How much air quantity required for burning the gas (LNG or LPG) or oil (LFO or HFO) per kilowatt ?

Question

The air pressure is about 6-7 kPa.

Answer 1

You'll have to do the formula.

O2 +N2+ Fuel = CO2 + H2O + N2

Remember that air is roughly 79% N2 and 21% O2 and that for normal combustion about 10% extra O2 is provided to insure complete combustion.

For gases you can assume mole ratios and volumetric ratios will be the same.

For liquid fuels you'll have to convert moles to mass units for fuel and air.

Have fun.