Working of wood gasifier:
The term Gasification is used for chemical processes by which a gaseous fuel is produced from a solid fuel. Wood gas was used for heating, lighting and even as vehicle fuel. There are many different designs of modern gasifier, but essentially one basic process: hot steam and oxygen interacting with the solid fuel. The gasification reaction do not occur easily, and need operating temperatures from a few hundred to over a thousand degree Celsius, with pressures from a little above atmospheric pressure to 30 times this. The process begins with the release of the volatiles from the heated solid, leaving the char. These two components in turn undergo reactions with steam and oxygen, resulting in producer gas, a mixture of combustible components together with carbon dioxide and water. Further processing may break down some of the combustibles to give a cleaner gas. Nitrogen will also be present if air is used, rather than oxygen, and the energy content of the resulting gas is then only 3-5MJ/m3 , about a tenth of that of natural gas.