减压汇流式PRB渗流调控机制研究  

The seepage regulation mechanism of passive convergence-permeable reactive barrier

作　　者：郑凯旋 陶诗阳 丁洁 陈涤 谭旖琦 雷蕾 陈岩贽 王炜 温勇 彭香琴 王洪涛[2] ZHENG Kai-xuan;TAO Shi-yang;DING Jie;CHEN Di;TAN Yi-qi;LEI Lei;CHEN Yan-zhi;WANG Wei;WEN Yong;PENG Xiang-qin;WANG Hong-tao(State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment,South China Institute of Environmental Science,Ministry of Ecological Environment,Guangzhou 510655,China;School of Environment,Tsinghua University,Beijing 100084,China)

机构地区：[1]生态环境部华南环境科学研究所,国家环境保护环境污染健康风险评价重点实验室,广东广州510655 [2]清华大学环境学院,北京100084

出　　处：《中国环境科学》2024年第11期6210-6220,共11页China Environmental Science

基　　金：国家重点研发计划项目(2018YFC1802300);中央级公益性科研院所基本科研业务专项(PM-zx703-202406-192)。

摘　　要：减压汇流式PRB(Passive convergence-permeable reactive barrier,PC-PRB)是一种新型可持续的地下水原位修复技术.为评估PC-PRB水力捕集性能并揭示其渗流调控机制,本文开发了质点示踪算法精度高和数值解稳定性强的渗流模拟软件PRB-Flow.结果表明,在给定模拟条件下,与连续式PRB(Continuous permeable reactive barrier,C-PRB)相比,PC-PRB平面和剖面捕集流量分别提升约为47%和90%.敏感性分析表明,导水管长度L_(p)、减压井横向范围TD_(w)和减压井深度H_(w)是影响PC-PRB水力性能的关键参数.L_(p)与PC-PRB水力捕集性能之间存在显著的正相关关系(P<0.01).增加TD_(w)和H_(w)均可提升PC-PRB水力捕集能力,但影响程度不及L_(p).导流管的引流减压作用使得减压井内产生降深,促使井周围地下水在水头差的驱动下向井内汇聚,从而显著提升了PC-PRB的水力捕集性能.此外,PC-PRB可有效解决C-PRB因流速不均而产生的局部击穿问题.Passive convergence-permeable reactive barrier(PC-PRB)is a novel and sustainable in-situ remediation technology for contaminated groundwater.To evaluate the hydraulic capture performance of PC-PRB and reveal its seepage regulation mechanism,we developed a PRB-Flow simulation software with high accuracy of particle tracing algorithm and strong numerical solution stability.Under the specified simulation conditions,the PC-PRB exhibited an approximately 47%increase in planar capture flow rate and a 90%increase in sectional capture flow rate compared to the continuous permeable reactive barrier(C-PRB).Sensitivity analysis showed that the water pipe length L_(p),the horizontal range of the passive well TD_(w)and the passive well depth H_(w)were the key parameters affecting the hydraulic performance of PC-PRB.There was a significant positive correlation between L_(p)and the hydraulic capture performance of PC-PRB(P<0.01).Increasing TD_(w)and H_(w)can enhance the hydraulic capture capacity of PC-PRB,but the influence degree was not as significant as L_(p).The drainage and depressurization effect of the water pipe makes the head drop in the passive well,which drives the surrounding groundwater to converge into the well,thus significantly improving the hydraulic capture performance of PC-PRB.PC-PRB can effectively solve the local breakthrough problem of C-PRB caused by uneven flow velocity.

关 键 词：渗透性反应墙 减压汇流 水力捕集 渗流调控 敏感性分析 

分 类 号：X523[环境科学与工程—环境工程]