In underground coal combustion in the gas phase, several reactions take place, including CO + 1/2 O2 CO2 (1)

H₂ + O₂ H₂O (2)

CH₄ + O₂ CO + 2H₂O (3)

where the CO, H2 and CH4 come from coal pyrolysis.

If a gas phase composed of 13.54% CO, 15.22% CO2, 15.01% H2, 3.20% CH4 and the balance N2 is burned with 40% excess air, the applicable reactions become:

CO + O₂ CO₂ (4)

H₂ + O₂ H₂O (5)

CH₄ + 2O₂ CO₂ + 2H₂O (6)

Under these conditions,

How many moles of air are required per mole 100 moles of gas fed?

What is the analysis of the product gas on a wet basis?

What is the analysis of the product gas on a dry or Orsat basis?