NODIA AND COMPANY. GATE SOLVED PAPER Chemical Engineering Plant Design and Economics. Copyright By NODIA & COMPANY

Size: px

Start display at page:

Download "NODIA AND COMPANY. GATE SOLVED PAPER Chemical Engineering Plant Design and Economics. Copyright By NODIA & COMPANY"

Randolph Evan Osborne
5 years ago
Views:

1 No part of this publication may be reproduced or distributed in any form or any means, electronic, mechanical, photocopying, or otherwise without the prior permission of the author. GATE SOLVED PAPER Chemical Engineering Copyright By NODIA & COMPANY Information contained in this book has been obtained by authors, from sources believes to be reliable. However, neither Nodia nor its authors guarantee the accuracy or completeness of any information herein, and Nodia nor its authors shall be responsible for any error, omissions, or damages arising out of use of this information. This book is published with the understanding that Nodia and its authors are supplying information but are not attempting to render engineering or other professional services. NODIA AND COMPANY B-8, Dhanshree Tower Ist, Central Spine, Vidyadhar Nagar, Jaipur Ph : enquiry@nodia.co.in

2 Year Q. 1 Two systems are available for compressing 6 m / h of ambient air to 10 bar. The first one uses a single stage compressor ^K 1 h and the second one uses a multistage compressor with inter-stage cooling ^K2h. Which one of the following statements is incorrect? (A) K 2 will have knockout pots in between the stages (B) Discharge temperature of K 1 will be higher than that of K 2 (C) K 2 will consume more power than K 1 (D) Cost of K 2 will be more than that of K 1 Q. 2 In a thin-walled cylindrical vessel of thickness t with inside radius r, the internal gauge pressure is p. The hoop stress and the longitudinal stress in the shell are σ h and σ l, respectively. Which one of the following statements is true? pr pr pr pr (A) σ h =, σ l = (B) σ h =, σ l = t 4t 4t t pr pr pr pr (C) σ h =, σ l = (D) σ h =, σ l = 2t t t 2t Year 2011 Q. 3 Fuel cell stacks are made of nine Membrane Electrode Assemblies (MEAs) interleaved between ten Bipolar Plates (BPs) as illustrated below. The width of a membrane electrode assembly and a bipolar plate are normally distributed with µ MEA = 015., σ MEA = 001. and µ BP = 5, σ BP = 01., respectively. The widths of the different layers are independent of each other. Which one of the following represents the correct values of ^µ stack, σ overall fuel cell stack width? (A) (51.35, 0.32) (B) (51.35, 1.09) (C) (5.15, 0.10) (D) (5.15, 0.11) stack h for the

3 Q. 4 A process plant has a life of 7 yr and its salvage value is 30%. For what minimum fixed-percentage factor will be depreciation amount for the second year, calculated by declining balance method be equal to that calculated by the straight line depreciation method? (A) 0.1 (B) (C) (D) Q. 5 A continuous fractionator system is being designed. The following cost figures are estimated for a reflux ratio of 1.4. Fixed cost including all accessories (Rs) for column # condenser # Operating cost (Rs/yr) for condenser cooling water 8# 10 6 reboiler # reboiler heating steam # The annualized fixed charge is 15% of the fixed cost. The total annualized cost (in Rs) is (A) 10. 8# 10 6 (B) # 10 6 (C) 15. 9# 10 6 (D) 315. # 10 6 Year 2010 Q. 6 The term knuckle radius is associated with (A) flat heads (B) torispherical heads (C) hemispherical heads (D) conical heads Year 2010 Q. 7 A reactor needs to be lined with a corrosion resistant lining. One type of lining costs Rs 5 lakh, and is expected to last for 2 year. Another type of lining lasts for 3 year. If both choices have to be equally economical with the effective interest rate being 18%, compounded annually, the price one should pay for the second type of lining is (A) Rs 6.1 lakh (B) Rs 6.5 lakh (C) Rs 6.9 lakh (D) Rs 7.6 lakh Common Data or Questions 8 and 9 : A plant produces phenol. The variable cost in Rs/ton of phenol is related to the plant capacity P (in ton/day) as P. The fixed charges are Rs per day. The selling price of phenol is Rs per ton. Q. 8 The optimal plant capacity (in ton/day) for minimum cost per ton of phenol, is (A) 101 (B) 141 (C) 283 (D) 422 Q. 9 The break even capacity in ton/day, is (A) 50 (B) 40 (C) 30 (D) 20

