| 摘要 |
PROBLEM TO BE SOLVED: To enable both of complete combustion of fuel in a riser combustor, and stable heat recovery of high efficiency in a fluidized bed boiler, to be simultaneously achieved.SOLUTION: An oxygen combustion circulation fluidized bed boiler includes an exhaust gas boiler 18 making vapor by introducing an exhaust gas 13 mainly made of carbon dioxide separated by a separator 12, a circulation pump 23 for extracting the exhaust gas 13 at a downstream of an exhaust gas boiler 18 as a recirculated exhaust gas 22, a first gas supply means 26 adjusting and supplying the recirculated exhaust gas 22 to a diffusion chamber 4 to which oxygen 6 of a lower combustion part 1a of a riser combustor 1 is supplied, and forming an allowable high temperature combustion zone 25 in the lower combustion part 1a, and a second gas supply means 29 adjusting and supplying the recirculated exhaust gas 22 to an upper combustion part 1b, and forming a particle temperature adjustment zone 28 in the upper combustion part 1b. The upper combustion part 1b of a diameter larger than that of the lower combustion part 1a is formed on an upper part of the lower combustion part 1a through a diameter expansion part 2, and the second gas supply means 29 is connected to the diameter expansion part 2. |
