Tri-sector regenerative oxidant preheater for oxy-fired pulverized coal combustion

Abstract

A tri-sector regenerative oxidant preheater apparatus, method and arrangement for utilization with oxy-fired pulverized coal combustion power plants. The preheater includes a stationary housing and a rotor rotatably mounted in the housing. Sector plates are located at the axial ends of the rotor and divide the preheater into a flue gas sector, two primary oxidant sectors, and a secondary oxidant sector interposed between the two primary oxidant sectors. A primary oxidant fan is located downstream of the preheater to create a negative environment in the primary oxidant sectors. During operation of the preheater, the environments of the two primary oxidant sectors and the flue gas sector are at about the same negative pressure, and thus there is very limited leakage between the oxidant side and the flue gas side of the preheater. The environment of the secondary oxidant sector is at a positive pressure and leakage to the negative environment of the primary oxidant sectors will be that of secondary oxidant to primary oxidant with no loss secondary oxidant to the gas side of the preheater.