subject: Gasification Technology 101 [print this page] Gasification technology is the newest and by far considered the best available waste-to-energy method in terms of both energy generation efficiency and environment safety. Gasification involves the conversion of the combustibility found in organic materials such as coal, petroleum, befoul, or biomass, into carbon monoxide and hydrogen. Such conversion can be achieved by making the materials go through extreme temperatures within a chamber with controlled oxygen and/or steam. After the materials are broken down they result in a gas mixture called synthetic gas or syngas. Gasification by itself is already a fuel, but it can further be processed into higher forms of fuel like electricity.
Gasification is like an exponentially improved form of incineration, in which the amount of energy produced is several times more with almost no harmful by-products created in the process. The greatly increased efficiency is the result of the extreme temperature combustion of the materials. Syngas can also be used to generate methanol and hydrogen via internal combustion engines or to produce synthetic fuel via the Fischer-Tropsch process. The use of syngas in generating green electricity however, is considered to be most promising. Gasification technology releases almost no harmful elements in the environment. Carbon emissions are greatly reduced because the entire process is done in an oxygen limited chamber. The extreme temperatures also segregate the corrosive elements such as chloride and potassium.
Gasification Technology Chemistry
There are generally four steps that need to be taken in order to transform organic matter into syngas using gasification technology.
1. The pyrolysis (or devolatilization) process occurs as the carbonaceous particle heats up. Volatiles are released and char is produced, resulting in up to 70% weight loss for coal. The process is dependent on the properties of the carbonaceous material and determines the structure and composition of the char, which will then undergo gasification reactions.
2. The combustion process occurs as the volatile products and some of the char reacts with oxygen to form carbon dioxide and carbon monoxide, which provides heat for the subsequent gasification reactions. Letting C represent a carbon-containing organic compound, the basic reaction here is {
m C} + egin{matrix} frac{1}{2} end{matrix}{
m O}_2
arr {
m CO}
3. The gasification process occurs as the char reacts with carbon dioxide and steam to produce carbon monoxide and hydrogen, via the reaction {
m C} + {
m H}_2 {
m O}
arr {
m H}_2 + {
m CO}
4. In addition, the reversible gas phase water gas shift reaction reaches equilibrium very fast at the temperatures in a gasifier. This balances the concentrations of carbon monoxide, steam, carbon dioxide and hydrogen. {
m CO} + {
m H}_2 {
m O} lrarr {
m CO}_2 + {
m H}_2
Biosphere technology is yet another evolution in the waste-to-energy processes of green energy available today. After much research and development, gasification technology has transcended into being bio tech which is the conversion of solid wastes into clean electricity. The biosphere gasification process is revolutionary in the sense that it can be accomplished not only in gasification plants, it can be done in company buildings and even in ones household by simply having a biosphere machine installed. In rare occasions that not enough waste is available to feed the bio machine, biosphere flakes can be used as substitute to make sure that green energy never runs out for the institution.
