Regional Environment Conservation Division, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan.
Department of Civil Engineering and Architecture, National Institute of Technology, Tokuyama College, Gakuendai, Shuunan, Yamaguchi, Japan.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2022;57(5):413-419. doi: 10.1080/10934529.2022.2073764. Epub 2022 May 10.
In the production of natural rubber, formate or acetate is added to the latex solution to coagulate the rubber; therefore, the wastewater contains high concentrations of organic acids, requiring the application of anaerobic treatment technology. In this study, a two-phase continuous flow experiment using a laboratory-scale upflow anaerobic sludge blanket (UASB) was conducted to investigate the influence of formate inflow on the microbial and physical characteristics of the retained granular sludge. In phase 1, acetate-based wastewater was used as feed, while in phase 2, formate-based wastewater was used as feed. In phase 1, the UASB exhibited high COD removal efficiency (97.2%); in addition, the retained sludge showed increased methane production from acetate and proliferation of acetate-utilizing species. In phase 2, the UASB performed as well as phase 1, with 98.2% COD removal efficiency. Microbial community structure analysis confirmed that relatives of present in the retained sludge were responsible for the degradation of formate in phase 2. However, decreased diameter and slight deterioration of granular sludge settleability were observed. In conclusion, formate inflow has low risk of interference with the process performance of the UASB, but it has negative effects on the physical properties of the granular sludge.
在天然橡胶的生产过程中，向胶乳溶液中添加甲酸盐或乙酸盐以凝固橡胶；因此，废水中含有高浓度的有机酸，需要采用厌氧处理技术。本研究采用实验室规模上流式厌氧污泥床（UASB）进行了两相连续流实验，以研究甲酸盐流入对保留颗粒污泥的微生物和物理特性的影响。在第 1 阶段，使用基于乙酸盐的废水作为进料，而在第 2 阶段，使用基于甲酸盐的废水作为进料。在第 1 阶段，UASB 表现出高 COD 去除效率（97.2%）；此外，保留的污泥显示出乙酸产甲烷量增加和乙酸利用物种的增殖。在第 2 阶段，UASB 的性能与第 1 阶段一样，COD 去除效率为 98.2%。微生物群落结构分析证实，保留污泥中存在的与 相关的微生物负责第 2 阶段中甲酸盐的降解。然而，观察到颗粒污泥的直径减小和略微恶化的沉降性能。总之，甲酸盐流入对 UASB 的工艺性能干扰风险较低，但对颗粒污泥的物理性质有负面影响。
