A case study on effectiveness of a novel treatment process for purifying swine wastewater from large-scale piggery by using bio-coagulation dewatering followed by bio-oxidation
YE Tao;YAN Cheng;WANG Dianzhan;WANG Wenqiang;WU Zhenjiang;LIANG Jianru;ZHOU Lixiang;College of Resources and Environmental Sciences,Nanjing Agricultural University;Nanjing Bact Environmental Solutions Co.Ltd.;
In view of difficulty and high cost of conventional anaerobic-aerobic activated sludge technique to successfully treat swine wastewater for meeting effluent discharge standard, a novel approach called as bio-coagulation dewatering followed by bio-oxidation(BDBO) is developed. BDBO technique was applied in a piggery with 50 000 pigs located in Huizhou city, Guangdong province. The water quality indexes(COD, NH_3-N, TN and TP) of the effluent at different treatment stages in this project were investigated and determined for successive 4 months. The results showed that, in this BDBO process with only 2.5 d hydraulic retention time(HRT), the concentration of COD, NH_3-N, and TP of final effluent were decreased to(273±58),(44±9) and(4.5±1.0) mg·L~(-1) from initial(11 697±1 484),(837±25) and(532±97) mg·L~(-1) in influent with removal efficiencies of 97.7%, 94.7%and 99.2%, respectively. Obviously, the effluent quality was much superior to the relative discharge standard by Guangdong province(DB 44/613-2009). Moreover, its operating cost was only about 6 yuan·t~(-1), which was about1/2 to 1/3 of the costs with conventional anaerobic-aerobic activated sludge system. In addition, BDBO process also improved efficiently advanced dewatering of sewage sludge. The above-mentioned merits exhibited by BDBO process were found to be mainly attributed to absolutely removal of SS prior to A~2/O stages. As a result, most of COD, P and partial N in the form of SS in the influent could be greatly reduced before the influent was treated with anaerobic-aerobic activated sludge technique. This already-pretreated influent only containing soluble COD, N and P due to completely removing SS was much easier for water purification through consequent A~2/O processes. The novel BDBO process is of a great application prospect in the field of animal wastewater treatment because of a short HRT, meeting easily discharged standard(especially for NH_3-N), and efficient operating cost.
【CateGory Index】： X713
【CateGory Index】： X713