VIETNAM NATIONAL UNIVERSITY HO CHI MINH CITY

HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY

FACULTY OF CHEMICAL ENGINEERING

-----------------⮘✵⮚-----------------

EXPERIMENT REPORT

PACKED COLUMN
---🙠✹🙢---

INSTRUCTORS: Dr. NGUYỄN THỊ LÊ LIÊN

SUBJECT: Laboratory of Unit Operations
CLASS: CC06 GROUP: 4B SEMESTER: 232

STUDENT INFORMATION

No. Student ID Surname First name Group Score Note

1 2153738 Lê Mỹ Khánh Quân 4B

2 2153222 Nguyễn Thái Bình 4B

3 2153763 Vương Ái Quỳnh 4B

Ho Chi Minh city, 27th February, 2024

 1. ABSTRACT
1.1. Objectives
Investigate fluid dynamics and operability of packed column by determining:
1) Effect of gas and liquid flow velocities on pressure drop when passing through the
packed column.
2) Variation of dry column Friction factor 𝑓𝑐𝑘 according to Reynolds number
standard (Re) of gas flow and deduced empirical relations.
3) The variation of the factor relates to the pressure drop of the gas flow through the
dry column and through the wet column according to the liquid flow velocity.
4) Column operability limitation diagram (flooding and weighting diagram).
1.2. Raw results:

G% ∆𝑃𝑑𝑟𝑦 ∆𝑃𝑤𝑒𝑡

L=0 L=0.2 L=0.4 L=0.6 L=0.8 L=1 L=1.2 L=1.4 L=1.6

10% 2 2 2 2 3 3 3 6 11

20% 5 6 6 6 10 11 11 23 35

30% 12 12 15 16 20 19 27 56 70

40% 17 20 23 21 35 39 55 90

50% 25 31 34 42 55 73 99

60% 37 42 49 62 95 129

70% 47 59 71 92 162

80% 61 75 103 153

90% 74 97 172

100% 93 137 233

2. EXPERIMENT THEORY
2.1. Pressure drop of inlet gas flow:
The pressure drop ∆𝑃𝑐𝑘 of the gas flow through the column depends on the mass flow
rate G of the gas flow through the dry column (no countercurrent-liquid flow). As the gas

1
flow in the spaces between the packed column increases in speed, the pressure drop also
increases. This increase is a power of 1.8 to 2.0 of the gas flow velocity.
𝑛
∆𝑃𝑐𝑘 = α𝐺 With 𝑛 = 1, 8 − 2, 0
When liquid flows in the opposite direction, the spaces between the packed column are
narrowed. The gas flow is therefore more difficult to move because some of the free
volumes between the packed column are occupied by the fluid. As the gas velocity is
increased, the blocking effect of the liquid flow increases steadily until a critical value of
the gas velocity, at which point the pressure drop of the gas flow increases dramatically.
The point corresponding to the critical value of this gas velocity is called the point of
gravity. If the gas velocity continues to increase beyond this critical value, the influence
of mutual interference between the liquid and gas flows is very large, ∆𝑃𝑐 increases
rapidly not according to equation (1) anymore. It is also difficult for the liquid to flow
down now, the column is at the flooding point.
The graph of log(∆𝑃𝑐/Z), describing the pressure drop per unit packing depth, is show in
figure 1.

Figure 1: Effect of G and L on the pressure drop of packed column (∆𝑃𝑐)

2
 2.2. Friction factor 𝑓𝑐𝑘 according to 𝑅𝑒𝑐when the column is dry

Chilton and Colburn proposed a relation between the pressure drop of the gas flow
through the dry packed column and the mass flow rate of the gas through the
column.
2
𝐺𝑍 2
∆𝑃𝑐𝑘 = 2𝑓𝑐𝑘 ρ𝑔𝐷ℎ
γℎ. γ𝑤, 𝑁/𝑚

Z: the packing depth, m.

2
G: mass flow rate of gas flow based on unit column cross- section, 𝑘𝑔/𝑠. 𝑚
𝐷ℎ: nominal size of packing material, m.
3
ρ𝑔: density of gas flow, 𝑘𝑔/𝑚

γℎ: the adjustment factor of packing material.

γ𝑤: the adjustment factor of effect of wall column on void fraction of packed column

Sherwood collected the data of previous studies and suggested the

characteristics values Raschig rings:
γℎ = 0. 35

γ𝑤 = 1

However, Zhavoronkov suggested another relation, referring the void fraction, is

more accurate for:
2
2𝑓𝑐𝑘𝐺 𝑍 2
∆𝑃𝑐𝑘 = 2 , 𝑁/𝑚
ε ρ𝐺𝐷𝑐

In which
ε: porosity of packing material
𝐷𝑒 = 4ε/a: equivalent diameter of packing material, m
2 3
a: specific surface area of packing material, 𝑚 /𝑚
Friction factor 𝑓𝑐𝑘 is a function of dimensionless 𝑅𝑒𝑐 and is determined using the
following equation:

