School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, 510006, China.
School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, 510006, China; Hua An Biotech Co., Ltd., Foshan, 528300, China.
J Environ Manage. 2021 Aug 15;292:112762. doi: 10.1016/j.jenvman.2021.112762. Epub 2021 May 19.
For the sake of high efficiency and saving operational cost for high-concentration urea wastewater treatment, a novel two-stage partial nitritation (PN)-anammox process containing simultaneous urea hydrolysis and PN in sequencing batch reactor (SBR) was investigated. Although the influent urea concentration increased from 500 to 1200 mg/L, the SBR simultaneously achieved urea removal efficiency higher than 98% and stable PN with effluent NO-N/NH-N ratio of 1.0-1.3 without any extra alkalinity addition. The intracellular hydrolysis was the dominant mechanism for urea removal and persistent free ammonia inhibition on nitrite-oxidizing bacteria was the main reason for nitrite accumulation of 97.92% in SBR. The subsequent anammox reactor showed efficient nitrogen removal performance with average ammonium removal efficiency, nitrogen removal efficiency and maximum nitrogen removal loading rate of 98.08%, 81.45% and 1.05 kg N·m·d respectively. High-throughput sequencing results indicated Gemmatimonadetes became the most abundant bacterial phylum related to potential intracellular urea hydrolysis and displayed obvious ammonium-oxidizing bacteria enrichment and nitrite-oxidizing bacteria inhibition in SBR, and the dominant anammox bacteria (Candidatus_Kuenenia) in anammox reactor. The proposed process was proven to be promising for high-concentration urea wastewater treatment, facilitating the sustainable development of the urea industry in the future.
为了提高高浓度尿素废水处理的效率和节约运行成本，采用序批式反应器（SBR）中同时含有尿素水解和部分亚硝化（PN）的新型两段式 PN-厌氧氨氧化工艺进行了研究。尽管进水尿素浓度从 500 增加到 1200mg/L，但 SBR 仍同时实现了尿素去除效率高于 98%和稳定的 PN，出水中 NO-N/NH-N 比为 1.0-1.3，无需额外添加碱度。细胞内水解是尿素去除的主要机制，持续的游离氨抑制亚硝酸氧化菌是 SBR 中亚硝酸盐积累达到 97.92%的主要原因。随后的厌氧氨氧化反应器表现出高效的脱氮性能，平均氨去除效率、氮去除效率和最大氮去除负荷率分别为 98.08%、81.45%和 1.05kgN·m·d。高通量测序结果表明，Gemmatimonadetes 成为与潜在细胞内尿素水解相关的最丰富细菌门，并在 SBR 中显示出明显的氨氧化菌富集和亚硝酸盐氧化菌抑制作用，以及厌氧氨氧化反应器中的优势厌氧氨氧化菌（Candidatus_Kuenenia）。该工艺有望用于高浓度尿素废水处理，为未来尿素工业的可持续发展提供了可能。
