利用改性钒钛钢渣和飞灰吸附模拟烟气中的Hg^0  

Hg^0 Removal from Simulated Flue Gas with Modified VTS and Fly Ash as Adsorbents

作　　者：石应杰[1,2] 邓双[2] 杨丽[1] 张辰[2] 曹晴[2] 张凡[2] 王红梅[2] 

机构地区：[1]中国矿业大学(北京)化学环境工程学院,北京100083 [2]中国环境科学研究院,北京100012

出　　处：《环境科学研究》2015年第12期1895-1901,共7页Research of Environmental Sciences

基　　金：国家高技术研究发展计划(863)项目(2013AA065001);国家环境保护公益性行业科研专项(201509012,201309018)

摘　　要：固体废弃物钒钛钢渣（VTS）、飞灰（FA）含有Fe、V、Ti等可促进Hg^0氧化吸附的过渡金属氧化物,为提高VTS吸附Hg^0性能、改性FA的抗硫特性,利用蒸汽活化、浸渍Fe Cl3方法改性FA/VTS、FA/CaO,在固定吸附床上研究了不同改性方法、反应温度（T）、烟气ρ（SO2）和ρ（HCl）对η（吸Hg^0效率）的影响.结果表明：蒸汽活化对提高η的作用有限.经浸渍Fe Cl3方法改性的FA/VTS,其η显著提高,在200℃下,吸附20 min时可达93%,吸附10 h后的Q（吸附容量）为0.42 mg/g;而浸渍Fe Cl3方法改性的FA/Ca O,其η随温度呈先升后降趋势,在120℃、吸附20 min时达到最高（74%）.SO2抑制Hg^0的吸附,但FA/VTS的抗硫性能较FA/Ca O有显著提高,具有低温抗硫吸附Hg^0的潜势,可能与VTS中Ti的质量分数高有关.HCl可促进Hg^0的吸附,在ρ（HCl）为30 mg/m^3条件下,浸渍Fe Cl3方法改性的FA/VTS吸附2 h的η在90%以上.研究表明,经Fe Cl3浸渍改性的FA/VTS是较好的Hg^0吸附剂,具有实际应用的潜势.As solid wastes,vanadium titanium steel slag（ VTS） and fly ash（ FA） contain transition metal oxides,such as Fe,V and Ti,which can promote the adsorption of Hg^0. To improve the ability of VTS to adsorb Hg^0 and modify FA to resist sulfur,the methods of steam activation and Fe Cl3 impregnation were applied to modify FA/VTS and FA/Ca O. A fixed bed was used to analyze the impacts by different modification methods under different conditions,such as reaction temperature,SO2 and HCl concentrations,on Hg^0 adsorption.The results showed that the adsorption efficiency of FA/VTS modified by steam activation on Hg^0 showed limited improvement. The adsorption efficiency of FA/VTS modified by Fe Cl3 impregnation improved significantly. When the temperature was lower than 200 ℃,the adsorption efficiency reached 93% after 20 min adsorption. The adsorption capability was 0. 42 mg/g after 10 h adsorption. For FA/Ca O adsorbent by Fe Cl3 impregnation,the adsorption efficiency increased first,then decreased,reaching 74% after 20 min adsorption at 120℃. SO2 inhibited the adsorption of Hg^0. Comparing the two modified adsorbents,the sulfur resistant properties of FA/VTS were improved greater than those of FA/Ca O. FA/VTS had a sulfur resistant potential to absorb Hg^0 at low temperatures; it might be associated with the high content of Ti in VTS. HCl in flue gas could promote the absorbtion of Hg^0. The Hg^0 absorbtion efficiency of FA/VTS modified by Fe Cl3 impregnation was higher than 90% after 2 h adsorption,when 30 mg/m^3HCl was added to the flue. FA/VTS modified by Fe Cl3 impregnation has the potential in practice to achieve sulfur resistance and Hg^0 adsorption at a low temperature.

关 键 词：钒钛钢渣 飞灰 元素汞 氧化钙 吸附 

分 类 号：X701[环境科学与工程—环境工程]