. Circulating Fluidized Bed Cycle boilers Several hundred large CFBC boilers worldwide Jacksonville 300 MWe CFBC –coal, etc.- largest units Provence, France 250MWe lignite (high Ca) Two 250 MWe CFBC boilers in Korea (Anthracite) Bubbling PFBC Standard type is a bubbling PFBC in a pressure vessel– Operating pressure (1 to 1,5 MPa) Coal fired with dolomite addition Operating temperature (800- 900ºC) Heat transfer controlled by in-bed heat exchangers (load following by changing bed height) Deep beds (3-4 m )
PFBC Operational Units Cottbus, Germany (71 MWe) Vartan, Sweden (Two units, total 135 MWe) Karita, Japan (360 MWe) New Plants? Possibly a large plant in China Sulphur Capture In atmospheric FBC CaCO 3 = CaO + CO 2 Produces a porous particle (50%), which gradually fills up with CaSO 4, limiting overall conversion to about 30-40% In pressurized FBC CaCO 3 + ½ O 2 + SO 2 = CaSO 4 + CO 2
The development of coal utilization high efficiency power generation technology is an urgent issue from the viewpoints of reduction in greenhouse gases and of resource saving. Technology A-PFBC is a further advanced technology of PFBC (pressurized fluidized bed combustion). That is, the development aimed to increase the temperature at inlet of gas turbine, (from about 850 o C to about 1,350 o C), and to recover high temperature steam. To attain higher efficiency of power generation (about 46% of net efficiency; about 40% for the current coal fired power plants) by the combination of PFBC with the fluidized bed gasification technology.