Abstract A kinetic model of a nitrifying expanded-bed reactor for the pretreatment of drinking water was developed to analyze its behavior under different concentrations of influent dissolved oxygen, ammonium, and organic substrate. In laboratory, an up-flow expanded-bed reactor (linear velocity: 15.5 m/h, space velocity: 7.8 h−1, specific surface area: 5587 m2/m3) was initially fed with synthetic water containing 1 mg NHx-N/L to stimulate nitrifiers growth, followed by varied NHx-N loadings (1–2 mg NHx-N/L with a fixed linear velocity). From tracer tests, the hydraulic regime of the expanded-bed reactor was simulated to be 11 tanks-in-series. To model the even distribution of media in the expended-bed height, a mathematical internal recycle flow with biofilm media was made. The performances were also studied on the pilot- and full-scale reactors receiving river water in two water treatment plants in Vietnam. A single set of biological kinetic and stoichiometric parameters was elaborated that successfully reproduced the five different datasets over the lab-, pilot- and full-scale reactors. The attachment/detachment specific rates of the biofilm were estimated during filtration cycles and backwash events. The graphical guidance and empirical equation were provided to obtain the reactor treatment efficiency under variable influent and temperature.

中文翻译：

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饮用水预处理硝化膨胀床反应器的数学模型

摘要 建立了用于饮用水预处理的硝化膨胀床反应器的动力学模型，以分析其在不同浓度的进水溶解氧、铵和有机底物下的行为。在实验室中，上流式膨胀床反应器（线速度：15.5 m/h，空速：7.8 h-1，比表面积：5587 m2/m3）最初注入含有 1 mg NHx-N/的合成水。 L 刺激硝化菌生长，然后是不同的 NHx-N 负载（1-2 毫克 NHx-N/L，线速度固定）。从示踪剂测试中，膨胀床反应器的水力状态被模拟为 11 个串联的罐。为了模拟介质在扩展床高度的均匀分布，使用生物膜介质进行数学内部循环流。还在越南的两个水处理厂中对接收河水的中试和全规模反应堆的性能进行了研究。详细阐述了一组生物动力学和化学计量参数，成功地在实验室、中试和全规模反应器上重现了五个不同的数据集。在过滤循环和反冲洗事件期间估计生物膜的附着/分离特定速率。提供了图形指导和经验方程，以获得可变进水和温度下的反应器处理效率。在过滤循环和反冲洗事件期间估计生物膜的附着/分离特定速率。提供了图形指导和经验方程，以获得可变进水和温度下的反应器处理效率。在过滤循环和反冲洗事件期间估计生物膜的附着/分离特定速率。提供了图形指导和经验方程，以获得可变进水和温度下的反应器处理效率。