Plant Design and Process Control Flashcards
(86 cards)
1
Q
Feasibility of processes and establishment of profitability.
A
Process Evaluation
2
Q
Functionality assurance of a unit or process
A
Process Reliability
3
Q
Composition & mechanical properties of materials and equipment
A
Metallurgy
4
Q
Workers and environmental risks
A
Safety
5
Q
A
Control
6
Q
Atmospheric tanks - Operating pressure
A
0-5 psig
7
Q
Low-Pressure tanks - Operating pressure
A
5-15 psig
8
Q
Difference between measured value and setpoint
A
error
9
Q
Which industry produces electricity aside from its main product?
A
sugar industry
(recall bagasse)
10
Q
The act of joining together metals through heating the surfaces to melting point and uniting them to form one object
A
Welding
11
Q
Process required to release any locked up localized stress in vessels
A
Stress Relieving
12
Q
Process of locating weld defects by means of X-ray exposure
A
Radiographing
13
Q
Directly applicable to processes exhibiting linear dynamics behavior
A
Transfer Function
14
Q
Unwanted input that affects the control system’s output
A
Disturbance
15
Q
Can come from external interferences or electrical fields, instrumental wear&tear or any physical obstruction
A
Noise
16
Q
Electronic noise inside an electric conduction which is independent of applied voltage
A
Johnson Noise
17
Q
The process variables that are controlled.
A
Controlled variables
18
Q
The process variables that can be adjusted to keep the controlled variables at or near their set points.
A
Manipulated variables
19
Q
Process variables that negatively affect the controlled variables but cannot be manipulated.
A
Disturbance variables
20
Q
Occurs during important situations such as start-ups and shutdowns, correction of process disturbances, unusual process disturbances, feed stock and/or campaign changes, and planned transitions from one product grade to another.
A
Transient Operation
21
Q
Unaware of the whereabouts of the controlled variable, receives information on the measured disturbances and the set point and calculates the necessary corrective action to maintain the controlled variable at its set point in the presence of disturbances.
A
Feedforward Control
22
Q
Control based on the measurement of the controlled variable (process variable, PV) by a proper sensor and transmitting the measured signal to the controller.
A
Feedback Control
23
Q
Lug support is
A. the most suitable for thick vertical vessel.
B.same as bracket support.
C. provided usually for vessels of much smaller height than skirt supported vessels.
D. all (a), (b) and (c).
A
D. all (a), (b) and (c).
24
Q
The stress developed in a material without any permanent set is called the ___
A
Elastic Limit
25
In a heat exchanger, shell side fluid velocity can be changed by changing the tube ___
Layout and Pitch
26
Bracket supports are the most suitable for supporting __________ vessels.
thick walled vertical
27
Which of the following is an undesirable dynamic characteristic of an instrument ?
Reproducibility
Dead zone
Time lag
Static error
Time Lag
28
Which of the following is the dynamic characteristics of an instrument ?
Reproducibility
Sensitivity
Dead zone
Fidelity
Fidelity
29
Which of the following temperature measuring instruments need not touch the object whose temperature is being measured ?
Radiation/infrared pyrometer
Filled system thermometer
Mercury in glass thermometer
Thermo electric pyrometer
Radiation/infrared pyrometer
30
Radiation pyrometers as compared to thermocouples
-has a slower speed of response.
-can measure higher temperature.
-can't measure the temperature of moving objects.
-is more affected by corrosive atmosphere.
-can measure higher temperature.
31
__________ is undesirable in thermocouples used in industries,
Linear relation of emf to temperature
Corrosion resistance
Oxidation resistance
Non-linear relation of emf to temperature
Non-linear relation of emf to temperature
32
Which of the following thermocouples can measure the maximum temperature ?
Platinum-rhodium
Tungsten-molybdenum
Chromel-alumel
Iron-constantan
Tungsten-molybdenum
33
Which of the following controllers has maximum offset ?
P-controller
P-I controller
P-D controller
P-I-D controller
P-controller
34
Which of the following is not a differential pressure flow meter?
Rotameter
Flow nozzle
Orificemeter
Venturimeter
Rotameter
35
__________ controller has the maximum stabilising time.
P
PD
PI
PID
PI
36
Hot wire anemometer is used for the measurement of
-flow rates of fluids.
-flow rates of granular solids.
-very high temperature.
-thermal conductivity of gases.
-flow rates of fluids.
37
Which of the following is not a composition measuring instrument ?
