Experimental Study On Rural Sewage Treatment Of Vertical Flow Wetland And Intermittent Aeration Integrated Suspended Packing Bed

According to the characteristics and demand of rural decentralized governance sewage, biological and ecological composite technology which proposed to "intermittent aeration integrated suspended packing bed+ artificial wetland" process, and through a series of experimental studies, to determine the optimal process intermittent aeration integrated suspended packing bed, and on the basis of this study on removal effect the artificial wetland contaminant tremoval effect of nitrogen and phosphorus and the combination process,the following work has been done and the main research achievements are as follows:(l)The research on the integration of suspended packing bed, the process of intermittent aeration mainly includes:study the influence of some important factors of intermittent aeration integrated suspended packing bed, such as HRT, aeration tank aeration/stop aeration time ratio, reflux ratio, dissolved oxygen slurry. Based on the analysis of experimental results on the HRT, aeration tank aeration/stop aeration time ratio, reflux ratio, dissolved oxygen slurry process para-meters were determined; in the study of the rate of nitrification and the best process parameter system and denitrification,the system had strong nitrification, denitrification ability, nitrification rate, denitrification more efficient.(2)To obtain the best treatment effect of intermittent aeration integration of suspended packing bed in HRT=14h, aeration tank aeration/stop aeration time ratio is 3:1,the slurry reflux ratio is 150%,DO=3.5mg/L,CODCr, NH4+-N,TN,TP removal rate reached 87.28%,90.60%, 71.43%,50.42%,average effluent concentrations were 27.56mg/L,4.20mg/L,13.58mg/L,1.69 mg/L.Process for removal of pollutants except TP basic standard, artificial wetland is mainly for phosphorus removal,so can reduce or increase the load of wetland area,reduce the cost of the treatment.(3)Through the comparative analysis of artificial wetland during the no aeration and intermittent aeration process for nitrogen and phosphorus removal effect. Get the intermittent aeration is more conducive to the artificial wetland for removal of pollutants and can effectively solve the problem of clogging of constructed wetland, CODcr, NH4+-N, TN, TP removal average removal rates were 79.25%,99.75%,63.29,92.50%.The main mechanism of nitrogen in wetland systems is that the microenvironment hypoxia-absorption and wetland plants in aerobic alternation; the main mechanism of phosphorus removal is the assimilation of the wetland system of adsorption, microbial substrates and the absorption of plant.(4) Experimental study on removal effect on the best conditions of intermittent aeration integration of suspended packing bed and artificial wetland combined process of pollutants. The device of continuous operation monitoring, a combination process of CODcr,NH4+-N,TN, the average removal rate of TP reached 97.63%,100%,88.18%,97.33% respectively. Through the analysis of the monitoring data, the average concentration of the effluent were 5.14mg/L, 0mg/L,6.11mg/L,0.087mg/L, far below the "urban sewage treatment plant pollutant discharge standard" (GB-18918-2002) in an A standards.Research shows that:the intermittent aeration integrated suspended packing bed and artifi-cial wetland combined technology of rural domestic sewage treatment technology is a new tech-nology of biological and ecological treatment of an efficient combination.