Gasification

Gasification is a very important process in using clean coal. It is discussed in the section about pre-combustion clean coal, but here it is in greater detail:
 * Gasification**

Gasification is where rocks, such as coal, are liquified for use as fuel, perhaps in an automobile, which is one of the reasons that people are becoming more excited about it and more oblivious to its cost.

The coal gasifier, labeled (1) in the diagram above, is the first and most important step in the process. Coal, water, and air are mixed together under heat (over 2200 degrees Fahrenheit) and high pressure. The result is synthesis gas, a.k.a. syngas, and non-carbon based minerals that are in the form of fragments and ash. The syngas is composed of carbon monoxide and hydrogen gas, along with other minerals that are removed further along in the process. There are several reactions going on during this process:
 * C + .5O2 = CO + heat (This reaction is exothermic)
 * CO + H2O = H2 + CO2
 * C + 2 H2 = CH4

These reactions produce hydrogen gas, carbon dioxide, and methane gas (also produced by bovine flatulence), the primary components of syngas, except methane.

The syngas is then subjected to a number of processes designed to remove other minerals and substances from the syngas and make it suitable for clean combustion.
 * 1) Heat exchangers and filters cool the gas and remove most of the solid contaminants. (2 in the diagram)
 * 2) Mercury, a dangerous poison, is removed by passing the syngas over a bed of charcoal. (#3)
 * 3) The sulfur in the syngas is removed last. (#4)

After the conclusion of the gasification process, the syngas is sent through a turbine to generate electricity. Also, the steam created throughout the process is used to move another turbine to generate even more electricity. Approximately 2/3 of the power generated is from the syngas turbine, and 1/3 is from the steam turbine. (Popular Mechanics)

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