-Thermal conductivity cell
-Mass spectrometer
-Polarograph
-Hot wire anemometer
-Hot wire anemometer
38
Property of fluid that converts kinetic energy to heat energy
fluidity
39
If a heat transfer equipment, dirt or scale may be accounted by introducing resistance called ______
fouling factors
40
A pipe conducting superheated steam is tagged with several layers of insulation. The rate of radial heat flow _______
equal through each layer
41
To increase the life of an incandescent lamp, it is ______
filled with argon gas
42
The net amount of money obtainable from the sale of used property over and above any charges involved in the removal and sale is called _____.
salvage value
43
Design based on giving the least cost per unit time or maximum profit per unit of production.
optimum economic design
44
One ingredient present in all baking powder is _____
Sodium Bicarbonate
45
A control structure with two feedback controller with the output of the primary controller changes the set point of the secondary controller whose output goes to the final controller.
cascade control
46
Which control system is used for multi-input, multi-output system?
model predictive control
47
The achievement of a temperature below that of the immediate surroundings is _____
refrigeration
48
Importance of SCADA
automation
49
Material of Construction:
Austenitic
Ferritic
Martensitic
Duplex
Austenitic: Most popular
Ferritic: cheap
Martensitic: requires less pre-heating and post-weld
Duplex: higher yield strength
50
How is fluctuation in the process controlled?
Equipping instrument with Integral Control
51
Temperature in which Reactor conditions cannot be controlled
Runaway temperature
52
Other term for Bulk Temperature
Mixing-Cup Temperature
53
The ratio of shear stress to shear strain is called
shear modulus
54
Which of the following material is seldom used for pressure vessel construction?
Rimmed still
Mild steel
Killed steel
Semi-killed steel
Rimmed still
55
Fresh water carrying pipelines in chemical industries are colored with color.
sea green
brown
yellow
red
sea green
56
Liquid/petroleum fuel storage tanks are built underground (as in case of petrol pumps), when the storage capacity is ______ less than kilolitres.
20
30
45
85
45
57
Lug support is
A. the most suitable for thick vertical vessel.
B. same as bracket support.
C. provided usually for vessels of much smaller height than skirt supported vessels.
D. (a), (b) and (c).
D. (a), (b) and (c).
58
With increase in the number of shell passes, the value of FT
A. increases
B. decreases
C. remains same
D. remains same, only if the number of tube passes does not change.
A. increases
59
Holes of a sieve tray are arranged in triangular pitch of _____ times the hole diameter.
A. 1.5 to 2
B. 2.5 to 5
C. 5 to 10
D. 10 to 15
B. 2.5 to 5
60
In case of a shell and tube heat exchanger, the minimum shell thickness for carbon steel (inclusive of corrosion allowance) depends on shell diameter and is in the range of _____ mm.
A. 3-5
B. 5-11
C. 8-15
D. 12-18
B. 5-11
61
The stress developed in a material without any permanent set is called the ____
ultimate stress
yield stress
elastic limit
breaking stress
elastic limit
62
In a shell and tube heat exchanger, the 'tube pitch' is defined as the
A. O.D. of the tube for square pitch.
B. shortest distance between two adjacent tube holes.
C. shortest centre to centre distance between adjacent tubes.
D none of these.
C. shortest centre to centre distance between adjacent tubes.
63
Which of the following is not a valid assumption in continuous binary distillation for calculating the number of equilibrium stages by Mc-Cabe-Thiele's method?
A. Sensible heat changes for vapor & liquid are negligibly small.
B. Reflux is not a saturated liquid.
C. Molar latent heat of the two components are equal.
D. Heat of mixing of normal liquid is assumed to be zero.
B. Reflux is not a saturated liquid.
64
The value of fouling factor depends upon the
A. characteristic of process fluid.
B. velocity of process fluid containing suspended solids.
C. suspended solids in the fluid.
D. all (a), (b) and (c).
D. all (a), (b) and (c).
65
In case of bubble cap distillation column of diameter greater than 1.2 metres, the cap diameter is roughly about _____ cms
A. 10
B. 20
C. 30
D. 40
A. 10
66
Tube side pressure drop in a 1-2 heat exchanger (for turbulent flow of fluids through the tubes) is about ____ times, that in a 1-1 heat exchanger having the same size & number of tubes and operated at the same liquid flow rate.
