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Landfill leachate treatment with reverse osmosis (RO) process can inevitably generate membrane fouling, which increasing operation costs and declining system performance. Thus it is important to reveal the mechanism of fouling formation and propose the control approaches. In this paper, some pieces of waste RO membranes, which were collected from a Disk-Tube Reverse Osmosis (DTRO) system in a landfill site were determined. The surface aggregation state, chemical constitutions and ions species of surface inorganic contaminants on RO membrane fouling layer were characterized by Atomic Force Microscope(AFM), Scanning Electron Mictoscopy-X-ray Energy Dispersive Analysis(SEM-EDX), and Ion chromatography(IC), respectively. The results demonstrated that the fouling mass on the edge of the membrane was more larger than that on the centre, but there were no significant differences of components of the fouling substance. The main inorganic constitutions were barium and calcium carbonate and sulfate, SiO2, Al (OH)3, and Fe (OH)3 colloids. The initial ions from landfill leachate might form the precipitation of BaSO4, CaCO3 and CaSO4, MgCO3, Fe (OH)3 and FeCO3. Therefore, the precipitation from cations and anions in the landfill leachate is responsible for the inorganic fouling formation on the RO membrane. [ABSTRACT FROM AUTHOR]

Reverse osmosis (RO) is a dominant treatment technology for leachate produced in municipal solid waste (MSW) incineration plants and landfills. However, the RO application is restricted by membrane fouling. In this study, the foulants of disc tube reverse osmosis (DTRO) membranes from a MSW incineration plant and a landfill were characterized with different analytical techniques, including Atomic Force Microscope (AFM), Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDX), Fourier Transform Infrared Spectrometer (FTIR) and Three-dimensional Fluorescence Exceitation-Emission Spectrophotometer (3D-EEM). Results indicate that the floulant mass on the edge of the fouling layer was greater than that on the center of the layer. However, there was not any significant difference of elemental composition between the two locations. The main elements of fouling substance were C and O, while the minor elements include Mg, Al, Si, Fe, Ba and Ca. The functional groups of these foulants were mainly characterized with aromatic and polysaccharide structures. The primary organic pollutants on the RO membrane were fulvic acid and proteins. However, the protein types of the foulants on the RO membranes from the waste incineration plant and landfill were different. [ABSTRACT FROM AUTHOR]