Enrichment of Autotrophic Denitrifiers From Anaerobic Sludge Using Sulfurous Electron Donors

Abstract

Graphical Abstract

Applications of Up-Flow Anaerobic Sludge Blanket (UASB) and Characteristics of Its Microbial Community: A Review of Bibliometric Trend and Recent Findings

“…Denitrification in UASB sludge and the influence of microbial community were also studied by Carboni et al [ 105 ]. Adding electron donors (such as sulfur, pyrite, thiosulfate, and sulfide), the microbial community diversity significantly reduced and only several genera of autotrophic denitrifiers (such as Thiobacillus , Thioprofundum , and Ignavibacterium ) were selected and therefore becoming dominant as reported by [ 105 ].…”

“…Denitrification in UASB sludge and the influence of microbial community were also studied by Carboni et al [ 105 ]. Adding electron donors (such as sulfur, pyrite, thiosulfate, and sulfide), the microbial community diversity significantly reduced and only several genera of autotrophic denitrifiers (such as Thiobacillus , Thioprofundum , and Ignavibacterium ) were selected and therefore becoming dominant as reported by [ 105 ]. Zhang et al [ 106 ] found that mixotrophic conditions can inhibit the denitrification in the anammox system but at the same time can enhance the ability of Candidatus Kuenenia to use diverse types of carbon sources.…”

Autotrophic Denitrification of Nitrate Rich Wastewater in Fluidized Bed Reactors Using Pyrite and Elemental Sulfur as Electron Donors

“…Sulfur (SR) and pyrite (PR) fluidized bed reactors were respectively inoculated with sulfur and pyrite oxidizing denitrifying cultures, which were enriched as described previously (Carboni et al, 2021). Sterile anoxic basal medium used during the enrichment process was prepared as described by Stams et al (1993) comprising of (g/L): 1.2 KNO 3 ; 0.41…”

“…This behavior makes them suitable, slow-release electron donors for autotrophic denitrification. Preliminary experiments with pyrite showed several advantages such as the preservation of a stable pH without the addition of any base addition (Hu et al, 2020) and low sulfate production (Di Capua et al, 2020;Carboni et al, 2021), however its application might lead to lower nitrogen removal rates compared with S 0 -driven denitrification (Liu et al, 2021). Therefore, further studies on pyritedriven autotrophic denitrification are of great interest, mainly aiming at increasing denitrification rates in continuous-flow bioreactors.…”

“…In previous research no systematic study has been carried out that comparatively investigated the differences and evaluated the advantages and drawbacks of the two electron donors (pyrite and elemental sulfur). The present study explored the performance of two fluidized bed reactors (FBRs) with either pyrite (FeS 2 ) or elemental sulfur (S 0 ) as electron donor for which autotrophic denitrification occurs according to the following reactions (Carboni et al, 2021):…”