摘要
页岩气开采区油基钻井液的使用会导致土壤受到石油类物质污染,探究石油类污染物在土壤中的环境行为对受污染土壤的修复有重要意义。为此,文章选择以涪陵页岩气开采区为研究区域,通过批量平衡试验研究废油基钻井液中石油类物质在土壤中的吸附/解吸特性,并采用动力学模型进行拟合分析;以土柱淋滤法探究不同降水量和污染强度对土壤中石油类污染物纵向迁移特性。研究结果表明,土壤对石油类污染物的吸附能力较强,解吸率低,吸附平衡状态下的土-水分布系数Kd值为51.86 mL/g,准二级动力学模型对吸附和解吸附过程均有很好的拟合效果,R^(2)均大于0.99,表明吸附/解吸速率主要受化学吸附机理的控制。石油类污染物主要分布在土壤的表层(0~18 cm),且随深度的增加呈下降趋势。石油类污染物迁移的深度及迁移量受污染强度、淋滤量等因素的影响,总体上,随着污染强度及淋滤量的增加,石油类污染物在土壤中的迁移量及迁移深度也增加。
The use of oil-based drilling fluids in shale gas exploration areas can cause soil to be contaminated by petroleum.It is significant to explore the environmental behavior of petroleum pollutants in soil for the remediation of petroleum-contaminated soil.Fuling shale gas exploitation area was selected as the research area.The batch equilibrium method was used to study the adsorption/desorption characteristics of petroleum pollutants in the soil,and the kinetic model was used for fitting analysis.And the soil column leaching experiment was used to simulate the vertical migration of petroleum pollutants in the soil under different precipitation and pollution intensities.The research results show that the soil had a strong adsorption capacity and a low desorption rate for petroleum pollutants.The soil-water distribution coefficient value(Kd)in the adsorption equilibrium state was 51.86 mL/g.The adsorption kinetics process and the kinetics desorption process could be interpreted by the pseudo-second-order kinetic model,R^(2)was greater than 0.99,the adsorption/desorption rate was controlled by the chemical adsorption mechanism.Petroleum pollutants were mainly distributed on the surface layer of soil(0~18 cm),and showed a downward trend as the depth increases.The depth and amount of vertical migration of petroleum pollutants were affected by pollution intensity,leaching amount and other factors.In general,the migration amount and the depth of petroleum pollutants in the soil will increase with the increase of the pollution intensity and leaching amount.
作者
杨英还
杨渝红
蒋娇娇
陈柯锦
王里奥
何容
王翔
YANG Yinghuan;YANG Yuhong;JIANG Jiaojiao;CHEN Kejin;WANG Li’ao;HE Rong;WANG Xiang(State Key Laboratory of Coal Mine Disaster Dynamics and Control,Chongqing University,Chongqing 400044,China;College of Environment and Ecology,Chongqing University,Chongqing 400044,China;Chongqing Normal University,Chongqing 401331,China)
出处
《环境科学与技术》
CAS
CSCD
北大核心
2021年第7期100-107,共8页
Environmental Science & Technology
基金
重庆市技术创新与应用示范专项(cstc2018jszx-zdyfxmX0005)
重庆大学研究生科学研究与创新基金项目(CYS20033)
关键词
石油类污染物
吸附
解吸
纵向迁移
页岩气开采
petroleum pollutants
adsorption
desorption
vertical migration
shale gas extraction
