Study On High Strength Organic Waste Water Treatment By Means Of MBR

Membrane bioreactor (MBR) is an effective method for reclamation of waste water. Waste water treatment by means of MBR can greatly save water resources, equipment and operating cost;reduce land occupied by equipment;avoid secondary pollution. At the same time, MBR has many good characters such as covering small area, high automation, convenient fitting and maintaining, etc. It represents the developing trend of waste water reclamation technique in our country. It has broad market outlook, together with large environmental, social and economic benefit.Three startup methods were tested in this paper. The results showed that the best startup way for organic waste water treatment was directly sucking water and raise the load gradually to domesticate sludge. The tested waste water was from a certain wine plant and had good biochemical nature. After 3.6 hours' anaerobic treatment and 5 hours' aerobic treatment, more than 95% of COD and 90% of ammonia nitrogen were removed. Three different aeration strength, 0.74m~3/(m~2.hr), 1.10m~3/(m~2.hr) and 1.47m~3/(m~2.hr), were tested in order to find the influence of aeration rate on treatment effect, membrane pollution and membrane resistance. It can be seen from the test result that the membrane operated more stably under higher aeration strength. In addition, the influence of different suction time on treated water quality after ceasing 2 minutes was tested also. The tested result tallied well with the theoretical calculation, nearly 5.7 minutes was the best suction time, it could reduce the membrane pollution by the greatest degree.In this paper, microorganisms phase of different stages of MBR were observed with electron microscope. The observation result showed that for different stages, the microorganisms phase for the system was different. Electron microscope observation was also made for the pollution of the membrane surface, and research of online cleaning of membrane has been done. The result showed that online cleaning with a shot of air and short time could remove the pollution layer of membrane surface better. The membraneflux could be improved about 30%.On the whole, the studying objectives of this difficult problem which treated high concentration organic waste water with MBR were as follows: studying the structure of different parts and MBR and their correlation;the removing effect for organic matter;the nitrification and denitrification of nitrogen;the influence of startup method, aeration rate, suction time and ceasing time on treatment effect and membrane pollution and resistance;the inherent laws of membrane surface pollution;and cleaning method for retrieving effect of membrane flux, etc. In this paper, the growing status of microbe in the operating process was studied microcosmically and the overall effect was valued macrocosmically from both waste water treatment and membrane pollution. In addition, the related technical problems in the technology engineering application were solved. Test acquired ideal results and provided further MBR study with some data and conclusions.