Water Environ Res. 2012 Aug;84(8):646-55. doi: 10.2175/106143012x13373550426670.
The aim of this study was to expand the International Water Association Activated Sludge Model No. 2d (ASM2d) to account for a newly defined readily biodegradable substrate that can be consumed by polyphosphate-accumulating organisms (PAOs) under anoxic and aerobic conditions, but not under anaerobic conditions. The model change was to add a new substrate component and process terms for its use by PAOs and other heterotrophic bacteria under anoxic and aerobic conditions. The Gdansk (Poland) wastewater treatment plant (WWTP), which has a modified University of Cape Town (MUCT) process for nutrient removal, provided field data and mixed liquor for batch tests for model evaluation. The original ASM2d was first calibrated under dynamic conditions with the results of batch tests with settled wastewater and mixed liquor, in which nitrate-uptake rates, phosphorus-release rates, and anoxic phosphorus uptake rates were followed. Model validation was conducted with data from a 96-hour measurement campaign in the full-scale WWTP. The results of similar batch tests with ethanol and fusel oil as the external carbon sources were used to adjust kinetic and stoichiometric coefficients in the expanded ASM2d. Both models were compared based on their predictions of the effect of adding supplemental carbon to the anoxic zone of an MUCT process. In comparison with the ASM2d, the new model better predicted the anoxic behaviors of carbonaceous oxygen demand, nitrate-nitrogen (NO3-N), and phosphorous (PO4-P) in batch experiments with ethanol and fusel oil. However, when simulating ethanol addition to the anoxic zone of a full-scale biological nutrient removal facility, both models predicted similar effluent NO3-N concentrations (6.6 to 6.9 g N/m3). For the particular application, effective enhanced biological phosphorus removal was predicted by both models with external carbon addition but, for the new model, the effluent PO4-P concentration was approximately one-half of that found from ASM2d. On a PO4-P removal percentage basis, the difference was small, that is, 94.1 vs. 97.1%, respectively, for the ASM2d and expanded ASM2d.
本研究旨在扩展国际水协会活性污泥模型 2d（ASM2d），以涵盖一种新定义的易生物降解基质，该基质可在缺氧和好氧条件下被聚磷菌（PAOs）消耗，但在厌氧条件下不能被消耗。模型的改变是在缺氧和好氧条件下添加一个新的基质成分和过程术语，以用于 PAOs 和其他异养菌。波兰格但斯克（Gdansk）污水处理厂（WWTP）采用改良的开普敦大学（UCT）工艺进行营养物去除，为模型评估提供了现场数据和混合液进行批量测试。原始的 ASM2d 首先在动态条件下进行了校准，使用沉淀废水和混合液的批量测试结果进行校准，其中跟踪了硝酸盐摄取速率、磷释放速率和缺氧磷摄取速率。使用全尺寸 WWTP 中 96 小时测量活动的数据进行了模型验证。使用乙醇和杂醇油作为外部碳源进行的类似批量测试的结果用于调整扩展 ASM2d 中的动力学和化学计量系数。基于添加补充碳源到 UCT 工艺缺氧区对模型的影响预测，对这两种模型进行了比较。与 ASM2d 相比，新模型在使用乙醇和杂醇油进行的批量实验中更好地预测了缺氧条件下的碳需氧量、硝酸盐氮（NO3-N）和磷（PO4-P）行为。然而，当模拟在全尺寸生物营养去除设施的缺氧区添加乙醇时，两种模型都预测了相似的出水 NO3-N 浓度（6.6 至 6.9 g N/m3）。对于特定的应用，两种模型都预测了添加外部碳源时的有效强化生物除磷，但对于新模型，出水 PO4-P 浓度约为 ASM2d 的一半。基于 PO4-P 去除百分比，差异很小，即 ASM2d 和扩展 ASM2d 分别为 94.1%和 97.1%。
