Production of ethyl alcohol from molasses using continuous process

Abstract

Sugar cane molasses from Nigerian Sugar processing factory Bacita were used for ethanol production. A  special ethanol resistant yeast strain Saccharomyces cerevisiae (DIST/IPF/90) employed as inoculum was propagated on clarified molasses. Fermentation of clarified molasses to ethanol was brought about at room  temperature (27°C) in a three stage continuous process using the chemostat system of operation. The highest ethanol yield of 10.5% was obtained in the third stage of the fermentation cascade at the flow rate of 33ml/hr with a retention time of 30hr in each tank. The first and second stages of the process had alcohol yields of  4.4% and 6.3% respectively as their maximum. The pH of the fermenting medium maintained at 4.5 using sulphuric acid was foWld to be inhibitory to contaminants. The result obtained from this study shows that  ethanol yield in continuous process increase with increase in the number of tanks.