Role of Protein, Amino Acids, and Enzyme Activity on Odor Production from Anaerobically Digested and Dewatered Biosolids

• Published in: Water environment research Vol. 80; no. 2; pp. 127 - 135
• Main Authors: Higgins, Matthew J., Adams, Gregory, Chen, Yen-Chih, Erdal, Zeynep, Forbes, Robert H., Glindemann, Dietmar, Hargreaves, J. Ronald, McEwen, David, Murthy, Sudhir N., Novak, John T., Witherspoon, Jay
• Format: Journal Article
• Language: English
• Published: Alexandria, VA Water Environment Federation 01.02.2008; Blackwell Publishing Ltd
• Subjects: Amino acids; Amino Acids, Sulfur - analysis; Amino Acids, Sulfur - metabolism; anaerobic digestion; Anaerobiosis; Applied sciences; Bacteria, Anaerobic; Bioavailability; Biological and medical sciences; biosolids; Biotechnology; Biotransformation; Bottles; Centrifugation; Chemicals; Dewatering; Enzyme activity; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General purification processes; Iron; Methods; Methods. Procedures. Technologies; odor; Odorants - analysis; Odors; Other industrial wastes. Sewage sludge; Others; Pollution; protein; Proteins - analysis; Proteins - metabolism; RESEARCH PAPERS; Sewage - chemistry; Sewerage works: sewers, sewage treatment plants, outfalls; Sludge digestion; Solids; Sulfides; Various methods and equipments; volatile sulfur compounds; Volatilization; Waste Disposal, Fluid - methods; Wastes; Wastewaters; Water Purification - methods; Water treatment and pollution; North America; Olfactometry; Waste treatment; Sewage sludge; Anaerobic digestion; Sewage treatment plant; Gas chromatography; Storage; Bottle; Production; Detection threshold; Headspace; Biological treatment; Odor
• ISSN: 1061-4303; 1554-7531
• DOI: 10.2175/106143007X220716

The main objective of this research was to test the hypothesis that bioavailable protein and, more specifically, the sulfur-containing amino acids within the protein, can be degraded by proteolytic enzymes to produce odor-causing compounds—mainly volatile sulfur compounds (VSCs)—during biosolids storage. To achieve these objectives, samples of digester effluent and cake solids were collected at 11 different wastewater treatment plants in North America, and the samples were analyzed for protein and amino acid content and general protein-degrading enzyme activity. At the same time, cake samples were stored using headspace bottles, the concentration of VSCs were measured using gas chromatography, and olfactometry measurements were made by a trained odor panel. The results showed that the bound cake protein content and methionine content was well-correlated with VSC production and the detection threshold measured by the odor panel.