Research progress of autotrophic denitrification technology of sulfur, iron and sulfur-iron based electron donors

Abstract

Autotrophic denitrification technology has the advantages of no additional carbon source, low sludge yield and low cost. It is one of the promising technologies for deep denitrification of low C/N wastewater under the dual-carbon background. The selection of inorganic electron donor is the key to its wide practical application. According to the principle of denitrification, sulfur autotrophic denitrification is easy to produce acid and sulfate, iron denitrification consumes acid and accumulates nitrite, whereas sulfur-iron coupling autotrophic denitrification can combine the characteristics of both to maintain stable reaction pH and reduce secondary pollution. In this paper, the principle and characteristics of autotrophic denitrification based on sulfur, iron and sulfur-iron as electron donors were analyzed, and the dominant bacteria under different electron donors were introduced. It was hoped to provide reference for improving nitrogen removal efficiency and reducing secondary pollution by sulfur based, iron based and sulfur-iron coupled autotrophic denitrification technologies.

Keywords

• sulfur-iron based
• electron donor
• autotrophic denitrification
• denitrification