G-1

Three-hundred pounds of carbon are burned with 65,000 cu ft of air initially at 14.7 psia and 300 F. Assume that the carbon is pure, and calculate the volumetric combustion analysis.

G-2

A coal contains 4 per cent moisture, 23 per cent volatile matter, 64 per cent fixed carbon, and 9 per cent ash and has a heating value of 14,100 Btu per lb. Determination of the carbon in the coal shows it to be 79 per cent. The refuse removed from the ash pit of a grate-fired furnace using this coal contains 62 per cent moisture (due to wetting down of the ashes by hose to lay dust), 3 per cent volatile combustible matter, 11 per cent fixed carbon, and 24 per cent ash. Estimate the per cent of the heating value of this coal lost in the furnace as unburnt combustible and the per cent carbon fired which remains in the refuse.

G-3

Methane, CH ₄, is burned in four times the theoretical air quantity, i.e., the excess air is 300 per cent. As a very crude approximation, it may be assumed that the specific heats of air methane, and the combustion gases are equal. If the air is burned at 100 F, estimate the products of combustion temperature if the higher heating value of methane is 21,500 Btu per lb.

G-4

In the combustion of coal, what is the amount of heat liberated per pound of carbon in complete combustion to CO ₂