Bioethanol and its Production

Bioethanol

1. Erg 211 renewable energy and green technology (1+1) BIOETHANOL AND ITS PRODUCTION By: T.Dhanasriyan 2017037004

2. ETHANOL = Ethanol derived from agricultural sources (as distinct from petrochemical sources) Originally, it was produced by the spontaneous fermentation of sugars and was consumed by ancient races for its intoxicating effects. The Arabs and Romans learned to isolate the alcohol and to employ it industrially in the preparation of perfumes, cosmetics, and medicines. In the current time, the importance of alternative energy source has become even more necessary due to : 1). depletion of limited fossil fuel stock 2). safe and better environment

3. Cont… Replacing fossil fuels with so-called biofuels , such as bioethanol , is one way of reducing greenhouse gas emissions from the transport sector, which is responsible for a considerable proportion of total CO 2 emissions. BENEFITS OF BIOETHANOL Less dependence on crude oil It is a renewable fuel. I ncrease octane number (a standard measure of the performance of motor fuel) Reduces air pollution, cleaner environment due to cleaner combustion  l ower net carbon dioxide emissions Helping emerge a new market Expanded market opportunity in the agricultural field

4. RAW MATERIALS FOR BIOETHANOL There are in general three groups of raw material: 1). Sugar : Beet, Sugar Cane, Sweet Sorghum and Fruits. 2). Starchy Material such as corn, wheat, rice, potatoes, cassava, sweet potatoes etc. 3). Cellulose materials like wood, used paper, crop residues etc.

5. STEPS FOR ETHANOL PRODUCTION Fermentation Process Distillation Process Dehydration Process

6. BIOETHANOL PRODUCTION Ethyl alcohol production is based on two major procedures : (1). Fermentation . Cereal grains (corn, wheat, barley, sorghum, or rye); sugarcane (molasses); sugar beets; fruit product wastes; other starch crops (potatoes or rice); sulfite liquors (paper pulping); and such high cellulose-containing materials as wood, crop residues, and cultivated fiber crops. (2). Chemical synthesis . Petroleum and natural gas; coal; oil shales ; and tar sands. Synthetic alcohol is not purer or better quality than fermentation alcohol for industrial use.

7. Used as a raw material in ethanol production By exposing starch from peel of corn with water Enzymes are added to the mash that convert starch to dextrose, a simple sugar. yeast is added and conversion from sugar to ethanol and carbon dioxide begins. Production of Corn

8. Production of sugar cane Extraction of sugar Then it is added to yeast for fermentation process lactic acid, hydrogen, carbondioxide , ethanol are produced

9. SECOND GENERATION BIOETHANOL LIGNOCELLULOSE The energy balance is very positive. Net CO 2 release ≈ zero

10. Cellulose is hydrolysed to glucose units Hemicellulose is degraded to mainly glucose, galactose, mannose, xylose and arabinose Lignocellulosic material can be degraded to fermentable sugars, but is more difficult to convert than starch derived raw materials

11. Bioethanol production from lignocellulose Enzyme production Enzymatic hydrolysis Fermentation Pretreatment Enzymatic Hydrolysis Fermentation Down stream processing Ethanol or butanol Chipping/ grinding Lignocellulosic material Production of cells

12. advantages Exhaust gases of ethanol are much cleaner ethanol-blended fuels such as E85 (85% ethanol and 15% gasoline) reduce up to 37.1% of GHGs › output of energy during the production is more than the input the CO2 released in the bioethanol production process is the same amount as the one the crops previously absorbed during photosynthesis

13. disadvantages Not as efficient as petroleum › energy content of the petrol is much higher than bioethanol › its energy content is 70% of that of petrol Engines made for working on Bioethanol cannot be used for petrol or diesel › Due to high octane number of bioethanol , they can be burned in the engines with much higher compression ratio Used of phosphorous and nitrogen in the production › negative effect on the environment Cold start difficulties › pure ethanol is difficult to vaporise

14.  For bioethanol to become more sustainable to replace petrol, production process has to be more efficient › Reducing cost of conversion › Increasing yields › Increase the diversity of crop used  As microbes are use to convert glucose into sugar which is ferment in bioethanol › Microbiology and biotechnology will be helpful in the genetic engineering Conclusion