Henrichs M, Welker A, Uhl M
Department of Civil Engineering, Laboratory of Water Resources Management, Muenster University of Applied Sciences, Corrensstrasse 25, Muenster FRG-48149, Germany.
Water Sci Technol. 2009;60(3):825-31. doi: 10.2166/wst.2009.397.
Biofiltration has proved to be a useful system to treat combined sewer overflow (CSO). The study presented uses numerical simulation to detect the critical operating conditions of the filter. The multi-component reactive transport module CW2D was used for the simulation study. Single-event simulations of lab-scale-column experiments with varying boundary conditions regarding the throttle outflow rate were carried out. For the calibration of the CW2D model measurement results of four experiments in two lab-scale columns were used. The model was validated by simulating four events of two further columns filled with the same filter material. These columns were operating with higher throttle outflow rates than the columns used for calibration. For ammonium (NH(4)-N) a good fit between measured and simulated data could be achieved. However, the comparison of simulated and measured effluent concentrations of nitrate (NO(3)-N) showed that there is a need for further investigations mainly due to the uncertainties in the degradation process during dry periods between the loadings.
生物过滤已被证明是一种处理合流制下水道溢流（CSO）的有效系统。本文所呈现的研究采用数值模拟来检测过滤器的关键运行条件。多组分反应输运模块CW2D被用于模拟研究。针对节流流出速率的不同边界条件，开展了实验室规模柱实验的单事件模拟。为校准CW2D模型，使用了两个实验室规模柱中四个实验的测量结果。通过模拟另外两个填充相同过滤材料的柱的四个事件对模型进行了验证。这些柱的节流流出速率高于用于校准的柱。对于铵（NH(4)-N），测量数据与模拟数据之间能实现良好拟合。然而，模拟和测量的硝酸盐（NO(3)-N）流出浓度的比较表明，主要由于两次负荷之间干旱期降解过程中的不确定性，仍需进一步研究。
