A biofuel is made from a biological process known as carbon fixation. These biofuels are gotten from the conversion of biomass, solid biomass, liquid fuels as well as biogases. The biofuels are continued to be known because of the high prices of fossil fuels and also for the purposes of ensuring fuel security in various countries. (Caye, D. & Terry W.2008). The biofuels are produced from two distinct ways; that is through metabolic by-products or from living organisms. Examples of biofuels include; bioethanol which is an alcohol made from fermentation process. Another example of biofuels is biodiesel which is made from vegetable oils ...view middle of the document...
This is achieved by the reaction of the materials at a very high temperature of up to 700 °C without combustion process. The process takes place under controlled oxygen and steam and produces gas mixture known as syngas or producer gas which in itself is a fuel. (Caye, D. & Terry W. 2008). The energy which is gotten from both combustion and gasification is a source of renewable energy when the compounds which are gasified are obtained from biomass.
Gasification has the advantage of being efficient compared to direct combustion. This is because there is a possibility of it being combusted at very high temperatures or even in fuel cells. The thermodynamic to the efficiency which is pointed out by Carnot’s rule is very high. (Caye, D. & Terry W. 2008). The resultant gas known as syngas can be burned directly in gas engines or it can be used to manufacture methanol and hydrogen. This process uses waste materials which would otherwise be disposed off. The use of high temperatures ensures that corrosive as elements such as chloride and potassium are gotten ride of. This results to the production of clean fuel which is not problematic to the environment.
Gasification takes place in a gasifier in which several reactions take place. Firstly, the drying of the feedstock takes place at a temperature of 100°C.This followed by the combustion process which depend on the properties of carbonaceous materials. The combustion equation is as follows. (Mitchell, D. 2010). .The gasification process takes place when carbon reacts with steam to produce hydrogen and carbon monoxide.The equation is as follows .The final reaction is the water gas shift reaction which balances the concentration of carbon monoxide,steam,carbon dioxide and hydrogen.(Pimentel, D. &Patzek, T. W. 2005).
The reason why a limited a mount of oxygen is added to the gasifier is to enable the burning of organic materials to convert them to hydrogen and carbon dioxide.more reaction takes place when the resultant carbon dioxide and water inform of steam reacts to form methane and carbon dioxide.The reaction rates can be increased by adding catalysts such as the reaction moves closer to equilibrium with a fixed a mount of time. (Li, H. & Cann, A. F. 2010).
This process involves the use of catalysts and transesterification to produce biodiesel. There are two processes involved here. Depolymerization which creates renewable diesel and the other one is hydrotreating which produces green diesel or hydrogenation derived renewable diesel. Hydrotreating involved the use of hydrogen and catalysts.
This is one of the methods used to make biofuels. It involves burning of biomass such as dead trees in the absence of oxygen.
This is a very important chemical reaction which takes place before combustion and gasification processes. (Li, H. & Cann, A. F. 2010). It occurs very fast in approximately within two seconds. The products of this...