Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23L—SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
  • F23L5/00—Blast-producing apparatus before the fire
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
  • F01K23/00—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids
  • F01K23/02—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled
  • F01K23/06—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle
  • F01K23/061—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle with combustion in a fluidised bed
  • F01K23/062—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle with combustion in a fluidised bed the combustion bed being pressurised

Definitions

• the invention relates to a method of improving the accessibility of a PFBC plant having a compressor for pressurizing the pressure vessel of the PFBC plant.
• the turbine unit will be of a less complicated structure and moreover more reliable if the compressor is driven directly from the turbine shaft but since such single shaft turbine units, including the compressor, rotate at a constant rpm the intake air volume per time unit ( ⁇ r/s) of the compressor always will be constant ⁇ which means that also the air mass per time unit (kg/s) always will be constant disregarding the change of the mass flow rate due to existing variations in the density of the intake air (the outside air) .
• the method of the invention includes the characterizing features of claim 1.
• the plant includes a gas generator of PFBC type which comprises a pressure vessel 10 including a com- bustion chamber 11 having one or more fluidized beds to which pressurized air is supplied - fluidizing air and combustion air - from the pressure vessel, and having a flue gas outlet 12.
• a gas generator of PFBC type which comprises a pressure vessel 10 including a com- bustion chamber 11 having one or more fluidized beds to which pressurized air is supplied - fluidizing air and combustion air - from the pressure vessel, and having a flue gas outlet 12.
• steam is produced which is supplied to a turbine 14 in a single shaft turbine unit which is connected to an electric generator 15 for production of electric power.
• the single shaft turbine unit also comprises a compressor 16 which is driven by the steam turbine 14 or by an expansion turbine wherein the flue gas from the combustion chamber 11 is allowed to expand, and this compressor is connected at the pressure side thereof to the pressure vessel 10, the suction side of the com ⁇ pressor taking air from the surroundings via a single stage expansion turbine 17 which is also connected to the shaft of the turbine unit.
• the turbine 17 has symmetric blade profiles and is provided with a ring 18 of rotatable inlet vanes.
• the ring of vanes is adjusted to provide a relatively great reduction of the air flow.
• the air taken in by the compressor 16 then will expand in the turbine 17, causing a pressure drop upstream of the compressor and thus a lower density (in relation to the surrounding air) of the air taken in by the compressor. Since the compressor rotates at constant rpm and thus always takes in the same volume flow ( ⁇ /s), the mass flow (kg/s) taken in will be correspondingly lower as compared with the mass flow that should be taken in by the compressor when the air is taken directly from the surroundings and not via the turbine 17.
• the expansion turbine will operate as a compressor, i.e. as a supercharger of the compressor 16, which means that the compressor 16 will take in air at a higher pressure and thus will supply a higher mass flow to the pressure vessel 10.
• This adjustment is thus to be used when the PFBC plant shall operate at full load.
• the adjustment of the ring of vanes 18 can be effected rapidly with a following rapid change of the mass flow from the compressor 16 which means that the accessibility of thet plant will be high because the pressure vessel 10 can be pressurized, loaded, rapidly to the extent required in order to change the plant from partial load to full load.
• An acceptable efficiency, i.e. maintenance of sub ⁇ stantially the same excess air factor, over the total load range of the PFBC plant can be obtained by properly dimensioning the compressor 16 and the turbine 17, which falls within the knowledge of the average man skilled in the art.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Supercharger (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)
• Fluidized-Bed Combustion And Resonant Combustion (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20380146

Family Applications (1)

Country Status (7)

Families Citing this family (1)

Citations (5)

• 1990
  • 1990-08-14 SE SE9002639A patent/SE501736C2/sv not_active IP Right Cessation
• 1991
  • 1991-08-12 JP JP3514010A patent/JPH05509389A/ja active Pending
  • 1991-08-12 DE DE19914191937 patent/DE4191937T/de not_active Withdrawn
  • 1991-08-12 WO PCT/SE1991/000528 patent/WO1992003687A1/en not_active IP Right Cessation
  • 1991-08-12 ES ES09250017A patent/ES2087810B1/es not_active Expired - Lifetime
• 1993
  • 1993-01-29 GB GB9301846A patent/GB2265187B/en not_active Expired - Fee Related
  • 1993-02-12 FI FI930622A patent/FI96717C/fi active

Patent Citations (5)

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