Department of Biotechnology and Environmental Sciences, Thapar University, Patiala, 147004, Punjab, India.
Environ Sci Pollut Res Int. 2012 Nov;19(9):3906-13. doi: 10.1007/s11356-012-0976-z. Epub 2012 May 30.
This study evaluates the effect of integrated solar-assisted advanced oxidation process (AOP) and biological treatment on the extent of degradation of effluents from chlorination (C) and first alkaline extraction (E(1)) stages of soda pulp bleaching in agro-residue-based pulp and paper mill. Biodegradation of the effluents was attempted in suspended mode using activated sludge from the functional pulp and paper industry effluent treatment plant acclimatized to effluents in question. The photocatalytic treatment was employed using zinc oxide (ZnO) in slurry mode for decontamination of effluents in a batch manner and the degradation was evaluated in terms of reduction in chemical oxygen demand. The biological treatment (24 h) of C and E(1) effluent resulted in 30 and 57 % of degradation, respectively. Solar-induced AOP of C and E(1) effluents resulted in 53 and 43 % degradation under optimized conditions (2.5 g L(-1) ZnO at pH 8.0) after 6 h of exposure. For C effluent, a short duration of solar/ZnO (1 h) prior to biological treatment reduced the time required at biological step from 24 to 12 h for almost same extent (92 %) of degradation. However, sequential biological treatment (24 h) followed by solar/ZnO (2 h) resulted in 85.5 % degradation. In contrast, in the case of E(1) effluent, sequential biological (24 h)-solar/ZnO (2 h) system effectively degrades effluent to 95.4 % as compared to 84.8 % degradation achieved in solar/ZnO (2 h)-biological treatment (24 h) system. In the present study, the sequencing of photocatalysis with the biological treatment is observably efficient and technically viable process for the complete mineralization of the effluents.
本研究评估了集成太阳能辅助高级氧化工艺 (AOP) 和生物处理对农作物残余浆纸厂制浆漂白一氯碱抽提（CE）和第一段碱抽提（E1）阶段废水中污染物降解程度的影响。采用功能纸浆和造纸厂废水处理厂适应于所研究废水的活性污泥，在悬浮状态下尝试对废水进行生物降解。采用浆态氧化锌 (ZnO) 进行光催化处理，以分批方式对废水进行净化，并根据化学需氧量的降低来评估降解效果。CE 和 E1 废水的生物处理（24 小时）分别导致 30%和 57%的降解。在优化条件下（pH 值为 8.0 时，2.5 g/L ZnO），太阳能诱导的 AOP 对 CE 和 E1 废水分别在 6 小时后导致 53%和 43%的降解。对于 CE 废水，在生物处理前进行短时间的太阳能/ZnO（1 小时）处理可将生物处理所需的时间从 24 小时缩短至 12 小时，达到几乎相同的降解程度（92%）。然而，随后进行的顺序生物处理（24 小时）继之以太阳能/ZnO（2 小时）处理可实现 85.5%的降解。相比之下，对于 E1 废水，顺序生物处理（24 小时）继之以太阳能/ZnO（2 小时）系统可有效将废水降解至 95.4%，而太阳能/ZnO（2 小时）-生物处理（24 小时）系统的降解程度为 84.8%。在本研究中，将光催化与生物处理相结合的顺序处理是一种高效且可行的技术，可实现废水的完全矿化。
