Improving the Electrokinetic Remediation of Nickel-, Cadmium-, and Lead-contaminated Sediment

Abstract

In this work, the simultaneous application of bipolar electrodes and a longer cathodic compartment length without agents addition was used as an enhanced electrokinetic treatment of Ni-, Cd-, and Pb-contaminated sediment. Conventional and enhanced treatments were investigated and their efficacy assessed by comparing the residual metals content in the sediment with values given by Dutch standards. After conventional treatment removals of 20%, 19%, and 31% for Ni, Cd, and Pb were achieved, whereas the enhanced treatment achieved removal efficacies of 36% for Ni, 42% for Cd, and 43% for Pb. Results indicate that the simultaneous application of the techniques mentioned is effective for removing Ni and Pb whereas Cd was not removed to the desired level.Here we show that the addition of chemicals is not necessary to increase the efficacies of electrokinetic sediment treatments, so the simultaneous application of the techniques mentioned can be described as environmentally friendly.

Screening of variable importance for optimizing electrodialytic remediation of heavy metals from polluted harbour sediments

“…Several EKR and EDR studies of polluted sediments have shown limited removal of targeted heavy metals applying the traditional stationary set-up with removal efficiencies generally below 20% with a few exceptions of up to 40% [12,[19][20][21][22].…”

Remediation of clay soil contaminated with lead nitrate using washing-enhanced electrokinetic technique

“…Increasing the mobility of soil solids due to the presence of ions causes rising of the electrical current produced during treatment process. The migration of these ions towards the electrodes during the treatment reduces the electric current [9,20,21]. Generally, the values of electrical current reached a peak value because dissolved salts that are connected with dry soil particles increased the quantity of ions in the pore solution [13,20].…”