1. 1
Chapter 1
INTRODUCTION
Vegetable oils has been used in areas involving chemical processing, and also for
direct consumption. With the rapid rise in conversion of non-vegetarian to
vegetarian process, an increase in usage of vegetable oil is seen. It also helps in
contributing to some extent to prevent environmental degradation. There are
various ways of extracting vegetable oils like by process of fluidization, solvent
extraction, mechanical expulsion etc. Here extraction is done by fluidization
process using a fluidized bed extractor.
FLUIDIZATION:
When a liquid or gas is passed at very low velocity up a bed of particles, the
particles do not move and this is the condition of fixed bed. If the velocity is
steadily increased, the pressure drop and drag eventually starts to increase on the
particles, as a result particles move away from each other some vibrate and move
in restricted regions now this is the condition of expanded bed. On further
increasing the velocity, the frictional force between the solid and fluid particles just
counter balances weight of the particles, and this condition is known as minimum
fluidization or incipient fluidization. This is noted that at condition of fluidization,
bed of suspended particles behave as either a fluid or gas.
TYPES OF FLUIDIZATION:
Fluidization is mainly of two types i.e. Particulate fluidization and aggregative
fluidization. Particulate fluidization occurs when the solid and fluid density
difference is not much and the solids are smaller in size. In this fluidization the
fluid velocity required to fluidize the bed is not much (example- liquid-solid
systems).
Aggregative fluidization occurs when the solid and fluid density difference is more
and solids are larger in size. In this fluidization the fluid velocity required to
fluidize the bed is quite high (example- gas-solid systems). In this case when
fluidization occurs then bubbles form in between the solids because of the large
particle size and high liquid velocity. These bubbles carry little or no solid particles
with them. When these bubbles rise from the bed then they eventually break at the
surface of bed. The superficial fluid velocity in which fluid bubbles form is called
the minimum bubbling velocity. Generally a bubbling fluidized bed is considered

2. 2
to be undesirable for industrial application. (Narayanan et.al, 2009)
THREE PHASE FLUIDIZED BED:
Simply it can be stated as a bed of particles suspended in a column, when gas or
liquid is inserted. Generally a three phase exists which is solid-liquid-gas under
three phase operations. It finds its immense use in wastewater treatment, certain
chemical and bio-chemical industries.
MODES OF OPERATION OF THREE PHASE:
There are several types of modes of operation which is due to difference in flow of
solid-liquid-gas in different directions, the velocity factor etc. Mainly these are
categorized into three main division:
1. Parallel mode of operation with liquid as the continuous phase.
2. Parallel mode of operation with gas as the continuous phase.
3. Inverse three phase fluidization.
ADVANTAGES OF THREE PHASE:
Three phase fluidization acts as reactors and it overcomes some of the problem that
may occur in conventional reactors. Some of them are pointed as:
1. Formation of local hotspots is prevented.
2. Smooth, localized flow with simple and automatically controlled operation.
3. Suitable for large scale operation.
4. High turbulence is achieved, better mixing facility, flexibility.
5. Heat recovery and temperature control.
6. It creates more gas-liquid interfacial area due to better gas phase
distribution.
DISADVANTAGES OF THREE PHASE:
1. As the solids are rapidly mixed in the bed, it leads to non-uniform residence
time of particles in reactor.

