Electrokinetics enhanced bioremediation

T0236 Electrokinetic Remediation—General T0237 Electrokinetically Enhanced Bioremediation—General... 

T0237 Electrokinetically Enhanced Bioremediation—General T0238 Electrokinetics, Inc., Electrokinetic Soil Cleaning T0239 Electro-Petroleum, Inc., Electrokinetic Treatment... 

Electrokinetically enhanced bioremediation is an in situ process for the treatment of soils and groundwater contaminated with petroleum hydrocarbons and other compounds easily biodegraded under anaerobic conditions. Bench-scale tests have shown that the apphcation of an electric field provides electrokinetic transport of nutrients and biodegrading bacteria to areas of contamination. In addition, microbial growth is enhanced, nitrate transport can be predicted, and beneficial temperature increases can be achieved to areas of contamination. 

Suni S, Mahnen E, Kosonen J, Sflvennomen H, Romantschuk M. (2007). Electrokinetically enhanced bioremediation of creosote-contaminated soil Laboratory and field studies. Journal of Environmental Science and Health Part A 42 277-287. 

The total costs for using the Electrokinetic soil cleaning technology range from 20 to 100/yd of treated media. The vendor estimated that the costs for an electrokineticaUy enhanced bioremediation project would range from 10 to 90/yd. The costs will vary based on the site s specific chemical and hydraulic properties. The unit price for this technology is dependent on ... 

Pool Process electrokinetic remediation (Pool Process) is a patented, commercially available technology for the removal of heavy metals and other ionic contaminants. The technology uses a series of electrodes placed in contaminated media to recover ionic contaminants in situ or ex situ from soils, muds, groundwater, dredgings, and other materials. The Pool Process can also be used to enhance bioremediation of media contaminated with a combination of ionic and nonionic organic contaminants. 

Electrokinetics has been applied to remove nitrate from soil to protect groundwater and to enhance bioremediation of soil contaminated by other pollutants. In this section, nitrate is treated as a pollutant in Section 6.3.3, it is treated as a nutrient. 

Loo WW. (1994). Electrokinetic enhanced passive in situ bioremediation of soil and ground-water containing gasoline, diesel and kerosene. Paper presented at the HAZMACON Conference, March 29-31, San Jose, CA. 

Electrokinetics may conceivably be used in six general ways for hazardous waste site remediation (a) concentration and dewatering of waste sludges (b) extraction of pollutants from soUs, sediments, and groundwater (c) creation of hydraulic flow barriers (d) injection for dehvery of nutrients or electron acceptors to enhance bioremediation (e) injection of grouts or cleanup chemicals or (f) improvement of the effective permeability of a soil mass (Parker, 1992). 

Furthermore electrokinetic effects also can be used to enhance bioremediation. At many contaminated sites for contaminants, nutrients, electron acceptors, and microorganisms, a nonuniform distribution is observed. Transport of compounds predominately occurs in grotmd-water flow direction and only limited transversal mixing takes place. Hence, the availability of nutrients and electron acceptors, e.g., sulfate or nitrate, is often limiting the bioremediation. The... 

Radio frequency heating, 500 Steam stripping, 500 Vacuum extraction, 500 Aeration, 501 Bioremediation, 501 Soil flushing/washing, 502 Surfactant enhancements, 502 Cosolvents, 502 Electrokinetics, 503 Hydraulic and pneumatic fracturing, 503 Treatment walls, 505 Supercritical Water Oxidation, 507 Solid Solution Theory, 202 Solubility products, 48-53 Metal carbonates, 433-434 Metal hydroxides, 429-433 Metal sulfides, 437 Sorption, 167 See Adsorption Specific adsorption, 167 See Chemisorption Stem Layer, 152-154 Sulfate, 261... 

An accelerated desorption and movement of phenol and 2,4-dichlorophenol (2,4-DCP) in unsaturated soils was achieved by using nonuniform electrokinetics (Luo et al, 2005). Electromigration and EOF were the main driving forces, and their roles in the mobilization of phenol and 2,4-DCP varied with soil pFI. In sandy loam, 2,4-DCP moved between 1.0 and 1.5cm/(day V) slower toward the anode than in the kaolin soU, and about 0.5cm/(day V) greater than phenol in the sandy loam (Fig. 10.7). When the sandy loam was adjusted to pH 9.3, the movements of phenol and 2,4-DCP toward the anode were about two and five times faster than those at pH 7.7, respectively. The movement of phenol and 2,4-DCP in soils can be easily controlled by regulating the operational mode of electric field. The nonuniform electric field could enhance the in situ bioremediation process by promoting the mass... 

Gent D, Bricka RM. (2001). Electrokinetic movement of biological amendments through natural soils to enhance in-situ bioremediation. In Bioremediation of Inorganic Compounds (eds. A Leeson, BM Peyton, JL Means, VS Magar). Richland, WA Battelle Press, pp. 241-248. 

Luo Q, Zhang X, Wang H, Qian Y. (2005). The use of non-uniform electrokinetics to enhance in situ bioremediation of phenol-contaminated soil. Journal of Hazardous Materials B121 187-194. 

According to Lohner [4], the potential benefits of electrokinetic and electrochemical processes coupled with bioremediation include enhancement of pollutant bioavaUabUity by means of electrokinetic mobilization, increase of restricted soil bacteria mobility by electrokinetic transport processes, electrokinetic-induced mass transfer and transport of ionic electron acceptors and nutrients, and electrochemical production of limited electron donors (H2) and acceptors (O2). 

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