湿式烟气脱硫系统同时脱汞研究  

Study on simultaneous removal of SO_2 and Hg in wet flue gas desulfurization

作　　者：赵毅[1] 陈周燕[1] 汪黎东[1] 张受卫[2] 

机构地区：[1]华北电力大学环境科学与工程学院,保定071003 [2]山东电力工程咨询院,济南250013

出　　处：《环境工程学报》2008年第1期64-69,共6页Chinese Journal of Environmental Engineering

摘　　要：研究表明,湿法烟气脱硫装置(WFGD)可去除烟气中绝大部分Hg2+,但对单质汞的吸收效果不明显,因此研究提高湿法烟气脱硫系统中单质汞的氧化率的方法对控制汞的排放具有重要意义。综述了WFGD及在此系统中各种添加剂的脱汞性能,认为在添加剂中,气态的臭氧、液态的次氯酸和氯化钠稀溶液、黄磷乳浊液、氢硫化钠溶液及EDTA的汞去除效果较好,且不会被SO2大量消耗,可在WFGD系统实现同时脱硫脱汞;而气态的氯气,液态的K2S2O8溶液虽然也有较好的汞去除效果,但因易被SO2或亚硫酸盐溶液消耗,当在WFGD系统中用其氧化单质汞时,需要对脱硫塔进行分层或其他改造,使烟气中的SO2被吸收后再控制汞,提高经济性。It was indicated that wet flue gas desulfurization （WFGD） system could remove a high percentage of mercury （Ⅱ） from the flue gas but was ineffective at removing Hg^0. So it is significant to study the method of increasing mercury oxidation rate to remove total mercury in WFGD. An overview of the mercury removal effectives of several additives in WFGD was presented. In these additives, ozone, chloric acid and sodium chlorate （NOXSORB^TM） dilute solution, yellow phosphorus emulsion, sodium bisulfide solution and ethylenediaminetetracetic acid （EDTA） which would not be consumed largely by SO2 were believed to have certain effects. Thus, simultaneous removal of mercury and SO2 in WFGD system could be achieved. Additives such as Cl2 , and potassium persulfate solution （K2S2O8） also had certain effects but they were easily consumed by SO2 and sulfite solution, the scrubbing tower should be modified while these additives were used to oxidize the Hg^0 in WFGD in order to reduce the capital and operation cost.

关 键 词：湿式烟气脱硫 同时脱除 汞 

分 类 号：X701.3[环境科学与工程—环境工程]