Ganesh R, Balaji G, Ramanujam R A
Department of Environmental Technology, Central Leather Research Institute, Adyar, Chennai, India.
Bioresour Technol. 2006 Oct;97(15):1815-21. doi: 10.1016/j.biortech.2005.09.003. Epub 2005 Oct 17.
This investigation proved that respirometry combined with sequencing batch reactor (SBR) could be an effective way for the removal of COD in tannery wastewater. Measurement of oxygen uptake rates (OUR) and corresponding COD uptake rates showed that a 12-h operating cycle was optimum for tannery wastewater. The removal of COD by degradation was stoichiometric with oxygen usage. A plot of OUR values provided a good indication of the biological activity in the reactor. A high OUR value corresponded to the feed period; at the end of the cycle, when the substrate was depleted, the OUR value was low. At a 12-h SBR cycle with a loading rate of 1.9-2.1 kgm(-3) d(-1), removal of 80-82% COD, 78-80% TKN and 83-99% NH(3)-N were achieved. These removal efficiencies were much higher than the conventional aerobic systems. A simple method of COD fractionation was performed from the OUR and COD uptake rate data of the SBR cycle. About 66-70% of the influent COD was found to be readily biodegradable, 10-14% was slowly degradable and 17-21% was non-biodegradable. The oxygen mass transfer coefficient, K(L)a (19 +/- 1.7 h(-1)) was derived from respirometry. It was observed that with the exception of high organic load at the initial feed the oxygen transfer capacity was in excess of the OUR, and aerobic condition was generally maintained. Simultaneous nitrification-denitrification was observed in the SBR during the feed period as proved by mass balance.
本研究证明，呼吸测定法与序批式反应器（SBR）相结合可能是去除制革废水化学需氧量（COD）的有效方法。对氧摄取率（OUR）和相应的COD摄取率的测量表明，12小时的运行周期对制革废水最为适宜。通过降解去除COD与氧气用量呈化学计量关系。OUR值的曲线图很好地表明了反应器中的生物活性。较高的OUR值对应于进料期；在周期结束时，当底物耗尽时，OUR值较低。在12小时的SBR周期、负荷率为1.9 - 2.1 kgm(-3) d(-1)的情况下，COD去除率达到80 - 82%，总凯氏氮（TKN）去除率达到78 - 80%，氨氮（NH(3)-N）去除率达到83 - 99%。这些去除效率远高于传统的好氧系统。根据SBR周期的OUR和COD摄取率数据，采用了一种简单的COD分级方法。发现进水COD中约66 - 70%易于生物降解，10 - 14%降解缓慢，17 - 21%不可生物降解。通过呼吸测定法得出氧传质系数K(L)a为（19 ± 1.7 h(-1)）。观察到，除了初始进料时的高有机负荷外，氧传递能力超过OUR，通常保持好氧条件。通过质量平衡证明，在SBR的进料期观察到了同步硝化反硝化现象。
