Biofuel : Types of BioFuels

Types of BioFuels

Bio fuel can be in solid, liquid or gaseous form. Other than wood, charcoal, dried manure are solid bio fuels. Fuel in liquid form is considered the most convenient for transportation sector. For this reason, liquid Bio fuel is the one with the highest demand today. Most widely used in this category are Bio ethanol and Bio diesel.

Ethanol

Bio ethanol, is the most common type of Bio alcohol, others being, bio propanol and bio butanol. Ethanol is produced by fermentation, a chemical reaction which converts sugar or starch to alcohol. The reaction is caused by yeast or bacteria. Ethanol is also the most widely used bio fuel in the world. Brazil holds the first place in using ethanol. Ethanol is used as the blending agent with gasoline, in different proportions. The mixture helps in boosting octane content and reduces toxic smog. While butanol can be directly used as a fuel in petrol engines, without requiring any technical alterations, a gasoline- ethanol mixture containing 15% ethanol is needed to run the present-day petrol engines.

Bio diesel

Another most anticipated future fuel. The non toxic fuel is produced after chemical reaction between alcohol and fatty acid alkyl esters from vegetable oil, animal fats or plant extracts. The undesired by-products of the reaction such as glycerine and methyl ester are removed using a refinery process, ‘Transesterification’. Fuel-grade Biodiesel must be produced to strict industry specifications (ASTM D6751 in the USA, EN 41214 in Europe) in order to ensure proper performance. Bio diesel, in comparison to ethanol, is more compatible. It can be directly used in any unmodified diesel engine as fuel. Also, it can be blended with mineral diesel at any levels. No need to mention, the cleaner and greener bio diesel, plays a commendable role in reducing toxic emissions.

Bio fuel is catching attraction and admiration of transportation sector not only because it is a renewable resource, but as it also helps in improving the performance of engine by reducing harmful emissions and increasing octane content.

Bio gas

This one has the potential to be the rural lifeline. Bio gas mainly consists of methane. It is produced by anaerobic digestion of organic matter like agricultural or animal waste, weeds and other bio degradable sources which are available at no cost. Setting up the digester and some maintenance is the only thing required and people can get a clean and cheap source of energy. Moreover, the solid by-product digestate is used as fertilizer. Use of Bio gas is increasing especially in developing countries. A less clean form of biogas is landfill gas, which is produced naturally by anaerobic digestion.

‘Syngas’, which can be directly burnt in internal combustion engine, is produced by series of process like gasification, combustion and pyrolysis.