Array Optimization and Pilot Verification of Electrokinetic-Enhanced Biodechlorination System

Electrokinetic bioremediation (EK-BIO) shows significant promise for organochlorine remediation in low-permeability matrices. However, its in situ application under site-relevant scenarios remains a substantial challenge. This study establishes a comprehensive EK-BIO lab-to-field framework that includes laboratory batch experiments, array optimization, pilot-scale field validation, and life cycle assessment. Primarily, batch and column experiments optimized both the additive dosage strategy and electrode array configuration, favoring a 6-day preinoculation of the niche-preparing culture and a unidirectional one-dimensional electrode setup. Guided by these findings, the 98-day EK-BIO pilot experiment achieved over 90.0% TCE removal, with a 74.0% chloroethylene-to-ethylene conversion efficiency. Microbial community analyses further revealed a notable increase in the relative abundance of putative organohalide-respiring bacteria in the EK-BIO, approximately 25.6% and 34.3% higher than in bioaugmentation and electrokinetic treatments, respectively. Additionally, life cycle assessment results underscored the advantages of EK-BIO over conventional thermal remediation alternatives, with reductions in carbon emissions, energy consumption, and remediation costs. This study validated the feasibility and reliability of EK-BIO technology, supporting its advancement for the in situ remediation of organochlorine-contaminated sites.