Asano Kenya, Watari Takahiro, Hatamoto Masashi, Yamaguchi Takashi
Department of Civil and Environmental Engineering, National Institute of Technology, Nagano College, Nagano, Japan.
Department of Civil and Environmental Engineering, Nagaoka University of Technology, Niigata, Japan.
Environ Technol. 2021 Jun 20:1-10. doi: 10.1080/09593330.2021.1938242.
Tofu is widely processed in East and Southeast Asian countries. During the production, highly polluted wastewater is discharged. This wastewater is commonly treated using a high-rate anaerobic wastewater treatment process; however, several organic compounds and nitrogen remain in the anaerobic effluent. The aim of this study was to develop a combined upflow anaerobic sludge blanket (UASB) and downflow hanging sponge (DHS) biosystem that that serves as a post-treatment for an expanded granular sludge blanket reactor used for treating tofu-processing wastewater in Japan for 699 days. The UASB reactor played a role in treating of COD, with 58 ± 16% and 74 ± 20% of total COD and soluble COD removed anaerobically. Besides, methane was recovered from removed soluble COD were 63 ± 28% and 87 ± 64% at winter and summer. Meanwhile, the DHS reactor showed its potential in treatment of BOD and TSS. The final effluents were recorded as 67 ± 38 mg L, 50 ± 26 mg L, and 22 ± 16 mg L of total COD, BOD and total suspended solids, respectively. This indicates that the proposed UASB-DHS system has proven its suitability as post-treatment system for anaerobically treated tofu-processing wastewater.
豆腐在东亚和东南亚国家被广泛加工。在生产过程中，会排放高污染废水。这种废水通常采用高速厌氧废水处理工艺进行处理；然而，厌氧流出物中仍残留有几种有机化合物和氮。本研究的目的是开发一种上流式厌氧污泥床（UASB）和下流式悬挂海绵（DHS）组合生物系统，作为日本用于处理豆腐加工废水的膨胀颗粒污泥床反应器的后处理系统，运行了699天。UASB反应器在处理化学需氧量（COD）方面发挥了作用，厌氧去除了总COD的58±16%和可溶性COD的74±20%。此外，从去除的可溶性COD中回收的甲烷在冬季和夏季分别为63±28%和87±64%。同时，DHS反应器在处理生化需氧量（BOD）和总悬浮固体（TSS）方面显示出潜力。最终出水的总COD、BOD和总悬浮固体分别记录为67±38mg/L、50±26mg/L和22±16mg/L。这表明所提出的UASB - DHS系统已证明其作为厌氧处理豆腐加工废水后处理系统的适用性。
