Saturday, July 20, 2019
Alcohol Producing Yeast :: Environment, Fossil Fuel, Crude Oil
Food and energy security have always been essential needs in various ways. This is due to their limited resources and their increasing demand by a growing human population [1, 2, 3]. At the same time demands of ethanol has been increasing since it is considered to be an alternative transportation energy source other than food consumption [4, 5]. Considerable attention has been given to ethanol production from various available sugar substrates such as molasses, sugar cane juice ; starchy materials like rice, millet, corn, sorghum, wheat, potato, cassava [3, 5, 7, 8, 9, 10]; as first generation ethanol and cellulosic materials as second generation ethanol . Pearl millet, broken rice and sorghum are the major starchy materials used by Indian distilleries not only for the production of potable alcohol  but also for the fuel purpose (http://www.icrisat.org/text/research/grep/homepage/sgmm/chapter12.pdf). Moreover, Indian distilleries use these raw materials based on their avai lability and cost since these are seasonal grains [12, 13]. The increasing price of crude oil and other fossil fuels have increased the interest in alternative fuel sources around the world [14, 15]. Fuel alcohol production from starch materials needs constant process improvement for meeting the economic payback by lowering the high price energy consumption and improvement in fermentation efficiency in order to be considered as a viable alternative to fossil fuel. At present, production costs for ethanol is INR 20 to 23 per liter from molasses based ethanol plant (1.0 INR = 0.0225683 USD), which is slightly higher than the Brazil using molasses (INR 14 to 16 per liter) . The Indian distilleries seek technological alternatives that would lower cost and provide higher margins in order to compete with gasoline and other fossil fuels. For the molasses based industry with 100KL per day capacity will require 450KWH power, 1620 to 1800 KL water per day for molasses dilution; and cooling water requirement will be 1080 KL per day. For a plant of s uch capacity, 2.0 to 2.3 MT of steam for 1.0 KL of ethanol production is required. In India, due to limited availability of molasses, molasses alone is not sufficient to meet the growing ethanol needs of the country, especially for use as a biofuel. Furthermore, the government of India is aggressively promoting the concept of blending petrol (gasoline) with ethanol to reduce dependence on petrol, and about 500 million liters of ethanol would be required every year, even if 10% ethanol is blended with gasoline (http://www.