Applied Research On Treatment Of Rural Domestic Sewage In Guanzhong Area By Hybrid Constructed Wetlands

The shortage of water resources in Guanzhong area,the unsynchronization of rural environmental construction and economic development make the problem of rural water environment pollution more prominent.The“Village Revitalization Strategy”proposed by the 19th National Congress will build an ecologically livable village as an important component.The construction of a domestic sewage treatment system suitable for the actual situation in the rural areas of Guanzhong is an urgent problem to be solved to improve its sanitary conditions and improve the environmental quality.At present,the basic data of rural domestic sewage discharge characteristics,major pollutants and various pollutants in Guanzhong area are lacking.The analysis of water quality and water quantity status can provide design basis and effective reference for rural domestic sewage treatment in Guanzhong area.Based on the rural sewage treatment project of Bigong Village in Yangling District of Shaanxi Province,this paper analyzes the treatment characteristics of Guanzhong rural domestic sewage and its composites by analyzing the water quality and water quality of several villages such as Bigong,Zhouli and Jiangyuan.The problem of design and application of sewage treatment engineering with artificial wetland as the main process.In order to solve the problem of odor generation in the combined artificial wetland system effluent deep purification unit and domestic sewage discovered during research and engineering design,hydroponic technology is the main technical means,and the static climate training is used to screen the climate characteristics and rural life in Guanzhong area.The hydroponic plants of sewage water quality and the reduction of odorous substances in sewage by the hydroponic plants in the test.Combined with the test results,the Bigong sewage treatment project was reconstructed and designed.The main research results are as follows:（1）Through the monitoring and analysis of domestic sewage water quality monitoring and discharge water volume changes in several villages and multiple sampling sites in Bigong,Zhou Li and Jiangyuan,the main changes of rural domestic sewage in the study area are as follows:NH₄⁺-N:1.0⁴4.6 mg/L;TP:0.8⁴.9 mg/L;SS:165.0³55.0 mg/L;COD:143.0⁷55.9 mg/L.Mainly manifested as ammonia nitrogen and organic pollution,and organic pollution is seriously exceeded.The daily discharge of sewage is extremely uneven.The peak period is mainly for the three meals of the villagers and the time before bedtime.The main reason for the fluctuation of water quality and water volume is the specific water supply mode of regular water supply in the village;the high organic pollution of sewage and the fluctuation of water quality and quantity Large-scale emission control facilities must be added to the wastewater treatment design process;（2）The removal rate of NH₄⁺-N by plant systems cultivated by planting basket,foam board and artificial air chamber was 58%,51%and 52%,respectively,and the removal rate of NO₃^--N reached 82%,93%and 86%,the removal rates of TP and COD were 58%,30%,42%and 60%,46%,56%,respectively;dissolved oxygen level is an important factor determining the removal of pollutants by hydroponic systems,under different planting methods The removal rate of NH₄⁺-N was significantly different（P<0.05）,mainly due to the different reoxygenation conditions of different colonization methods;the removal rate of N by three floating plants of Myriophyllum verticillatum L.,Pistia stratiotes and Eichhornia crassipes were better than that.The average level of water plants had no significant difference in the removal rate of nitrate and nitrogen,but the removal effect and stability of total phosphorus and COD by three floating plant systems were inferior to which of emergent plants;the optimal organic load of plants was 3.91×10^-3 kg/（m³·d）;（3）The gas sample collection device was designed to collect and scrub the odor-producing gas without obvious color and quality changes.The sensory measurement results showed that the degree of odor suppression of different hydroponic plant systems was different,compared with the odor-producing system.,Astragalus membranaceus,scallions,lycopene,reed can maintain good redox conditions during the reaction,which is beneficial to suppress the occurrence of odor;three-dimensional fluorescence analysis of effluent water sample shows that the odor can becaused by the system of aromatic protein Caused by classes and soluble microbial metabolites.（4）Based on the above research results,the reconstruction and design of the Bigongcun domestic sewage treatment project with a treatment capacity of 160 m³/d will be completed,and the main process determination will be completed,which will provide technical reference and reference for the comprehensive management of rural living environment in Guanzhong area.