Treatment of landfill leachate nanofiltration concentrate after ultrafiltration by electrochemically assisted heat activation of peroxydisulfate

摘要

An electrochemical assistance (electrochemical/peroxydisulfate/Fe3+) was introduced into a heat-activated peroxydisulfate process to deal with a landfill leachate nanofiltration concentrate after ultrafiltration. The introduction of electrochemical assistance greatly improved the efficiency of heat activation on the target solution treatment. The energy consumption was 91.9 kWh/kgCOD (with a COD removal of 87%) and 189.5 kWh/kgCOD (with a COD removal of 66%) with and without electrochemical assistance, respectively. The acute toxicity for V. Q67 of the target solution was completely eliminated by the electrochemically assisted heat activation process, while it was barely eliminated by heat activation alone. A COD residue of about 172 mg/L and a significant increase on biodegradability (BOD5/COD ratio from nearly zero to 0.46) could be obtained in the effluent, suggesting that the electrochemically assisted heat-activated peroxydisulfate process might be an alternative to deal with this kind of concentrate and it would be friendly to the following biological treatment.