. The reactor includes at least one duct for extracting non-fluidizable heavy elements at the base of the first lateral dense fluidized bed.

Abstract: A shield in the form of a "cast refrac" (S.U.B.S.) for a diffuser port in a circulating fluidized bed to deflect eroding particulates away from the port. The S.U.B.S. includes an upper portion with a tear-drop shape, a lower portion, and side intermediate portions to surround the port, and an attached insert to be received by or around the port.

Abstract: A non-mechanical leak proof coupling for use on a gas carrying pipe having two pipe sections which are moveable relative to each other. The coupling includes a first pipe section having an upstream end in flow communication with a stationary gas source and further includes a second pipe section having a downstream end in flow communication with a vibrating distribution chamber. A downstream end of the first pipe section and an upstream end of the second pipe section are disposed in closely spaced relation to define a gap therebetween. The first pipe section downstream end is in flow communication with the second pipe section upstream end such that the pressurized gas is communicated between the first pipe section to the second pipe section for discharge to the vibrating distribution chamber.

Abstract: A method and apparatus for treating wastes by gasification recovers useful resources including energy, valuables such as metals, and gases for use as synthesis gas for chemical industries or fuel. The wastes are gasified in a fluidized-bed reactor at a relatively low temperature. Gaseous material and char produced in the fluidized-bed reactor are introduced into a high-temperature combustor, and low calorific gas or medium calorific gas is produced in the high-temperature combustor at a relatively high temperature. The fluidized-bed reactor preferably is a revolving flow-type fluidized-bed reactor. The high-temperature combustor preferably is a swirling-type high-temperature combustor.

Abstract: An apparatus and method for processing materials in a batchwise or continuous fluidised bed, such as a drier, in which the fluidised bed is subdivided into a plurality of smaller areas, to each of which two separately controlled gas flows are provided. The first lower gas flow is provided to the bed preferably all of the time, and is sufficient at least to maintain the bed in an expanded state. The second higher gas flow is provided to each separate area of the bed in sequence by means of a rotary valve arrangement, and is high enough to induce fluidisation in the bed, but not high enough to induce significant solids loss by entrainment in the offtake gas. The higher flow sequence can be chosen to provide almost any desired sequence to the separate parts of the bed. The sequence can be chosen to induce a travelling wave within the bed which can be across or along the bed, and can be skewed relative to the sides of the bed.

Abstract: The oblique bed wall (6) of the furnace main unit (1) is inclined in downward direction towards the ash discharge outlet (5). Oblique side walls (24R, 24L) are formed in the right and left side walls (1c, 1d) on the inlet (4) side of the furnace main unit (1), and fluidized bed material (S) blown up from the side fluid layers (RS, LS) is guided into the central fluid layer (CS). The fluidized bed material (S) is caused to circulate in succession from the central fluid layer (CS) at the inlet (4) side towards the central fluid layer (CS) at the ash discharge outlet (5) side towards side fluid layers (RS, LS) at the ash discharge outlet (5) side towards side fluid layers (RS, LS) at the inlet (4) side towards central fluid layer (CS) at the inlet (4) side, by dispersive air emitted from dispersive air pipes (21A, 21B, 25). In this way, the fluidized bed material (S) is caused to circulate in virtually a horizontal plane without partitioning walls.

Abstract: The waste material is degasified under the action of heat in a pyrolysis chamber (2). The volatile degasifying products are subjected to afterburning with supply of oxygen in an afterburning chamber (4a or 4b or 4c) designed as a fluidized-bed reactor. The solids discharged from the afterburning chamber (4a or 4b or 4c) are separated off from the flue gas stream in a dust separator (8) and, preferably cooled in an external fluid-bed cooler, are recycled to the afterburning chamber (4a or 4b or 4c). The temperatures of above 2500.degree. C., which are produced in the afterburning of the carbonization gases having a high heating value (minimum 8000 kJ/m.sup.3 (S.T.P.), can be controlled.

