Abstract:

Combining with the practical operation of a denitrification device in a 300MW unit, blockage in rectifying device, ammonia injection grid, catalyst and air preheater during the running of denitrification device and the corresponding causes are analyzed. It is proposed to optimize the structure and arrangement of the large ash filter, run steam soot blower regularly， adjust the frequency of the sonic soot blower, timely clean up the ash accumulated on steel beams and the deflectors on different layers of the selective catalytic reduction(SCR)denitration device，ensure the flow channels of catalyst and replace catalysts with severe ash deposit. These optimization measures can improve the security and stability of the SCR denitrification devices， which provides reference for prevention and control of the accumulation of ash in SCR denitrification devices of coalfired power plants.

Key words:

coalfired power plant, selective catalytic reduction, blocking problem, improvement