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Membrane bioreactor (MBR) is a new, highly efficient biological treatment technology, a combination of membrane separation technology with biological treatment technology, has the advantage of many other water treatment processes do not have much in recent years, researchers have concern. This test uses membrane bioreactor treatment saline sewage, dosing sewage inorganic salts (analytical grade NaCl). Monitoring with the increase in salinity, organic matter, nitrogen removal efficiency and membrane flux changes in the system. First static test, in the case of the other conditions unchanged, increasing salinity to 5.0% to 0.5% (salt content of 5 g / L) gradient of salinity changes in the observing system microbial activity and pollution changes in the concentration of mud. The results show that when the salinity of less than 3.0%, the sludge shape and flocculation change significantly. When the salinity of 3.0%, the surface of the sludge mixture inside the reactor surfaced a small amount of yellow, delicate, seemingly sticky Smooth sludge, no longer exist in the form of floc, but will be separated from the reactor, even after settling properties, the supernatant yellow sludge flocculation and sedimentation deteriorate. Salinity continues to increase, the amount of the above-state sludge, sludge morphology change significantly, the floc becomes loose, settling changes color gradually darkens sludge sludge mixture, the supernatant The fluid also more turbid; sludge flocculation and sedimentation poorly when salinity of 5.0%, the sludge mixture hair black dark, the supernatant was very turbid. Salinity from 5.0% dump more sludge completely black metamorphic basically lost, flocculation and sedimentation, the supernatant was extremely muddy. Thus, high salinity and salinity sudden changes will inhibit microbial metabolism, thus affecting sludge flocculation and settling properties, and change to a salt-free environment, a greater impact from the high salinity. Dynamic test is then carried out, changing the processing conditions, monitoring water quality, and to determine the optimum operating conditions of the treatment effect of the reactor. Then change gradient of 0.5% and the system salinity increased from zero to 4.0%, to monitor water quality (CODMn, ammonia nitrogen, total nitrogen), and sludge concentration and membrane flux variations, based on experimental data, analyzed and summarized processing sewage effect of salinity on membrane bioreactor. The results showed that when the salinity was 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, the system organics average removal rates were 84.0%, 81.8%, 78.1%, 76.0% , 75.5%, 74.4%, 47.1 system average ammonia nitrogen removal rate were 91.9%, 90.6%, 90.1%, 87.7%, 87.1%, 89.7%, 84.0%, 79.5%, the system total nitrogen average removal rates for %, 41.1%, 35.7%, 33.8%, 31.2%, 30.3%, 27.8%, 25.1%. Membrane pollution is mainly caused by microorganisms secrete extracellular polymeric system. The impact of salinity on membrane fouling was mainly due to salinity have a great impact on the microbial metabolic system. Increased salinity, increased concentration and viscosity of the sludge mixture in the system, so that the concentration of extracellular polymeric system increases, thus accelerating the speed of membrane fouling.
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