Sulfur-based mixotrophic partial denitrication: performance, microorganisms and mechanisms (PRJCA028262)
The main factor limiting the application and promotion of anaerobic ammonium oxidation process is the lack of sufficient nitrite accumulation in wastewater. Partial denitrification can provide stable nitrite accumulation, and its coupling with anaerobic ammonium oxidation has great application prospects. So far, there have been few studies on the coupling of two-stage mixed nutrient partial denitrification and anaerobic ammonium oxidation, and their process principles and applications are not yet mature. Therefore, we constructed a mixotrophic partial denitrification system based on fully domesticated heterotrophic partial denitrification sludge by providing sulfides, and operated continuously for 387 days. With regulating the partial denitrification of sulfur-based mixotrophic partial denitrification, the appropriate ratio of heterotrophic/autotrophic electron donors was found to further explore the microbial community structure and analyze the competitive and synergistic relationship between autotrophic and heterotrophic microorganisms. This study proposes a mixotrophic partial denitrification based on sulfides and organic matter, and enriches the theoretical basis of mixotrophic partial denitrification, aiming to provide reference and theoretical guidance for the coupling of mixotrophic partial denitrification and anaerobic ammonium oxidation in a two-stage approach.