We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
An efficient method of nitrate-nitrogen removal from wastewater based on pyrrhotite autotrophic denitrification.
- Authors
Ting Liu; Changsheng Zhao; Qingfeng Chen; Luzhen Li; Lei Li; Guorui Si; Beibei Guo
- Abstract
Wastewater treatment plant is the primary source of nitrogen discharge. Some studies have shown excessive nitrate-nitrogen concentration as the main reason for excessive total nitrogen discharge in China. To solve this problem from the sewage treatment plant, autotrophic denitrifying bacteria were added to the simulation device equipped with pyrrhotite to remove nitrate-nitrogen from wastewater. The purified strains were inoculated into the simulated wastewater. When the ratio of pyrrhotite to quartz sand was 1:1 and the influent NO3--N concentration was 30.0 mg/L, the removal effects of NO3--N and total nitrogen were the best, and the removal rates were 95.9% and 71.9%, respectively. Meanwhile, sulfate in the system gradually accumulated, up to 233 mg/L. To further study the removal mechanism of nitrate-nitrogen in the autotrophic denitrification process, the evolution of microbial community in the purified strain was studied by 16S rDNA sequencing. The sequencing results showed that the dominant bacteria was the genus Sulfurimonas, with an abundance of 66.6%, which was increased by more than 40.0% compared with some studies. This method improves the removal rate of nitrate-nitrogen and makes the total nitrogen in effluent meet the sewage discharge standard (15.0 mg/L). The results showed that autotrophic denitrifying bacteria can be screened and purified with thiosulfate as the substrate, and most of the NO3--N can be reduced to N2 using pyrrhotite as an electron donor, while successfully converting nitrate-nitrogen into N2 and realizing the complete removal of nitrogen from wastewater. Meanwhile, autotrophic denitrification does not need additional carbon sources, which greatly reduces operational energy consumption. This study provides an efficient and low-energy nitrate-nitrogen removal method and provides a theoretical basis for removing nitrate-nitrogen in wastewater lacking organic matter.
- Subjects
CHINA; PYRRHOTITE; SEWAGE disposal plants; SEWAGE; DENITRIFICATION; AUTOTROPHIC bacteria; NITROGEN removal (Water purification)
- Publication
Desalination & Water Treatment, 2022, Vol 262, p100
- ISSN
1944-3994
- Publication type
Article
- DOI
10.5004/dwt.2022.28555