Using the control loops in Table E.2.7 and E.2.8 with, the full composition model created in Exercise 24.1, evaluate the use of ratio control in Loop 2 of Table 24.4. In particular, indicate why ratio control should improve the plant performance for production rate (W4 set point) changes, but not for disturbance (x2D) changes. Your responses should be similar to those in Figures 24.6 and24.7.

Controlled Varinble Manipulated Variable/Valve Loop Number Coatroller Type Cascade (Secondary) A stream flow rate, wi B stream flow rate, wi Reactor temperature, TR Reactor level, Ha Flash unit feed temperature, T Flash unit liquid level, Ile A composition in product, 4A Flhsh unit pressure, Pr Condensci exit temperature, Tc Recycle sur ge tank ievel, HT Plant production rate, wa D cormposition in recycle, ao A feed stream, VI B feed stream, V Cooling water, V9 Reactor effluent, V3 Steam supply, Vjo Plant product, V. Recycde tiquid stream Vs Recycle vapor stream, V, Couling water, Viu rurge tine, Vs Set point for wa (FC1) Ratio wa:wi (RC 2) Ratio Feedback Feedback Feedback Feedback Feedback Feedhack Feedback Feedback Cascade (Primary) Feedback 10 11 12 2010 2000 (kgh) 1990 10 15 20 25 30 35 10.1 10.0 XAA 9,9 9.8 0. 10 15 20 25 30 35 0.14 0.12 ITO 0.10 0.08 10 15 25 20 30 35 Time (h)