Bio-Filter Barrier Technology In The Ttreament Of Black And Smelly Water

With the rapid development of economy and urbanization in China,the problem of water environmental pollution is increasingly serious,which not only reduces the quality of life of urban residents,but seriously restricts the good development of cities in China.Due to the various and complex causes of black and smelly water,it is difficult to achieve the ideal effect by using a single technology,so it is necessary to combine appropriate processes for treatment.Therefore,in the background of the state and governments at all levels are constantly improving the requirements for the regulation of black and smelly water,seeking economic and feasible treatment solutions has become the key to solve the problem.After field investigation and water quality evaluation on eight rivers in the main urban area of Chongqing,the reasons for the formation of black and smelly water and the water quality status of the rivers in the main urban areas were further understood.Then combined the principle of biological technology and permeable reaction barrier technology(PRB),an experimental study was carried out on the operating conditions and treatment effects of the application of bio-filter barrier technology in the treatment of polluted water.The research contents include the water quality evaluation of some rivers in the main urban area of Chongqing,the selection of high efficiency fillers,the factors affecting the adsorption performance of the fillers,the factors affecting the adsorption performance of fillers,and the application of bio-filter barrier device to treatment of polluted water.The main results obtained are as follows:(1)In this paper,eight rivers in six districts of Chongqing were selected to carry out field investigation and their water quality was evaluated by the method of comprehensive index evaluation.The results showed that the comprehensive water quality marking index of Huaxi River and Xiaojia River reached the class III standard.The comprehensive water quality marking index of Kuxi River and Huangxi River reached IV standard,and Panxi River reached V standard.Qingshui Creek,irrigated Lan Creek and Taohua Creek belong to inferior Class Vstandard.The above rivers are not black and smelly water,but the problem of TN,NH4+-N,TP exceeding the standard is more prominent.(2)by comparing the adsorption effects of five kinds of fillers on the adsorption of pollutants in water,the comprehensive adsorption effects of ceramsite,zeolite and activated carbon are more prominent.The effects of adsorption time,pH,pollution load and the ratio of composite fillers on the adsorption capacity of composite fillers were investigated.(3)Through the comparison of the treatment effects of three different microbial agents on the polluted water,a kind of microbial bacterial agent with the best comprehensive degradation effect on pollutants in water was selected for follow-up test.It can be obtained by orthogonal experiment:?the optimum conditions for removal of NH4+-N and TN respectively were microbial immobilization time of 24 hours,rotation speed of 190 r/min,and packing ratio of 2:2:1.?The optimum conditions for removal of CODMn respectively were microbial immobilization time of 24 hours,rotation speed of 150 r/min,and packing ratio of 1:2:1.?The optimum conditions for removal of TP respectively were microbial immobilization time of 24 hours,rotation speed of 150 r/min,and packing ratio of 2:2:1.? The optimum conditions for removal of TOC respectively were microbial immobilization time of 18 hours,rotation speed of 150 r/min,and packing ratio of 2:2:1.(4)The test of treating artificial sewage with bio-filter barrier simulation device showed that the removal effect of bio-filter barrier on all pollutants was basically stable when the device was started for 14 days,and the degradation effect of TOC was the best at this time,with the removal rate of 88.839%;The degradation effect of NH4+-N was poor,and the removal rate was 65.970%.The degradation effect of TP,CODMn and TN were 86.763%,79.326%and 75.911%,respectively.(5)The effects of different hydraulic retention time(HRT)on the removal efficiency of bio-filter barrier were investigated.The results showed the highest removal rate of NH4+-N was about 75%,and the removal rates of TOC,TP,CODMn and TN were respectively up to 82%when HRT were between 6 and 8 hours.At this time,the reactor can not only guarantee the better treatment effect of polluted water,but also satisfy the requirement of economic rationality in practical engineering application to a great extent.