安徽省煤电机组超低排放改造及CEMS验收问题分析

对安徽省已提前完成超低排放改造任务的67台（36 490 MW）煤电机组的SO₂、NO_x和烟尘超低排放改造技术路线、改造的经济性、改造后排放浓度及减排量以及改造后3种污染物在线监测系统（CEMS）验收中的问题进行分析。研究表明：安徽省燃煤电厂超低排放改造主要以湿式电除尘、低低温电除尘和超净电袋为核心的3条典型技术路线。1000MW机组改造经济性最高，其次为600MW和300MW机组。超低排放改造对全省电厂烟气污染物减排显著，污染物之间协同脱除效果良好。现行的气态污染物监测仪器、滤尘材料及测试方法均不能很好地满足改造后污染物CEMS验收的测试准确度要求，建议超低排放改造机组的烟尘验收选用低浓度粉尘测量自动取样系统和设置空白实验修正；SO₂验收需采用紫外或红外烟气分析仪，采样管路需要高温伴热；NO_x验收应根据SCR脱硝出口和总排口NO_x浓度测试数据相互佐证。

Analysis of the Ultra-low Emission Transformation and CEMS Acceptance of Coal-fired Power Plant in Anhui Province

The transformation of ultra-low emissions of 67 coal-fired generating units (36 490 MW) has completed in Anhui Province. On this basis, the technical routes of ultra-low emissions of SO₂, NO_x and dust, the economics of the retrofit, the emissions concentrations and emission reductions after retrofit, as well as the problems in the CEMS acceptance of the three types of pollutants were analyzed. The research shows that the ultra-low transformation of coal-fired power plants in Anhui Province mainly follows three typical technical approaches, which are wet electrostatic precipitator, low-temperature electrostatic precipitator and super net electric bag. The 1 000 MW units have the highest economical efficiency, followed by the 600 MW units and 300 MW units. The ultra-low transformation has a remarkable effect on the emissions reduction of the flue gas pollutants in the power plants of the province, and the synergistic removal of the pollutants is effective. However, the current gaseous pollutant monitoring instruments, dust filter materials and testing methods cannot meet the test accuracy requirements of the modified CEMS after transformation. Therefore it is suggested that the low-concentration dust measurement automatic sampling system and blank experiment correction be used for the ultra-low transformation units. In addition, it is recommended to use ultraviolet or infrared smoke analyzer for SO₂ acceptance, and high temperature heating for the sampling pipeline respectively. NO_x acceptance should be based on both the test data of the SCR denitrification outlet and the total discharge NO_x concentration test.