Pune University BE Process Engineering Costing and Plant Design
Question Papers
B.E. (Chemical) PROCESS ENGINEERING COSTING & PLANT DESIGN
(2008 Pattern) (Sem. – II)
Time :3 Hours] [Max. Marks :100
Instructions to the candidates:
1) Answer three questions from Section -1 and three questions from Section – II.
2) Answers to the two sections should be written in separate books.
3) Neat diagrams must be drawn wherever necessary.
4) Pigures to the right indicate full marks.
5) Use of logarithmic tables slide rule, Mollier charts, electronic pocket calculator and steam tables is allowed.
6) Assume suitable data, if necessary.
SECTION – I
QIA a) Enlist the factors required and explain them in detail for the comparison of different processes to make the same product. [9]
b) Illustrate the concept of material balance with reaction using suitable neat flow diagram. Take a basis of your choice. [9]
OR
Q2) a) Write the sample specification sheet for the shell and tube heat exchanger which show the following [9]
i) Identification.
ii) Function.
iii) Operation.
iv) Materials handled.
v) Basic Design Data.
vi) Essential controls.
vii) Insulation requirements.
viii) Allowable tolerences.
ix) Special information such as material of construction, gaskets, supports etc.
b) What are the factors that govern the selection of plant site or location? Explain them in details. [9]
Q3) a) Draw and explain the tree diagram showing the cash flow for industrial operations. [8]
b) The original investment for an asset was Rs. 10,000 and the asset was assumed to have a service life of 12 years with Rs. 2,000 salvage value at the end of the service life. After the asset has been in use for 5 years, the remaining service life and final salvage value are reestimated at 10 years and Rs. 1,000 respectively. Under these conditions, what is the depreciation cost during the sixth year of the total life if straight – line depreciation is used? [8]
OR
Q4) a) Write a note on types of taxes and insurances and explain them in detail. [8] b) A reactor, which will contain corrosive liquids, has been designed. If the reactor is made of mild steel, the initial installed cost will be Rs. 5,000 and the useful – life period will be 3 years. Since the stainless steel is highly resistant to the corrosive action of the liquids, it has been proposed as an alternative material to mild steel. The stainless – steel reactor would have an initial installed cost of Rs. 15,000. The scrap value at the end of the useful life would be zero for either type of reactor, and both could be replaced at a cost equal to the original price. On the basis of equal capitalized costs for both types of reactors, what should be the useful – life period for the stainless – steel reactor if money is worth 6% compounded anually? [8]
Q5) a) An industry is producing 3 lakhs kgs of Na_{2}CO_{Q} per annum. The total capital investment is 1 crore. The working capital is 15% of total capital. Raw material cost is 5 Rs./kg for the production. Labour cost is
4 Rs./kg, the product utilities 2.5 Rs./kg and packaging 1 Rs./kg. The product is sold at a price of 35 Rs./kg. Find manufacturing cost, total production cost and profit earned before taxes per kg of the product. [8] b) Write a note on cost indexes and explain their importance while estimating equipment costs by scaling such as six – tenths – factor rule. [8]
OR
Q6) a) A company has 3 alternative investments, which are being considered. Because all there investments are for the same type of unit and yields same service only, one of the investment can be related. If a company incharge expects 15% rate of return on original investment, which one will be suitable? [8]
Item |
Investment |
Investment |
Investment |
(I) |
(II) |
(III) | |
Initial fixed capital (Rs.) |
1,00,000 |
1,70,000 |
2,10,000 |
Wroking capital Investment(Rs.) |
10,000 |
10,000 |
15,000 |
Annual Cashflow (Rs.) |
30,000 |
52,000 |
59,000 |
Annual expenditure (Rs.) |
15,000 |
28,000 |
21,000 |
b) With neat diagrams, explain the mathematical methods for profitability evaluation. [8]
SECTION – II
Q7) a) With a neat diagram explain the break – even chart for production schedule and its significance for optimum analysis. [8]
b) A plant produces refrigerators at the rate of P units per day. The variable costs per refrigerator have been found to be Rs. 47.73 + 0.1P^{12}. The total daily fixed charges are Rs. 1750, and all other expenses are constant at Rs. 7325 per day. The profit is selling price per refrigerator minus total cost per refrigerator. Total cost per refrigerator is given as,
C_{T} = 47.73 + 0.1P^{12} + (1750 + 7325)/P If the selling price per refrigerator is Rs. 173,
determine : [8]
i) The daily profit at a production schedule giving the minimum cost per refrigerator.
