Re-Use of Stillage in the Alcohol Production Process

摘要

Waste treatment is an important problem in Thai distilleries. Due to the very high organic matter content, treating stillage so that it meets regulatory discharge limits is difficult. To reduce the amount of stillage, the preliminary studies have been undertaken to use it to replace fresh water in single-cell protein production and in ethanol production. It was found that the maximum percentage of replacement by stillage depends on the initial total concentration of reducing sugar and on the microorganism in the system. In production of single cell protein by Saccharomyces cerevisiae M30 and Candida utilis 6014, substituting stillage for 50-100% of the total fresh water requirements was found to be viable. Laboratory investigation of production of fuel ethanol by Saccharomyces cerevisiae M30 revealed that it is possible to replace 30% of fresh water with stillage.