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Indexed by:期刊论文

Date of Publication:2021-01-10

Journal:SCIENCE OF THE TOTAL ENVIRONMENT

Volume:746

ISSN No.:0048-9697

Key Words:ZVI; Strengthening effect; DNRA; Desulfovibrio; Nitrogen resources

Abstract:The process of nitrate dissimilation to ammonium(DNRA) is an important way for storing nitrogen in nature and DNRA is a key step in efficient recovery of nitrogen in wastewater. However, in view of the low conversion efficiency of DNRA, zero-valent iron (ZVI) was used to enhance the DNRA process of Desulfovibrio sp. CMX. ZVI can obviously promote the nitrate/nitrite reduction. The experiment indicated that 5 g/L 300 mesh ZVI could convert 5 mmol/L nitrate or nitrite to ammonium in 48 h or 36 h respectively, and the conversion ratio of NO2- to NH4+ could reach more than 90%. The ZVI provided a suitable growth environment for the Desulfovibrio sp. CMX through chemical reduction of nitrite, production of divalent iron (Fe2+), reduction of oxidation-reduction potential (ORP) and adjustment of pH, which strengthened the DNRA performance. This experiment is advantageous for increasing efficiency of DNRA and provides a new idea for efficient recovery of nitrogen resources. (C) 2020 Elsevier B.V. All rights reserved.