| Moving Bed Biofilm Reactor (MBBR) is a new type of membrane water treatment process that combined with the traditional activated sludge,biofilm and fluidization technology. It has many advantages,such as high treatment effieiency, volumetric loading large, strong impactand the advantages of small footprint and so on. This paper depends on the National water pollution control and management technology major projects (2008ZX07422003), MBBR was used in advanced treatment of artificial simulation of micro-polluted water and the experimental filler fluid status and fluid design optimization Pool studied.First of all, the treatment effects of the MBBR were well studied. Two-stage biological fluidized reactor were used in series. The status of the two-stage biological fluidized reactor natural biofilm formation and inoculated biofilm formation, which was studied in order to help to accelerate the start-up. Through changes in reaction parameters such as the filling ratio, aeration intensity and hydraulic retention time, the carbonaceous and nitrogenous removal capacity of MBBR in the micro-polluted water was investigated. The best reactor operating condition which is based on the experimental results of the analysis. The results showed that:(1) Biofilm formation of two ways during startup,under the temperature of 25±5, from CODMn and NH4+-N removal efficiency point of view, MBBR1 and MBBR2 were completed in 16 days biofilm formation and start, Don't add activated sludge will not cause biofilm formation and start time, compared with the two ways linked membrane biofilm thickness; (2) Under the conditions of ambient temperature, when HRT was 2h, aeration intensity was 5m3/m2, the removal of reactor reached the best. The removal rates of NH4+-N and CODMn reached 96% and 70%, and the effluent ammonia below 0.5mg/L, to meet standards for drinking water quality. (3) Under the conditions of low temperature(T=6-10℃), CODMn and NH4+-N removal efficiency decreased. NH4+-N removal rate decreased from 96% to 70%, CODMn removal rate decreased from 70% to 40%.(4) Under the conditions of low temperature, the reactor stops running, restart needs 6 days. Under the conditions of normal temperature, taking only 4 days to restart the reactor.To further study the impact of biological fluidized reactor pool removal of factors, this paper has suspended filler particle size on the four different streams of the state, and by CFD software to simulate the flow of pool within the gas-liquid two-phase flow to optimize the design and operation of pool conditions were studied. The results showed that:(1) To increasing weight of the packing, increasing packing density, can effectively improve the flow of packing effect; packing density is close to the water, streaming easier.(2) The flow of experimental results show that,10mm cylindrical packing fluid works well, it required low-intensity aeration, and can effectively remove CODMn and NH4+-N in the pretreatment experiments for micro-polluted water, it should be widespread used in water plant biological pretreatment. (3) Considering the development of a new packing, choose more suitable density of about 0.96-0.98g/cm3.(4) Fluent software to simulate aeration of Health through the logistics of the pool liquid two-phase interaction.Comparison of different aspect ratios, different diameter, different aeration tanks of gas and liquid flow rate of two-phase velocity distribution, compared to simulation results and found that the greater the aeration rate, aeration larger the circulation the greater the intensity of turbulence intensity and conducive to fluid mass transfer, increase the removal rate.(5) Simulated using Fluent software to encountered in the process to solve the operation of the reactor design and operation of the problems.
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