Oxyfuel Combustion Boiler Plant and Operation Method of Oxyfuel Combustion Boiler Plant

摘要

An oxyfuel combustion boiler plant comprising:a boiler having an air separation unit for manufacturing oxygen by separating nitrogen from air, a burner for burning the oxygen supplied from the air separation unit and pulverized coal, and a primary system pipe for supplying the pulverized coal to the burner, exhaust gas recirculation system pipe for supplying combustion exhaust gas discharged from the boiler to the primary system pipe, a carbon dioxide capture unit for capturing carbon dioxide in the exhaust gas discharged from the boiler, the oxyfuel combustion boiler plant is further comprising: an oxygen buffer tank disposed on a downstream side of the air separation unit; an oxygen supply pipe for supplying oxygen to the primary system pipe of the burner from the oxygen buffer tank; and a nitrogen supply pipe for supplying a part of nitrogen generated from the air separation unit or an air supply pipe for supplying air from outside which is connected to the oxygen supply pipe on a downstream side of the oxygen buffer tank and on an upstream side of a junction of the primary system pipe.