3. 3
2. Possibility of entrapment of solid particles in best becomes more because of
high turbulence and mixing, size of particles is reduced.
3. Inefficient contact system due to bubble formation in reactor.
USES IN VARIOUS FIELDS:
1. Hydrogenation of oil.
2. Hydro desulphurization of oil.
3. Coal liquefaction by H-coal process.
4. Fischer-tropsch process.
5. Non-catalytic coking of petroleum residues.
6. Catalytic oxidation of naphthalene to phthalic anhydride.
7. Contacting bed used for flue gas desulphurization process.
8. Treatment of waste water by bio-oxidation process.
9. Mass transfer operations.
10. Methanol processing bio-chemical industries.
11. Pharmaceutical industries.
FLUIDISED BED EXTRACTOR:
Fluidized-bed extractor has the ability to process large volumes of fluid. A
fluidized bed extractor is a type of extractor that can be used to carry out various
types of multiphase reactions.
A laboratory-scale fluidized bed extractor was designed and fabricated for the
purpose of the present study. The fluidized bed extractor is a thick boro-silicate
glass tube (SS compatible) of 100-mm inside diameter, 3-mm wall thickness, and
2000-mm length. The tube is fitted with a perforated stainless steel gas distributor.
The distributor has 2-3mm diameter holes on a triangular pitch which gives 13%
free area. A fine mesh of 0.1 mm is fixed over the distributor to arrest the flow of
fine particles through the perforations. The fluidized bed is heated by an electric
furnace, and the bed temperature is controlled by a computer based thermocouple
(MOC-Iron/Constantan).
The solid substrate in the extractor is typically supported by porous plate
known as a distributor. The fluid is then through the distributor up through the
solid material. At lower fluid velocities the solids remains in the place while the
fluids passes through the voids in the material.

4. 4
FLOW REGIME IN FLUIDISED BED EXTRACTOR:
With several operating variables in fluidized bed extractor, it is important to have
information about flow regimes in order to attain a stable operations separation
between flow regimes is yet not clear but still there are some patterns to be
differentiated and they are:
1. Dispersed bubble flow:
 Low gas velocities.
 High liquid velocities.
 Small uniform size of bubbles occur.
2. Discrete bubble flow:
 Low liquid and low gas velocities occur.
 Bubble size is small.
3. Coalesced bubble flow:
 Low liquid and intermediate gas velocity occur.
 Bubble size is big.
4. Slug flow:
 Bubbles in the shape of large bullets and diameter equal to that
of column diameter.
5. Churn flow:
 Resembles the slug flow regime.
 With an increase in gas flow, an increase in downward liquid
flow is observed.
6. Bridging flow:
 Intermediate regime between annular and churn flow.
 An interesting factor is solid and liquid forms “bridges” in
reactor that breaks and re-forms.
7. Annular flow:
 At high gas velocity, a continuous gas phase develops in the
core of the column.

5. 5
VARIABLES AFFECTING THE PROCESS:
Certain variables affecting quality of fluidization. They are:
1. Fluid flow rate: Enough flow rate must be provided in order to keep
particles in suspension but it should be taken care to avoid bed from
channeling that generally occurs at very high fluid velocity.
2. Fluid inlet: Inlet should be designed in such a way that it provides uniform
distribution of fluid entering the bed.
3. Gas, liquid and solid densities: When the relative densities of gas, solid
and liquid are closer, then it is easiest to maintain smooth fluidization.
4. Particle size: Variation in particle size plays a key role in promoting an
efficient fluidization. Mainly it is recommended to have a wide range of
particle size rather than have uniform sizes for efficient mixing.
5. Bed height: As the bed height is increased, it is difficult to maintain smooth
and efficient fluidization.
6. Temperature: With an increase in temperature to a limited range, the
extraction efficiency also increases.
MINIMUM FLUIDIZING VELOCITY:
Fluidization will be considered to begin at the gas velocity at which the weight of
the solids gravitational force exerted on the particles equals the drag on the
particles from the rising gas. If the gas velocity is increased to a sufficiently high
value, however, the drag on an individual particle will surpass the gravitational
force on the particle, and the particle will be entrained in a gas and carried out of
the bed. The point at which the drag on an individual particle is about to exceed the
gravitational force exerted on it is called the maximum fluidization velocity.
Experimental data of minimum fluidization velocity in the cylindrical and conical
fluidized bed under both liquid-solid and gas-liquid-solid fluidized conditions were
obtained based on the pressure drop vs. the superficial velocity curve. For the
liquid-solid cylindrical bed, the experimental data were compared with the Ergun
equation.