Abstract: Semi-permeable screens are installed in a pulverized coal burning boiler and rotatably driven by a high speed rotatable shaft. A first one of the screens is located above the main combustion zone of the boiler and a second one of the screens is located directly under the burnout zone of the boiler. The underside of the first rotating screen repels the larger and slower burning fuel particles that escape from the main combustion zone so that they are recycled for a complete burn-out. The smaller glowing particles suspended in the combustion gases pass through the first rotating screen and are micronized by the comminution effected by the spiral vortexes generated above this first screen. The second rotating screen positioned under the burnout zone provides for mixing and comminution of the gases and burning coal particles respectively. The vortexes generated by the screens homogenize the heat distribution in the upwardly moving stream of gas and solid particulates.

Abstract: A continuously operated boiler heated with a pressurized circulating fluidized bed firing consists of a fluidized bed burner chamber (1) and one or more cyclones (5) connected in series after the fluidized bed burner chamber (1) and on the flue gas side. A fluidized bed cooler (12) is connected in series after each cyclone (5) which cooler is connected by way of a dip pot (8) with the solids output of the cyclone on one hand and with the fluidized bed burner chamber 91) on the other hand. A return conduit (10) is connected with the dip pot (8) which opens into the fluidized bed burner chamber 91). Pressure vessels (18, 19) house the fluidized bed burner chamber (1), the cyclone (5) and the fluidized bed cooler 912). The fluidized bed cooler (12), the cyclone (5) and the dip pot (8) are thereby combined into a unite which is housed in the common pressure vessel (19).

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

Abstract: A fluidized bed reactor includes a plurality of nozzles for introducing a fluidizing gas wherein at least some of the nozzles are provided with a plate proximate to the nozzle inlet which redirects the flow of the fluidizing gas to the nozzles. By providing a plate at the inlet of the nozzles the following is accomplished. Even flow distribution of the fluidizing gas through the nozzle is achieved. The pressure drop through the nozzle remains relatively high thus insuring good fluidizing gas acceleration which eliminates the adherence of the fines to the interior surface of the nozzle.

Abstract: A water tube wall or heat transfer surface for use in a circulating fluidized bed combustor or reactor having reduced erosion at a transition between a protective refractory material and the upper wall.

Abstract: A fluidized bed apparatus having a gas distribution plate containing a plurality of tuyeres, which tuyeres provide a uniform gas flow from the gas chamber of the apparatus to the reactor chamber of the apparatus and prevents particulate matter of the fluidized bed from backsifting from the fluid bed chamber through the gas distribution plate to the gas chamber. The tuyeres are secured in openings in the gas distribution plate and comprise a porous plate and preferably a perforated plate superposed within a flanged two-component structure which two components are screwed together or otherwise secured together to form the tuyere.

Abstract: To cool and clean flue gases from a furnace of a waste incineration plant, the flue gases are fed to a fluidized-bed reactor (6) as fluidizing gases in a first stage (1), into which solid sorbents are simultaneously introduced to remove gaseous pollutants. Solids discharged from the fluidized-bed reactor (6), together with the unused sorbents, are preferably recirculated via a fluid-bed cooler (15). Whereas in the first stage (1), at temperatures above 600.degree. C., optimum conditions, in particular for removing SO.sub.2, are created, the flue gases are further cooled and treated in a second stage (2a, 2b, 2c). In a second circulating fluidized bed, at temperatures below 600.degree. C., excellent conditions are created for HCl removal. In addition to the optimum gas cleaning, efficient cooling is also achieved, corrosion problems on heat-transfer surfaces also being solved.

Abstract: An improved fluidized bed reactor having a reactor shell and at least one reactor subsystem within the shell, the reactor subsystem having a reaction chamber and a wall, the improvement comprising at least one fluidizing gas distributor associated with the reactor subsystem and positioned below the reaction chamber and supported by the wall, the distributor comprising a top portion, a bottom portion, and a sidewall contiguous with the top and bottom portions to define an interior, a plurality of tuyeres attached to the top portion of the distributor to provide gaseous communication between the reaction chamber and the interior, and an inlet in the bottom portion for introducing a fluidizing gas to the interior.

