Effect of electrokinetic remediation on indigenous microbial activity and community within diesel contaminated soil

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

“…Basically, EKSF-Bio can be applied directly to contaminated soil by using indigenous microorganisms (Kim et al, 2010;Li et al, 2010;Yuan et al, 2013). Nutrients and electron acceptors are transferred through soil pores by electrokinetic processes so that increasing bioavailability of contaminants.…”

“…Electric current can increase dehydrogenase enzyme activity. This activity is a key parameter to measure biological process in the EKSF-Bio system and demonstrates the oxidation of organic compounds from respiration and metabolic processes (Kim et al, 2010). Microbial cell growth and dehydrogenase activity can be stimulated using oxygen and electrolyte flushing, pH, weak electric current/voltage, nutrients, and the duration of treatment.…”

“…The changes in pH due to electrolysis lead to a decrease in the diversity and number of microorganisms viability. Although weak electric field can cause changes in metabolic activity and bacterial membrane composition, many researchers suggest that substrate utilization and metabolism of microorganisms increase as a result of direct (electron transfer from electrode to bacteria) and indirect stimulation (transfer of electrons) (Kim et al, 2010;Li et al, 2010;Mena et al, 2014). Previous research has revealed that electrokinetic can increase the number of Bacillus and Arthrobacter (Khodadadi et al, 2011;Lear et al, 2004), and increase the metabolism of some soil bacteria and fungi (Lear et al, 2007).…”

A Review Article: Electrokinetic Bioremediation Current Knowledge and New Prospects

“…The effect of fixed applied electric current on different intensities of bacteria suspended on liquid and soil slurry was investigated [50]. It was found that electric current had a detrimental effect on low cell densities, however, high cell densities survived despite the applied electric field intensities and the controlled current environment [72]. The use of electrokinetic bioremediation to remove pentadecane from a kaolinite soil showed that the optimum pollutant removal was achieved using an intermediate electric current density of 0.63 mA/cm 2 compared with the higher and lower current densities of 3.13 and 1.88 mA/cm 2 , respectively [72].…”

“…It was found that electric current had a detrimental effect on low cell densities, however, high cell densities survived despite the applied electric field intensities and the controlled current environment [72]. The use of electrokinetic bioremediation to remove pentadecane from a kaolinite soil showed that the optimum pollutant removal was achieved using an intermediate electric current density of 0.63 mA/cm 2 compared with the higher and lower current densities of 3.13 and 1.88 mA/cm 2 , respectively [72]. Another study showed that using optimum electric field in electrokinetic bioremediation not only removes pollutants but also retains the most microorganisms [73].…”