6. 6
INTRODUCTION TO SOYABEAN:
Soyabean is one of the major food crops worldwide because of its favorable
agronomic characteristics, high quality edible oil products, high quality animal
feed meal, and it is available at reasonable prices. Figure 1.1 shows the production
of soyabeans in various countries. The use of soyabean and soyabean related
products started around about the 1920’s in the United States, with less around 50
million MT being produced in 2007. This has increased to about 80 million MT in
2011. Figure 1.1 gives a general idea of how the soyabean oil production has
grown in the past decade.
Figure 1.1 World Soyabean Production.
Soyabean Composition:
Commercial soyabeans consists of about 20 % oil, with the rest constituting of
proteins, carbohydrates, fatty acids, inorganics and minerals, amino acids,

7. 7
phospholipids, and sugar. The approximate composition of soyabeans is
summarized in Table 1.1.
Component Weight Percent
Moisture 11.0
Protein 37.9
Fat 17.8
Fiber 4.7
Ash 4.5
Table 1.1 Soyabean Composition.
Figure 1.2 Soyabean Seeds.

8. 8
Carbohydrates:
Whole soybeans consist of about 35% carbohydrates, of which about 20 % is
insoluble carbohydrate. Stachyose, raffinose, glucose and sucrose form the
majority of the carbohydrates found in soybeans. Sugar (sucrose and glucose) is a
major raw material used in the manufacture of ethanol. This high content of
carbohydrates can also be put to use, by either extracting the sugars for edible use
or for commercial chemical manufacture.
Fatty Acids:
Soybeans primarily consist of triglycerides and triglecerols, with linoleic, linolenic
and oleic acids forming the majority. Saturated fatty acids are the component that
contribute to bodily fats in humans and hence are considered to be anti-nutritional
when consumed. The low content of saturated fatty acids is what makes soybean
oil popular as an edible oil.
Minerals & Inorganics:
Minerals form a very important part of the human diet and a person requires a
minimum amount of minerals in his daily diet. Hence, the mineral content of
soybeans is very important. Soyabeans consist of about 2 % potassium, 0.5%
sodium, 0.3 ~ 0.7% phosphorous with trace quantities of magnesium, calcium and
iron.
Proteins:
Soyabean meal is a very popular animal feed because of its high protein content.
Proteins constitute about 40% of soyabeans. Soy proteins consist of amino acids in
varying compositions, trypsin inhibitors and haemagglutinins which are
nutritionally important. Soy proteins are generally heat inactivated, which is as a
major constraint when processing soy oil. Processing temperatures higher than
100o
F generally tend to depreciate the quality of the soy oil produced.
Physical Properties of Soyabean:
The physical properties of soyabeans are a function of various parameters, which
include climatic conditions during growth, oil composition, temperature and

9. 9
pressure, molecular weight, fatty acid chain length, etc. The physical properties of
soybean are critical parameters which have to be considered when designing soy
processing equipment and processes such as extractor, dryer, etc. The physical
properties of soy oil are listed in Table 1.2.
Property Value
Specific Gravity at 25o
C 0.9175
Refractive Index 1.4728
Viscosity at 25 o
C (cP) 50.09
Solidification Point (o
C) -10 ~ -16
Specific Heat at 19.7 o
C (Cal/g) 0.458
Heat of combustion (Cal/g) 9478
Flash Point (o
C) 328
Fire Point (o
C) 363
Table 1.2 Physical Properties of Soyabean Oil
PROPERTIES OF SOLVENT:
A good extraction solvent should have a strong solubilizing capability for the
compound of interest, it should be immiscible or only weakly miscible with the
matrix solvent (the first solution or mixture containing the compound from its
natural source, e.g., water/ether. water/ chloroform, etc.). If possible the extraction
solvent should be non-flammable, non-toxic or of low toxicity, reasonably volatile,
and of low eco-impact. Inexpensive and available, of high purity, and shelf stable.
If one is determining the compound of interest by UV/Vis spectrophotometry or
fluorescence, the solvent should have extremely low absorbance or emission at the
wavelength of analysis.
Hexane is generally used as a solvent for extraction purpose due to its physical
and chemical properties. But, hexane is highly flammable and is also known to

