Rubric for Biofuel
Don't be a Billy goat about reading
What is Bioethanol
The principle fuel used as a petroleum substitute is bioethanol. Bioethanol is mainly produced by the sugar fermentation process, although it can also be produced by the chemical process of reacting ethylene with steam. The main source of sugar required to produce ethanol comes from fuel or energy crops. These fuel crops are normally grown specifically for energy use and include maize, corn and wheat crops, waste straw, willow, sawdust, reed canary grass, cord grasses, jerusalem artichoke, myscanthus and sorghum plants. There is also ongoing research and development into the use of municipal solid wastes to produce ethanol fuel - See more at: http://www.makebiofuel.co.uk/bioethanol-production#sthash.JFpW6ERa.dpuf
Bioethanol produces only carbon dioxide and water as the waster products on burning, and the carbon dioxide released during fermentation and combustion equals the amount removed from the atmosphere while the crop is growing.
How is Bioethanol used / Bioethanol Blends
Ethanol is most commonly used to power cars although it is also used to power other vehicles, such as tractors, airplanes and boats. Like Biodiesel, engine old starting can be effected when using high blends of Bioethanol fuel in cars. EU markets have adopted E85 (85 percent Ethanol / 15 percent Gasoline) as the maximum blend to be used and this is the common standard which manufactures work to when making their cars run Bioethanol or “flexi-fuel”. In some colder climate its it recommended that an E70 blend is used.
A new type of fuel, SP95-E10 (Sans Plomb 95 Octane, Ethanol 10% = Lead Free 95 Octane containing 10% of Ethanol) is now being sold throughout France.
This fuel is not suitable for use in all cars and you should check compatibility with your vehicle manufacturer before using it. If in doubt use the standard SP95 or SP98 Octane unleaded fuel which continues to be available alongside the new fuel.
How Bioethanol is made
The basic steps for large scale production of ethanol are: fermentation of sugars, distillation, dehydration and denaturing (optional). Prior to fermentation, some crops require saccharification or hydrolysis of carbohydrates such as cellulose and starch into sugars. Saccharification of cellulose is called cellulolysis (see cellulosic ethanol). Enzymes are used to convert starch into sugar.
Ethanol is produced by microbial fermentation of the sugar. Microbial fermentation will currently only work directly with sugars. Two major components of plants, starch and cellulose, are both made up of sugars, and can in principle be converted to sugars for fermentation. Currently, only the sugar (e.g. sugar cane) and starch (e.g. corn) portions can be economically converted. However, there is much activity in the area of cellulosic ethanol, where the cellulose part of a plant is broken down to sugars and subsequently converted to ethanol.
For the ethanol to be usable as a fuel, water must be removed. Most of the water is removed by distillation. The purity is limited to 95-96% due to the formation of a low-boiling water-ethanol azeotrope. This may be used as fuel alone but unlike anhydrous ethanol it is immiscible in Petrol meaning it can not be mixed i.e. E85. The water fraction is typically removed in further treatment in order to burn with in combination with petrol in petrol engines
- See more at: http://www.makebiofuel.co.uk/bioethanol-production#sthash.JFpW6ERa.dpuf