Gaseous fuel is produced by gasifying coal or coke in a reactor called gas producer. Gaseous fuels have several advantages like

• it is easy to handle.
• Combustion is rapid in comparison to coal or fuel oil.
• Less excess air for combustion is required than for combustion of fuel oil and coke.

Thermodynamics of Gasification:

Equilibrium conversion of C of fuel into gaseous fuel

1.   Air only

Consider gasification of 1 mole of carbon. Stoichiometrically ½ mole of oxygen is required to produce 1 mole of CO. One mole of oxygen is obtained from 4.76 moles of air, which means that every  mole of oxygen carries 3.76 moles of with it. Thus if the initial state of reactants is and and final state is CO and , the following gasification reaction can be written:  

(1)

Gaseous fuel consists of CO and in which

volume of gaseous fuel = 5.38 m³/kg of carbon (at 273K, 1 atm.)