10. 10
cause nervous damage to people exposed to it in sufficient quantities. Using
hexane as solvent also results in a solvent loss of about 1 ~ 8 lit. / Metric ton of
seeds processed. All of these issues combined with the necessity of severe
extraction (temperature and pressure) conditions and environmental concerns have
resulted in renewed interests in using an alternative solvent for extraction. Typical
solvents of interest are alcohols and supercritical fluids such as carbon dioxide.
Alcohols require a high solvent to feed ratio, but solvent recovery becomes an
issue as alcohols usually tend to form an azeotrope when mixed with water.
Acetone is one of the chemicals, which satisfies most of the characteristics
required for a good solvent. The only disadvantage of using acetone in comparison
to hexane it requires a higher solvent to feed ratio. Table 1.3 compares the
properties of acetone and hexane and highlights important parameters such as the
flash point, the boiling point, toxicological data, and fluidic properties which
would suggest that acetone could be a good substitute.
Parameter n-Hexane Acetone
Density of liquid @ 60 F
(lb / cu. ft.)
41.5 .791
Vapor Pressure @ 70 F
(Psia)
2.5 3.480
Boiling Point @ 1 atm (F) 156 133
Flash Point (F) -10 1.42
Oil Solubility Depends on
temperature
Depends on
temperature
Toxicological Limit(ppm) Inhalation: 12000 Inhalation: 5000
Inhalation (ppm/hr), Oral
(mg/kg)
Oral: 28700 Oral: 6500
Explosion Limit (%) 1.2 ~ 7.7 2.6 ~ 3
Table 1.3 Solvent Properties.

11. 11
As hexane have certain disadvantages such as highly flammable etc. it can be
blend with other solvent like acetone, propane and alcohols to give better
extraction efficiency. On blending with other solvents the properties of n-hexane
will be change to certain limit which is good for extraction purpose and recovery
percentage also increases.

12. 12
Chapter 2
LITERATURE REVIEW
The first fluidized bed was first found by Winkler in 1921 and industrial
fluidized bed was first used as large-scale in Winkler gasifier in 1926 (Kunii and
Levenspiel, 1991). Fluidized bed catalytic cracking of crude oil to gasoline (FCC)
was commercialized in 1942, and is still the major application of fine-powder
fluidization. Several catalytic applications such as acrylonitrile synthesis, phthalic
anhydride and Fischer-Tropsch synthesis of liquid fuels from coal-based gas
extended the range following the Fluidized bed catalytic cracking. Lurgi
commercialized the circulating fluidized bed (CFB) in the 1970’s, for coarse
powders, which would operate above the terminal velocity of all the bed particles.
Polyethylene was produced in a fluidized bed, and the technology is widely used in
industry.
Commercialization of circulating fluidized bed was done in 1980’s for the
combustion and production of polypropylene in fluidized beds. New areas of
application in fluidization were production of semiconductors and ceramic
materials by chemical vapour deposition and in biological applications the use of
liquid fluidized beds.
The successful design and working of a gas-liquid-solid fluidized bed system
depends on its ability to accurately predict the fundamental characteristics of the
system mainly the hydrodynamics, the mixing of individual phases, and the heat
and mass transfer characteristics. Three-phase fluidized beds are also often used in
physical operations. Here three phase fluidized bed extractor is used to extract soya
oil from soyabean seeds by using solvents like n-hexane and acetone for different
particle size, extraction time and temperature. Based on the different parameters,
the efficiency of extraction is determined.

