material balance. unit operation

U2.20 Gas containing 85.2 vol.% of ethane, 11.3 vol.% of methane, and nitrogen continually burn in a furnace. Wet air is used for combustion. The air contains an unknown amount of water vapor, and oxygen and nitrogen at a molar ratio of 21:79. The air excess is 30%, and the combustion yields CO, and H,0. The flue gases enter a dehumidifier, in which all the water is removed. 7.35 kg of water was collected in 1 hour and 12 minutes of operation. The volume flow rate of dry flue gases at the dehumidifier outlet was 15.5 dm's at a temperature of 60C and a pressure of 98 kPa. Calculate: i) the amount of used wet air in mh' at a temperature of 25C and a pressure of 98 kPa, ii) water vapor content in the incoming air (in vol.%), and iii) the composition of dry flue gases at the outlet of the dehumidifier (in vol.%). I Result: 54.69 m'hof humid air containing 2.00 vol.% of H,O is processed. The composition of dry flue gases is 5.20 vol.% of O, 84.98 vol.% of Ny, and 9.82 vol.% of CO2