超低排放背景下煤电机组氨管控存在的问题及对策探析

近年来,我国大气污染防治成效显著,煤电机组超低排放政策实施对此做出了突出贡献。氮氧化物是煤电机组超低排放中的重要控制指标之一。然而,受现有氮氧化物排放监测和喷氨控制技术的精度、反馈时效等因素的限制,为提高脱硝效率保证性,电厂在实际运行中存在过量喷氨现象,未完全反应的氨进入大气后可能造成二次颗粒物增加。针对这一现象,本文回顾了我国火电行业氮氧化物排放标准和治理措施的演化及实施效果,对煤电机组氨排放现状和存在的问题进行了深入分析,提出在推进氮氧化物超低排放过程中应开展脱硝过量喷氨现状调研,鼓励企业开展脱硝系统优化,加强复杂烟气环境下氨监测技术研发,完善脱硝氨逃逸日常环境监管,推动氨排放全生命周期转化规律基础研究和大气环境效应评估,进一步提升煤电机组超低排放政策实施的综合环境效益,也对其他行业超低排放政策推进起到示范作用。

Problems and Countermeasures of Ammonia Emission Control in CoalFired Power Plants Under Ultra-low Emission

In recent years, China has achieved remarkable results in the prevention and control of air pollution, and the implementation of the Ultra-low Emission policy for coal power plants has made outstanding contributions to this. Nitrogen oxide is one of the key indicators in the ultra-low emission of coal power plants. However, due to the limitations of the existing nitrogen oxide emission monitoring and ammonia injection control technologies, such as the accuracy and feedback timeliness, some power plants inject excessive ammonia during daily operation, in order to guarantee the denitration efficiency. Therefore, ammonia that is not involved in the chemical reaction enters into the ambient air, which may cause the formation of secondary particles to increase. This article reviews the evolution and implementation effects of nitrogen oxide emission standards and governance measures in China''s thermal power industry, then conducts an analysis of the current status and problems of ammonia emissions from coal-fired power plants and finally proposes some countermeasures and suggestions to improve the management and control of ammonia emissions in the denitrification process, so as to enhance the environmental benefits of Ultra-low Emission policy and play a demonstrative role for other industries.