13. 13
Chapter 3
EXPERIMENTAL SETUP
The fluidized bed assembly consists of three sections, viz., the test section, the
gas-liquid distributor section, and the gas-liquid disengagement section. Fig. 3.3
shows the schematic representation of the experimental setup used for extraction of
soya oil. Fig. 3.4 gives the photographic representation of the fluidized bed
extractor. The test section is the main component of the fluidized bed where
fluidization takes place. It is a vertical cylindrical Plexiglas column of 100 mm
internal diameter and 2000mm height. The gas-liquid distributor is located at the
bottom of the test section and is designed in such a manner that uniformly
distributed liquid and gas mixture enters the column. The setup consist of a
thermocouple made of iron-constantan which is connected to computer based
control system used to measure the temperature during the experiment. An electric
heater with temperature controller of 1/2 KW is wrapped around the column for
heating purpose. Other components with the specification and photographs are
mentioned below.
 Main Column:
Height of column: 2000mm
Diameter of column: 100mm
MOC: Glass/ SS compatible with working condition
 Distributor:
Diameter of hole: 2-3 triangular pitch as per design matching with expt.
Diameter of plate: Fit to column
 Electric Heater:
(With Temperature controller)
Capacity: ½ KW
Type: Around the column

14. 14
 Liquid Manometer:
Model: U Type
Type: Wall Mounted
Range: 500-0-500mmhg
Glass: Borosilicate Toughened
 Thermocouple:
Type: “J”
MOC: Iron/Constantan
 Condenser:
Type: Horizontal Shell and Tube Type
Size & Length: As required
MOC: SS-304
Insulation: 25mm thick glass wool insulation
 Reservoir:
Capacity: 25Litre
MOC: SS-304
Accessories: Liquid level indicator, Drain valve
 Compressor with pressure indicator:
Capacity: 0-5 kg/cm2
Motor: 1/3 HP
 Dosing Pump:
Maximum head: 5meter
Flow rate: 800LPH

15. 15
 Rotameter:
Capacity: 0-3000LPH
Solvent: n-Hexane
 Control Panel:
- Energy meters
- Necessary display meters for Instrumentation input and output indication
- ON/OFF switches and indicator lamps for all the electrical items etc.
 Mimic Diagram of Experimental set-up:
It should be Suitable and Symmetrical
 Specifications for Software:
- Equipment should be laboratory size and Computer liking arrangement is
to be provided and suitable PID SCADA software are to be provided.
- Software for experimentation, ID control, DATA logging, Trend Plot,
Offline analysis, Display and Printing etc.
- Software’s Instruction manual for Software Operations and
Experimentation etc.
Figure 3.1: Distributor plate Figure 3.2: Pump

16. 16
Figure 3.3: Schematic Representation of Experimental Setup.

17. 17
Figure. 3.4: Photographic Representation of Fluidized Bed
Extractor.

18. 18
Figure 3.5: Rotameter
Figure 3.6: Compressor

19. 19
Chapter 4
EXPERIMENTAL PROCEDURE
The experiment was carried out using crushed soya bean seeds as solid particle,
n-hexane and blend of n-hexane and acetone as liquid (solvent) and compressed air
as fluidizing medium. The soyabean seeds are crushed to particle size of 3 ~ 4 mm
using crushing equipment such as ball mill and then separated uniformly by using
mesh screen. The temperature is controlled by using computer based PID
controller which measure as well as helps in controlling the temperature during the
conduction of experiment.
At a time one parameter is varied and other parameters are fixed and efficiency
of extraction is determined. Efficiency of extraction is giving by:
Efficiency of Extraction (η)
=
𝒘𝒆𝒊𝒈𝒉𝒕 𝒐𝒇 𝒔𝒆𝒆𝒅𝒔 𝒃𝒆𝒇𝒐𝒓𝒆 𝒆𝒙𝒕𝒓𝒂𝒄𝒕𝒊𝒐𝒏−𝒘𝒆𝒊𝒈𝒉𝒕 𝒐𝒇 𝒔𝒆𝒆𝒅𝒔 𝒂𝒇𝒕𝒆𝒓 𝒆𝒙𝒕𝒓𝒂𝒄𝒕𝒊𝒐𝒏
𝒘𝒆𝒊𝒈𝒉𝒕 𝒐𝒇 𝒔𝒆𝒆𝒅𝒔 𝒃𝒆𝒇𝒐𝒓𝒆 𝒆𝒙𝒕𝒓𝒂𝒄𝒕𝒊𝒐𝒏
= 𝑪𝒐 − 𝑪𝒕/𝑪𝒐
PROCEDURE:
 Add crushed soyabean seeds into the column using funnel from the feed
point. Make sure that the crushed seeds size should not be less than the hole
diameter of distributer plate.
 Fill the feed tank with solvent up to 60-70% of the capacity or as per as
requirement.
 Keep the recirculation hand valve of a pump fully open.
 Start the compressed air flow for fluidization and adjust the velocity
according to the requirement.

