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At present, the research and development of natural processing system which covers a small area, operates more efficiently with low expenses and low energy consumption, is one of the topics which are being taken seriously into consideration abroad and internally. The mixed wastewater consisting of sanitary waste from kitchen and closet, septic tank outlet from closet and canteen, and so on, in which varieties of pollutants are in high concentration, belong to high concentration domestic sewage and must be processed to meet relative standards and regulations to discharge. Acorrding to this case, in view of concept of single-family water treatment system and natural processing system and principle of green energy-saving, I designe a micro-power integrate baffle plate reactor applying to the high concentration domestic sewage processing, and do a series of experimental research. In the reactor, anaerobic processing (A), oxygenic processing (O), anaerobic processing (A) and oxygenic processing (O) are utilized to process raw domestic sewage along the flow direction.In the experiment of high concentration sewage processing, I do analysis, validation and evaluation of the purification ability of the reactor and its packing, and obtain the reactor’s optimum design parameters and controllable conditions in its operation.The main results are as follows:1. Inoculation experiment invetigates the startup of reactor of anaerobic activated sludge-aerobic biological membrane under normal temperature conditions, with fixed raw water quality and long HRT. Inoculation of anaerobic activated sludge and aerobic biofilm keep uniform and synchronous, and time used in this process is determined by anaerobic activated sludge inoculation. After about 55 days, startup of reactor succeedes, quality of each treatment chamber outlet is stable and satisfactory. In Aerobic Chamber One, the main biological indicators are vorticella, rotifer and arcella. Additionally, inoculum of microorganisms comes from a sewage treatment plant in xi’an.2. The data shows that in optimum operating conditions (the third condition), Nv is 0.26 kgCOD/m3·d, the removal rate of COD, NH4+-N and TN respectively comes up to 94.76%, 59.82%and 34.52%. And, in the first anaerobic chamber of Anaerobic Chamber One, Nv is 1.576kgCOD/m3·d, Ns is 0.07649kgCOD/kgMLSS·d,the removal rate of COD comes up to 88.22%. In the second anaerobic chamber of Anaerobic Chamber One, Nv is 0.003472kgCOD/m3·d, Ns is 0.0001695kgCOD/kgMLSS·d, the removal rate of COD comes up to 88.42%. In Aerobic Chamber One, Nv is 0.03718kgCOD/m3·d, the nitrification load is 0.1651kgNH4+-N/m3·d, and the removal rate of COD and NH4+-N respectively comes up to 91.38% and 61.81%. In Deep Processing Chamber, the nitrification load is 0.0447kgNH4+-N/ m3·d, the removal rate of NH4+-N comes up to 51.44% itself.3. In the recovery experiment of removal efficiency of ammonia nitrogen (NH4+-N), HRT changes from 23.1 hours to 36.96 hours, and the reactor operates continuously for 7 days. Howerer, NH4+-N concentration of reactor outlet is higher, floating in a small range which indicates that it is difficult to recover. Then the dissolved oxygen of Aerobic Chamber One is increased and, after 4 days, the NH4+-N removal efficiency is gradually enhanced, and then comes stable. Finally, it recovers to the level of case in which HRT is 36.96 hours.4. Orthogonal test data shows that the most important factors affecting removal efficiency are water flow rate and oxygen while aeration intermittent time is a greater factor which affects TN removal rate.5. According to biological phase analysis, anaerobic, hypoxia phase microorganisms mainly include bacteria relative to the anaerobic digestion (methane fermentation) and denitrifying bacteria. Aerobic phase microorganisms mainly include nitrite bacteria and nitrobacteria. The main biological indicators are vorticella, rotifer and arcella.
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