Determine (i) the air-fuel ratio, (ii) the percentage of excess air,

Question

The composition of coal burnt during a boiler trial was follows: C=62%; H₂=3.6%; O₂=7.4% and ash = 27%. The volumetric analysis of the flue gas showed the following CO₂ =10.25%; CO = 0.80%; O₂ = 8.54% and N₂ = 80.41%

         Determine

         (i)    the air-fuel ratio,

         (ii)   the percentage of excess air,

         (iii)  the mass of CO2, CO, O2 and N2 in           the flue gases per kg of coal burnt.