Electro-bioremediation of contaminated sediment by electrode enhanced capping

Abstract

In-situ capping often eliminates or slows natural degradation of hydrocarbon due to the reducing conditions in the sediments. The purpose of this research was to demonstrate a reactive capping technique, an electrode enhanced cap, to produce favorable conditions for hydrocarbon degradation and evaluate this reactive capping technique for contaminated sediment remediation. Two graphite electrodes were placed horizontally at different layers in a cap and connected to external power of 2 V. Redox potentials increased and pH decreased around the anode. Phenanthrene concentration decreased and PAH degradation genes increased in the vicinity of the anode. Phenanthrene concentrations at 0–1 cm sediment beneath the anode decreased to ~50% of initial concentration over ~70 days, while phenanthrene levels in control reactor kept unchanged. A degradation model of electrode enhanced capping was developed to simulate reaction-diffusion processes, and model results show that a reaction-dominated region was created in the vicinity of the anode. Although the degradation dominated region was thin, transport processes in a sediment cap environment are typically sufficiently slow to allow this layer to serve as a permeable reactive barrier for hydrocarbon decontamination.

[Preprint] An overview of electrokinetic soil flushing and its effect on bioremediation of hydrocarbon contaminated soil

“…The use of solar panels and electrolyte recirculation can reduce operational costs and pH and corrosion changes in the EKSF-Bio electrode. Furthermore, the research on how to make an appropriate and efficient processing designs are needed to make this technology more sustainable (Annamalai et al, 2017;Gill et al, 2015a;Yan and Reible, 2015).…”

“…The limitation of primary energy sources such as coal and grid becomes important to be addressed. Some technologies such as solar panels, wind energy and microbial fuel cells can be used as an alternative energy source (Gill et al, 2014;Hassan et al, 2016b;Habibul et al, 2016;Souza et al, 2016;Yan and Reible, 2015). Habibul et al (2016) stated that microbial fuel cells (MFCs) can efficiently drive sustainable electrokinetic remediation to remove Cd and Pb within 100 days of operation.…”

“…This technology is quite attractive because it is environmentally friendly and can be used in remote locations . Solar panels are known to be more desirable than other alternatives because they produce electricity in nearly zero pollution, low maintenance costs and long time operation (Hassan et al, 2015;Yan and Reible, 2015). Solar panels and winds technology require batteries because in the calm conditions (without wind source) or lack of sunlight (night / cloudy), energy is necessary for electrokinetic process sustainability.…”

Performance of electroremediation in real contaminated sediments using a big cell, periodic voltage and innovative surfactants

“…Electrodes material and configuration [4][5][6][7][8], use of solubilizing agents e.g. chelating agents, surfactants, cyclodextrins, co-solvents as well as granulometry of the soil/sediment sample [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25], control and effect of operating parameters e.g.…”

Combination of pulsed corona discharge plasma and gamma-Al 2 O 3 -supported catalysts for polycyclic aromatic hydrocarbon removal in soil

“…Electrochemical technologies have been developed for soil remediation. Direct oxidation/reduction of soil contaminants at electrodes or induced mobility leads to potential effectiveness of electrokinetic remediation [9,10]. However, the mobility of PAHs is not redox sensitive and PAHs are readily adsorbed by soil particles.…”