| With the development of society,ecological residential become residential housing's development trend and fashion.Water is the basis of ecological residential quarter,the effective use of recycled water occupies a very important position in the planning and design of ecological residential quarter,"open source" is primary area links to achieve the quarter's use of resources.Water reuse is important ways to achieve sewage resources of the ecological residential quarter.The BAF(Biological Aerated Filter) technology Simple,efficient,low consumptive sewage treatment and reuse technology correspond to the situation of China. This paper focuses on the experinetal study in which the A/O integrated BAF was adopted on treatment of Quarter sewage.And determine the feasibility of A/O integrated BAF use in ecological residential quarter's water environmental system as a water reuse technology.In this paper,through experimetal study and theoretical analysis to confirm the optimum running parameters of the A/O integrated BAF,including gas-water ratio and hydraulic loading.And the experimente and analysis of biochemical characteristics along A/O integrated BAF and the factors which affect its performance,including temperature,pH, pollutants volume loading,different aeration location and backwashing were carried out;At the same time,phosphorus removal by biochemical synergistic precipitation, pre-denitrification and the activity ofbiofilm was studied.Volcanic rock was used as the media of A/O integrated BAF device.It took about 18 days to succeed in cultivating biofilm using of the method of start-up with inoculum,COD and NH3-N removal rate were stable at 75%and 90%.The experimental results showed that the removal rate of COD and NH3-N in A/O integrated BAF could reach to 78.14%and 89.75%on average.The optimum running parameters of the A/O integrated BAF were confirmed:gas-water ratio is 18:1,hydraulic loading is 0.5 m3/(m2·h).The analysis of biochemical characteristics along A/O integrated BAF showed the bacteria in the BAF spatial distribution characteristics. The heterotrophic bacteria degradating the organic stay in the lower filter because of its short generational cycle and fast breeding,so the COD was mainly removed in the lower 400mm of the filter;The nitrifiers distribute in upper of the filter because of nitrifiers in the competition with heterotrophs at a disadvantage,so nitrification occurred mainly in 400～1700 mm filter. SS basically trapped in the lower 800mm of the filter.Temperature and pH values due to different reaction occurred in the different parts of the filter.And it is confirmed that simultaneous nitrification and denitrification reacted through the analysis of inorganic nitrogen compounds along the filter.The factors affecting the performance of A/O integrated BAF include temperature,pH, pollutants volume loading,different aeration location and backwashing.With the temperature increasing,the COD removal gradually increased.With the pH value increases,COD removal rate decreases;And NH3-N removal declined slightly.When the COD volume loading in the 0.5～3.5 kg/m3·d,BAF has higher COD removal.With the COD volume loading increases, COD removal declined slightly.NH3-N removal declined with the increasing of COD volume loading,but the NH3-N removal rate is more than 70%when COD volume loading at 0.5～3.0kg/m3·d.Biological Aerated Filter still has high NH3-N removal rate when NH3-N volume loading at 0.15～0.30kg/m3·d.But NH3-N removal decreased slightly with NH3-N volume loading increased.As biological phosphorus removal less effective,phosphorus removal by biochemical synergistic precipitation was adopted.PAC was chose as Phosphorus Pharmacy,and the best dosage is 30 mg/L.It is determined that the experimental device's reflux ratio is 200%after the pre-denitrification experiment and analysis.Simultaneous nitrification and denitrification reacted in the filter,and denitrification occurred mainly in anaerobic micro-environment.The study on BAF biofilm activity indicated that the biomass is fewer in the non-aerated areas,but there's higher activity;there's rich biomass and higher activity in aerated areas of higher organic concentration;there's less biomass and lower activity nearby the outlet of the filter. The microscope showed that the direction of dominant species in the biofilm showed obvious push flow characteristics.The principle of the NH3-N removal of BAF is cleared through this paper,and to further define that the denitrification occurred mainly in anaerobic micro-environment;through the filter effluent water testing,water quality indicators have reached the "City of miscellaneous water quality standards",so A/O integrated BAF could use as a sewage treatment and reuse technology in water environment system of ecological residential quarter.
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