4 Year 2009 Q. 10 The total fixed cost of a chemical plant is Rs 10.0 lakh; the internal rate of return is 15% and the annual operating cost is Rs 2.0 lakh. The annualized cost of the plant, in lakh of Rs, is (A) 1.8 (B) 2.6 (C) 3.5 (D) 4.3 Year 2009 Q. 11 A column costs Rs 5 lakh and has a useful life of 10 year. Using the double declining balance depreciation method, the book value of the unit at the end of 5 year in lakh of Rs, is (A) 1.21 (B) 1.31 (C) 1.64 (D) 2.05 Q. 12 Match the equipment in Group I to the intervals in Group II. Group I Group II P. Centrifugal pump I. Baffle Q. Distillation column II. Impeller R. Heat exchanger III. Tray IV. Volute (A) P-II, Q-I, R-IV (B) P-II, Q-IV, R-III (C) P-I, Q-III, R-IV (D) P-IV, Q-III, R-I Year 2008 Q. 13 For the case of single lump-sum capital expenditure of Rs 10 crore which generates a constant annual cash flow of Rs 2 crore in each subsequent year, the payback period (in year), if the scrap value of the capital outlay is zero, is (A) 10 (B) 20 (C) 1 (D) 5 Q. 14 The relation between capital rate of return ratio (CRR), net present value (NPV) and maximum cumulative expenditure (MCE) is (A) CRR = NPV (B) CRR = MCE MCE NPV (C) CRR = NPV # MCE (D) CRR = MCE ^NPV+ MCEh Q. 15 To determine the performance of a compressor, a standardized test is performed. In the testing process, when the compressor is under operation, shut-off term signifies (A) maximum flow (B) zero flow (C) steady flow (D) intermittent flow

5 Year 2008 Q. 16 A reactor has been installed at a cost of Rs and is expected to have a working life of 10 yr with a scrap value of Rs The capitalized cost (in Rs.) of the reactor based on an annual compound interest rate if 5% is (A) (B) (C) (D) Q. 17 A cylindrical vessel with hemispherical ends is filled with water as shown in the figure. The head space is pressurized to a gauge pressure of 40 kn/ m 2. The vertical force F (in kn) tending to lift the top dome and the absolute pressure p (in kn/ m 2 2 ) at the bottom of the vessel are ( g = 98ms. /, density of water 3 = 1000 kg/ m ) (A) F = 83. 6, p = (B) F = 83. 6, p = (C) F = , p = (D) F = p = Year 2007 Q. 18 Select the most appropriate pump from Group II to handle each fluid flow given in Group I. Group I Group II P. Highly viscous fluid flow I. Piston pump Q. Fluid containing large amount II. Gear pump of abrasive solids III. Plunger pump IV. Centrifugal pump (A) P-II, Q-I (B) P-II, Q-IV (C) P-III, Q-IV (D) P-IV, Q-III Q. 19 A cylindrical storage tank can have a self-supported conical roof, (A) if its diameter is less than 20 m (B) if its diameter is more than 50 m (C) if the thickness of the roof is more than that of the cylindrical shell (D) whatever is the diameter

