Electrokinetic extraction of surfactants and heavy metals from sewage sludge

Waste management represents a quite serious problem involving aspects of remediation technologies and potential re-utilization in different fields of human activities. Of course, wastes generated in industrial activities deserve more attention because of the nature and amount of xenobiotic components, often difficult to be eliminated. However, also ordinary wastes of urban origin are drawing more and more attention, depending on the concentration of noxious substances like surfactants and some heavy metal, which may eventually require expensive disposal. In the present paper, a research has been carried out on the application of electrokinetic treatments for the abatement of the above xenobiotic components from sewage sludge generated in urban wastewater treatment plants. Experiments were carried out on a laboratory scale, in a 250 mm × 50 mm × 100 mm cell, using 250–300 g of sludge for each test and current densities between 2.4 and 5.7 mA cm−2. As a general result, quite significant abatements of heavy-metal ions and surfactants were achieved, with relatively low energy consumption.