Download SGBAU (Sant Gadge Baba Amravati university) B-Tech/BE (Bachelor of Technology) 7th Sem FPOPC Petro Mass Transfer Previous Question Paper
11056: Mass Transfer. ' 7 CT 01
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P. Pages : 3 AW - 3388
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Time : Three Hours Illomzemzll? Max. Marks : 80
Notes : 1 Answer three question from Section A and three question from Section B.
2 Due credit will be given to neatness and adequate dimensions.
3. Assume suitable data wherever necessary.
4. Diagrams and chemical equations should be given wherever necessary.
5 Illustrate your answer necessary with the help of neat sketches.
6 Use of pen Blue/Black ink/re?ll only for writing the answer book.
SECTION - A
l a) Explain the mechanism of absorption based on two ?lm theory of mass transfer. 7
b) Gas from a petroleum distillation, has its concentration of H2 S reduced from 0.03 Kmol 7
H2 S per Kmol of inert hydrocarbon gas to 0.1%. of this value by scrubbing with
triethanolamine water in a counter current tower operating at 300K and at atmospheric
pressure. The equilibrium relation for the solution may be taken as Ye = 2X.
The solvent enters the tower free of H2 S and leaves containing 0.013 Kmol of H2 S
per Kmol of solvent. If the ?ow of inert gas is 0.015 kmol/m2 -sec of tower cross section,
estimate height of absorber and the number of transfer units (N06 ). The overall coef?cient
for absorption KG a may be taken as 0.04 Kmol/m3 -sec- Unit driving force.
OR
2 a) Discuss interphase mass transfer between gas and liquid phase and the overall mass transfer 7
coe?icient.
b) Explain the concept of IlETP and HTU in continuous equipment fob absorption and how to 7
estimate the total height of the absorption column, when the equilibrium curve is a straight
line.
3 a) What is differential distillation? Derive an expression for Rayleigh?s equation. 6
b) Explain McCabe-Thiele method to determine number of theoretical plates in a distillation 7
column.
OR
4 a) Why re?ux ratio is necessary in fractionation? Explain its importance. v 6
b) Discuss the effect of feed temperature on the number of plates in a distillation column. 7
Develop expression for ?q? line and indicate the effect on number of plates in terms of ?q
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5. a)
b)
6. a)
b)
7. .1)
b)
8. u)
b)
9. a)
b)
10. a)
b)
Explain the types of ternary systems and criteria of solvent selection in liquid-liquid
extraction.
Exalain the different types of membranes and the application of membrane separation in
paper industries.
OR
Acetaldehyde (5%) is in solution in toluene and is to be extracted with water in a ?ve stage
co-current unit. If 25kg of water is used per 100kg feed, determine the amount of
acetaldehyde extracted and the ?nal concentration. The equilibrium relation for the system
is given as:
Ye = 2.2x.
Where Y- Kg ot?acelaldehydezkg 01? water.
X - kg of acetaldehydefkg 01' toluene.
How are membranes characterized and discuss the application of membrane separation in
biotechnology.
SECTION - B
What is leaching and discuss the parameters on which rate of leaching depends?
Derive an expression for the ?fraction unextracted' for single stage multi contact. Washing
system of insoluble salids retaining suf?cient solute in it.
OR
What is the criteria 01? solx :nt selectron in soliJ-liquid extraction? Explain.
A plant produces lOIJRg?sL-c of titanium dioxide (TiOZ) pigment which must be 99.9%
pure when dried. The pigment is produced by precipitation and the material as prepared is
contaminated with 1kg of salt solution containing 0.55kg of salt per kg of pigment. The
material is washed counter currently wilh water in a number of thickeners arranged in series.
How many thickness will be required if water is added at a rate of 200 kg/sec and the solid
discharged from each thickener removes 0.5kg of solvent per kg ofpigment.
Explain Mier?s supersaturation criteria and nucleation in crystallization process.
What will be the yield of N82 32 03 - 5H: 0 if IOOkg of 48% solution of Naz 82 03 are
cooled to 20?C. The solubility of Na: 32 03 at 20?C is 70 parts per 100 parts of water.
Molecular weight of N33 S: 03 =158.
OR
How crystal growth oecurs?.? What are the parameters which can affect the crystal growth?
Disc uss the classi?cation of crystallization equipments and explain the operation of any
one.
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12.
a) How to calculate drying rate and explain constant rate and falling rate drying periods.
b) Explain the operation of a rotary dryer and its design procedure.
OR
a) Test drying of food was carried out in an insulated may. The temperature of the drying air
was 60?C and the dew point 20?C. The dry weight of the material was 3.765kg and the
surface area 0.186m2 . Test data are:
Data: Weight of humid material at di?'ercnt dryin lime.
t hrs. 0 0.4 0.8 1.4 2.2 3.0 4.2 5.0 7.0 9.0 12.0 25.0
weight 4.94 4.88 4.8 4.67 4.55 4.4 4.21 4.15 4.09 3.97 3.955 3.955
(G)kg ~
Determine the equilibrium moisture content and the drying rate as a function of moisture
content in both rates.
b) What are the various theories of drying? Explain in details.
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This post was last modified on 10 February 2020