Anaerobic digestion of biorefinery lignin: Effect of different wet explosion pretreatment conditions. (February 2020)

• Record Type: Journal Article
• Authors: Usman Khan, Muhammad; Kiaer Ahring, Birgitte
• Is Part Of: Bioresource technology. Volume 298(2020)
• Publication Date: 2020-02
• Subjects: Biorefinery lignin -- Anaerobic digestion -- Lignin degradation -- Pretreatment; 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.2019.122537
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Wet explosion pretreatment of biorefinery lignin. Increased methoxylation of lignin increased lignin degradation. The addition of NaOH and O2 increased lignin degradation. A total of 56.3% lignin was converted in to methane. Abstract: This study examine ways to make biorefinery lignin accessible for anaerobic digestion. The raw material was the residue after removing carbohydrates by Wet Explosion pretreatment at 190 °C and 7.5% O2 followed by enzymatic hydrolysis. The residual solid was mainly composed of lignin and was the raw material for a second WEx pretreatment operated at 220 °C with 4% oxygen and variable concentrations of NaOH (0–2%). Lignin B was the residue after pretreated without NaOH, Lignin C was pretreated at 1% NaOH, and Lignin E at 2% NaOH. Anaerobic digestion was carried out on all lignin fractions (Lignin A, B, C and E) at thermophilic conditions (52 °C) by mixing 70% of each lignin fractions with 30% clarified manure. The results showed that the lignin samples were demethoxylated as part of the biodegradation and that the highest severity pretreatment (with oxygen and 2% NaOH) resulted in the highest methane yield.