20. 20
 Switch the pump for transfer of solvent to the column and recirculating to
tank with minimum flow rate. Adjust the flow rate using rotameter using
recirculation hand valve.
 Switch on the electric heater around the column and start heating of fluid in
the column up to desired temperature (set point through computer controlled
HMI).
 Adjust the inlet flow rate of the solvent to minimum fluidization velocity
through rotameter.
 Run the software.
 Set the controller in auto mode and set the solvent temperature to desired
value.
 Run the system according to the desired experiment.
SHUT-DOWN PROCEDURE:
 Switch off the Heating supply to heater around the column.
 Switch off the feed Pump of solvent supply (P-1) and stop circulation by
hand valves.
 Switch off the air supply to the compressor and make sure there is no back
flow to the compressor.
 Close the water supply to condenser.
 The column can also be drained with the help of the drain valve provided at
the bottom of the column.
 Switch of the main supply of the panel.
The sample is collected from the sample point and it is simple distillated
at boiling point temperature of the solvent in order to remove the solvent
completely from the oil. The distillate oil is then examined in the UV
spectroscopy meter to find out the actual concentration of soya oil in the
product.
The spend seeds are collected and weight. The extraction efficiency can
be calculated by using the weight of processed seeds by using above
mentioned formula.

21. 21
Figure 4.1 Temperature Controller Software.

22. 22
Scope of Experiment:
S. No. Material Dp (mm) ρ ( kg/m3
)
1. Soyabean seed 2-2.5 652
2. Soyabean seed 2-5 660
3. Soyabean Flakes 12-15
(thickness =
.35mm)
264
Table 4.1 Properties of Material, Soyabean
S. No. Fluidizing
medium
Viscosity (mPa.s) Density (g/mL)
1. n-Hexane 0.28 at 30o
C 0.6548
2. n-Hexane 0.19 at 70o
C 0.6548
3. Acetone 0.402 at 30o
C 0.7910
4. Acetone 0.304 at 56o
C
5. 50% n-Hexane
+ 50%Acetone
0.352 at 30o
C 0.7229
Table 4.2 Properties of Fluidizing Medium
Superficial Gas Velocity 0-3 cm/s
Superficial Liquid Velocity 0-10 cm/s
Static Bed Heights 15.4 cm , 15.6 cm , 21.4 cm , 26.4 cm ,
31.4 cm
Temperature 28o
C - 65o
C
Table 4.3 Properties of Operating Conditions.

23. 23
Chapter 5
RESULT AND CONCLUSION
The method of fluidized bed extractor is used to extract soya bean oil from soya
bean seeds by using n-hexane and blend of n-hexane and acetone and compressed
air as fluidizing medium. Effects of gas phase velocity, extraction time temperature
and fluidized solid types on the extraction efficiency in the extractor have been
studied by manipulating different parameters to find the optimum point between
efficiency and the time of extraction of soya bean oil. The result of the study are as
follows:
 While studying the relation between the efficiency and the time of extraction
of oil when the gas velocity is kept constant at 3cm/sec, liquid velocity is
kept at 10 cm/sec, temperature at 50o
C and varying the type of particle like
flake, cracker 1 and cracker 2 of sizes 12-18 mm, 2-5 mm, 2-2.5 mm in
diameter. It is found that with increasing the extraction time there extraction
efficiency increases.
 When the gas velocity is kept constant at 3cm/sec, liquid velocity is kept at
10 cm/sec, particle size is kept constant at 12-18 mm in diameter and 0.35
mm in thickness and varying the temperature from 28o
C to 65o
C. It is found
that with increasing the extraction time, extraction efficiency is increased.
 When the temperature is kept constant at 50o
C, liquid velocity is kept at 10
cm/sec, particle size is kept constant at 12-18 mm in diameter and 0.5 mm in
thickness and varying the gas velocity from 0 to 5.0 cm/s. It is found that
with increasing the extraction time, extraction efficiency is increased.
 When the gas velocity, liquid velocity, particle size, the temperature are
varied all together, it is found that maximum extraction is reached at certain
point called optimum point where there is maximum recovery of solvent.
Due to defects in the equipment the optimum point where efficiency is
maximum can’t be determined.

