Liang Chung-Huei, Chiang Pen-Chi, Chang E-E
Graduate Institute of Environmental Engineering, National Taiwan University, No. 71, Chou-shan Road, Taipei 106, Taiwan.
Water Res. 2007 Aug;41(15):3241-50. doi: 10.1016/j.watres.2007.05.024. Epub 2007 May 21.
This investigation developed a non-steady-state numerical model to differentiate the adsorption and biodegradation quantities of a biological activated carbon (BAC) column. The mechanisms considered in this model are adsorption, biodegradation, convection and diffusion. Simulations were performed to evaluate the effects of the major parameters, the packing media size and the superficial velocity, on the adsorption and biodegradation performances for the removal of dissolved organic carbon based on dimensionless analysis. The model predictions are in agreement with the experimental data by adjusting the liquid-film mass transfer coefficient (k(bf)), which has high correlation with the Stanton number. The Freundlich isotherm constant (N(F)), together with the maximum specific substrate utilization rate (k(f)) and the diffusion coefficient (D(f)), is the most sensitive variable affecting the performance of the BAC. Decreasing the particle size results in more substrate diffusing across the biofilm, and increases the ratio of adsorption rather than biodegradation.
本研究建立了一个非稳态数值模型，以区分生物活性炭（BAC）柱的吸附量和生物降解量。该模型考虑的机制包括吸附、生物降解、对流和扩散。基于无量纲分析，进行了模拟以评估主要参数（填充介质尺寸和表观流速）对去除溶解有机碳的吸附和生物降解性能的影响。通过调整与斯坦顿数高度相关的液膜传质系数（k(bf)），模型预测结果与实验数据相符。弗伦德利希等温常数（N(F)）、最大比底物利用率（k(f)）和扩散系数（D(f)）是影响BAC性能的最敏感变量。减小颗粒尺寸会导致更多底物扩散穿过生物膜，并增加吸附而非生物降解的比例。
