Gasification is a process that uses heat, steam, and high pressure to convert coal or other carbon containing feedstock into a synthesis gas, or syngas. Syngas is composed primarily of hydrogen (H₂) and carbon monoxide (CO), gasses that can be used as fuel for power production.

Around for a long time. The gasification process has been around commercially for more than 200 years. Scientists knew about gasification potential as early as 1609, but Scottish engineer William Murdock was the true pioneer in the field. He developed a gasification process in 1792 by experimenting with different types of fuel, finally settling on coal gas as the most effective. The first coal gasification plant in the U.S., the Gas Light Company of Baltimore, was established in 1816. This plant produced town gas, which was produced locally and supplied to the town for cooking and lighting. When local industry started using town gas to light their factories, the night shift was created, helping to usher in the Industrial Age. By the early 1900s, the use of town gas declined in favor of electricity and natural gas. Since the 1920s, gasification has been used mainly to produce synthetic fuels and chemicals, especially when petroleum resources were scarce, as in times of war. With the changes in global energy supplies and advances in technology, gasification is again at the forefront and could be a major leader in providing clean, efficient energy.

	Click the diagram below for a larger view.
	Coal Gasification Process

The process. The coal gasification process involves mixing coal with steam at high temperatures and pressures with controlled amounts of air or oxygen in a gasifier or gasification reactor. The temperature and pressure inside a gasifier can reach 2600ºF (1426ºC) and 1000 pounds per square inch (psig). These conditions break the carbon molecules apart and form the syngas, which is combustible. The syngas is then cooled and cleaned to remove contaminants such as sulfur and carbon dioxide (CO₂). At this point, the syngas can be used as a fuel or refined for use in a number of chemical processes. The diagram below shows a picture of the coal gasification process.