Wang Lin, Cheng Wen-Chieh, Xue Zhong-Fei, Xie Yi-Xin, Lv Xin-Jiang
School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering (XAUAT), Xi'an, 710055, China.
J Environ Manage. 2023 Dec 15;348:119348. doi: 10.1016/j.jenvman.2023.119348. Epub 2023 Oct 21.
Although the electrokinetic (EK) remediation has drawn great attention because of its good maneuverability, the focusing phenomenon near the cathode and low removal efficiency remain to be addressed. In this study, a novel EK reactor was proposed to remediate Cu and Pb contaminated loess where a biological permeable reactive barrier (bio-PRB) was deployed to the middle of the EK reactor. For comparison, three test configurations, namely, CG, TG-1, and TG-2, were available. CG considered the multiple enzyme-induced carbonate precipitation (EICP) treatments, while TG-1 considered both the multiple EICP treatments and pH regulation. TG-2 further considered NH recovery based on TG-1. CG not only improved Cu and Pb removals by the bio-PRB but also depressed the focusing phenomenon. TG-1 causes more Cu and Pb to migrate toward the bio-PRB and aggravates Cu and Pb removals by the bio-PRB, depressing the focusing phenomenon. TG-2 depressed the focusing phenomenon the most because Cu and Pb can combine with not only CO but PO. The removal efficiency of Cu and Pb is 34% and 36%, respectively. A NH recovery of about 100% is attained.
尽管电动修复（EK）因其良好的可操作性而备受关注，但其阴极附近的聚焦现象和较低的去除效率仍有待解决。在本研究中，提出了一种新型的EK反应器来修复铜和铅污染的黄土，其中在EK反应器的中部设置了生物可渗透反应屏障（bio-PRB）。为作比较，提供了三种测试配置，即CG、TG-1和TG-2。CG考虑了多种酶诱导碳酸盐沉淀（EICP）处理，而TG-1既考虑了多种EICP处理又考虑了pH调节。TG-2在TG-1的基础上进一步考虑了氮回收。CG不仅提高了bio-PRB对铜和铅的去除率，还抑制了聚焦现象。TG-1使更多的铜和铅向bio-PRB迁移，并加剧了bio-PRB对铜和铅的去除，抑制了聚焦现象。TG-2对聚焦现象的抑制作用最大，因为铜和铅不仅能与碳酸根结合，还能与磷酸根结合。铜和铅的去除效率分别为34%和36%。实现了约100%的氮回收。
