What is the liquefaction of coal?
Coal liquefaction is a process used to transform coal, solid fuel, for liquid fuel replacement such as diesel and gasoline. Coal liquefaction is historically used in countries without safe oil supply, such as Germany and South Africa. The technology used in the liquefaction of coal is relatively old and was first implemented during the 19th century to provide gas for interior lighting. Coal liquefaction can be used to produce oil for transport and heating in the future if raw oils are delivered.
Coal liquefaction takes place in two main stages; Coal gasification and gas-capalin (GTL). During the coal gasification, air and steam are added to the raw coal, which heats up to several hundred degrees of Fahrenheit (Celsius). Carbon in coal reacts with oxygen and water and produces other gases such as carbon dioxide, carbon monoxide, hydrogen and methane oxide. Carbon dioxide is a waste and can be venting into the atmosphere; Other gases can be disappeared or sent for further processing. During the 19th century, pElectric lighting, this gas was burned to provide a light source for buildings and streets.
The second phase of liquefaction of coal is also known as the Fischer-Tropsch process. Once the coal gas is filtered and processed, carbon water or carbon dioxide can be added to adjust the ratio between carbon monoxide and hydrogen. The hot gas then passes through the catalyst that causes condensation of oxide and hydrogen carbon monoxide into long hydrocarbon chains and water. The hydrocarbon chains can be used as a replacement for oil products such as gasoline, kerosene and heating oil, while water can be recycled and used as steam at the beginning of the liquefaction process.
Coal liquefaction is generally more expensive than oil fuel production, but may become economic if oil is rare or neutalable. During World War II it was employed by the German Army, which had a large supply of coal but small oil,To operate tanks and other war machines. Later, during apartheid in South Africa, coal liquefied helped to replace oil loss for sanctions. In the case of a major disturbance of oil supply, coal liquefy plants can be brought online relatively quickly, due to the simplicity of technology and high availability of raw coal.