Abstract: In order to further reduce the operation cost of the power plant,a new technology for the integration of denitration and boilers has been formed.The key points and difficulties of the gas-gas heat exchanger in boiler coupling arrangement are mainly introduced.The characteristics of two kinds of structures of the gas-gas heat exchanger are comparative analyzed,and the results show that the air chamber structure fixed on the wall at the inlet and outlet of heat exchanger has the advantages of small expansion deviation,simple structure arrangement and installation,and good economy compared with the header structure with long elbow.