Research on Optimization of Flow Field of Denitration System of 600MW Unit and Modification of Fine Ammonia Injection

Aiming at the uneven distribution of flow field in the denitration system of coal-fired power plant boilers, poor mixing of ammonia and nitrogen, increased ammonia escape, and easy blockage of the air preheater, a flow field optimization and transformation plan was proposed through numerical simulation and added in the flue of the denitration system. Equipped with baffles and static mixers, modified the ammonia injection pipeline in zones, implemented ammonia injection total control and grid balance automatic adjustment control. After the transformation of precise ammonia injection for denitrification, the NOx emission of the unit is stably controlled at 40 mg/Nm3, the steady-state deviation value and other indicators are better than the acceptance standard, and the air preheater differential pressure is effectively controlled.