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Bian Y, Fu K, Xu R, Guan T, Huo A, Zhang R, Li X, Qiu F, Zhang Y. Achieving partial nitrification and denitrification coupled with simultaneous partial nitrification, anammox, and denitrification (PND-SNAD) by the inhibition of sulfide to accomplish stabilized nitrogen removal. ENVIRONMENTAL RESEARCH 2025; 278:121630. [PMID: 40274089 DOI: 10.1016/j.envres.2025.121630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2025] [Revised: 04/14/2025] [Accepted: 04/15/2025] [Indexed: 04/26/2025]
Abstract
The simultaneous partial nitrification, anammox, and denitrification (SNAD) process is widely applied for treating high-ammonia wastewater, but its application to low-ammonia organic wastewater has been scarcely explored. In this study, a partial nitrification and denitrification coupled with simultaneous partial nitrification, anammox, and denitrification (PND-SNAD) system was established to treat organic wastewater with low ammonia concentration. Experimental results revealed that sulfide at 5 mg/L selectively inhibited nitrite-oxidizing bacteria (NOB) but had little effect on ammonium-oxidizing bacteria (AOB). Finally, NOB was suppressed in PND system by intermittently adding sulfide to the PND system. The PND system provided nitrite and activated sludge enriched with AOB to the SNAD system during stable operation. The SNAD system demonstrated chemical oxygen demand (COD) and nitrogen removal efficiencies of 89.86 % and 86.45 %. Candidatus Brocadia and Nitrosomonas were the main ammonium oxidizing bacteria (AnAOB) and AOB. The contribution of AOB and denitrifying bacteria (DNB) to nitrogen transformation was 67.15 % and 25.33 % in the PND system. In the SNAD system, the contributions of AnAOB, AOB, and DNB were 34.40 %, 33.59 %, and 27.56 %, respectively. Overall, this study provided a new sustainable strategy for treating organic wastewater with low ammonia concentration.
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Affiliation(s)
- Yihao Bian
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China; Key Laboratory of Urban Storm Water System and Water Environment Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Kunming Fu
- Key Laboratory of Urban Storm Water System and Water Environment Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China.
| | - Ruotong Xu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China
| | - Teng Guan
- Key Laboratory of Urban Storm Water System and Water Environment Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Aotong Huo
- Key Laboratory of Urban Storm Water System and Water Environment Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Ruibao Zhang
- Key Laboratory of Urban Storm Water System and Water Environment Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Xueqin Li
- Key Laboratory of Urban Storm Water System and Water Environment Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Fuguo Qiu
- Key Laboratory of Urban Storm Water System and Water Environment Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Yongji Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China
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Wen Q, Wang Z, Liu B, Liu S, Huang H, Chen Z. Enrichment performance and salt tolerance of polyhydroxyalkanoates (PHAs) producing mixed cultures under different saline environments. ENVIRONMENTAL RESEARCH 2024; 251:118722. [PMID: 38499223 DOI: 10.1016/j.envres.2024.118722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Revised: 03/08/2024] [Accepted: 03/12/2024] [Indexed: 03/20/2024]
Abstract
The key to the resource recycling of saline wastes in form of polyhydroxyalkanoates (PHA) is to enrich mixed cultures with salt tolerance and PHA synthesis ability. However, the comparison of saline sludge from different sources and the salt tolerance mechanisms of salt-tolerant PHA producers need to be clarified. In this study, three kinds of activated sludge from different salinity environments were selected as the inoculum to enrich salt-tolerant PHA producers under aerobic dynamic feeding (ADF) mode with butyric acid dominated mixed volatile fatty acid as the substrate. The maximum PHA content (PHAm) reached 0.62 ± 0.01, 0.62 ± 0.02, and 0.55 ± 0.03 g PHA/g VSS at salinity of 0.5%, 0.8%, and 1.8%, respectively. Microbial community analysis indicated that Thauera, Paracoccus, and Prosthecobacter were dominant salt-tolerant PHA producers at low salinity, Thauera, NS9_marine, and SM1A02 were dominant salt-tolerant PHA producers at high salinity. High salinity and ADF mode had synergistic effects on selection and enrichment of salt-tolerant PHA producers. Combined correlation network with redundancy analysis indicated that trehalose synthesis genes and betaine related genes had positive correlation with PHAm, while extracellular polymeric substances (EPS) content had negative correlation with PHAm. The compatible solutes accumulation and EPS secretion were the main salt tolerance mechanisms of the PHA producers. Therefore, adding compatible solutes is an effective strategy to improve PHA synthesis in saline environment.
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Affiliation(s)
- Qinxue Wen
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin, 150090, China; School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Zifan Wang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin, 150090, China; School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Baozhen Liu
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, China
| | - Shaojiao Liu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin, 150090, China; School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou, 510006, China
| | - Haolong Huang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin, 150090, China; School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Zhiqiang Chen
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin, 150090, China; School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
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