燃煤机组调峰过程中污染物排放特性及控制技术

目的  随着可再生能源在电网中发电比例的逐年提高，火电机组实际运行参数大幅偏离设计运行参数，将造成烟气中的污染物生成量增加，影响尾部烟气处理设备的正常运行，降低污染物的去除效率及机组运行经济性。 方法  文章聚焦于机组调峰过程中的典型污染物排放规律分析及相应排放控制策略，对氮氧化物、硫化物、挥发性有机物、重金属、颗粒物等排放特性的已有研究成果及进展进行分析总结，具体包括选择性催化还原法脱硝技术、湿法脱硫技术、静电除尘技术、催化氧化技术、吸附控制技术等。 结果  在此基础上，得出当下灵活调峰过程中所采用的控制技术及控制策略，并对各类污染物控制技术的经济性进行对比分析，得出灵活调峰过程中影响污染物排放性能及控制成本的因素。 结论  在燃煤机组灵活调峰的实际需求下，应基于各类污染物自身特性，构建合理的污染物停留时间、工作温区、流动及反应过程，开发适用于多污染物脱除的高效、低成本、适应性强的污染物协同脱除技术及工艺。期望文章内容可以为火电机组灵活调峰过程中的污染物排放控制措施提供一定参考。

Emission Characteristics and Control Technology of Flue Gas Pollutants During Peak Regulation of Coal-Fired Units

  Introduction  With the gradual increase in the proportion of renewable energy generation in the power grid, the actual operating parameters of thermal power units deviate significantly from the design parameters, which will increase the amount of pollutants in the flue gas, and affect the regular operation of the flue gas treatment equipment, thus reducing the pollutant removal efficiency and the operating economy.   Method  The analysis of typical pollutant emission characteristics and corresponding control strategies during the peak shaving process of the unit was concerned. The current research results and progress of emission characteristics of NO_x, sulfides, volatile organic compounds, heavy metals, and particulate matter were analyzed and summarized, including selective catalytic reduction technology, wet flue gas desulfurization technology, electrostatic precipitator technology, catalytic oxidation technology, gypsum absorption technology, adsorption control technology, etc.   Result  On this basis, the control technology and control strategy used in the current flexible peak shaving process is put forward, the economics of various pollutant control technologies are compared and analyzed, and the factors influencing the pollutant control performance and costs are obtained.   Conclusion  Under the actual demand for flexible peaking of coal-fired units, it is concluded that under the demand of flexible peak regulation, reasonable pollutant residence time, working temperature range, flow, and reaction process should be constructed based on the characteristics of various pollutants, and pollutant synergistic removal technology characterized by efficient, low-cost, adaptable and suitable for multi-pollutant removal should be developed. It is expected that this paper can provide some reference for the pollutant emission control measures in the flexible peak shaving process of thermal power units.