Abstract: A once-through boiler system for use in conjunction with a combustion chamber includes a water inlet through which water having a high total dissolved solids content is supplied to the system, at least one tubular preheating surface for preheating the water as the water flows through the preheating surface, and at least one tubular evaporation surface for further heating the water flowing therein to produce a steam/water mixture. The preheating surface is disposed downstream from the inlet and encloses at least part of the combustion chamber, and the evaporation surface is disposed within the combustion chamber, downstream from the preheating surface.

Abstract: A combined cycle power generation plant includes a boiler for producing steam, the boiler including a furnace for combusting first fuel to produce flue gas, a back-pass for receiving the produced flue gas and a flue gas duct for passing the flue gas from the back-pass to the environment, a process gas supply for supplying processed gas to the furnace, a steam turbine for receiving and being driven by the steam to generate power, a combustor for combusting a second fuel to produce exhaust gas, a gas turbine for expanding the exhaust gas from the combustor to generate power and for passing the exhaust gas to the process gas supply. The boiler is designed to provide effective steam production and low emissions to the environment in first operating conditions of the combustor when using exhaust gas alone or as a major portion of process gas being supplied to the boiler.

Abstract: A fluidized bed combustion system in which a separator receives a mixture of flue gases and entrained particulate separated material from a fluidized bed in a furnace. A pressure seal valve connects an outlet of the separator to the furnace or a fluidized bed heat exchanger disposed adjacent the furnace for recycling the separated particulate separated material back to the furnace. The pressure seal valve includes a downflow leg, and upflow leg and a horizontal leg connecting the downflow leg to the upflow leg. A horizontal overflow leg is connected to the upflow leg and at least two return legs connect the overflow leg to the furnace. The separated material from the separator passes through the legs of the pressure seal valve and sometimes through a heat exchanger (if included) before reentering the furnace.

Abstract: An apparatus and method of operating a steam generator tube bank are disclosed in which a water drum of a typical steam drum/water drum combination is replaced with a plurality of smaller readers to permit the use of rapping, or mechanical rappers, to clean the tubes extending between the steam drum and the headers. The steam generator tube bank of the present invention comprises a steam drum or collecting header, a plurality of headers extending below the steam drum, and a plurality of tubes extending between the steam drum and the headers and placing the steam drum and headers in fluid flow communication. The headers are sized to permit debris or deposits which accumulate on the tubes to be removed by rapping the headers, thereby inducing vibration of the headers and the tubes. The tubes are arranged in rows, and the headers are arranged to form rows of axially-aligned pairs of headers.

Abstract: A fluidized bed combustion system and method in which a recycle heat exchanger is disposed integrally with the furnace of a fluidized bed combustor. The recycle heat exchanger includes a plurality of stacked sections for receiving the recycled solids and are arranged in such a manner that the recycled solids 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 solids therein while another portion does not. The solids in the various sections are selectively fluidized to control the flow of the solids through the sections to control the temperature of the solids accordingly.

Abstract: An apparatus and method of operating a fluidized bed reactor for combusting refuse derived fuel is disclosed. The reactor includes a fluidized furnace section 30 and stripper/cooler section 80. A downwardly sloping grid 28 extends across the furnace section 30 and stripper/cooler section 80 to a drain 78 in the stripper/cooler section 80, and directional nozzles 38 disposed in the grid fluidize the beds in the furnace section 30 and stripper/cooler section 80 and forcibly convey relatively large particulate material across the grid 28, through the furnace section 30 and stripper/cooler section 80, and to the drain 78 for disposal. A refractory layer 36 is provided along the grid 28 surface to reduce the height of the nozzles 38 within the furnace section 30, thereby helping to prevent relatively large particulate material from becoming entangled with or stuck to the nozzles 38.

Abstract: An apparatus and method of operating a fluidized bed reactor for combusting refuse derived fuel is disclosed. The reactor includes a fluidized furnace section 30 and stripper/cooler section 80. A downwardly sloping grid 28 extends across the furnace section 30 and stripper/cooler section 80 to a drain 78 in the stripper/cooler section 80, and directional nozzles 38 disposed in the grid fluidize the beds in the furnace section 30 and stripper/cooler section 80 and forcibly convey relatively large particulate material across the grid 28, through the furnace section 30 and stripper/cooler section 80, and to the drain 78 for disposal. A refractory layer 36 is provided along the grid 28 surface to reduce the height of the nozzles 38 within the furnace section 30, thereby helping to prevent relatively large particulate material from becoming entangled with or stuck to the nozzles 38.

Abstract: A reactor in which a plurality of vertical panels are disposed in a vessel and are constructed and arranged so as to form three combustion cells. Three of the panels each form a common wall between adjacent cells, and each cell is heated by a fluidized bed.