Electrokinetic Soil Remediation Method for Mix Contaminated Soil

The mix contamination presents a particularly difficult task for soil remediation. The objective of research was to find a method to cleanup mixed contaminated clayey soils. Clayey soil, contaminated with lead and nickel (heavy metals) and phenanthrene (PAH), was subjected to simultaneous removal using a multifunctional electrokinetic system. The electrokinetic surfactant supply system was applied to mobilize, transport and remove phenanthrene. A chelation agent (EDTA) was also electrokinetically supplied to mobilize heavy metals. The mixed contaminated clayey soil was subjected to low DC voltage gradient. Conditioning liquids (surfactant and EDTA) were introduced in different periods of time (22 days, 42 days) in order to optimize the most excessive removal of contaminants. The pH, electrical parameters, volume supplied, and volume discharged was monitored continuously during lab experiments. At the end of tests soil and cathalyte were subjected to physico-chemical analysis. Results showed that the optimal average simultaneous removal was 85 % for lead, 84 % for nickel, and 74 % for phenanthrene. The highest local removals achieved for lead, nickel and phenanthrene were 96 %, 95 %, and 84 % respectively. The results of this study can be applied for in-situ remediation of clayey sites contaminated with petroleum products and heavy metals

Keywords:

remediation , electrokinetic , clay , mixed contaminants , heavy metals , phenanthrene , surfactant , EDTA