Study On Impact Resistance Of Purifying-Tank Connecting Multiple Septic Tanks

Since the reform and opening up, urbanization has made great progress, urban and rural people’s living standards greatly improved, the use of washing toilets and tap water were used in most newly built urban and rural, changing family living environment, while also posed a serious sewage pollution problems. At present, one-situ treatment of sewage, although individual septic tank technology development and practical application have been successful in rural areas of our country, due to the costs of production and consumption during processing costs still can not meet the development requirements of our country’s rural economy, so be widely promoted, there are still great financial difficulties, the urgent need for more practical, technical, low-cost operation of biological treatment plant.To point against the septic tank which matched rural water supply engineering, a new purifying-tank which combined with multi-family septic tank was developed on the basis of individual one. Two-stage anaerobic, one-stage aerobic was changed to one-stage anaerobic, two-stage aerobic process in the new purifying-tank, that increase aerobic biological treatment capacity, reduce equipment investment and running cost, achieve both a dispersed and relatively concentrated purification tanks treatment mode is more suitable for the new rural construction needs.The main contents of this paper were as followed:(1) The aeration rate is one of the key factors that influenced the operation cost,according to the optimum aeration have come to conclusions and to continue research on the purification efficiency of different aeration, optimize and determine the best aeration. The results showed that when aeration were one-stage2.4L/min, two-stage1.2L/min as optimum aeration conditions.(2) Experiment of inflow resistant impact:under the operating conditions of aeration were one-stage2.4L/min, two-stage1.2L/min, changed daily inflow, to discuss different inflow impact resistance on new purifying-tank. The results showed that when sewage inflow is50L/d(equivalent to the actual purifying-tank of six household sewage emission) the average effluent value of COD, BOD5, NH3-N and turbidity are22.67mg/L,7.8mg/L,8.3mg/L and1.79NTU, respectively. The new purifying-tank is better than the national primary standard. Even sewage inflow is70L/d, the effluent quality of BOD5is lower than20mg/L, prove that the new purifying-tank has a strong ability to resist the impact of inflow.(3) Experiment of sewage concentration impact:under the sameexperimental control conditions (aeration, temperature, etc.), changed influent concentration, to discuss different effluent concentration on impact resistance on new purifying-tank. The results showed that when the influent concentration of BOD5is about155mg/L, effluent concentration of COD, BOD5, NH3-N and turbidity area24mg/L,9mg/L,7.92mg/L,2.36NTU, meet the national emission standards. Even when the influent concentration of BOD5is280mg/L, BOD5effluent concentrations remained below20mg/L, prove that the new purifying-tank has high resistance o impact of sewage concentration.