燃煤电厂烟气汞控制技术在美国的研究进展

Review of Mercury Control Technologies for Power Plant Flue Gas in United States

汞污染严重威胁人类的健康。燃煤电厂烟气中的汞排放约占人类活动总排放量的1/3。主要介绍了美国在燃煤电厂烟气中汞控制领域的研究进展,包括烟气中汞的形态,目前气体污染控制设备的作用,现有的大气污染控制技术对汞去除效率的影响、各技术的优缺点。提出燃烧前去除煤中汞的方法可以将污染物汞转移到了煤洗废物中;吸附剂注入法可以有效吸附烟气中的汞,但成本较高,烟气中产生的飞灰被吸附剂及汞污染;涂层法克服了吸附剂注入法的缺点。该方法目前处于研究和中试阶段,不久将实现工业化。

Mercury pollution can seriously influence health of human beings. Mercury emission from power plant flue gas consists of around 1/3 of anthropogenic activities. Research progresses in this field in United States were discussed, including mercury state in flue gas, role of current air pollution control devices, state-of-art of mercury control technologies and their advantages and disadvantages. Part of mercury in coal could be washed out to waste effluents by coal cleaning. Mercury could be effectively removed from flue gas by sorbent injection, However, fly ash generated by coal burning is contaminated by adsorbent and mercury, and adsorbent used in sorbent injection is quite expensive. In stead of inject adsorbents into flue gas, coat the fabric filter with carbonaceous and/or sulfur containing materials can solve the problems of sorbent injection technology. This novel technology is still under pilot study and will be commercialized in the future.