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Zheng L, Wu H, Ding A, Tan Q, Wang X, Xing Y, Tian Q, Zhang Y. Optimization of operating parameters and microbiological mechanism of a low C/N wastewater treatment system dominated by iron-dependent autotrophic denitrification. ENVIRONMENTAL RESEARCH 2024; 250:118419. [PMID: 38316389 DOI: 10.1016/j.envres.2024.118419] [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: 11/05/2023] [Revised: 01/26/2024] [Accepted: 02/02/2024] [Indexed: 02/07/2024]
Abstract
Ferrous iron (Fe2+) reduces the amount of external carbon source used for the denitrification of low-C/N wastewater. The effects of key operating parameters on the efficiency of ferrous-dependent autotrophic denitrification (FDAD) and the functioning mechanism of the microbiome can provide a regulatory strategy for improving the denitrification efficiency of low C/N wastewater. In this study, the response surface method (RSM) was used to explore the influence of four important parameters-the molar ratio of Fe2+ to NO3--N (Fe/N), total organic carbon (TOC), the molar ratio of inorganic carbon to NO3--N (IC/N) and sludge volume (SV, %)-on the FDAD efficiency. Functional prediction and molecular ecological networks based on high-throughputs sequencing techniques were used to explore changes in the structure, function, and biomarkers of the sludge microbial community. The results showed that Fe/N and TOC were the main parameters affecting FDAD efficiency. Higher concentrations of TOC and high Fe/N ratios provided more electron donors and improved denitrification efficiency, but weakened the importance of biomarkers (Rhodanobacter, Thermomonas, Comamonas, Thauera, Geothrix and unclassified genus of family Gallionellaceae) in the sludge ecological network. When Fe/N > 4, the denitrification efficiency fluctuated significantly. Functional prediction results indicated that genes that dominated N2O and NO reduction and the genes that dominated Fe2+ transport showed a slight decrease in abundance at high Fe/N levels. In light of these findings, we recommend the following optimization ranges of parameters: Fe/N (3.5-4); TOC/N (0.36-0.42); IC/N (3.5-4); and SV (approximately 35%).
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Affiliation(s)
- Lei Zheng
- College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Haoming Wu
- College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Aizhong Ding
- College of Water Sciences, Beijing Normal University, Beijing, 100875, China; Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education, Beijing, 100875, China.
| | - Qiuyang Tan
- College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Xue Wang
- College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Yuzi Xing
- College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Qi Tian
- College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Yaoxin Zhang
- College of Water Sciences, Beijing Normal University, Beijing, 100875, China
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Lv X, Zhang W, Deng J, Feng S, Zhan H. Pyrite and humus soil-coupled mixotrophic denitrification system for efficient nitrate and phosphate removal. ENVIRONMENTAL RESEARCH 2024; 247:118105. [PMID: 38224940 DOI: 10.1016/j.envres.2024.118105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 12/23/2023] [Accepted: 01/02/2024] [Indexed: 01/17/2024]
Affiliation(s)
- Xin Lv
- Inner Mongolia Research Institute, School of Chemical & Environmental Engineering, China University of Mining & Technology (Beijing), Beijing, 100083, China
| | - Wenxi Zhang
- Inner Mongolia Research Institute, School of Chemical & Environmental Engineering, China University of Mining & Technology (Beijing), Beijing, 100083, China
| | - Jiushuai Deng
- Inner Mongolia Research Institute, School of Chemical & Environmental Engineering, China University of Mining & Technology (Beijing), Beijing, 100083, China; Engineering Technology Research Center for Comprehensive Utilization of Rare Earth, Rare Metal and Rare-Scattered in Non-ferrous Metal Industry, CUMTB, Beijing, 100083, China; Key Laboratory of Separation and Processing of Symbiotic-Associated Mineral Resources in Non-ferrous Metal Industry, CUMTB, Beijing, 100083, China.
| | - Shengyuan Feng
- Jiangxi Gaiya Environm Sci & Technol Co. Ltd, Shangrao, Jiangxi, 334000, China
| | - Hongzhi Zhan
- Jiangxi Gaiya Environm Sci & Technol Co. Ltd, Shangrao, Jiangxi, 334000, China
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