Abstract: In an oxygen mixer for an oxygen combustion boiler, circulating exhaust gas heated in a rotary preheater is mixed with oxygen. Resultant mixed gas is guided to a boiler furnace through a combustion gas duct having bends. At the bend closest to the rotary preheater in the combustion gas duct, an oxygen injection nozzle is arranged to have a plurality of injection ports for injection of oxygen into circulating exhaust gas.

Abstract: Provided is a gas separation apparatus advantageous in suppression of increase in pressure loss and achievement of reduced size and weight, thereby reducing costs. The gas separation apparatus causes an absorbent to flow down along the surface of a packing arranged in a treatment chamber, and supplies to the treatment chamber a gas to be treated which contains a target gas component, and then causes the gas to be treated and the absorbent flowing down along the surface of the packing to come into gas-liquid contact. Thus the target gas component contained in the gas to be treated is absorbed into the absorbent and separated or recovered from the gas to be treated. The packing has at least one packing unit configured by a plurality of expanded metal plates standing vertically and being aligned.

Abstract: In an oxygen mixer for an oxygen combustion boiler, circulating exhaust gas heated in a rotary preheater is mixed with oxygen. Resultant mixed gas is guided to a boiler furnace through a combustion gas duct having bends. At the bend closest to the rotary preheater in the combustion gas duct, an oxygen injection nozzle is arranged to have a plurality of injection ports for injection of oxygen into circulating exhaust gas.