LAB-SCALE MONITORING OF ELECTROKINETIC REMEDIATION OF CONTAMINATED SEDIMENTS

The management of dredged sediment is commonly recognized as a complex procedure in industrialized countries, where sediments are often contaminated by metals and organic contaminants due to the presence of a number of point and diffuse contamination sources. Due to the huge amounts of sediments to be dredged due for either maintenance or environmental dredging purposes, management options different from landfilling are claimed. Among the available treatment options, Electrokinetic Remediation (EKR) appears to be particularly suitable due to a number of potential advantages, including the capability of treating finely graded and low-permeability matrices such as sediments, and the ability of removing organic and inorganic contaminants. In order to improve the remediation process, enhancing agents such acids, chelating agents, surfactants can be added in the electrode compartments. However, due to the complexity of both the sediment matrix and the contaminants nature, despite the interest demonstrated by the scientific sector in EK, the uncertainties in process yields and control still hinder its full-scale application. This work was aimed at studying EKR for metal removal from contaminated sediment samples from three Italian harbors. The lab-scale EKR tests were performed using different types of acids, namely acetic, nitric and hydrochloric acid.