6 Year 2007 Q. 20 A pump has an installed cost of Rs and a 10 year estimated life. The salvage value of the pump is zero at the end of 10 year. The pump value (in Rs), after depreciation by the double declining balance method, at the end of 6 year is (A) 4295 (B) (C) (D) Year 2006 Q. 21 In a desalination plant, an evaporator of area 200 m 2 was purchased in 1996 at a cost of $ In 2002, another evaporator of area 50 m 2 was added. What was the cost of the second evaporator (in $)? Assume that the cost of evaporators scales as (capacity) The Marshall and Swift indices was in 1996 and in (A) (B) (C) (D) Q. 22 The mixing of rubber latex solution was studied in an unbaffled mixer in the laboratory. The mixer was equipped with a six blade turbine impeller. A tyre company scales this process up using a baffled tank. The baffled tank has 3 times the diameter of the lab scale mixer. It uses the same type of impeller operated at the same speed. The relevant shape factors are also the same. Assuming that laminar conditions prevail in both cases, the power requirement in the industrial scale mixer (A) is 3 times that of the lab scale mixer (B) is 9 times that of the lab scale mixer (C) is 27 times that of the lab scale mixer (D) cannot be estimated reliably due to the presence of battles Q. 23 Due to a 20% drop in the product selling price, the pay-back period of a new plant increased to 1.5 times that estimated initially. The production cost and the production rate remaining unchanged. If the production cost is C P and the new selling price is C S, then Cp/ CS is (A) 0.2 (B) 0.4 (C) 0.5 (D) 0.6 Q. 24 Obtain the optimal diameter of a cylindrical storage vessel of volume V. The curved shell costs C s (in Rs/m 2 ) and the flat top and bottom plates cost C P (in Rs/m 2 ), 13 / / (A) D Cs = b 4 V C π l (B) D 8VCS = c m 13 π C p (C) D VC S = c m 13 / (D) D = 4VC c m C π C P Q. 25 A sale contract signed by a chemical manufacturer is expected to generate a net cash flow of Rs per year at the end of each year for a period of 3 year. The applicable discount rate (interest rate) is 10%. The net present worth of the total cash flow, is Rs. (A) (B) (C) (D) P P / s 13

7 Year 2005 Q. 26 For a solid processing plant, the delivered equipment cost is Rs 10 lakh. Using Lang multiplication method, the total capital investment, in lakh of Rs, is (A) 46 (B) 57 (C) 100 (D) 200 Q. 27 The cost of drum dryer is Rs 10 lakh. the cost of drum dryer with double the surface area in lakh of Rs, is (A) 2# 10 (B) # 10 (C) # 10 (D) # Q. 28 The cost of distillation column in the year 2000 is Rs x, what is the cost of the column in Rs in the year 2010, given the cost indices for the years 2000 and 2010 are 480 and 520 respectively? (A) 520 b 2 x 480 l (B) b 480 x 520 l (C) 520 b x 480 l (D) 520 b 06. x 480 l Year 2005 Q. 29 The original value of an equipment is Rs The salvage value is Rs 500 at the end of its useful life period of 5 year. What is the asset value in Rs after 2 year by textbook declining balance method? (A) 3025 (B) 4010 (C) 5020 (D) 6050 Q. 30 The depreciable fixed cost is Rs 100 lakh. The average profit per year is Rs 15 lakh. The average depreciation cost per year is Rs 10 lakh. What is the payout period in years, if there is no interest charge? (A) 8 (B) 4 (C) 10 (D) 20 Year 2004 Common Data or Questions 31 and 32 : Fixed capital investment for a chemical plant is Rs 40 million with an estimated useful life of 6 year and a salvage value of Rs 4 million. The rate of interest is 15%, tax is 25% of the annual taxable income. In the first year of operation, the income from sales is Rs 20 million and manufacturing expenses are Rs 5 million. The plant depreciates on a straight line basis. Q. 31 The rate of return on investment is given by (A) 50% (B) 37.5% (C) 32% (D) 20%

8 Q. 32 The net present value (NPV) in million Rs at the start and at the end of the first year of operation is respectively given by (A) zero and 28.9 (B) 40 end 28.9 (C) 40 and (D) zero and Year 2003 Q. 33 Direct cost component of the fixed capital consists of (A) contingency (B) onsite and offsite costs (C) labour costs (D) raw material costs Q. 34 A series of equal payments (e.g., deposit or cost) made at equal intervals of time is known as (A) perpetuity (B) capital charge factor (C) annuity (D) future worth Q. 35 The variables required to be known in correlation used for estimating the horse power of a centrifugal gas compressor and hence its cost are (A) inlet pressure (B) compressor rpm (C) dilivery pressure (D) volumetric flow rate at inlet Year 2003 Q. 36 Two pumps under consideration for installation at a plant have the following capital investments and salvage values. Pump A: C 1 = Rs and C sal = Rs 3900 Pump B: C 1 = Rs and C sal = Rs Using capitalized cost, determine what should be the common life of the pumps for both to be competitive (economically equivalent) has been given like this only. Interest rate is 10% per annum. Maintenance and Operational costs are negligible. (A) 3 year (B) 5 year (C) 6 year (D) 8 year Common Data or Questions 37 and 38 : A process has fixed capital investment of Rs 150 lakh, working capital Rs 30 lakh and salvage value zero. Annual revenues from sales are Rs 250 lakh, manufacturing costs Rs 145 lakh and other expenses 10% of the revenue. Assume project life span of 11 year, tax life of 5 year and interest rate to be 10%. Tax rate is 40% and straight line depreciation, i.e., 20% per year, is applicable. Q. 37 Discounted value (to present time) of the profit before tax (for the total plant life period) in Rs is (A) 228 lakh (B) 400 lakh (C) 520 lakh (D) 660 lakh Q. 38 Discounted value of the depreciation benefit over the tax life in Rs is (A) 12 lakh (B) 24 lakh (C) 46 lakh (D) 60 lakh

