Enhancement of Chemical-Oxygen Demand and Color Removal of Distillery Spent-Wash by Ozonation

• Published in: Water environment research Vol. 78; no. 4; pp. 409 - 420
• Main Authors: Srivastava, S., Bose, P., Tare, V.
• Format: Journal Article
• Language: English
• Published: Alexandria, VA Water Environment Federation 01.04.2006; Blackwell Publishing Ltd
• Subjects: aerobic treatment; Aerobiosis; Alcohols - chemistry; anaerobic treatment; Anaerobiosis; Applied sciences; Biochemical oxygen demand; Biodegradability; Biodegradation; Biodegradation, Environmental; Bioreactors; Carbon; Chemical oxygen demand; Color removal; Coloring Agents - chemistry; Distilleries; Distillery effluents; distillery spent‐wash; enhancement of biodegradability; Exact sciences and technology; Food-Processing Industry - methods; Industrial wastewaters; Organic chemicals; Oxidation; Oxidation-Reduction; ozonation; Ozone; Ozone - metabolism; Pollution; Research Papers; Waste Disposal, Fluid - methods; Wastewater; Wastewater treatment; Wastewaters; Water Pollutants - analysis; Water Pollutants, Chemical - analysis; Water Purification; Water treatment; Water treatment and pollution; Biodegradation; Discoloration; Ozone; Aerobe; Chemical degradation; Biological purification; Ozonization; Anaerobe; Chemical oxygen demand; Industrial waste water; Food industry; Distillery; Water quality; Physicochemical purification; Total organic carbon; Waste water purification
• ISSN: 1061-4303; 1554-7531
• DOI: 10.2175/106143005X90100

Distillery spent-wash has very high organic content (75 000 to 125 000 mg/L chemical-oxygen demand [COD]), color, and contains difficult-to-biodegrade organic compounds. For example, anaerobic treatment of the distillery spent-wash used in this study resulted in 60% COD reduction and low color removal. Subsequent aerobic treatment of the anaerobic effluent resulted in enhancement of COD removal to 66%. In this paper, the effect of ozonation on various properties of the anaerobically treated distillery effluent, including the effect on its subsequent aerobic biodegradation, was investigated. Ozonation of the anaerobically treated distillery effluent at various ozone doses resulted in the reduction of total-organic carbon (TOC), COD, COD/TOC ratio, absorbance, color, and increase in the biochemical-oxygen demand (BOD)/COD ratio of the effluent. Further, ozonation of the anaerobically treated distillery effluent at an ozone dose of 2.08 mg/mg initial TOC and subsequent aerobic biodegradation resulted in 87.4% COD removal, as compared to 66% removal when ozonation was not used.