Constant current vs constant voltage – two types of tests for the experimental application of electrochemical technology for organic polluted soils

Cleaning up all historically-contaminated sites, commonly of industrial origin, to background concentrations or levels suitable to all uses often is not viewed as technically or economically feasible. As a result, clean-up strategies increasing are designed to employ sustainable, long-term solutions, often using a risk-based approach to land management aimed at achieving “fitness for use” appropriate to the location. In the absence of specific EU legislation to address the cleanup of contaminated soil, Member States apply the “polluter pays” principle to varying degrees in clean-up programs. The aim of the experimental research was to assess the feasibility of two types of electrochemical treatment, one treatment that is based on the application of a constant voltage and other treatment that is based on the application of a constant current. For this purpose several bench scale laboratory tests were performed. The results obtained during the research showed that the electrochemical treatment can reach a high efficiency up to 80% by applying the electrochemical treatment at a constant voltage, depending on the treatment period. Also it was demonstrated that by using the method of changing potential it can be obtained also uniformity along the soil sample.