Numerical Modeling for Acidification of Soil by Electrokinetic Processing
Electrokinetic soil remediation by electroosmosis and ionic migration is restricted to soluble substances.At a higher pH,the soil particles sorb more heavy metals,such as cadmium,than at a lower pH and the precipitation reactions of heavy metals are promoted.Both mechanisms make heavy metals immobile,rendering clean up more difficult and electrokinetic extraction inefficient.Therefore,the acidification of soils is very important to increase the clean up efficiencies of heavy metals,such as cadmium by electrokinetic method from contaminated soils.In the present study,acidification of soils and cadmium transport are predicted with a numerical method in which electrical flow is coupled with hydraulic flow,and the sorption process in the soils is induced in the model.The effects of some factors such as electrode configuration,electric field strength and electrode spacing for saturated soils are investigated using this numerical model.The results obtained this study are summarized as follows:The two-dimensional electrode configurations containing cathode surrounded by three or more anodes rapidly acidify the soils and remove cadmium from soils compared with one-dimensional electrode configuration.However,two-dimensional electrode configurations develop spots of inactive electric field between cathodes.A larger electrode spacing increases the processing time required,and it was also found that a larger electric field strength reduced the processing time required.
Numerical modeling Acidification of soils Soil remediation Electrokinetic processing
M.Niinae K.Aoki
Department of Urban and Environmental Engineering,Kyoto University,Japan
国际会议
XXIV International Mineral Processing Congress(第24届国际矿物加工大会)
北京
英文
4073-4081
2008-09-24（万方平台首次上网日期，不代表论文的发表时间）