摘要
低温热解技术是修复汞污染土壤的有效方法之一,对高浓度汞污染土壤除汞效率可达90%以上,但对甲基汞(MeHg)的去除效果目前还缺少研究。本研究以化工汞污染和汞矿污染类型土壤为研究对象,研究低温热解修复前后土壤性质、总汞(THg)、汞的形态分布和MeHg等的变化及其影响情况。研究表明,化工污染区和汞矿污染区土壤MeHg去除率分别在99.65%和90.96%左右,THg去除率分别在94.35%和95.40%左右;高浓度汞污染土壤中汞的形态分布以残渣态汞和有机结合态汞为主,经低温热解修复后化工污染区和汞矿污染区土壤中有机结合态汞分别降低96.62%和92.05%,残渣态汞分别降低93.08%和96.79%;有机质含量高的稻田土壤具有较强的汞甲基化能力,其土壤MeHg含量化工污染区(56.47±2.65μg/kg)>汞矿污染区(3.98±0.42μg/kg)。
The low-temperature pyrolysis technique,which can remove more than 90%of mercury from highly mercury contaminated soils,is one of the effective methods to remediate mercury contaminated soils.However,few research was focused on the removal of MeHg.In this study,contaminated soils were collected from areas of chemical plants and mines,the low-temperature pyrolysis technique was employed to remediate these contaminated soils,and soil properties,total mercury(THg),morphological distribution of mercury and MeHg in soils before and after remediation were investigated.The results showed that the residual form and the organic were the dominated mercury occurrences in heavily contaminated soils,and that,after remediation of the low-temperature pyrolysis,contents of MeHg and THg were reduced by 99.65%and 94.35%respectively in soils from the chemical plant area and reduced by 90.96%and 95.40%respectively in soils from the mining area,similarly,contents of organic bound and residual bound mercury were reduced by 96.62%and 93.08%respectively in soils from the chemical plant area and by 92.05%and 96.79%respectively in soils from the mining area.In addition,this study found that the paddy soil with high content of organic matter showed the strong ability of mercury methylation and the mean content of MeHg in paddy soils from the chemical plant area was 56.47±2.65μg/kg,which is much higher than that(3.98±0.42μg/kg)in paddy soils from the mining area.
作者
耿雷
瞿丽雅
余志
张军方
郭程程
GENG Lei;QU Liya;YU Zhi;ZHANG Junfang;GUO Chengcheng(College of Resources and Environmental Engineering,Guizhou University,Guiyang 550025,China;Research and Design Institute of Environmental Science of Guizhou Province,Guiyang 550023,China;College of Geographic and Environmental Sciences,Guizhou Normal University,Guiyang 550025,China)
出处
《地球与环境》
CAS
CSCD
北大核心
2019年第5期689-695,共7页
Earth and Environment
基金
国家自然科学基金项目(41463013)
贵州省社发攻关项目(黔科合[2016]支撑2804号)
2016年度贵州省高层次创新型人才培养项目
关键词
低温热解
土壤
总汞
形态分布
甲基汞
low-temperature pyrolysis
soil
total mercury
morphological distribution
methylmercury
