Technology and Water Quality Office, Public Utilities Board (PUB), Waterhub, 82 Toh Guan Road East #C4-03, Singapore 608576, Singapore.
Water Sci Technol. 2009;60(11):2829-39. doi: 10.2166/wst.2009.725.
A laboratory-scale system consisting of an upflow anaerobic sludge blanket (UASB) reactor followed by a modified Ludzack-Ettinger (MLE) activated sludge process was adopted to investigate COD and nitrogen removals in municipal sewage treatment in warm climate. The COD, SCOD, acetic acid (HAc), NH4+-N and PO4(3-)-P conversions in the UASB reactor were investigated. A 35% reduction in volatile suspended solid (VSS) was achieved in the UASB process. The net methane (CH4) production was 0.06 l (g COD(removed))(-1). Acids accumulation was not observed. In the MLE activated sludge process, nitrification was almost complete while denitrification was modest. Little excess sludge was produced as the bulk of the COD was removed in the UASB reactor, which reduced the COD mass load to the activated sludge process. The average COD and SCOD of the final effluent of the activated sludge process were 51 and 25 mg l(-1), respectively and the average NH4+-N concentration of the final effluent was 3.1 mg N l(-1). The results illustrated that the coupled process is feasible for COD and nitrogen removals in municipal sewage treatment in warm climate. However, the low pH of the final effluent (<6 on average) remains an issue to be solved.
采用上流式厌氧污泥床（UASB）反应器与改良的 Ludzack-Ettinger（MLE）活性污泥工艺相结合的实验室规模系统，研究了温暖气候下城市污水处理中的 COD 和氮去除。考察了 UASB 反应器中 COD、SCOD、乙酸（HAc）、NH4+-N 和 PO4(3-)-P 的转化。UASB 工艺实现了挥发性悬浮固体（VSS）减少 35%。净甲烷（CH4）产量为 0.06 l（g COD 去除）(-1)。未观察到酸积累。在 MLE 活性污泥工艺中，硝化几乎完全，而反硝化适度。由于大部分 COD 在 UASB 反应器中被去除，因此产生的剩余污泥很少，从而降低了 COD 对活性污泥工艺的质量负荷。活性污泥工艺最终出水的平均 COD 和 SCOD 分别为 51 和 25 mg l(-1)，最终出水的平均 NH4+-N 浓度为 3.1 mg N l(-1)。结果表明，该耦合工艺可用于温暖气候下城市污水处理中的 COD 和氮去除。然而，最终出水的低 pH（平均<6）仍然是一个需要解决的问题。
