Process-based modeling of electrokinetic-enhanced bioremediation of chlorinated ethenes

JOURNAL OF HAZARDOUS MATERIALS

卷:397

Article

Sprocati, Riccardo¹  Flyvbjerg, John²  Tuxen, Nina²  Rolle, Massimo¹ 

[1] Tech Univ Denmark, Dept Environm Engn, Bygningstorvet,Bldg 115, DK-2800 Lyngby, Denmark

[2] Capital Reg Denmark, Ctr Reg Dev, Kongens Vaenge 2, DK-3400 Hillerod, Denmark

关键词: Electrokinetic remediation;    Chlorinated solvents;    Reductive dehalogenation;    Electromigration and electroosmosis;    Reactive transport modeling;   

DOI  :  10.1016/j.jhazmat.2020.122787

来源: Elsevier

【 摘 要 】

This study presents a process-based modeling analysis of electrokinetic-enhanced bioremediation (EK-Bio) to illuminate the complex interactions between physical, electrostatic and biogeochemical processes occurring during the application of this remediation technique. The features of the proposed model include: (i) multidimensional electrokinetic transport in saturated porous media by electromigration and electroosmosis, (ii) charge interactions, (iii) degradation kinetics, (iv) microbial populations dynamics of indigenous and specialized exogenous degraders, (v) mass transfer limitations, and (vi) geochemical reactions. A scenario modeling investigation is presented, which was inspired by an EK-Bio pilot application conducted in a clayey aquitard at the Skuldelev site (Denmark) contaminated by chlorinated ethenes. Lactate and specialized degraders are delivered under conservative and reactive transport conditions. In the considered setup, transport of lactate using electrokinetics results in more than fourfold increase in the distribution efficiency with respect to a diffusion-only scenario. Moreover, EK transport by electromigration and electroosmosis yields fluxes at least two orders of magnitude larger than diffusive fluxes. Quantitative metrics are also defined and used to assess the amendment distribution and the enhanced contaminant biodegradation in the different conservative and reactive transport scenarios.

【 授权许可】

Free