添加剂对抑制模拟脱硫浆液中汞再释放的影响  

Effects of additives on stabilization and inhibition of mercury re-emission in simulated wet gas desulphurization slurry

作　　者：毛琳 张志越 孙佳兴 祁东旭 陈逸鹏 杨宏旻[1] MAO Lin;ZHANG Zhi-yue;SUN Jia-xing;QI Dong-xu;CHEN Yi-peng;YANG Hong-min(School of Energy and Mechanical Engineering,Nanjing Normal University,Nanjing 210042,China)

机构地区：[1]南京师范大学能源与机械工程学院,江苏南京210042

出　　处：《燃料化学学报》2018年第10期1265-1271,共7页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金(51676101);江苏省自然科学基金(BK20161558)资助~~

摘　　要：针对湿法脱硫系统中汞还原再释放问题,选用Na_2S、2,4,6-三硫醇基钠代三嗪(TMT-18)、二硫代氨基甲酸盐类(DTCR-2)和Fenton试剂作为添加剂,探究其对脱硫浆液中汞再释放现象的影响。结果表明,四种添加剂均能有效抑制该现象的发生。1.0倍化学计量比的Na_2S足够与浆液中Hg^(2+)结合成HgS,从而将还原再释放的汞含量降低至5.27%。重金属捕集剂TMT-18和DTCR-2的最佳投加量分别为3.0倍和1.0倍化学计量比,通过与Hg^(2+)结合形成有机螯合物将浆液中的汞固定在螯合产物中,从而降低Hg^(2+)的还原,再释放的汞含量分别降低至5.09%和4.62%。具有强氧化性的Fenton试剂,当H_2O_2浓度为0.3 mol/L,[Fe^(2+)]/[H_2O_2]=1∶8时,浆液中仅有2.31%的汞被还原再释放。四种添加剂中Fenton对于浆液中汞还原再释放的抑制效果最好。In view of the problem of mercury re-emission in wet flue gas desulfurization system,Na 2S,2,4,6-trimercaptotiazine trisodium(TMT-18),sodium dithiocarbamate(DTCR-2)and Fenton reagents were added into the desulfurization slurry to study their effects on mercury re-emission.The results show that the 4 additives could effectively inhibit the mercury re-emission.1.0 time stoichiometric ratio of Na 2S is enough to combine with Hg 2+in the slurry into HgS.Thereby the ratio of mercury re-emission reduces to 5.27%.The optimum dosage of heavy metal chelating agents TMT-18 and DTCR-2 are 3.0 and 1.0 time stoichiometric ratio.They combine with Hg 2+to form organic chelate mercury and then fix it.So the ratio of mercury re-emission reduces to 5.09%and 4.62%,respectively.After adding Fenton reagent with a strong oxidizing into the slurry,the ratio of reduced mercury reduces to only 2.31%when H 2O 2 concentration is 0.3 mol/L and the ratio of[Fe 2+]/[H 2O 2]is 1∶8.Fenton reagent has the best effect on mercury re-emission in the simulated wet gas desulphurization slurry among 4 additives.

关 键 词：Na2S TMT-18 DTCR-2 FENTON试剂 汞再释放 湿法脱硫 

分 类 号：X703.1[环境科学与工程—环境工程]