Rao N Chandrasekhara, Mohan S Venkata, Muralikrishna P, Sarma P N
Bioengineering and Environmental Center, Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500007, India.
J Hazard Mater. 2005 Sep 30;124(1-3):59-67. doi: 10.1016/j.jhazmat.2005.03.055.
The performance of granular activated carbon (GAC)-biofilm configured sequencing batch reactor (SBGR) in aerobic environment was investigated for the treatment of composite chemical wastewater [low BOD/COD ratio ( approximately 0.3), high sulfate content (1.75 g/l) and high TDS concentration (11 g/l)]. Composite wastewater was a combined mixture of effluents from about 100 chemical based industries. Reactor was operated under anoxic-aerobic-anoxic microenvironment conditions with a total cycle period of 24 h (fill: 15 min; reaction (aeration with recirculation): 23 h; settle: 30 min; decant: 15 min) and the performance of the system was studied at organic loading rates (OLR) of 1.7 kg COD/cum-day, 3.5 kg COD/cum-day and 5.5 kg COD/cum-day. The reactor showed efficient performance with respect to substrate degradation rate and sustained its performance at higher operating OLR (5.5 kg COD/cum-day) and at low BOD/COD ratio. Substrate utilization was found to increase with increase in the operating OLR. Maximum non-cumulative substrate utilization of 1.837 kg COD/cum-h, 2.99 kg COD/cum-h and 3.821 kg COD/cum-h was observed after 15 h of the cycle operation for operating OLRs of 1.7 kg COD/cum-day, 3.5 kg COD/cum-day and 5.5 kg COD/cum-day, respectively. Sulfate removal efficiency of 11+/-2% was recorded in the SBGR due to the induced anoxic conditions prevailing during the sequence phase operation of the reactor and the existing internal anoxic zones in the biofilm. Effective performance of the reactor may be attributed to sorption capacity of GAC as carrier material facilitating low toxicant concentration in the mixed liquor. The existing high flow rates around the GAC particle results in good mass transfer of the substrate from the bulk liquid. The long retention of biofilm on GAC increases the potential for the treatment of recalcitrant industrial wastewater. GAC configured biofilm configuration coupled with sequencing batch mode operation appears to be promising for the effective treatment of complex industrial wastewater containing poorly degradable compounds.
研究了颗粒活性炭（GAC）-生物膜组合序批式反应器（SBGR）在好氧环境中处理复合化学废水[低BOD/COD比（约0.3）、高硫酸盐含量（1.75 g/l）和高TDS浓度（11 g/l）]的性能。复合废水是约100家化工行业废水的混合液。反应器在缺氧-好氧-缺氧微环境条件下运行，总周期为24小时（进水：15分钟；反应（曝气并循环）：23小时；沉淀：30分钟；排水：15分钟），并在1.7 kg COD/立方米·天、3.5 kg COD/立方米·天和5.5 kg COD/立方米·天的有机负荷率（OLR）下研究系统性能。该反应器在底物降解率方面表现出高效性能，并在较高运行OLR（5.5 kg COD/立方米·天）和低BOD/COD比下维持其性能。发现底物利用率随运行OLR的增加而提高。对于1.7 kg COD/立方米·天、3.5 kg COD/立方米·天和5.5 kg COD/立方米·天的运行OLR，在循环运行15小时后，最大非累积底物利用率分别为1.837 kg COD/立方米·小时、2.99 kg COD/立方米·小时和3.821 kg COD/立方米·小时。由于反应器序批阶段运行期间存在诱导缺氧条件以及生物膜中现有的内部缺氧区，SBGR中记录的硫酸盐去除效率为11±2%。反应器的有效性能可能归因于GAC作为载体材料的吸附能力，有助于降低混合液中的有毒物质浓度。GAC颗粒周围现有的高流速导致底物从主体液体中的良好传质。生物膜在GAC上的长时间保留增加了处理难降解工业废水的潜力。GAC配置的生物膜结构与序批模式运行相结合，对于有效处理含有难降解化合物的复杂工业废水似乎很有前景。
