Autotrophic denitrification by sulfur-based immobilized electron donor for enhanced nitrogen removal: Denitrification performance, microbial interspecific interaction and functional traits

Yangyang Tong; Qin Zhang; Zhenghui Li; Guanhua Meng; Baohe Liu; Yongbin Jiang; Susu Li

doi:10.1016/j.biortech.2024.130747

Autotrophic denitrification by sulfur-based immobilized electron donor for enhanced nitrogen removal: Denitrification performance, microbial interspecific interaction and functional traits

Bioresour Technol. 2024 Apr 26:401:130747. doi: 10.1016/j.biortech.2024.130747. Online ahead of print.

Authors

Yangyang Tong¹, Qin Zhang², Zhenghui Li¹, Guanhua Meng³, Baohe Liu², Yongbin Jiang², Susu Li¹

Affiliations

¹ School of Energy and Environment, Anhui University of Technology, Ma'anshan 243002, China.
² School of Energy and Environment, Anhui University of Technology, Ma'anshan 243002, China; Engineering Research Center of Biofilm Water Purification and Utilization Technology of Ministry of Education, Anhui University of Technology, Ma'anshan 243032, China.
³ School of Energy and Environment, Anhui University of Technology, Ma'anshan 243002, China; Engineering Research Center of Biofilm Water Purification and Utilization Technology of Ministry of Education, Anhui University of Technology, Ma'anshan 243032, China. Electronic address: guanhuameng@ahut.edu.cn.

PMID: 38677382
DOI: 10.1016/j.biortech.2024.130747

Abstract

Sulfur-driven autotrophic denitrification (SdAD) is a promising nitrogen removing process, but its applications were generally constrained by conventional electron donors (i.e., thiosulfate (Na₂S₂O₃)) with high valence and limited bioavailability. Herein, an immobilized electron donor by loading elemental sulfur on the surface of polyurethane foam (PFSF) was developed, and its feasibility for SdAD was investigated. The denitrification efficiency of PFSF was 97.3%, higher than that of Na₂S₂O₃ (91.1%). Functional microorganisms (i.e., Thiobacillus and Sulfurimonas) and their metabolic activities (i.e., nir and nor) were substantially enhanced by PFSF. PFSF resulted in the enrichment of sulfate-reducing bacteria, which can reduce sulfate (SO₄^2-). It attenuated the inhibitory effect of SO₄^2-, whereas the generated product (hydrogen sulfide) also served as an electron donor for SdAD. According to the economic evaluation, PFSF exhibited strong market potential. This study proposes an efficient and low-cost immobilized electron donor for SdAD and provides theoretical support to its practical applications.

Keywords: Elemental sulfur filler; Genetic expression level; Microbial community; Microbial inter-species cooperation; Nitrogen removal.