Effectiveness and impact factors of passive convergence-permeable reactive barrier (PC-PRB): Insights from tracer simulation study

• Published in: Journal of environmental management Vol. 370; p. 122941
• Main Authors: Zheng, Kaixuan, Li, Yihao, Tao, Shiyang, Ding, Jie, Li, Fuli, Peng, Xiangqin, Ou, Jieyong, Chen, Yanzhi, Lei, Lei, Wang, Wei, Wang, Hongtao, Liu, Na, Wen, Yong, Liu, Xiaowen
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.11.2024
• Subjects: Image analysis; Impact factors analysis; Passive convergence; Permeable reactive barrier; Pollutant migration interception; Tracer simulation; Image analysis; Permeable reactive barrier; Pollutant migration interception; Tracer simulation; Passive convergence; Impact factors analysis
• DOI: 10.1016/j.jenvman.2024.122941
• ISSN: 0301-4797; 1095-8630

Passive convergence-permeable reactive barrier (PC-PRB) represents a green and sustainable technology for in-situ remediation of contaminated groundwater. A laboratory-scale PC-PRB tracer simulation system was established to quantify its contaminant plume capture performance using image analysis method. Results indicate that PC-PRB captures the plume 65% wider than C-PRB, which means that fewer PRB sizes and materials volume would be necessary to treat an equivalent contaminated plume. This improvement is due to a significant drawdown within the PC-PRB's passive well, known as the passive hydraulic decompression-convergent flow effect. We further evaluated the effects of water pipe length, hydraulic gradient, and media particle size on PC-PRB's plume capture performance. Results indicate that an increased water pipe length enhances the PC-PRB's plume capture capacity due to greater well drawdown. PC-PRB not only captures the plume but also acts as a hydraulic barrier. The retardation effect of PC-PRB on plume migration increases with water pipe length. Conversely, both hydraulic gradient and media particle size impact the plume capture capacity of PC-PRB by modifying groundwater flow velocity and pollutant dispersion. An increase in either hydraulic gradient or media particle size decreases the plume capture performance of PC-PRB. Therefore, PC-PRB technology may be more effective in contaminated sites characterized by low hydraulic gradients and permeability. Overall, PC-PRB demonstrates significant effectiveness in enhancing plume capture performance, which can notably reduce remediation costs and environmental footprint, broadening its application scope. •A laboratory-scale PC-PRB tracer simulation system was established.•PC-PRB plume capture performance was quantitatively evaluated using image analysis.•PC-PRB's contaminant plume capture width is 65% wider than C-PRB's.•Increasing water pipe length enhances plume capture capacity for PC-PRB.•Larger hydraulic gradient or media particle size reduces PC-PRB capture capacity.