Bioethanol production from sorghum grains

Abstract

A biofuel is a fuel that produced through contemporary biological processes such as agriculture and anaerobic digestion, rather than a fuel produced by geological processes. It can be derived directly from plants or indirectly from agriculture or industrial waste. Bioethanol is an alcohol made by fermentation, it is produced from sugar or starch crops such as corn, sugar cane or sweet sorghum. Biodiesel and ethanol can be used as fuel for vehicles in its pure form but it is usually used as gasoline additive. Sorghum is a fast- growing crop that can be harvested twice a year and that can produce both food (grain) and energy. In this study, sorghum juice, which mostly consists of readily fermentable sugars, were converted to bio-ethanol. Ethanol is a renewable source of energy and it is potentially cleaner alternative to fossil fuels. Production of ethanol is growing day by day at a great extent for its versatile application and demand. Fermentation is a biological process in which sugars are converted to cellular energy then produce ethanol. The objective of this study is to enhance the production of ethanol from sorghum using fermentation and simple distillation. An amount of grain sorghum flour was mixed with water, and yeast was added and the fermentation was conducted for different periods of time at room temperature and at closed container with small pipe for CO2 removal. The results showed that (69%v/v) ethanol could be obtained from sorghum at specific conditions. The fermented liquid was filtered and introduce to simple distillation device to obtain ethanol. The ethanol was collected and its concentration was measured by refractometer. The design of a distillation column was done where the minimum number of stages were 18 and actual number of stages were 35 with a reflux ratio of 12.6, column diameter 2.5m and hight 22m , in a sieve tray column