Modeling electron competition among nitrogen oxides reduction and N2O accumulation in hydrogenotrophic denitrification. Issue 4 (8th January 2018)

• Record Type: Journal Article
• Authors: Liu, Yiwen; Ngo, Huu H.; Guo, Wenshan; Peng, Lai; Chen, Xueming; Wang, Dongbo; Pan, Yuting; Ni, Bing‐Jie
• Is Part Of: Biotechnology and bioengineering. Volume 115:Issue 4(2018)
• Page Start: 978
• Page End: 988
• Publication Date: 2018-01-08
• Subjects: electron competition -- hydrogenotrophic denitrification -- mathematical modeling -- nitrous oxide; Biotechnology -- Periodicals; Bioengineering -- Periodicals; 660.6
• DOI: 10.1002/bit.26512
• Languages: English
• ISSNs: 0006-3592

Abstract

Abstract: Hydrogenotrophic denitrification is a novel and sustainable process for nitrogen removal, which utilizes hydrogen as electron donor, and carbon dioxide as carbon source. Recent studies have shown that nitrous oxide (N2 O), a highly undesirable intermediate and potent greenhouse gas, can accumulate during this process. In this work, a new mathematical model is developed to describe nitrogen oxides dynamics, especially N2 O, during hydrogenotrophic denitrification for the first time. The model describes electron competition among the four steps of hydrogenotrophic denitrification through decoupling hydrogen oxidation and nitrogen reduction processes using electron carriers, in contrast to the existing models that couple these two processes and also do not consider N2 O accumulation. The developed model satisfactorily describes experimental data on nitrogen oxides dynamics obtained from two independent hydrogenotrophic denitrifying cultures under various hydrogen and nitrogen oxides supplying conditions, suggesting the validity and applicability of the model. The results indicated that N2 O accumulation would not be intensified under hydrogen limiting conditions, due to the higher electron competition capacity of N2 O reduction in comparison to nitrate and nitrite reduction during hydrogenotrophic denitrification. The model is expected to enhance our understanding of the process during hydrogenotrophic denitrification and the ability to predict N2 O accumulation. Abstract : The model describes electron competition during hydrogenotrophic denitrification. The model was validated by two independent hydrogenotrophic denitrifying cultures. Model indicates insignificant N2 O accumulation under hydrogen limiting conditions.