Electrochemical technologies for the regeneration of urban wastewaters

Nowadays, the lack of water resources in many countries promotes the research in the finding of new sources. Regeneration is one of the best choices, and electrochemical technology can be an interesting alternative to the existing technologies. This work reports a preliminary study of the usefulness of conductive-diamond electrochemical oxidation (CDEO) and electrocoagulation in the regeneration of three different actual effluents. Results show that electrocoagulation can easily remove ionic phosphorus and COD associated to colloids. It also has a buffering effect on the pH of the effluent. CDEO can disinfect the effluents and simultaneously it can completely remove the COD of the actual effluents, including persistent organic pollutants (POPs). To check this point electrolysis of solutions of different concentrations of sulfamethoxazole were tested. Energy consumptions lower than 4.5 kWh m⁻³ can be enough to disinfect and remove typical POPs organic loads. This study shows that both electrochemical processes can be robust alternatives to the existing regeneration technologies.