Anaerobic and Microaerobic Operation for the EGSB Reactor Treating Actual Coking Wastewater
To determine if anaerobic microniches are created granular sludge exposed to oxygen where the refractory organics reduction in coking wastewater could occur and to assay feasibility of the highly efficiently and stable operation of micro-aerobic EGSB reactor for simultaneous removal of COD and NH3-N treating actual coking wastewater at 25-30℃, both anaerobic and microaerobic operations of the EGSB reactor were considered. And the granular characteristic of activity, settling, and size was also investigated in this paper. By controlling oxygenation rate in the aeration column, different concentrations of dissolved O2 were generated in the circulating fluid which supplied dissolved O2 to the granule sludge bed in the EGSB reactor and to generate micro-aerobic environments. The results showed that, at 25-30℃, treating actual coking wastewater with 1280-2024mg.L-1 COD concentration, 50-112mg.L-1 NH3-concentration, the anaerobic EGSB reactor could only have 40.1%, 56.7% average COD removal efficiencies and 8.3% average NH3-N removal efficiencies (the negative NH3-N removal was usually appeared and even low to -77.8%) with 1.3L.-1, 0.6L-influent flow and 9.2h, 20h HRT, respectively. But microaerobic EGSB reactor could have average COD and NH3-removal efficiencies of 83.0% and 67.1%, respectively. Supplement dose of Oxygen for the microaerobic EGSB reactor was controlled by redox potential (ORP), and the ORP in inlet of the micro-aerobic EGSB reactor should be kept at about+35mV. Oxygenation could shift the population distribution smaller or larger particles compared to the anaerobic EGSB reactor and decreased the settled velocity of the granules (low 12m.h-1), but without any sludge washout. And the micro-aerobic EGSB reactor could keep about 38.0gMLSS.L-1 sludge concentration and 0.65 MLVSS/MLSS. The methanogenic activity of the granular sludge in the micro-aerobic was decreased, and even higher than in the strictly anaerobic EGSB reactor.
Dong Chunjuan Geng Zhaoyu Wang Yanxia Wang Zengzhang
Department of Environmental Engineering Taiyuan University Taiyuan, 030009, China College of Environment Science and Engineering Taiyuan University of Technology Taiyuan, 030024, Chi
国际会议
成都
英文
1-4
2010-06-18（万方平台首次上网日期，不代表论文的发表时间）