Glycerol-driven denitratation: process kinetics, microbial ecology, and operational controls

Abstract

Denitratation, the selective reduction of nitrate to nitrite, is a novel process when coupled with anaerobic ammonium oxidation (anammox) could achieve resource-efficient biological nitrogen removal of ammonium- and nitrate-laden waste...

Robustness of partial denitrification-anammox (PdNA) in filters with methanol and glycerol as carbon sources

“…The glycerol PdN efficiency was consistent with previous studies, 21,26,34–38 showing the reproducibility of the PdNA process. The methanol PdN efficiency obtained in this study was higher than the PdN efficiency obtained in the methanol-fed full-scale PdNA filter owing to the higher loading rates in this study (450 g NO 3 − -N m −3 d −1 vs. 110 g NO 3 − -N m −3 d −1 ).…”

“…21 The lower PdN efficiency in the methanol-fed filter was most likely attributed to the difference in electron competition mechanism 33 and lower rate differential between nitrate and nitrite reduction. 18 The glycerol PdN efficiency was consistent with previous studies, 21,26,[34][35][36][37][38] showing the reproducibility of the PdNA process. The methanol PdN efficiency obtained in this study was higher than the PdN efficiency obtained in the methanol-fed full-scale PdNA filter owing to the higher loading rates in this study (450 g NO 3…”

Comparison of carbon sources in a partial denitrification/anammox MBBR using glycerol, acetate, and methanol

“…Several studies have pointed to the Thauera species as a source for this progressive onset concept. 41,47–50…”

“…16,21,22 Studies have shown the ability of glycerol and acetate to induce significant nitrite accumulation. 21,22,34,41 Methanol, acetic acid, and glucose resulted in 17%, 21%, and 23% NO 2 -N accumulation with a low COD/NO 3 -N. 24 In another study, glycerol, acetate, and methanol were all capable of performing PdN, but glycerol and acetate displayed more efficient PdN than methanol and this was attributed to their different electron transport pathways. 16 The sCOD added per TIN removed for each phase was 2.41 ± 0.98, 2.02 ± 0.71, and 1.73 ± 0.81 g COD g N −1 for glycerol, acetate and methanol respectively (Table 2).…”

“…Several studies have pointed to the Thauera species as a source for this progressive onset concept. 41,[47][48][49][50] In two hybrid (suspended growth with granular biomass) PdNA reactors one fed acetate and one fed ethanol (both fed synthetic wastewater) Thauera was the dominant species (61.5% in acetate reactor and 45.2% in ethanol reactor). 15 Anammox bacterial abundance (Candidatus Brocadia and Candidatus Kuenenia) was low at 0.5% for the acetate reactor and 1.0% for the ethanol reactor.…”