%0 Journal Article
%T Iron-based mixotrophic denitrification for enhancing nitrate removal from municipal secondary effluent: Performance, microbial community dynamics, and economic feasibility.
%A Wang P
%A He Y
%A Zhou G
%J Bioresour Technol
%V 406
%N 0
%D 2024 Aug 15
%M 38885725
%F 11.889
%R 10.1016/j.biortech.2024.130989
%X High nitrate content limits the recycling of the secondary effluent of wastewater treatment plants. In the research, one biomass-iron mixture (BIM) filter material based on mixotrophic denitrification mode (heterotrophic and iron-driven autotrophic denitrification) was developed and used to construct a novel denitrification biological filter (BIM-DNBF) for the nitrogen removal of secondary effluent. BIM-DNBF had a short start-up time (approximately 9 days), and high total nitrogen removal (81 %-89 %) without external addition of organic carbon sources during the whole operation. The coexistence of dominant heterotrophic-denitrification-like Pseudomonas and Erysipelothrix as well as iron-driven autotrophic-denitrification-like Citrobacter, Acidovorax, etc. were found in the BIM-DNBF. Moreover, biomass was recognized as one key player in promoting the reduction of Fe3+ to Fe2+, thereby facilitating the occurrence of iron-driven autotrophic denitrification. In addition, BIM-DNBF was assessed to be affordable. These findings provide evidence that BIM-DNBF can be an efficient technology for nitrogen removal of secondary effluent.