摘要
Landfill leachate is a complex effluent and it is difficult to deal with. Electrochemical methods have been considered as a promising alternative technology for treatment of landfill leachate with refractory organic contaminants and heavy metals. Peroxi-coagulation(PC)process with iron anode and modified graphite felt cathode was developed for efficient landfill leachate concentrate treatment. Compared to electro-Fenton(EF) and electrocoagulation(EC) processes, the PC process was more cost-effective due to the combined action of·OH oxidation and iron hydroxides coagulation. A maximal TOC removal of 77.2% ± 1.4% was obtained after 360 min at initial p H = 5.0 and current density of 10 m A/cm^(2). After the PC process, concentrations of all seven heavy metals in the final effluents were below the allowable emission limits given by the present regulatory standards. The method preference for heavy metal removal was PC > EC > EF. Based on the three-dimensional fluorescence spectroscopy coupled with regional integration analysis during the PC treatment, the florescence peaks of both humic acids and fulvic acids disappeared after treatment for 360min. Decreasing trends were observed in the fluorescent regional standard volumes for aromatic protein Ⅰ(31.4%), aromatic protein Ⅱ(63.7%), fulvic acid-like(69.5%), soluble microbial by-product-like(75%) and humic acid-like regions(76.3%). The results indicate that comparing to the EF and EC process, the PC process provide a promising and more cost-effective alternative for the treatment of landfill leachate concentrate.
基金
supported by the National Key R&D Program of China(No.2018YFC1802500)
the National Natural Science Foundation of China(No.42077171)
the Special Fund of State Key Joint Laboratory of Environment Simulation and Pollution Control(No.20Y02ESPCT)。