ABSTRACT

Down-flow hanging sponge (DHS) reactor that is sponge-based trickling filter was considered to be an alternative aerobic treatment system for low strength sewage treatment under tropical conditions. This study aims to determine the process performance of the DHS reactor combined with a pre-treatment sedimentation tank (SED) system installed at the municipality sewage treatment plant in Khon Kaen, Thailand over, 1,600 days. The DHS reactor was operated with three operational periods: low (0.2 kgBODm³ per day), high (0.5–1.3 kgBODm³ per day), and super rates (1.7–2.2. kgBODm³ per day). The results showed effective reductions in biochemical oxygen demand (BOD) and suspended solids by more than 74% and 78%, respectively, during the entire experimental period. Moreover, the final effluent met the Thailand discharge standard with an external short hydraulic retention time of 0.2 h. In addition, the combined system facilitates simultaneous nitrification and denitrification and effectively removed up to 43% of total nitrogen. The self-degradation of the organic compounds occurs owing to the retained sludge in the DHS reactor; this leads to undisputed clogging in sponge media. Therefore, the combined SED-DHS system could be an appropriate sewage treatment system for tropical conditions.

摘要

下流悬挂海绵（DHS）反应器是基于海绵的滴滤器，被认为是热带条件下低强度污水处理的替代好氧处理系统。本研究旨在确定 DHS 反应器与安装在泰国孔敬市政污水处理厂的预处理沉淀池 (SED) 系统相结合的 1,600 多天的工艺性能。DHS 反应器以三个运行阶段运行：低（每天 0.2 kgBODm ³）、高（每天 0.5–1.3 kgBODm ³）和超速率（1.7–2.2. kgBODm ³每天）。结果表明，在整个实验期间，生化需氧量 (BOD) 和悬浮固体分别有效降低了 74% 和 78% 以上。此外，最终出水符合泰国排放标准，外部短水力停留时间为 0.2 小时。此外，该组合系统有助于同时进行硝化和反硝化，并有效去除高达 43% 的总氮。由于 DHS 反应器中的滞留污泥，有机化合物发生自降解；这导致海绵介质中无可争议的堵塞。因此，组合的 SED-DHS 系统可能是适合热带条件的污水处理系统。