This is about a project titled as Analysis of liq-liq flow patterns in milli channels with the help of high speed imaging techniques.

1. Analysis of Liquid-Liquid flow
patterns in Milli channels with the
help of high speed Imaging
techniques
AJAY KUMAR MAHAKUD (ECHE17-004)
AKASH KUMAR (ECHE17-005)
Under the guidance of
Dr. Koushik Guha Biswas Sir

2. About the Experiment
• Water and Toluene-acetic acid mixture are introduced in the test
passage by T mixer and the overall mass transfer coefficient for acetic
acid (10% by volume) diffusing from the organic to the aqueous phase
is estimated for the slug, annular, dispersed and inverted dispersed
flow patterns.
• Our experiment aims at investigating the influence of phase inlet
superficial velocity and conduit orientation on mass transfer
characteristics within a particular flow pattern as well as the influence
of flow pattern on the same and also about the analysis of different
types of flow Patterns in Milli channels(1 mm diameter).

3. Liquid-Liquid Flow
 Flow of a mixture of two immiscible liquids and mass transfer is
common in many industrial processes like Petroleum, Pharmaceutical
and chemical industries.
 Liquid–liquid flow in reduced dimensions - applications in extraction,
aromatic nitration etc
 When two immiscible liquids flow simultaneously in a conduit – they
form flow patterns which affects hydrodynamics and mass transfer.

4. Why millimeter size channels?
 Miniature reactors are:
1. Compact
2. Require less fluid inventory
 Marks the transition between macro and the micro domain
 Gravitational and surface forces- dominant in these dimension with progressively increasing effect
of surface forces with decrease of conduit size
 Fast mixing of the reactants, higher heat transfer compared to classical chemical reactors.

5. Experimental Procedure
 Test fluids - Water as aqueous phase
- Toluene (dyed) as organic phase
- Acetic acid as diffusing species from organic to aqueous phase
(10% by volume)
 Estimation of mass transfer co-efficient (kova)
The Physical properties of the test fluids are shown here
5
Density(Kg/m3), ρ Viscosity(Pa-s), μ Surface
Tension(N/m), σ
Water 1000 0.001 0.072
Toluene 862.27 0.00059 0.0308
Acetic Acid 1040 0.0012 0.0274
( Physical Properties of Test Fluids )

6. Mass transfer calculations
6
  A
dz
C
C
a
k
dC
Q W
W
z
W
W .
*


A
dz
Q
a
k
C
C
dC
W
z
W
W
W
.
.
.
*


( Biswas et al,chem eng.sci,2015 )

7. Solute Mass Balance at inlet & at a distance z from
the inlet
T
T
W
W
in
T
T
in
W
W C
Q
C
Q
C
Q
C
Q .
.
.
. .
. 


7
T
T
T
W
T
W
in
T
T
T
in
W
T
W
C
Q
Q
C
Q
Q
C
Q
Q
C
Q
Q


 .
.
( Biswas et al,chem eng.sci,2015 )

8. 8
Mass transfer calculations
So from
fig. 6
Now,
 
W
in
W
T
W
in
T
T
W
C
C
Q
Q
m
C
m
C
m
C 


 .
. .
.
.
*
 
A
dz
Q
a
k
C
C
C
Q
Q
m
C
m
dC
w
z
W
W
in
W
T
W
in
T
W
.
.
. .
.




Now integrating the previous Eq.(9) over the entire length of the tube
Where,
CW,out = Outlet concentration of Acetic acid at the aqueous phase (m3 of
acetic acid/ m3 of pure water)



































LA
Q
C
Q
Q
m
C
m
C
Q
Q
m
C
Q
Q
m
C
m
Q
Q
m
a
k W
in
W
T
W
in
T
out
W
T
W
in
W
T
W
in
T
T
W
ov
.
.
,
.
.
.
.
1
.
.
ln
1
1
(8)
(9)
( Biswas et al,chem eng.sci,2015 )

9. Variation of overall mass transfer coefficient
with inlet phase flowrates
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
20 40 60 80
K
ov
*a
(
per
min)
Toluene Flow Rate (µL/min)
Water Flow Rate = 20 µL/min
9

10. Different Flow Patterns in Liquid-Liquid
Flow
Dispersed Dispersed-Slug Slug Annular Slug-Annular Inverted-dispersed
flow Flow Flow Flow Flow flow

11. Outcomes of Milli Channels
• Mass transfer studies in co-current liquid–liquid flow through narrow
passages.
• Highest mass transfer co-efficient in slug flow and least in annular
flow.
• Our experiment shows that there is a significant enhancement in the
range of slug flow in the milli channels which is very desirable
because enhance the mass transfer. Mass transfer characteristics
improve with decrease in conduit size.

12. Advantage of high speed camera
• Time-Scale- As we change the rate at which the microscopic elements moves
increases drastically. A standard camera is unable to capture the rapid
movements adequately rendering the recorded data unusable.
• Visibility of Data- The results are sharp, highly contrasted images recorded on a
top of the line CMOS sensor at speeds that allow researchers to distinguish the
most relevant details one frame at a time.
• Data Analysis Made Easy- The camera software can be utilized to work with the
images created by the camera. This software allows researchers to analyze
information at record speeds by simultaneously accessing the data, processing
images, analyzing measurements, and transferring data to storage.

13. Setup and functions

14. References
 https://juniperpublishers.com/rapsci/RAPSCI.MS.ID.555679.php
 https://www.sciencedirect.com/science/article/pii/S00092509140037
41?via%3Dihub
 Ghaini, A., Mescher, A., Agar, D.W., 2011. Hydrodynamic studies of
liquid–liquid slug flows in circular microchannels, Chemical
Engineering Science, 66, 1168-1178.
 Kashid, M.N., Gerlach, I., Goetz, S., Franzke, J., Acker, J.F., Platte, F.,
Agar, D.W., Turek, S., 2005. Internal circulation within the liquid
slugs of a liquid-liquid slug-flow capillary microreactor. Ind. Eng.
Chem. Res. 2005, 44, 5003.

15. THANK YOU