ii) The daily profit at a production schedule giving the maximum daily profit.
iii) The production schedule at the break – even point.
OR
Q8) a) The following equation shows the effect of the variables x 8 y on the total cost for a particular operation :
11900
C_{T} = 2.33x + +1.86 y +10 xy
Determine the values of x 8 y which will give the least total cost. [8] b) Explain graphical and analytical general procedure for determining optimum conditions : [8]
Q9) a) Explain composite curves for following heat recovery system. [8]
Stream |
Type |
Supply temperature T, ^{0}Cs’ | Targettemperature
T_{t}, 0C |
A H MW | Heat capacity C _{p} MW.K^{1} |
^{R}1 |
Cold |
2O | 180 | 32 | 0.2 |
^{R}2 |
Hot |
250 | 40 | -31.5 | 0.15 |
^{R} Q |
Cold |
140 | 230 | 27 | 0.3 |
^{R} 4 |
Hot |
2OO | 80 | -30 | 0.25 |
b) What are the main factors in making the techno – economic feasibility study? Explain in detail. [8] |
QI 0) a) Obtain the iterative solution of an LP problem and solve for the maximum using the simplex method.
Maximize : f = x_{Y} + 3x_{2} Subject to : -x_{x} + x_{2} + x_{Q} = 1
x_{1} + x_{Q} + x_{R} = 2; x_{1} > 0 i = 1,…., 4 Where x_{y} x_{R} are slack variables. [8]
b) Write a note on optimum flow rate of cooling water in condenser. [8]
Draw 8 explain the plant layout 8 name the parts. [9]
A pilot plant consists six activities as tabulated below. Construct a network diagram and estimate EST, LST, EFT, LFT and floats. Mark the critical path and determine project duration. [9]
Activity | Pre – event | Sub – event | Duration (days) |
A | 1 | 2 | 5 |
B | 2 | 3 | 7 |
C | 3 | 5 | 6 |
D | 2 | 4 | 5 |
E | 4 | 5 | 4 |
F | 5 | 6 | 4 |
OR |
Q12) A chemical plant has sequence of following (A to N) activities. Show the expected time ‘T_{e}’ and latest allowable time ‘T_{L}’ for each activity in the diagram. Estimate the schedule completion time, variance and standard deviation. Also indicate the critical path. [18]
Activity | Pre-event | Sub-event | Optimistic Time ‘a’ | Most Likely Time ‘m’ | Pessimistic Time ‘b’ |
A | 1 | 2 | 6 | 11 | 16 |
B | 1 | 3 | 3 | 4 | 5 |
C | 3 | 4 | 3 | 5 | 7 |
D | 2,4 | 5 | 9 | 11 | 19 |
E | 4 | 6 | 3 | 5 | 6 |
F | 5 | 7 | 8 | 9 | 13 |
G | 7 | 8 | 19 | 23 | 30 |
H | 6 | 9 | 7 | 9 | 11 |
I | 5 | 10 | 9 | 10 | 17 |
J | 8 | 11 | 21 | 26 | 31 |
K | 10,11 | 12 | 13 | 17 | 21 |
L | 9,12 | 13 | 9 | 15 | 21 |
M | 13 | 14 | 4 | 5 | 9 |
N | 14 | 15 | 5 | 8 | 12 |
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