Assessment of the influence of thermal pre-treatment time on the macromolecular composition and anaerobic biodegradability of sewage sludge

• Published in: Bioresource technology Vol. 102; no. 2; pp. 660 - 666
• Main Authors: Donoso-Bravo, A., Pérez-Elvira, S., Aymerich, E., Fdz-Polanco, F.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 2011; [New York, NY]: Elsevier Ltd; Elsevier
• Subjects: Anaerobic conditions; Anaerobic digestion; Anaerobiosis; Applied sciences; Assessments; Biodegradability; Biodegradation, Environmental; Biofuels - analysis; Biological and medical sciences; Biological Oxygen Demand Analysis; Biological treatment of sewage sludges and wastes; Biotechnology; Carbohydrates - analysis; Dewatering (separation process); Environment and pollution; Exact sciences and technology; Fatty acids; Filterability; Fundamental and applied biological sciences. Psychology; Hydrolysis; Industrial applications and implications. Economical aspects; Kinetics; Macromolecular Substances - analysis; Methane - analysis; Modeling; Pilot Projects; Pollution; Proteins; Proteins - analysis; Refuse Disposal - methods; Sewage - microbiology; Sewage sludge; Sludge; Solubility; Solubilization; Temperature; Thermal hydrolysis; Time Factors; Wastes; Proteins; Filterability; Thermal hydrolysis; Modeling; Anaerobic digestion; Heat treatment; Biodegradability; Processing time; Sewage sludge; Protein; Hydrolysis; Anaerobe; Macromolecule; Pretreatment
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2010.08.035

Laboratory and pilot-scale experiments were carried out in order to evaluate the influence of thermal pre-treatment time on waste-activated sludge properties and anaerobic biodegradability. Six experimental conditions were analyzed from 0 to 30 min of hydrolysis time. Solubilization of macromolecular compounds, changes in the main sludge properties and anaerobic biodegradability of the sewage sludge were evaluated. A similar carbohydrate solubilization degree was achieved, from 53% to 70% and 59% to 75% for lab- and pilot-scale experiments, respectively. In the case of proteins, the values of solubilization were lower in the pilot-scale experiment than in the laboratory, with 31–45% and 47–70%, respectively. Ammonia and volatile fatty acid did not undergo important changes; however the sludge dewaterability enhanced at increased pre-treatment times. All the pre-treatment conditions had a positive effect with regard to anaerobic biodegradability and by fitting experimental data with a simplified mathematical model, it was concluded that the maximum biogas production rate is more influenced by the pre-treatment time than the total biogas production.