Abstract: A dual fuel gasification-combustion system (44)with multi-stage fluidised bed gasifier (32)for complete carbon conversion of the input fuel using single or combineable oxidants and sulphur sorbents to produce a clean fuel gas and combustion gas at any pressure for use with boilers gas turbines,or, combined cycle gas-steam turbines.The application (44) for combined cycle power includes a multi-stage gasifier (32)with design number of stages to maximise carbon conversion of input liquid or solid fuels being connected to a gas turbine (53)via gas cleaners (45),(47)and afterburner (46)to produce a clean combustion gas entering the gas turbine. The system has coolant conduits (6) in the gasifier and in the afterburner at (50) and generated steam from the boiler (54) for the steam turbine (51).

Abstract: To a fluidized combustor bed there is passed particulate fuel via a fuel flow distributor which comprises a vessel for receiving a particular fuel from a fuel storage. The fuel is fed into the vessel of the fuel flow distributor from the fuel storage, whereupon the fuel is fluidized in a bed above a bed bottom in the vessel of the fuel flow distributor. The fuel flow distributor comprises at least two feed pipes with associated inlets located adjacent the surface of the bed in the fuel flow distributor, where fluidization gas which leaves the vessel via a feed pipe feeds out fuel to at least one nozzle is in the bed of the combustor. Additional gas is supplied to the feel pipes at the inlets thereof, such that the flow of fuel through an individual feel pipe can be controlled by controlling the gas flow supplied to the inlets of the respective feed pipes.

Abstract: A modular ceramic protective part for a metal blowing grate (1) in a catalytic cracker regenerator, comprises a tubular nozzle portion (4) and a flange portion (6) extending substantially perpendicularly from one end thereof. The part is useful in chemical engineering.

Abstract: A combustion method and apparatus in which combustible matter, e.g., waste matter, coal, etc., is gasified to produce a combustible gas containing a sufficiently large amount of combustible component to melt ash by its own heat. A fluidized-bed furnace has an approximately circular horizontal cross-sectional configuration. A moving bed, in which a fluidized medium settles and diffuses, is formed in the central portion of the furnace, and a fluidized bed, in which the fluidized medium is actively fluidized, is formed in the peripheral portion in the furnace. The fluidized medium is turned over to the upper part of the moving bed from the upper part of the fluidized bed, thus circulating through the two beds. Combustible matter is cast into the upper part of the moving bed and gasified to form a combustible gas while circulating, together with the fluidized medium.

Abstract: A circulating fluidized bed processor has a processor enclosure at least partially defined by a front wall and a rear wall spaced away from the front wall. A bottom wall is connected between the front and rear walls and a mechanism is provided for supplying primary air through the bottom wall for fluidizing a circulating bed in the enclosure. Another mechanism is provided for recirculating the bed from a top of the enclosure back to the enclosure. One or more secondary air plenum(s) are provided in the enclosure between the front and rear walls for supplying secondary air into the fluidized bed, above the bottom wall, so that secondary air reaches deep into the enclosure. The plenum(s) are formed of a waterwall which has a plurality of openings therein to allow communication of gases and solids therethrough from one side of the waterwall to the other.

Abstract: A fluidized bed heat treatment apparatus is provided to be heated by combusting fuel gas in a manner to minimize or prevent the exhaust of carbon monoxide, the apparatus including a retort containing refractory particles to be fluidized, a first inlet in a lower region of the retort for introducing fuel/air mixture into the retort, a second inlet in a lower region of the retort for introducing secondary air into the retort, a temperature sensor located above the first and second inlets, a flame initiator located above the refractory particles, an externally located mixer to mix fuel and air in desired proportions and to supply same to the first inlet, and a control device arranged to control said externally located mixer in response to temperatures sensed by said temperature sensor whereby when the temperature sensor is below a predetermined temperature indicative of the bed being substantially not fluidized, a stoichiometric fuel/air mixture is supplied to the first inlet and when the temperature sensor sens

Abstract: The fuel is fed into a circulating fluidized bed steam generator using a feed system involving an air swept chute using secondary combustion air to suspend and carry the fuel into the fluidized bed combustor. The fuel is fed to the air swept chute through a gravity feed chute at a steep angle. The air swept chute is lined with an abrasion resistant material.

