Under the FutureGen 2.0 project sponsored by the U. S. Department of Energy, a novel process is used to convert coal into electricity with minimal greenhouse gas (CO2) emissions to the atmosphere. In the process, coal is combusted in a boiler with pure O2 ; the heat released produces steam, which is then used for heating and to drive turbines that generate electricity. An excess of O2 is supplied to the boiler to convert all of the coal into a flue gas consisting of CO2, steam and any unreacted oxygen. The mass flow of coal to the boiler is 50kg/s, and O2 is fed in 8.33% excess. For the purposes of this analysis, the chemical formula of coal can be approximated as C5H8O2 . a) Draw and label the flowchart and carry out the degree of freedom analysis using balances on atomic species.
b) Determine the molar flow rate of oxygen supplied to the boiler.
c) Solve for the remaining unknown flow rates and mole fractions. Determine the molar composition of the flue on a dry basis.