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Seat No.: Enrolment
GUJARAT TECHNOLOGICAL UNIVERSITY
ME SEMESTER-III EXAMINATION WINTER 2018
Subject Code: 2731602 Date: 19-Nov-2018
Subject Name: Computer Aided Product Process Design(CAPPD)
Time: 02:30 PM To 05:00 PM Total Marks: 70
Instructions:
1. Attempt all questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
Q.1 State the steps for Product and Process design in Chemical industries with a
neat flow diagram.
07
Explain the criteria of selection of equipments for vapor liquid separation
process.
07
Q.2 Show all possible sequences of ordinary distillation columns to separate
four components into four single component products C and
D. Draw all sequences clearly showing direct and indirect sequence.
Show how the number of possible sequence changes when other
alternatives are available with example.
07
Explain the various reactor models used for reactor networking system. 07
OR
Explain the stepwise procedure for the process design of falling
filmabsorber.
07
Q.3 Stabilized effluent from a hydrogenation unit is to be separated by ordinary
distillation column into four relatively pure products. Following data is
given:
Species Symbol Feed mole
rate
lbmol/h
Relative
volatility α
purity
i-butane A 300 4.3 95
n-butane B 500 3.1 92
i-pentane C 400 1.25 98
n-pentane D 700 1.0 98
The operating cost of each separator is as follows:
Unique
separator
Cost

Unique
separator
Cost

A/B 94900 B/CD 78200
B/C 59300 BC/D 185300
C/D 169200 A/BCD 133400
A/BC 112600 AB/CD 94400
AB/C 76800 ABC/D 241800
Determine the following:
1. Total number of possible sequences.
10
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2. Number of columns required in each sequence.
3. Draw each possible sequence.
4. Calculate operating cost of each sequence.
5. Determine the best sequence.

Write a short note on role of environment in design process.
04
OR
Q.3

Discuss the heuristics for determining favorable sequences in distillation column with proper example.
06

Explain in details with proper example different separation systems for gas mixtures.
08
Q.4
Design a spray chamber for the following duty:
Volumetric flow rate of boiler flue gas 24000 m3/h.
Pressure of gas 150 mm WC (gauge)
Temperature 80 90 0C.
SO2 concentration in boiler flue gas 4000 ppm.
Desired concentration of SO2 in outgoing gas 20 ppm.
Solvent used is 1 lime solution.
14
OR
Q.4

Develop a MILP model for separation of four component mixture with a neat superstructure diagram.
07

Explain design of venturi scrubber.
07
Q.5

Explain the role of simulation in design process and list the important softwares along with their application.
07

A plant manufactures two products each having two stages. The demands are 500,000 lb/yr for A and 300,000 lb/yr for B. The total production time is 6000 hours. Data on process times, size factors and cleanup times are given below. The production cycle is of 1000 hrs (42 days). The effective time for production in each cycle is 992 hours. Do the vessel sizing for the process.
Processing time (hour)
Size Factors (ft3/lb product)
Stage 1
Stage 2
Stage 1
Stage 2
A
8
3
0.08
0.05
B
6
3
0.09
0.04
07
OR
Q.5

Classify different types of batch plants with proper example.
07

A given batch plant produces one single product for which stage 1 requires 8hours/batch; stage 4 hours/batch and stage 7 hours/batch. If zero waittransfer is used, what is the cycle time? How many parallel units should be placedin each stage to reduce the cycle time to 4 hours? Draw GANTT charts and demonstrate.
07