Abstract: A method and apparatus for treating refuse by non-combustibly shrinking plastics in the refuse. The trash is heated to a temperature of at least 250.degree. to 500.degree. for a minimum period of time. A rotatable chamber heats the refuse and transports the refuse for the minimum period of time. An operator controls the rate of rotation of the chamber and thus the time of heating in accordance with the moisture content of the refuse. A steam/air mixture used as a heat medium serves to kill bacteria in the refuse in addition to shrinking and drying the refuse.

Abstract: A fluid bed for producing and/or processing a particulate material, said bed comprising a container constituted by two convex parts, through which a perforated plate for supporting a fluidized particle layer is fixed. Nozzles for injection of a treatment liquid are provided in the perforated plate and above the plate filtering means are provided for removal of particles entrained by the fluidizing gas.

Abstract: A heat exchanger and a fluidized bed combustion system and method utilizing same in which the heat exchanger includes a plurality of stacked sections. The sections include an inlet section for receiving the particles and a plurality of stacked sections and are arranged in such a manner that the particles are introduced into an upper level of the sections and pass through these sections to a lower level of sections before returning to the furnace. A portion of the stacked sections contain heat exchange surfaces for removing heat from the particles, and a multi-sectioned outlet compartment is provided to receive the separated particles from the heat exchange sections and directly from the inlet section and pass the particles back to the furnace.

Abstract: An improved CFB reactor or combustor arrangement has at least a first and a second group of impact type particle separators or U-beams with cooling surfaces located adjacent and immediately upstream of the second group of U-beams which serve to cool flue gas/solids flowing through the CFB before it reaches the second group of U-beams. By reducing the gas temperature in the vicinity of and entering the second group of U-beams, the U-beams can be made of less expensive materials and are thus less expensive to produce and maintain. The heat absorbed by the local cooling surfaces can be applied to heat a working fluid supplied to a turbine or other process.

Abstract: Waste treatment. The installation for implementing the method comprises: a furnace (1) defining a confinement enclosure (2) for a fluidized bed (3) of particulate matter; means for recirculating the particles of the bed; means (28) for mixing, coating, and drying the recycled particles and the waste; and means for feeding the furnace from the means (28). The invention is applicable to treating moist waste.

Abstract: A drainable discharge pan apparatus for an impact type particle separator used on circulating fluidized bed (CFB) boilers employs a plurality of funnel shaped discharge pans located at a lower end of each of the impingement members in the impact type particle separator. The funnel shaped discharge pans prevent accumulation of collected particles thereon, allowing particles collected by the impingement members to fall therethrough, while preventing bypassing of flue gas around lower ends of the impact type particle separator. The outlet ends of the funnel shaped discharge pans provide substantially the same open area for the collected particles to fall therethrough as exists within each associated impingement member.

Abstract: A fluidized bed boiler bottom with an ash cooling and removal system has a water-cooled tube panel floor with fluidization bubble caps above a windbox, and a structural support and at least one hopper, each of the at least one hoppers with a bed ash cooler region and drain control system positioned beneath the tube panel floor. The hoppers are formed from cooled enclosure tubes and have sloped upper walls and lower troughs having vertical walls. Standpipes are provided through the tube panel floor down into the troughs at the bottoms of the hoppers. The standpipes may be arranged in an H-pattern in the tube panel floor and subsequently channel several flowpaths together into fewer standpipes closer to the troughs. Solids flow through the standpipes is controlled by operation of fluidizing nozzles located underneath the standpipes. Pulsing the flow of air through the fluidizing nozzles prevents or allows solids to flow through the standpipe from the bed.

Abstract: Waste is burnt in a furnace chamber (1). The oxygen-containing flue gases resulting in this process are introduced into a fluidized bed in an afterburning chamber (5) and reburnt. Solids discharged with the flue gases from the afterburning chamber (5) are separated from the flue gases in a dust separator (9) and recycled to the afterburning chamber (5), so that a circulating fluidized bed is formed, which produces a very homogeneous temperature distribution in the afterburning chamber (5) and at the same time permits highly efficient cooling of the flue gases. A secondary oxygen feed for the afterburning is dispensed with, which enables a decrease in size both of the afterburning chamber (5) and also of the downstream heat-recovery and gas cleaning devices and improvement in efficiency resulting therefrom.

