100 kg of wet solids containing 40% moisture by weight are dried to 10% moisture content...

 

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100 kg of wet solids containing 40% moisture by weight are dried to 10% moisture content by weight by passing moist air over them at 95C, 106 kPa. The partial pressure of water vapour in the entering air is 1.34 kPa. The exit air has a dewpoint of 60C. (a) Sketch and label the dryer with wet solids entering and leaving, and moist air entering and leaving, with all data on the sketch. [5 marks] (b) How many moles of HO are evaporated from the wet solids to produce the partially dried solid product with 10% moisture? [6 marks] (c) What are the mole fractions of HO and dry air, in the streams of moist air entering and leaving the dryer? Hence calculate the molar flow rate of moist air entering. [6 marks] (d) What is the volume required (nearest m) of moist air at 95C, 106 kPa? [3 marks] A saturated HO-temperature table is located at the end of this paper, for your reference. 100 kg of wet solids containing 40% moisture by weight are dried to 10% moisture content by weight by passing moist air over them at 95C, 106 kPa. The partial pressure of water vapour in the entering air is 1.34 kPa. The exit air has a dewpoint of 60C. (a) Sketch and label the dryer with wet solids entering and leaving, and moist air entering and leaving, with all data on the sketch. [5 marks] (b) How many moles of HO are evaporated from the wet solids to produce the partially dried solid product with 10% moisture? [6 marks] (c) What are the mole fractions of HO and dry air, in the streams of moist air entering and leaving the dryer? Hence calculate the molar flow rate of moist air entering. [6 marks] (d) What is the volume required (nearest m) of moist air at 95C, 106 kPa? [3 marks] A saturated HO-temperature table is located at the end of this paper, for your reference.