600MW燃煤电厂痕量元素排放特性实验研究

使用USEPA Method 29方法对600MW燃煤电厂SCR、ESP和WFGD前后4个测点进行烟气痕量元素同时取样，研究了12种痕量元素（Cr、Mn、Co、Ni、Cu、Zn、As、Mo、Cd、Sb、Ba、Pb）的排放特性.结果表明：整个电厂系统、锅炉、SCR、ESP和WFGD中痕量元素的质量平衡率都在可接受范围内，实验结果准确可靠.这12种痕量元素主要分布于ESP飞灰中，相对分布率为69.97%~98.79%.底渣中痕量元素的相对富集指数在0.04~0.51之间，ESP飞灰中痕量元素的相对富集系数在0.3~1.23之间.ESP飞灰中的As、Cd和Pb以及WFGD废水中的Mn、Co和Ni可能会对土壤和地下水产生污染，需要引起关注.12种痕量元素向大气中的排放浓度位于0.02~12.57μg/m³之间，排放因子位于的0.01~2.13g/10¹²J之间，Ni、As、Cd和Pb这4种元素的排放浓度分别达到2.04、0.13、0.02和3.35μg/m³，都远超欧盟空气质量标准中的排放限值，需要加以重视进行限制.

Experimental study on emission characteristics of trace elements in 600MW coal fired power plant

In this study, trace elements in the flue gas at the inlet/outlet of SCR, ESP and WFGD at a 600MW coal-fired power plant were sampled by the USEPA Method 29 simultaneous. The emission of 12 trace elements (Cr, Mn, Co, Ni, Cu, Zn, As, Mo, Cd, Sb, Ba, Pb) was studied. The results showed that the mass balance rates of trace elements of the entire power plant system, boiler, SCR, ESP, and WFGD were within an acceptable range, which indicates experimental results are accurate and reliable. The 12 trace elements were mainly distributed in the ESP fly ash with relative distribution rates of 69.97%~98.79%. The relative enrichment indexed of trace elements in the bottom slag were between 0.04 and 0.51 and that in the ESP fly ash were between 0.3 and 1.23. As, Cd and Pb in ESP fly ash and Mn, Co and Ni in WFGD wastewater may pollute soil and groundwater, which need to give enough attention. The emission concentration of 12 trace elements into the atmosphere was 0.02~12.57μg/m³ with the emission factor of 0.01~2.13g/10¹²J. The emission concentration of Ni, As, Cd and Pb reached 2.04, 0.13, 0.02 and 3.35μg/m³, respectively, which far exceed the emission limits of the European Union air quality standards and should be restricted.