Abstract: The present invention provides a system and method (1) for reducing the amount of air toxic elements, particularly mercury (16), in concentrations down to and including trace levels, from a flyash (2) laden combustion gas stream (4). The method includes a step of combusting a fuel (14), often coal or solid waste to form flyash, and a step to concentrate the interaction of the flyash (2) in the combustion gas stream (4) for use as a sorbent.

Abstract: A control scheme for large circulating fluidized bed steam generators (CFB) wherein direct control is effected therewith over the temperature of the large circulating fluidized bed steam generators (CFB) and wherein independent control is effected therewith over the final superheat steam temperature of the large circulating fluidized bed steam generators (CFB) as well as over the final reheat steam temperature of the large circulating fluidized bed steam generators (CFB).

Abstract: A recovery boiler for combusting spent liquor from cellulose cooking while at the same time recovering chemicals. The recovery boiler is constructed for so-called "rotafire" combustion and the speed of rotation of the secondary air has been increased by a constriction of the boiler being arranged at the tertiary air level. The invention also includes a process for using the boiler which is based on certain ports through which the secondary air is blown in being provided with air which is at a higher pressure than that at the other ports on the same level, thereby achieving a higher inflow velocity than from the other ports.

Abstract: Technology for treating industrial and domestic waste which can be applied in the chemical industry as well as in the power generation sector as a way of using plastic and polymer waste. The method involves: melting down the plastic waste in an atomsphere of superheated steam and thermal destruction of the waste at a temperature of 400.degree.-500.degree. C. on a multi-layered inert material whose particles diminish in size, layer by layer in the direction of flow of the melt, from 3.83 to 0.12 mm; and the removal and condensation of the gaseous products.

Abstract: In a power plant with combustion of particulate fuel in a fluidized bed, unburnt particles are after-burnt in a burner which is based on the principle of vortex collapse and coarser particles are separated in connection with the after-burning. Such a burner may be designed as a double-cone burner, wherein unburnt fuel particles are burnt. Larger particles move around in a helical movement inside the extension of the burner cone. A coarse particles separator integrated with the burner, is arranged and comprises a circular gap which is located near the extension of the burner cone and which collects coarser particles rotating at the side of the combustion zone of the burner. These separated particles, collected by the circular gap, are forwarded to a space which surrounds the burner and from where the separated coarser particles are returned to the primary combustion space, for example, to the fluidized bed in the plant.

Abstract: In a method for reducing NOx in the flue gas a coal water slurry is injected into the furnace above the primary combustion zone into a region having a temperature from 1800.degree. F. to 2700.degree. F. The slurry is preferably injected through atomizers and through injectors that introduce a continuous stream. Lime, ammonia, urea and completion air can also be injected.

Abstract: In an improved method of treating foul water, the solids that are produced during the process of treatment of foul water such as wastewater or liquid sludges are treated with a heat treatment apparatus and the resulting thermal energy and/or gas is utilized in the treatment of said foul water. The foul water may be subjected, directly and/or after a treatment, to a filtration step using a filter packed with nonflammable particulate matter such as sand, and the trapped solids are fed into a fluidized-bed heat treatment apparatus such as a fluidized-bed incinerator or gasification furnace and, thereafter, the nonflammable particulate matter in the heat treatment apparatus is returned to the filtration step. The foul water can be treated with effective utilization of the energy of the organic matter in the foul water or the solids that are produced during the process of its treatment.

Abstract: A grate assembly for a fluidized bed boiler comprises a number of parallel sparge pipes or the like extending side-by-side in a substantially horizontal plane and provided with elements for supplying fluidizing air from within the sparge pipes or the like into a combustion chamber located above the grate assembly. The discharge of some of the fluidized bed materials is effected through an aperture system formed between the adjacent sparge pipes into a receiver unit fitted below the grate assembly. The sparge pipes are provided with a cooling medium circulation by means of a duct assembly.