Research progress of nitrate-dependent ferrous oxidation denitrification technology
Nitrate-dependent ferrous oxidation(NDFO)has emerged as a promising autotrophic denitrification technology,effectively addressing key limitations in wastewater treatment,particularly in systems with a low carbon-to-nitrogen(C/N)ratio.NDFO presents substantial economic and environmental advantages,making it an attractive solution for low C/N wastewater treatment.This review critically examines recent advancements in NDFO technology,emphasizing the functional characteristics of various NDFO microorganisms and elucidating the internal reaction mechanisms from both chemical and biological perspectives.We comprehensively analyze the influence of external factors,including temperature,pH,Fe/N ratio,organic carbon sources,and the presence of cations/anions,on the performance of NDFO.Additionally,we explore the role of Fe(Ⅲ)minerals in the NDFO process and discuss strategies to mitigate cell crust formation.Finally,this paper identifies the existing challenges and limitations of NDFO technology and offers strategic directions for future research.