The gasification process is an underground generator or gasifier occurs as follows: the coal is set on fire in a section of the coal seam directly at the coal pillar without preliminary fractionation. Blast air is fed to this combustion center often the blast employs steam. Oxygen with steam on striking the layer of actively burning coal enters into a reaction with it; the carbon burns because of the oxygen and the steam forming carbon monoxide and carbon dioxide, freeing the hydrogen of the steam. The carbon dioxide that forms, on coming into contact with the red hot carbon, reacts with it and partially converts into carbon monoxide.