Nitrogen Removal Characteristics of the Highly Efficient Heterotrophic Nitrification-Aerobic Denitrification Bacterium Hy-1 and Practical Application in Biological Deodorization

Abstract

A heterotrophic nitrifying aerobic denitrifying (HN-AD) strain HY-1 with excellent capacity, identified as Paracoccus denitrificans, was capable to remove individual NH4+, NO2-, and NO3- with denitrification rate of 17.33 mg·L-1·h-1, 21.83 mg·L-1·h-1, and 32.37 mg·L-1·h-1, and also execute denitrify function under anaerobic conditions with a rate of 14.56 mg·L-1·h-1. HY-1 required less energy investment, which exhibited average denitrification rate of 5.19 mg·L-1·h-1 at C/N ratio (C/N=1). After nitrification-denitrification metabolic pathway analysis, HY-1 was applied in a biological trickling filter reactor (BTF) for compost deodorization. The results showed that adding of HY-1 greatly reduced the ionic concentration of NH4+ and NO3- in the circulating liquid without impairing the deodorization effect (NH3 removal rate＞98.07%). To our knowledge, the property of HY-1 was superior to the other reported HN-AD strains. During the first application of HN-AD strain in bio-deodorization, HY-1 enhanced the performance of BTF reactor and significantly reduced the secondary pollution.

Keywords: Anaerobic denitrification, Biotrickling filter (BTF), Deodorization, Heterotrophic nitrification Aerobic denitrification, HN-AD pathway.