Bioextract production using distillery slop as a carbon source for the anaerobic digestion process

• Published in: Journal of material cycles and waste management 2011-02, Vol.13 (1), p.43-49
• Main Authors: Srisatit, Thares, Chonchanachai, Suphatchaya
• Format: Article
• Language: English
• Subjects: Agriculture; Alcohol; Ambient temperature; Anaerobic digestion; Animal husbandry; Bacteria; Batch reactors; Breeding of animals; Carbon; Carbon sources; Chemical oxygen demand; Civil Engineering; Composite materials; Composting; Composts; Distilleries; Engineering; Environmental Management; Experiments; Fermentation; Organic fertilizers; Original Article; Potassium; Raw materials; Spinach; Spinacia oleracea; Statistical analysis; Syrups & sweeteners; Waste disposal; Waste Management/Waste Technology; Waste materials
• ISSN: 1438-4957; 1611-8227
• DOI: 10.1007/s10163-010-0301-1

Distillery slop is the waste from alcohol manufacture, as from breweries or distilleries, which produce highly organic pollutants. This experiment studied bioextract that used distillery slop instead of molasses as a carbon source for the anaerobic digestion process. In this study, raw materials consisting of water spinach ( Impomoea aquatica ) residual, pineapple ( Ananus comosus ) residual, and fresh fish residual were used in the process to obtain the bioextract. The experiment was divided into three parts: a controlled experiment, mixed carbon sources (molasses and distillery slop), and a single carbon source (only distillery slop). The anaerobic digestibility of the bioextract was evaluated by a batch reactor at ambient temperature for a period of 90 days. The results of this study showed, by observing chemical oxygen demand (COD) at the initial and final processes, that the anaerobic digestive processes have a gradually decreasing rate throughout the fermentation period. The pH of the bioextract decreased at the beginning phase from pH 4 and increased to pH 7 in the last phase during the 90-day period. The results of a test with bean seeds showed compost maturity of over 80% following the organic fertilizer standard requirements of Thailand. With respect to variability, the optimal ratio generating the maximal compost maturity was 1:500 for the bioextract using only molasses as a carbon source and 1:250 for the bioextract using only distillery slop as a carbon source.