24. 24
 With the use of blend of solvent (n-hexane and acetone) extraction
efficiency lies somewhat in the middle range but the recovery of solvent is
increased which in turn reduce the cost of extraction
CONCLUSION:
From the literature, it is revealed that fluidized beds are beneficial for efficacious
gas-liquid-solid contacting process and can be used for waste water treatment,
catalytic and non-catalytic reactors and in various chemical and bio-chemical
processes. In the recent years, novel applications of fluidized bed systems are
being discovered, which needs further understanding of the three phase fluidization
systems. Even though a large number of experiments have studied the various
hydrodynamic parameters of gas-liquid-solid fluidized beds, this complicated
phenomenon has not yet been fully understood.
Here the extraction efficiency can be increased by:
 Increasing extraction time or residence time.
 Decreasing particle size.
 Increasing operational temperature.
 Increasing the gas phase velocity.
 Increasing liquid phase velocity.
 Decreasing the pressure drop.
Certain parameters on which the efficiency depend are just an assumption as the
original result couldn’t be obtained due to following reasons:
 Climatic condition during operation.
 Malfunctioning of temperature controller.
 Leakage in the column due to which the volatile solvent gets
vaporized.
 Defect in the manometer.
 Pumping problems.
 Defect in designing of equipment. Etc.

25. 25
REFERENCES:
 HWAHAK KONGHAK Vol. 38, No. 2, April, 2000, pp. 225-229
(Journal of the Korean Institute of Chemical Engineers)
 Jena, H.M. (2009 b). Hydrodynamics of Gas-Liquid-Solid Fluidized and
Semi-Fluidized Beds (PhD. Thesis, National Institute of Technology,
Rourkela, India).
 Jena, H.M., Sahoo, B.K., Roy, G.K., & Meikap B.C. (2008).
Characterization of hydrodynamic properties of a gas–liquid–solid three-
phase fluidized bed with regular shape spherical glass bead particles.
Chemical Engineering Journal, 145, 50-56.
 Levenspiel, O., & Kunii, D. (1991). Fluidization Engineering (2nd ed.),
Boston: Butterworth-Heinemann. ISBN: 0-409-90233-0.
 Pandey, S.K. (2010). CFD Simulation of Hydrodynamics of Three Phase
Fluidized Bed (M.Tech. Thesis, National Institute of Technology, Rourkela,
India).
 Kim, S.P., Baker, C.G.J., & Bergougnou, M.A. (1972). Hold-Up and Axial
Mixing Characteristics of Two and Three-Phase Fluidized Beds. Canadian
Journal of Chemical Engineering, 50, 695-701.
 Bailey, S. (1996). In Y.H. Hui (Ed.), Industrial oil and fat products, (5th ed.,
vol. 4, pp. 190–212). New York: John Wiley.
 Treybal, R. E.: Mass-Transfer Operations, 3rd ed., p. 739, McGraw-
Hill(1980).
 Eggers, R., Sievers, U. and Stein, W.: J. Am. Oil Chemists Soc.,
62,1222(1985).
 Singh R.K., & Roy, G.K. (2006). Prediction of bed fluctuation ratio for gas
solid fluidization in cylindrical and non-cylindrical beds. Indian Journal of
Chemical Technology, 13, 139-143.