Informação Geral

In order to objectively elucidate the state of the membrane after long-term operation, the performance of a full-scale microfiltration-reverse osmosis (MF-RO) integrated membrane system with production capacity of 20,000 m³/d for wastewater reclamation was evaluated by collecting 10 years performance data. The foulants on 1 MF membrane and 12 RO membranes along the feed channel also were analyzed by membrane autopsy. The results indicate that the water quality of the system can still meet the customer requirements while the mechanical and desalting properties of the membranes were close to the abandoned standards. In terms of foulants distribution, the MF membrane surface was covered by a thick cake layer and the leading RO membrane suffered the highest fouling load. The predominate organic foulants on the membrane surface were protein and polysaccharide, and the main inorganic foulants were Fe and Ca, and their distribution showed two different trends along the feed channel. Regarding bio-foulants, the compositions of bacterial colonies on 12 RO membranes were basically the same, but the relative abundance of the dominant bacteria was different and the microbial diversity increased gradually from the leading element to the terminal one in both the two stages.