Cereal is being dried in a dryer by air flowing countercurrent to the cereal (sec flowchart...

 

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Cereal is being dried in a dryer by air flowing countercurrent to the cereal (sec flowchart below). To minimize breakage of the cereal flakes, a portion of the exit air from the dryer is recycled. The moisture content (mass fraction) of the various streams is as follows: Fresh air = 0.0082, wet cereal = 0.200, dried cereal = 0.050, air entering dryer = 0.042, and exit air = 0.181. Take as a basis 1000 kg/h of wet cereal entering the dryer and assume steady state. What is the flow rate (F in kg/h) of the fresh air, and that of the recycle stream (R in kg/h)? Write enough independent equations (neither more, nor less) that, if solved, they will provide F and R. Exit air (0.181, E(kg/h)) Wet cereal (0.200, 1000 kg/h) Recycle, R(kg/h) DRYER X Air entering dryer (0.042, G (kg/h)) - Fresh air, (0.0082, F(kg/h)) Dried cereal (0.05, D(kg/h)) Cereal is being dried in a dryer by air flowing countercurrent to the cereal (sec flowchart below). To minimize breakage of the cereal flakes, a portion of the exit air from the dryer is recycled. The moisture content (mass fraction) of the various streams is as follows: Fresh air = 0.0082, wet cereal = 0.200, dried cereal = 0.050, air entering dryer = 0.042, and exit air = 0.181. Take as a basis 1000 kg/h of wet cereal entering the dryer and assume steady state. What is the flow rate (F in kg/h) of the fresh air, and that of the recycle stream (R in kg/h)? Write enough independent equations (neither more, nor less) that, if solved, they will provide F and R. Exit air (0.181, E(kg/h)) Wet cereal (0.200, 1000 kg/h) Recycle, R(kg/h) DRYER X Air entering dryer (0.042, G (kg/h)) - Fresh air, (0.0082, F(kg/h)) Dried cereal (0.05, D(kg/h))