Karnchanawong S, Sawangpanyangkura T
Department of Environmental Engineering, Faculty of Engineering, Chiang Mai University, Thailand 50200.
Water Sci Technol. 2004;50(8):185-92.
The objective of this study was to investigate the performance of the upflow anaerobic sludge blanket (UASB) reactor as the pretreatment system for silk-dyeing wastewater. Two laboratory-scale UASB reactors, with working volume of 15.59 I, were used during May 1998 to June 1999. The actual wastewater was diluted to reduce ammonium ion toxicity on anaerobic bacteria. The experiments were conducted at the organic loading rates (OLRs) of 0.52, 1.01, 1.04, 1.54 and 2.56 kgCOD/(m3 x d), treating only wastewater generated from the acid-dye process of mixed-species raw silk. It took approximately 4 1/2 months to reach the steady-state conditions. It was found that the COD removal was in the ranges of 74.1-85.3%, except at OLR 2.56 kgCOD/(m3 x d) where efficiency significantly dropped to 55.2%. The apparent color removal was in the similar trend as COD. During the study periods, wastewater input had various color shades while the effluent generally looked pale yellowish. The methane generation rates ranged from 0.18-0.31 m3/kg COD removed, with methane composition 81.0-88.1% in biogas. The average granule size in the sludge bed had slowly increased to 0.73 mm in the last experiment. It can be concluded that the UASB reactor is suitable as a pretreatment system for silk-dyeing wastewater. An OLR of 1 kgCOD/(m3 x d) and an influent concentration diluted to 2,600 mgCOD/l are suggested while COD and apparent color removal efficiency of 80% and 70%, respectively, can be expected.
本研究的目的是考察上流式厌氧污泥床（UASB）反应器作为丝绸染色废水预处理系统的性能。1998年5月至1999年6月期间，使用了两个工作体积为15.59升的实验室规模UASB反应器。实际废水进行了稀释，以降低铵离子对厌氧细菌的毒性。实验在有机负荷率（OLR）为0.52、1.01、1.04、1.54和2.56 kgCOD/(m³·d)的条件下进行，仅处理混合生丝酸性染色过程产生的废水。达到稳态条件大约花费了4个半月的时间。结果发现，化学需氧量（COD）去除率在74.1%至85.3%之间，但在OLR为2.56 kgCOD/(m³·d)时，效率显著降至55.2%。表观颜色去除情况与COD的趋势相似。在研究期间，废水进水有各种颜色深浅，而流出物通常呈浅黄色。甲烷产生率在0.18至0.31 m³/kg COD去除量之间，沼气中甲烷含量为81.0%至88.1%。在最后一次实验中，污泥床中颗粒的平均尺寸缓慢增加到了0.73毫米。可以得出结论，UASB反应器适合作为丝绸染色废水的预处理系统。建议OLR为1 kgCOD/(m³·d)，进水浓度稀释至COD 2600 mg/l，预计COD和表观颜色去除效率分别可达80%和70%。
