Hydrothermal carbonization of industrial mixed sludge from a pulp and paper mill. (January 2016)

• Record Type: Journal Article
• Authors: Mäkelä, Mikko; Benavente, Verónica; Fullana, Andrés
• Is Part Of: Bioresource technology. Volume 200(2016)
• Page Start: 444
• Page End: 450
• Publication Date: 2016-01
• Subjects: Biosolids -- Hydrothermal treatment -- Sludge treatment -- Wet torrefaction -- Waste biomass; 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.2015.10.062
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: Sludge carbonization governed by dehydration, depolymerization and decarboxylation. Additive type significant for hydrochar carbon content and carbon and energy yield. 97–147% of the theoretical energy requirement potentially attainable from hydrochar. Dissolved organic components can be treated by conventional biological methods. Abstract: Mixed sludge from a pulp and paper mill was hydrothermally carbonized at 180–260 °C for 0.5–5 h with the use of HCl or NaOH for determining the effect of acid and base additions during sludge carbonization. Based on the results carbonization was mainly governed by dehydration, depolymerization and decarboxylation of sludge components. Additive type had a statistically significant effect on hydrochar carbon content and carbon and energy yield, of which especially energy yield increased through the use of HCl. The theoretical energy efficiencies of carbonization increased with decreasing reaction temperature, retention time and the use of HCl and suggested that the energy requirement could be covered by the energy content of attained hydrochar. The BOD5 /COD-ratios of analyzed liquid samples indicated that the dissolved organic components could be treated by conventional biological methods.