摘要
采用化学热力平衡分析方法研究了在煤燃烧和气化过程中产生的烟气里痕量元素汞的形态及分布 .在一个大气压下 ,40 0K— 2 0 0 0K温度范围里 ,研究了汞 -煤系统和汞 -煤 -氯系统中汞在还原性气氛和氧化性气氛的烟气中的化学形态和分布 ,着重探讨了煤中的氯元素对汞在烟气中的形态和分布的影响 .化学热力平衡分析结果表明 ,在煤燃烧和气化的最高温度区域里 ,单质汞是汞的主要形式 ,少量的氯元素可以大大地增强汞元素的蒸发 ;在气化的还原性气氛烟气中 ,汞的主要形式是单质汞 ,在氧化性气氛的燃煤烟气中随着在烟气中温度的降低 ,单质汞将发生化学反应而生成氯化汞 ;烟气中氯元素的含量越大 。
Using chemical thermal equilibrium analysis the speciation of mercury in flue gases during coal combustion and gasification was studied Under standard atmosphere and temperature of 400K—2000K and in Hg Coal system and Hg Coal Cl system,the speciation of mercury was studied in reducing atmosphere and oxidizing atmosphere, especially the effect of chlorine on the speciation of Hg was discussed.The results showed that in the high temperature zone of coal combustion and gasification,elemental mercury is in thermal stable form, chlorine can greatly improve the evaporation of mercury In the reducing atmosphere,the elemental Hg is the main form, while in the oxidizing atmosphere, at low temperature zone, the elemental Hg will react with other components in the flue gases to form HgCl 2 The greater the content of Cl in flue gases, the wider temperature zone of the main form of mercury HgCl 2 is obtained
出处
《环境科学学报》
CAS
CSCD
北大核心
2001年第1期69-73,共5页
Acta Scientiae Circumstantiae
基金
国家重点基础研究专项资金资助(项目编号:G1999022212)
国家自然科学基金资助项目(批准号:59876013)。
关键词
煤
汞
形态
coal
mercury
speciation
