Technology of Fischer-Tropsch operation

Production of Synthesis Gas. Synthesis gas for the Fischer-Tropsch reaction consists of mixtures of hydrogen and carbon monoxide in ratios of from O.7H2 ICO to 2.5H2 ICO. Mixtures of hydrogen and carbon monoxide have been made in the past by water-gas generators operated cyclically, usually using coke as a fuel. The coke is first heated by an air blow (1) to heat the bed, and then, during the make cycle, steam is blown through the hot coke bed (2) to produce hydrogen and carbon monoxide  

Reaction (2) is endothermic when the temperature of the coke bed becomes too low, the make cycle is ended and air is blown to heat the bed to high temperatures again. 

Water-gas generators have been widely used to make heating gas of about 300 Btu per cu ft as well as gas for the production of hydrogen to be used in ammonia synthesis. Because of the cyclic nature of this method, the high cost of coke in relation to coal, and the relatively low productive capacity, water-gas generators are not suffiriently economical to be considered for the manufacture of synthetic fuels. 

Other processes are available for the continuous production of synthesis gas from natural gas, liquefied petroleum gas, high-boiling oils, or solid fuels. Natural gas and liquefied petroleum gas can be reformed with steam 

Pressure gasification can be accomplished with fine coal in suspension and in fluidized beds or with lump coal in fixed beds. Reactions (1) and (2) occur continuously, and at the high temperature attained by the use of oxygen, reaction (3) occurs  

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