Treatment Of Fresh Kelp Wastewater By Flocculation-Aerobic MBR Process

There has discharge a lot of wastewater in the kelp process. If this amount of wastewater was wasted without treatment, the drinking water source may be polluted, and the shortage of water resource will be more severe. For existing kelp wastewater treatment process, there exists problems such as complex treatment procedure, large footprint, large excess sludge production, unstable treatment performance, and etc.. Membrane bioreactor (MBR) is a kind of new technology on treating wastewater, combined biological method with membrane separation, it overcomes the above shortcomings. MBR has a lot of advantages, such as high volumetric load, high concentration sludge, the low rate of sludge production, operation and management convenient, auto-control etc.. So, it has been most attractive recently. In recent years, the labor input for the kelp drying too high costs, the State Ministry of Science and Technology are listed in a special carry out fresh kelp deep processing technology development, for fresh kelp processing wastewater treatment and reuse. In this paper a new process of flocculation-aerobic membrane bioreactor (MBR) for treatment of kelp wastewater presented, configured Asahi Kasei Corporation columnar PVDF hollow fiber membrane modules in the immerged MBR which is self-designed and manufactured for a specific pollutant of kelp wastewater treatment, and it mainly focus on the factors affecting HRT, sludge load, dissolved oxygen, and the optimum parameters determined. The results obtained are as follows:(1) Flocculate was used as the pretreatment of the aerobic membrane bioreactor, it possesses indispensability. PAC is used in the flocculate process. The best of treatment effect was obtained when pH value is around 7. PH of the raw wastewater was 6.2 because of without adjustment of pH. When PAC dosage was 0.8g/L, removal rate of COD, colority, SS, TP were above 28%,70%,70%,80%, respectively.(2) The operation of membrane bioreactor was stable with no sludge discharging. The removal rate of COD, NH3-N, HCHO were high, and the average removal rate of them were over 93%, especially, the HCHO's removal rate reached over 99%. But the removal effect of the TP was unsatisfactory, as the operation time was increased, the TP removal rate was decreased.(3) COD removal rate was significantly affected by HRT, DO, volumetric load, organic load. COD removal rate was risen markedly with increase of the HRT, DO and decrease of the volumetric load, sludge load. But change of HRT was no effect on NH3-N removal. The sludge concentration in the reactor rose with increased operation time, and the sludge activity also reduced after continued operation of 30d.The system average effluent of COD, NH3-N, TP, HCHO values less than 60mg/L,2mg/L, 1mg/L and 1mg/L, respectively, when the wastewater after treatment.