Treatment of reverse osmosis (RO) concentrate from an old landfill site by Fe0/PS/O3 process

BACKGROUNDLarge volume of landfill leachate concentrate was generated from membrane treatment process, which contained large amount of toxic and refractory compounds. However, there is a lack of proper technologies for the treatment of membrane filtration concentrates. RESULTSAn effective method for treatment of landfill leachate reverse osmosis (RO) concentrate by Fe-0/PS/O-3 process was investigated to decompose the refractory pollutants and improve the biodegradability. First, the operating conditions including Fe-0 dosage, ozone aeration rate, PS (S2O82-) dosage and initial pH were optimized through single-factor experiment and response surface methodology (RSM) in this study. The results show that the method could obtain high COD (84.1%) and color (99%) removal efficiencies after 30min treatment under the optimal conditions. Meanwhile, BOD5/COD ratio was enhanced from 0.01 to 0.25, which suggests that its biodegradability was improved greatly. The decomposition or transformation of the organic pollutants in RO concentrate was analyzed by UV-vis, EEM and FTIR. Furthermore, the synergetic effect between Fe-0, PS and O-3 in Fe-0/PS/O-3 process was investigated according to the present literature and analysis date of SEM-EDS, XRD and XPS. CONCLUSIONSCollectively, a new Fe-0/PS/O-3 system was successful developed, and this system could be seemed as a promising technology for the treatment of reverse osmosis concentrate of landfill leachate. (c) 2017 Society of Chemical Industry