The Research Of New Airlifting-reflux Combined Decentralized Treatment Equipment Of Wastewater

Although decentralized wastewater treatment process has been applied in manyareas in recent years, but its disadvantages such as large floor space, complexequipment, hard to maintain have restricted its further application. This thesis aimedat shortcomings above-mentioned of decentralized wastewater treatment process, anairlifting-reflux combined reactor was proposed mainly treating rural sewage indecentralized areas. In a pilot study based on the actual project cases, integrateddevice processing performance was analysised and integrated structure of reactorwas optimized. Adapted influent concentration, operating costs and other importantapplication parameters were propose. The topic provided a scientific basis for forindustrial production and further promotion of the integrated device.The device was designed to come through the pilot project and the project’soperating statistics. The device has more stable removal efficiency of COD, NH4+-N,TN and SS than other same type of rural sewage treatment. Water indicators can bestability achieved "GB18918-2002" B standard ecxept Phosphorus. Reliable datawere provided for scale application and futher popularity of the apparatus.In this thesis，a pilot plant of10tons per day and engineering plant of20,50,80tons per day using the reactor devices were carried out to conduct preliminary study.The main results were presented as follows:（1）The airlifting-reflux combined reactor was proposed mainly treating ruralsewage, the results showed that the process can achieve a good removal effect. Theremoval effect of CODcr can be up to80%above on the average. The ammonianitrogen and total nitrogen can reach a good removal effect rate of90%and65%.The average effluent concentrations of suspended solids (SS) is20mg/L.（2）The airlifting-reflux combined reactor proposed for treating rural sewagein this paper has advantages as follows:The system can realize the unattended and have convenient operationmanagement.The system has sludge reduction process and long time don’t have to dredge.The system don’t need return sludge pump, so the energy consumption andinvestment cost are less.The integration of the equipment are high, installation is fast and convenient.The system need less equipment, the failure rate is lower. Based on an experimental test, the engineering process design, operationmanagement and technical and economic comparison of reactor was researched for10t/d pilot project in SuZhou. And then through the amplification works of20,50,80tons per day using the reactor devices were researched for the industrialproduction and further promotion of reactor to rural decentralized wastewater.