Modular Constructed Wetland And Preliminary Pilot Scale Trial On Sewage Treatment

At present,China is in short of water resources,and is facing serious water pollution and insufficient sewage treatment,while constructed wetlands?CWs?have the advantages of low energy consumption,good effluent quality,low economic cost and operation and maintenance costs,as well as high aesthetic value.It can effectively promote the degree of sewage treatment,so as to alleviate the problem of serious water pollution and water resources shortage.In the new CWs practical application,the traditional construction method often has a large project quantity,a long construction period,and it is difficult to achieve integrated installation,so it is difficult to guarantee the engineering quality;and the traditional construction method has more on-site work,which may bring more hidden safety problems during construction;Meanwhile,the investment of labor force,formwork materials etc.will lead to more resource consumption.In addition,during the on-site conventional construction,the dust,noise,construction waste etc.will further cause environmental problems.In view of this,this paper summarizes and discusses the problems existing in the practical application of CWs,such as the area occupation and the influence of low temperature.Based on our research group's independent research and development of modular CWs with proprietary property rights,the design concept and construction technology of modular CWs are described in detail.It followed by the first pilot-scale modular CW trial.In order to provide technical support and operation reference for the further promotion and application of CWs.The results of the pilot trial have demonstrated a good removal efficiency of organic matter and phosphorus,while the average removal rates of COD and TP were 66.45% and 94.41%,respectively,so that the average concentration of COD and TP in the effluent is about 39.87 mg/L and 1 mg/L,respectively.However,the removal effect of nitrogen in this experiment was relatively poor.The average concentrations of TN and NH₄⁺-N in the effluent were 29.65 mg /L and 27.44 mg /L,respectively,and the average removal rate is about 55% for both NH₄⁺-N and TN.Obviously,the nitrogen removal of the system still needs to be further studied.It is expected that through this study described in this thesis,the new technology of modular CWs and the possible strengthening measures to overcome the negative effects of low temperature in CWs can be applied in CW practice to achieve the efficient,economic and temperature in CWs can be applied in CW practice to achieve the efficient,economic and eco-friendly performance of CWs.If this is the case,better application of CWs technology can be adopted to improve the stability of wastewater treatment and thus to popularize the CWs in our country.It also speeds up the wastewater treatment degree and accordingly alleviates the problem of water pollution satiation.