A. 2
B. 1/2
C. 4
D. 8
D. 8
67
To keep the power input constant for a stirred vessel operating under fully developed turbulent flow conditions (constant power number), if the impeller diameter is increased by 20%, the impeller speed should be decreased by a factor of
A. (1.2)^3/2
B. (1.2)^3/5
C. (1.2)^2/3
D. (1.2)^5/3
D. (1.2)^5/3
68
In a heat exchanger, shell side fluid velocity can be changed by changing the tube
A. layout
B. pitch
C. both (a) & (b)
D. neither (a) nor (b)
C. both (a) & (b)
69
Where does the maximum tensile strength occur in a thick cylindrical vessel subjected to internal pressure?
A. At the inner surface.
B. At the mid thickness of the cylindrical wall.
C. At the outer surface.
D. None of these.
A. At the inner surface.
70
It is not desirable to design correction factor, FT, of less than
A. 0.99
B. 0.95
C. 0.80
D. 0.55
C. 0.80
71
A rivetted joint does not fail by __________ of rivets.
A. Tearing
B. Shearing
C. Tearing of the plate across a row
D. None of these
D. None of these
72
Triangular pitch tube layout as compared to square pitch in a shell and tube heat exchanger
A. permits the use of less tubes in a given shell diameter.
B. facilitates comparatively easier external cleaning because of large clearance.
C. permits the use of more tubes in a given shell diameter.
D. both (b) and (c).
C. permits the use of more tubes in a given shell diameter.
73
Bracket supports are the most suitable for supporting ___ vessels.
A. thick walled vertical
B. horizontal
C. thin spherical (e.g. Horton sphere)
D. none of these
A. thick walled vertical
74
In a multi-pass shell and tube heat exchanger, the shell side cross flow area does not depend upon
A. baffle spacing
B. clearance
C. pitch
D. none of these
D. none of these
75
Two iron pipes of the same nominal diameter but different schedule numbers will have the same
A. inside diameter
B. outside diameter
C. wall thickness
D. none of these
A. inside diameter
76
Lessing ring is formed by the addition of a partition across the centre of a raschig ring, which results in an area increase of about __ percent.
.
A. 5
B. 20
C. 35
D. 55
B. 20
77
In chemical process equipment, the conical bottom heads used, usually has an apex angle of
A. 20°
B. 40°
C. 60°
D. 80°
C. 60°
78
Smaller sized packings are generally dumped to the packed columns, and the large ones of size greater than ____ mm are stacked individually, which provides better control over bed porosity and offers lower gas pressure drop.
A. 25
B. 50
C. 75
D. 150
C. 75
79
Correct use of 'factor of safety' is very important in equipment design. It is defined as the ratio of the
A. ultimate stress to breaking stress.
B. ultimate stress to working stress.
C. working stress to ultimate stress.
D. none of these.
B. ultimate stress to working stress.
80
The operating velocity in the absorption tower is usually 40-50% of the flooding velocity. Packed absorption towers are normally designed for a pressure drop of about ____ mm of water column per meter height of packing.
A. 1-5
B. 20-40
C. 100-150
D. 1000-1500
B. 20-40
81
In perforated plate towers, the
A. hole sizes may be around 1/8" or 3/16".
B. total hole area may be around 6 to 15% of tower cross- sectional area.
C. pressure drop is less compared is similar bubble cap towers.
D. all (a), (b) and (c).
D. all (a), (b) and (c).
82
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
D. Ellipsoidal
83
Wall thickness of schedule 40 pipe as compared to that of schedule 80 pipe is
A. more
B. less
C. same
D. either (a) or (b); depends upon the I.D. of the pipe
B. less
84
Pick out the wrong statement pertaining to the design of a basket type evaporator.
A. It is used for high viscosity liquor having large rate of scaling.
B. The tube bundle is suspended on bracket.
C. There is no central downtake.
D. Downtake is formed by the annular space between the bundle and the shell.
A. It is used for high viscosity liquor having large rate of scaling.
85
Speed of the drum of the rotary vacuum filter normally ranges from rpm.
A. 0.1 to 2
B. 5 to 7
C. 3 to 8
D. 8 to 15
A. 0.1 to 2
86
A stuffing box is used for
A. absorbing the contraction/expansion of pipeline due to temperature changes.
B. prevention of fluid leakage around moving parts.
C. facilitating smooth opening and closing of a valve.
D. reducing the resistance of fluid flow.
B. prevention of fluid leakage around moving parts.
