Afurnace is fired with coal with the following analysis: 36.3% vcm, 49.6% fc, 10.7% ash, 3.4% moisture, 1.2 % n and 5.1% s. its calorific value is 29.5 mj/kg. analysis of the wetted refuse shows 12% c, 65% ash and 23% water. dry air is supplied at 27oc and 1 atm. the stack gases leave at 350oc, 745 mm hg with a partial orsat analysis of 8.71% co2, 1.74% co and 0.35% h2. calculate:

a) % excess air

b) complete orsat analysis

c) cubic meter stack gas/kg coal