Unit operation (b) in Table 5.4 is to be heated by injecting live steam directly into the bottom plate of the column instead of by using a reboiler, for a separation involving ethanol and water. Assuming a fixed feed, an adiabatic operation, atmospheric pressure throughout, and a top alcohol concentration specification:(a) What is the total number of design variables for the general configuration?(b) How many design variables are needed to complete the design? Which variables do yourecommend?

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Variable Specification Case I1. Nomber of Case I, Companent Recoveries Specified Equilibrium Stages Specified Unit Operation No 1. Recovery of one key component 2, Reboiler heat duty L. Number of SI Reboiled stripping (ane inlet 2N -C-3 stages 2. Bottoms fow rate stream) Partial ebaile L. Ratio of vapor distillute to liquid distilate 2. Number of 1. Ratio of vapor distillate to liquid distillate 2N +C+9 (g) Distillaticon (one inlet stream, partial condenser, partial eboiler, both liquid and Vврог Parial condenser 2. Recovery of Tight key component 3. Recovery of heavy key component stapes above leed stuge 3. Number of Liquid Divider stages below feed slage 4. Reflus ratio S. Liqoid distillate Ilow rate 4. Refux ratio vapor distillates) (> minimum) Partial rebeijet 5. Optimal feed stage 1. Condensate at saturution I. Condensate at saluration (hi Extractive distillation (two inlet streams, total condenser, partial reboiler, single-phase condensate) 2N + 2C + 12 Total condenser emperatare 2. Recovery of light key component 3. Recovery of heavy key component 4. Reflux ratio (> minimum) 5. Optimal feed stage 6. Optimal MSA stage temperature 2. Number of Liquid -Divides stages above MSA stage MSA. 3. Number of stages between MSA and feed slages 4. Number of stages below feed stage 5. Reflun ratio 6. Distillase flow ralte Partial reboiler 1. Recovery of one key соmpoвent 1. Number of stages 2N + 20 +5 Liguid-liquid extraction (two inlet ý MSA streums) I. Recovery of спе key component 1. Number of Stripping (two inlet steeams) 2N + 20+5 stages MSA