Characterization and prediction of organic nitrogen biodegradability during anaerobic digestion: A bioaccessibility approach. (September 2018)

• Record Type: Journal Article
• Authors: Bareha, Y.; Girault, R.; Jimenez, J.; Trémier, A.
• Is Part Of: Bioresource technology. Volume 263(2018)
• Page Start: 425
• Page End: 436
• Publication Date: 2018-09
• Subjects: Anaerobic digestion -- Nitrogen -- Ammonium -- Biodegradability -- Bioaccessibility; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2018.04.085
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: Organic nitrogen is contained in materials with various bioaccessibility levels. Organic nitrogen bioaccessibility differs from organic carbon bioaccessibility. Organic nitrogen biodegradability cannot be estimated from carbon biodegradability. Van Soest fractionation does not predict organic nitrogen biodegradability. Models using bioaccessibility data from EPS fractionation show good predictability. Abstract: Prediction of organic nitrogen mineralization into ammonium during anaerobic digestion is required for optimizing substitution of mineral fertilizer by digestates. The aim of this study was to understand organic nitrogen biodegradability and to investigate how it can be predicted from carbon biodegradability, and nitrogen bioaccessibility, respectively. Bioaccessibility was assessed using fractionation methods based on sequential extractions. Results showed that organic nitrogen was present in fractions whose bioaccessibility levels differed. Organic nitrogen and carbon biodegradability were also determined and compared. Results highlighted two groups of substrates: the first with an initial NH4 + /TKN < 30%, whose carbon and nitrogen biodegradability are similar; the second with an initial NH4 + /TKN > 30%, whose carbon and nitrogen biodegradability differ significantly. To enable prediction on all substrates, partial least square (PLS) regressions were carried out to link organic nitrogen bioaccessibility indicators to biodegradability. The models successfully predicted organic nitrogen biodegradability with a maximum prediction error of 10%.