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• Mohd Azman Suwandi

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ECH3112:Homework Prepared by Syafiie September 28, 2015 1. Two tank system Page 46, No. 2.3, Serbog, Edgar, Mellichamp, Doyle, Proces Dynamics and Control. 2. Closed tank Page 46, No. 2.4, Serbog, Edgar, Mellichamp, Doyle, Proces Dynamics and Control. 3. Flash drum Page 101, No. 3-11, Smith, Corripio, Principles and practice of automatic process control. Consider the flash drum shown in Fig. P3-4. Here z(t), x(t), and y(t) are the mole fractions of the more volatile component in the feed, liquid, and vapor streams, respectively. The total mass of liquid and vapor accumulated in the drum, the temperature, and the pressure can all be assumed constant. If equilibrium between the vapor and liquid phases leaving the drum is assumed, then the following relationship between y(t) and x(t) can be established. The steady-state and other process information is M = 500 kmoles, F = 10 kmoles/s, L = 5 kmoles/s, (Y = 2.5, and x(O) = 0.4. Develop unsteady state model. Obtain the transfer function that relates the outlet liquid composition, x(t), to the feed composition, z(t). Determine also the numerical value of all the terms in the transfer function.

Figure 1: flash separation

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