Abstract: A method of preparing a compound pipe, the wall of which comprises an inner layer of a first material and an outer layer of a second material. Powders of the two materials are isostatically hot pressed to form a cylindrical tubular blank in which the first material forms an inner layer and the second material forms an outer layer, the blank after heating to a suitable temperature being extruded over a mandrel.

Abstract: In a PFBC power plant having a bed vessel containing a bed of fluidizable particulate material enclosed within a pressure vessel and surrounded by compressed combustion air, a gas turbine-compressor unit driven by combustion gases from the bed vessel, a first cut-off valve in a supply conduit for propellent gas to a turbine; a second cut-off valve in the conduit from a compressor to the bed vessel, a third cut-off valve in a by-pass conduit between the turbine and the compressor, and a blow-off valve in a conduit for dumping combustion gases from the bed vessel, a method of controlling such power plant in the event of an operational disturbance in the turbine unit comprises the steps of isolating the compressor-turbine unit from the bed vessel by closing the first cut-off valve in the supply conduit and the second cut-off valve in the conduit from the compressor to the bed vessel, short-circuiting the compressor-turbine unit by opening the valve in the bypass conduit, dumping the combustion gases by opening t

Abstract: The invention relates to a method for manufacturing a blade or vane of a turbine. A master of the blade or the vane is made of steel, and silicon rubber is molded around said master. The mold thus obtained is cut open and removed from the master to be used for producing a model of wax or the like, a mixture of graphite powder and a cement then being molded around said model. The model is melted and removed from the graphite mold which is filled with a compacted powder of metal or metal alloy. The mold with the powder compacted therein is isostatically hot pressed and then the mold is removed from the produced molded body by blasting.

Abstract: A power plant with a combustion chamber in which a fuel in burned in a fluidized bed of a particular material, comprises a storage container for the bed material which, upon a load reduction, is removed from the combustion chamber. The storage container is provided with a sieve or a grate which prevents slag lumps formed in the bed material from penetrating into a conduit for the return of the bed material to the combustion chamber. A tube projecting into the storage container forms the sieve.

Abstract: A method of discharging heat from a particulate material in a bed (28) of a combustor (12) in the event of an operational disturbance in a PFBC power plant. Gas from the combustor (12) is cooled in a cooling circuit (69) connected to the combustor (12) and is returned to the combustor (12) where it is allowed to pass through the bed (28). A device for carrying out the method comprises a cooling circuit (69), connected to the combustor (12), with a cooler (72) and a compressor or fan (76) which effects gas circulation through the cooling circuit (69) and the combustor (12).

Abstract: A power plant burning a fuel at a pressure exceeding the atmospheric pressure includes a combustor formed with cooled walls which form a feed water preheater. A by-pass conduit with a control valve for draining feed water is connected to a feed water conduit between the feed water preheater (the combustor walls) and an evaporator in the combustor. This by-pass conduit may be connected to a feed water tank. At a very low load and in the case of a gas turbine trip, the necessary water flow for cooling the walls of the combustor may exceed the requirement of feed water to the evaporator. Under these operating conditions feed water may be drained off ahead of the evaporator through the by-pass conduit.

Abstract: A transport device for pneumatically transporting particulate material from a container which is under pressure to a container which is under a lower pressure, in which successive pressure reduction is achieved by repeated deceleration and acceleration of the particulate material in the gas-particle flow and by diversion of the gas-particle flow. The transport device includes a number of rectilinearly arranged nozzles and cup-shaped containers placed downstream of the nozzles and alternating with the nozzles. The cup-shaped containers receive material flowing out of the nozzles. The containers are arranged such that a channel is formed around the outside walls of the containers through which the particulate material flows to a downstream nozzle.

Abstract: A manifold receives gas streams from a plurality of gas purifiers arranged in parallel. The manifold comprises a plurality of pipe portions wiht a successively increasing diameter forming a main channel in the manifold. A first pipe portion projects into a second pipe portion, whereby, in the gap between the pipe portions a connection channel is formed which is substantially parallel to the main channel. The second pipe portion projects into a third pipe portion, thus forming a gap between the pipe portions and so on. Outlet tube portion from cyclones are connected to the connection channels.

Abstract: A method for improving the corrosion/erosion resistance of Fe-based, Co-based, or Ni-based alloys included in power plants for combustion in a a fluidized bed. The method is characterized in that the surface of the metal alloy is treated in a multi-step combination treatment to provide an adherent and protective surface layer.

Abstract: A method for improving utilization of sulphur-absorbent containing calcium, in a power plant burning fuel in a fluidized bed (12) of particulate material in a combustion chamber (11). When fresh absorbent is prepared it is crushed and the crushed material is subsequently divided into a fine and a coarse fraction. The fine fraction is calcinated, mixed with crushed coal (41) and used as drying agent. The invention also relates to a power plant having equipment (28) for calcinating a fine-particled fraction of fresh sulphur-absorbent, and also equipment for mixing coal (41) and the calcinated absorbent and equipment (46, 48) for feeding the mixture of absorbent and coal into the bed. (FIG. 3).

Abstract: The invention relates to a pressure-relief device in a PFBC power plant with a combustor (12) enclosed in a pressure vessel (10). The device is intended to limit the pressure difference between the combustor (12) and the surrounding space (22) in the pressure vessel (10) and to initiate pressure relief of the pressure vessel (10) out into the atmosphere. Via a conduit (54) with a rupture disc (56), the combustor (12) communicates with one or more blow-off valves (42). If the rupture disc (56) bursts, a sensor (62) indicates this and effects opening of the blow-off valve (42) via signal processing and operating equipment (64). Between the rupture disc (56) and the combustor (12) a perforated diaphragm (60) is provided. In the space between this diaphragm and the rupture disc (56) a layer of particulate, heat-insulating material (58) is provided, which restricts the heating of the rupture disc (56).

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

Abstract: 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: A method for improving utilization of sulphur-absorbent when burning fuel in a fluidized bed of particulate material includes withdrawing partially consumed bed material from the ash chamber of the bed vessel and returning to the combustion chamber of the bed by means of pneumatic transportion using steam as propellant. The steam constitutes a reactant which effects disintegration of the bed-material particles. A power plant burning a fuel in a fluidized bed of particulate material comprises a bed vessel having an air distributor with nozzles for supplying air to a combustion chamber to effect fluidization of the bed and combustion of a fuel. An ash chamber is provided below the air distributor for removal of ash and bed material, and transport means for withdrawing partially consumed bed material from the ash chamber, treating this bed material with steam and returning the steam-treated bed material to the combustion chamber.

Abstract: A gas turbine with at least one fixed guide vane ring (1) with a sealing ring (3) cooperating with a sealing member on the turbine rotor (7). The sealing ring (3) is connected to the guide vane ring (1) through a number of links (19) which are suitably oriented in a substantially tangential direction. The attachment of the sealing ring (3) by means of the links (19) means a perfect centering of the sealing ring (3) relative to the rotor (7) when the guide vane ring (1) expands relative to the sealing ring (3).

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

Abstract: A power plant 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: A fuel burning power plant comprises a bed vessel with a bottom grate which divides the bed vessel into an upper combustion chamber and a lower part with at least one ash chamber. The bed grate consists of parallel air distribution tubes each with air nozzles, between which tubes gaps are provided where bed material may pass from the combustion chamber down to the ash chamber. Below the tubes there is a transverse air distribution chamber. The tubes are connected in groups to the air distribution chamber by a double-walled sleeve extending down from the tubes.

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

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