燃煤电厂痕量元素协同脱除及排放

为了研究痕量元素在电厂排放物中的分布、富集以及常规污染物净化设施（脱硝装置（SCR）、电除尘器（ESP）、湿法烟气脱硫装置（WFGD）、湿式电除尘器（WESP））对痕量元素的协同脱除效果，采用美国环境保护署（USEPA）方法29，对某350 MW典型燃煤机组烟气及各污染物净化设施排放物中11种痕量元素（Be、Cr、Mn、Co、Ni、As、Se、Cd、Sb、Pb、Hg）浓度进行了测试。结果表明，煤粉燃烧后释放的痕量元素主要富集在ESP飞灰和石膏中，而在炉渣和烟囱入口烟气中分布较少；富集在ESP飞灰和石膏中的痕量元素分别占痕量元素排放总量的54.51%~97.58%和1.61%～38.08%；常规污染物净化设施对烟气中痕量元素的综合脱除效率为91.98%~99.98%，烟囱入口排放的痕量元素质量浓度为0.02~9.23 μg/m³，其中Mn、As、Se、Pb等元素质量浓度高于美国EPA颁布的火电厂环保标准中新建燃煤机组排放限值。

Research on Co-removal and Emission of Trace Elements in the Coal-Fired Power Plant

In order to study the distribution and enrichment of the trace elements in the emissions from power plants and the synergistic removal of the trace elements from conventional pollutant purification facilities(SCR, ESP, WFGD, WESP), the concentration of the trace elements (Be, Cr, Mn, Co, Ni, As, Se, Cd, Sb, Pb, Hg) in the emissions of smoke and air pollutant control devices are tested by using US EPA Method 29 in a 350 MW coal-fired power unit. The results show that the trace elements that are mainly distributed in the fly ash and the gypsum takes 54.51%~97.58% and 1.61%~38.08% respectively of the total amount of emitted trace elements, while much less are distributed in the bottom ash and the chimney inlet flue gas. The overall removal rate through air pollutant control devices is 91.98%~99.98%. The concentration of trace elements in the stack is 0.02~9.23 μg/m³, and the concentration values of Mn, As, Se, Pb concentrations are much higher than the ones that are required for the new coal-fired unit trace elements emission quality standards issued by EPA.