Reported values for growth kinetic parameters show an order in competitivity of heterotrophic sulfate reducing bacteria>methanogens>homoacetogens for the substrate hydrogen. This order suggests that methanogens can succesfully compete with consortia of heterotrophic SRB and homoacetogens when H2/CO2 is present as sole substrate. However, we found in experiments using gas-lift reactors inoculated with anaerobic sludge and fed with H2/CO2 and sulfate, that heterotrophic sulfate reduction rapidly and completely outcompeted methanogenesis, whereas a low amount of acetate was formed. Thus, in disagreement with the above competitivity order, hydrogen is more readily consumed by homoacetogenesis than by methanogenesis, indicating that the competition is not kinetically determined. The superior settling velocity of sulfidogenic-acetogenic sludge compared to that of methanogenic sludge suggests that the former sludge is better retained, which can explain the predominance of sulfate reduction/homoacetogenesis over methanogenesis.
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Water Res
January 2025
Department of Civil and Environmental Engineering, University of Florence, Via di S. Marta, 3, 50139, Firenze, Italy.
The performance of Upflow Anaerobic Sludge Blanket (UASB) bioreactors treating sulfate (SO) -rich effluents depends on multiple factors, including microbial interactions and operational conditions. The high complexity of these systems necessitates the use of mathematical modelling tools to better understand the process and predict the long-term impacts of various operational variables. In this work, a mathematical model describing the long-term operation of a sulfate-fed 2.
View Article and Find Full Text PDFEnviron Res
January 2025
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. Electronic address:
The hydrogen-based partial denitrification coupled with anammox (H-PDA) biofilm system effectively achieves low-carbon and high-efficiency biological nitrogen removal. However, the effects and biological interaction mechanism of H flux with the H-PDA system have not yet been understood. This study assessed the effects of H flux on interactions among anammox bacteria (AnAOB), denitrifying bacteria (DB), and sulfate-reducing bacteria (SRB) coexisting in a H-PDA system.
View Article and Find Full Text PDFJ Hazard Mater
December 2024
School of Civil Engineering and Architecture, Taizhou University, Taizhou 318000, China. Electronic address:
The removal of selenite (Se(IV)) and cadmium (Cd(II)) from low-carbon wastewater presents significant challenges. However, the addition of external organic carbon sources is limited in application due to the high cost and potential for secondary pollution. This study introduced a "hibernation-like microbial survival strategy", enabling efficient removal of Se(IV) and Cd(II) in sulfur autotrophic reactor, with S acting as the electron donor.
View Article and Find Full Text PDFBioresour Technol
February 2025
National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China.
A novel mixotrophic denitrification biofilter for nitrate removal using polycaprolactone and thiosulfate (MD-PT) as electron donors was investigated. MD-PT achieved high nitrate removal efficiency of approximately 99.8 %.
View Article and Find Full Text PDFSyst Appl Microbiol
November 2024
Winogradsky Institute of Microbiology, Federal Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia.
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