燃煤电厂颗粒物测定方法研究

Study on the determination of particulate matter in coal-fired power plants

燃煤电厂排放的颗粒物有3类:可过滤颗粒物(含细颗粒物)、可凝结颗粒物和可溶盐,国内对其测试方法的研究还较薄弱。笔者系统分析了3类颗粒物的测定方法,针对性地提出准确测定手段及控制要点并分别开展了现场实测验证。凭借精密度较高的测试仪器及开展空白试验等,可保证可过滤颗粒物测定结果具有较高精确度;电荷法(ELPI)和重量法(PM-10)的PM2. 5测试结果一致性较好;2级冷凝盘管+异丙醇吸收可实现对SO3的高效捕集,且第2级盘管和异丙醇吸收的SO3占比最高可达40%,建议低浓度测试优先采用该方法;采样枪温度加热到160℃,此时滤膜实际测定的颗粒浓度即为可过滤颗粒物+可溶盐。

There are three kinds of particulate matter discharged from coal-fired power plant:filterable particles(include PM2.5),condensable particulates and soluble salt,and the domestic research on its testing method is still weak.In this paper,the determination methods of three kinds particles were researched,the determination methods and control points of particulate matter were pointedly put forward,and the field measurement and verification were carried out respectively.With high precision test instrument and blank test,the results of filterable particulate matter determination can be guaranteed to have high accuracy.The PM2.5 test results of charge method(ELPI)and gravimetric method(PM-10)are consistent with each other.The 2-stage condensing coil and isopropyl alcohol absorption can achieve the efficient capture of SO3,and the SO3 absorbed by the second stage coil and isopropanol can reach up to 40%.The method is recommended for low concentration tests.When the sampling gun is heated to a temperature of 160℃,the actual particle concentration measured by the filter membrane is filterable particles and soluble salt.