A high-grade semi-anthracite coal was found to contain 90.04% C, 0.79% S, and 1.2% N on an ash and moisture-free basis. If this coal were burned in excess air saturated with water at 30°C and 105 kPa, a flue gas with the following Orsat analysis results: 10.83% CO₂, 1.08% CO, 0.22% H₂, 8.67 % O₂, and 79.2% N₂. Calculate the ultimate analysis of coal (ash/moisture free) and the % excess air.

Combustion of Solid Fuels (Coal)December 7, 9, 14 and 16 2015Combustion of coal with no combustibles in the refuseRefuse – Unburnt solid material left during the combustion of solid fuels.Sample Problem 1:A high grade semi-anthracite coal was found to contain 90.04% C, 0.79% S, and 1.2%N on an ash and moisture free basis. If coal were burned in excess air. Saturated with water at 30°C and105 kPa, aflue gas with the following orsat analysis results: 10.83% CO2, 1.08% CO, 0.22% H2, 8.17% O2and 79.7% N2. Calculate:a.Ultimate analysis of coal (ash-and-moisture free)b.Percent excess air.Sample Problem 2:A medium volatile bituminous coal has an as received analysis of 27.13% VCM, 62.52%FC, 11% ash, 0.95% S and 1.28% N. The coal sample is found to have a calorific value of 32.3MJ/kg. Thecoal is then burned with excess air supplied at 30°C, 756 torr with 80% relative humidity. Partial Orsatanalysis of the stack gas resulted in 9.78% CO2and 2.45% CO. Calculate:a.Percent excess oxygenb.Complete and Orsat analysis of the stack gasc.m3of the stack gas (270°

Combustion of Solid Fuels (Coal)December 7, 9, 14 and 16 2015Combustion of coal with no combustibles in the refuseRefuse – Unburnt solid material left during the combustion of solid fuels.Sample Problem 1:A high grade semi-anthracite coal was found to contain 90.04% C, 0.79% S, and 1.2%N on an ash and moisture free basis. If coal were burned in excess air. Saturated with water at 30°C and105 kPa, aflue gas with the following orsat analysis results: 10.83% CO2, 1.08% CO, 0.22% H2, 8.17% O2and 79.7% N2. Calculate:a.Ultimate analysis of coal (ash-and-moisture free)b.Percent excess air.Sample Problem 2:A medium volatile bituminous coal has an as received analysis of 27.13% VCM, 62.52%FC, 11% ash, 0.95% S and 1.28% N. The coal sample is found to have a calorific value of 32.3MJ/kg. Thecoal is then burned with excess air supplied at 30°C, 756 torr with 80% relative humidity. Partial Orsatanalysis of the stack gas resulted in 9.78% CO2and 2.45% CO. Calculate:a.Percent excess oxygenb.Complete and Orsat analysis of the stack gasc.m3of the stack gas (270°

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