9 Year 2002 Q. 39 The total investment in a project is Rs 10 lakh and the annual profit is Rs 1.5 lakh. It the project life is 10 yr, then the simple rate of return on investment is (A) 15% (B) 10% (C) 1.5% (D) 150% Year 2002 Q. 40 If an amount R is paid at the end of every year for n years, then the net present value of the annuity at an interest rate of i is n n ^1+ ih 1 (A) R ; i E (B) R ^1+ ih 1 > i 1 i n H ^ + h n (C) R^1 + ih (D) R n ^1 + ih Q. 41 A company has a depreciable investment of Rs which is depreciated in equal instalments in 2 year. Assume that the tax rate is 50% and interest rate is 10%. The net present value of tax that the company would have saved, if it had depreciated 2/3rd of the investment in the first year and the rest in the second year, is (A) zero (B) 250 (C) 375 (D) 500 Q A cylindrical pressure vessel of volume 6π m has to be designed to withstand a maximum internal pressure of 10 atm. The allowable design stress of the material is 125 Nmm / and corrosion allowance is 2 mm. The thickness of the vessel for a length/diameter ratio of 3 will be closed to (A) 5 mm (B) 6 mm (C) 8 mm (D) 10 mm Year 2001 Q. 43 An investment of Rs 100 lakh is to be made for construction of a plant which will take 2 yr to start production. The annual profit from operation of the plant is Rs 20 lakh. What will be the payback time? (A) 5 yr (B) 7 yr (C) 12 yr (D) 10 yr Q. 44 A perforated plate has holes of diameter d h arranged in a pitch p h. Each hole has tube of diameter d t passing through it. The ligament efficiency is given by p dd h t h - ph- d b h 2 l (A) (B) ph ph ph- dt ph- dh (C) (D) ph dh Q. 45 The ends of a cylindrical vessel can be closed by a head, which can be one of the four shapes. For the same thickness, choose the one which can withstand the highest pressure. (A) Flat plate (B) Hemispherical (C) Torispherical (D) Ellipsoidal

10 Year 2001 Q. 46 An investment of Rs 1000 is carrying on interest of 10% compounded quarterly. The value of the investment at the end of 5 year will be (A) 1000b l (B) 1000^ h 20 (C) 1000b l (D) 1000b l Q. 47 P is the investment made on an equipment, S is its salvage value and n is the life of the equipment in years. The depreciation for the mth year by the sum-ofyears-digits method will be m (A) P- S (B) 1 - P n b l S (C) m 2^n m+ 1h P- S n ^ h (D) ^P Sh nn ^ + 1h Q. 48 In a cylindrical vessel subjected to internal pressure, the longitudinal stress σ L, and the circumferential stress σ H, are related by (A) sh = 2sL (B) sh = sl L (C) sh = s (D) No relation exists 2 Year 2000 Q. 49 For a typical project, the cumulative cash flow is zero at the (A) end of the project life (B) break-even point (C) start-up (D) end of the design stage **********

11 ANSWER KEY (B) (D) (B) (C) (A) (B) (C) (B) (D) (C) (C) (D) (D) (A) (B) (A) (D) (B) (B) (B) (D) (C) (B) (B) (C) (A) (D) (C) (A) (B) (C) (D) (B) (C) (A) (D) (C) (B) (C) (B) (B) (D) (B) (C) (D) (B) (D) (A) (B)

Mechanical Design of Process Equipments

CH2357 Process Equipment Design I Mechanical Design of Process Equipments Dr. M. Subramanian Associate Professor Department of Chemical Engineering Sri Sivasubramaniya Nadar College of Engineering Kalavakkam