This study evaluated the interactive effect of Cu(II) and Zn(II) on anaerobic ammonium oxidation (anammox) activity using response surface methodology with a central composite design. A regression model equation was developed and validated to predict the normalized anammox activity (NAA) of anammox granules exposed to various heavy metal concentrations. The joint inhibitory effect tended to exacerbate initially and reversed as the concentrations increased and then moderated again. The most severe inhibition, resulting in a NAA of 20.1%, occurred at Cu(II) and Zn(II) concentrations of 16.3 and 20.0mgL(-1), respectively. Notably, the cumulative toxicity was mitigated with the aid of intermittent exposure acclimatization. Additionally, pre-exposure to Cu(II) in the absence of substrates strongly inhibited anammox activity. However, the presence of NO2(-) significantly enhanced Cu(II) inhibition. Therefore, such conditions should be avoided to minimize the disturbance of the anammox process.
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http://dx.doi.org/10.1016/j.biortech.2015.10.035 | DOI Listing |
Chemosphere
January 2025
Biological Processes Laboratory (LPB), São Carlos School of Engineering (EESC), University of São Paulo (USP), Av. João Dagnone, 1100, Santa Angelina, São Carlos, São Paulo, 13563-120, Brazil.
Simultaneous partial nitrification, anammox, and denitrification (SNAD) process offers a promising method for the effective removal of carbon and nitrogen from wastewater. However, ensuring stability is a challenge. This study investigated operational parameters such as hydraulic retention time (HRT) and biomass retention to stabilize SNAD operation, transitioning from synthetic to anaerobically pre-treated municipal wastewater (APMW) in an upflow hybrid biofilm-granular reactor (UHR).
View Article and Find Full Text PDFBioresour Technol
January 2025
School of Environmental Engineering, Henan University of Technology, Zhengzhou 450001, China; Zhengzhou Key Laboratory of Water Safety and Water Ecology Technology, Zhengzhou 450001, China; Henan International Joint Laboratory of Environmental Pollution Remediation and Grain Quality Security, Zhengzhou 450001, China.
This study integrates partial denitrification/Anammox (PD/A) with hydroxyapatite (HAP) crystallization in a single reactor, achieving simultaneous nitrogen and phosphorus removal along with phosphorus recovery. By adjusting pH, sludge concentration, low COD/TN ratio, and applying moderate dissolved oxygen stress, the system operated stably and promoted the synergistic growth of HAP and biomass. Results showed a nitrogen removal efficiency (NRE) of 94.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
School of Civil Engineering and Architecture, Zhejiang University of Science and Technology, Hangzhou, Zhejiang 310023, China; Zhejiang-Singapore Joint Laboratory for Urban Renewal and Future City, Hangzhou 310023, China. Electronic address:
Despite growing attention to the environmental pollution caused by tire wear particles (TWPs), the effects of pristine and photoaged TWPs (P-TWPs and A-TWPs) and their TWP leachates (TWPLs; P-TWPL and A-TWPL) on key nitrogen removal processes in estuarine sediments remain unclear. This study explores the responses of the denitrification rate, anammox rate, and nitrous oxide (NO) accumulation to P-TWP, A-TWP, P-TWPL, and A-TWPL exposure in estuarine sediments, and assesses the potential biotoxic substances present in TWPLs. P-TWPs reduced the denitrification rate by 17.
View Article and Find Full Text PDFEnviron Res
January 2025
Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100123, China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.
Stable inhibition of nitrite-oxidizing bacteria (NOB) is a significant challenge in achieving partial nitrification (PN) and partial nitrification-anaerobic ammonia oxidation (PNA). Growing evidence suggested that NOB can develop resistance to suppression over time, leading to the re-enrichment of NOB within reactors. To address these issues, this study aimed to achieve stable PN by regulating SRT to selectively washout NOB during the lag phase of activity recovery following FA/FNA exposure.
View Article and Find Full Text PDFBioresour Technol
January 2025
School of Engineering, Hangzhou Normal University, Hangzhou 310018 China.
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