3
 𝐺𝐷𝑐 4𝐺
𝑅𝑒𝑐 = εµ
= αµ

µ: viscosity of gas flow, kg/ms

Zhavaronkov determined the variation of gas flow from laminar flow to turbulent
flow regime through the 𝑅𝑒𝑐 of 50. In turbulent flow region, the 𝑅𝑒𝑐 is in the range
of 50 < 𝑅𝑒𝑐 < 7000 with the random packed column. The 𝑓𝑐𝑘 is calculated as

following equation:
3,8
𝑓𝑐𝑘 = 0,2
𝑅𝑒𝑐

However, this generalized relation is not accurate because it doesn’t entirely mention
the effect of packing material’s shape.
2.3. Pressure drop ∆𝑃𝑐ư for wetted column

The correlation between the pressure drop for dried column ∆𝑃𝑐𝑘 and that for wetted
column ∆𝑃𝑐ư can be described as following:

∆𝑃𝑐ư = σ∆𝑃𝑐𝑘

Therefore, we can estimate:

𝑓𝐶ư = σ∆𝑃𝑐𝑘

In which
2
σ: coefficient as a function of the liquid velocity, 𝑘𝑔/𝑚 𝑠
Leva suggested a relation showing the effect of L on σ:
Ω𝐿
σ = 10 or 𝑙𝑜𝑔σ = Ω𝐿
The value of σ depends on types, dimension, packing mode (random or
regular mode) and liquid velocity L. For example, with the Raschig rings for 12.7
mm, random packing, the porosity ε of 0.568, the liquid velocity L from 0.39 to 11.7
2
𝑘𝑔/𝑚 𝑠, the column is operated below the loading point:
Ω = 0, 084

4
 ∆ρ𝑐𝑜
From some previous studies, the relation between the ratio of ∆ρ𝑐𝑘
and coefficient
of fluid irrigation can be showed as following:

3 1,75 𝐺 𝑞
𝐴=3 𝑅𝑒𝐿
( 𝐹𝐿 ) 2
ρ𝐿 2𝑔ε

For A < 0.3 and ceramic packing material with d < 30 mm:
∆𝑝𝑐ư 1
∆𝑝𝑐𝑘
= 3
(1−𝐴)

4𝐺𝐿
𝑅𝑒𝐿 = 𝐹𝑎µ𝐿

2.4. The flooding point of packed column

When the packed column is flooded, the liquid seizes the packed section entirely,
and the flows are disordered drastically. This phenomenon is atrocious for the
operation of the packed column. The 𝐺𝐿 which is responsible for this flooding
*
situation is called 𝐺𝐿 .

Figure 2: Flooding plot of packed column

5
Zhavoronkov pointed out that the flooding situation appears when the two number
of π1 and π2 for the packed column have the relationship.

𝑓𝑐𝑘.𝑎 𝑣
2 ρ𝐺 0,2
∏ =( 3 ) 2𝑔
. ρ𝐿
. µ𝑡đ
ε
1

and

𝐿 ρ𝐺
∏ = 𝐺 ρ𝐿
2

In which
𝑓𝑐𝑘: friction factor for dried column

v: the flow rate of gas before feeding to the packed column, m/s.
µ𝑙
µ𝑡đ: relative viscosity of liquid compared to water. µ𝑡đ = µ𝑛ướ𝑐
, if the liquid is water

µ𝑡đ = 1.

Therefore, the correlation of π1 and π2 as showed in the plot of 𝑙𝑜𝑔π1 − 𝑙𝑜𝑔π2

determined the flooding graph of packed column. The limiting operation of the
packed column is under this plot.

3. EXPERIMENTAL APPARATUSES
3.1. Diagram of experimental apparatus
The experimental unit consists of:
● A glass column where the Raschig rings are packed randomly.
● Gas feeding equipment with air blower (𝐵𝑘), gas pipe, U – tube manometer
differential pressure gauge and gas flowmeter with scale from 8 to 100%.
● Water feeding equipment with feedtank (N), water pump (𝐵𝐿) and liquid
flowmeter with range from 0 to 1.6
3.2. Characteristic of packed column
Glass column:
● Diameter d = 0,09 m.

6
 ● Height H = 0,805 m.
● Packed height Z = 0,42 m.
Packing material which is Raschig rings is arranged randomly, with the nominal
2 3
diameter d=12,7 mm, surface a = 370 - 380 𝑚 /𝑚 , porosity ε = 0,586.
Diameter of steel pipe at the bottom of the column D = 0,09 m.

Figure 3: Diagram of experimental apparatus

List of components in the diagram of experimental apparatus:
● A: Panel
● C: Packed column
● E: Bottom part of column

7
 3
● 𝐹𝑘: Gas flowmeter, V = 0.286 𝑚 /𝑚𝑖𝑛
● g: a liquid level device (pipe) at the bottom part of column
● 𝐹𝐿: Liquid flowmeter, 𝐺𝐿 = 5.805 l/min
● 𝐵𝐾: air blower with a capacity of 1.0 Hp
● 𝐵𝐿: liquid pump with a capacity of 0.5 Hp
● N: liquid tank 5
● AK: pressure gauge

4. EXPERIMENTAL METHOD
4.1. Preparation:
1. Close all of the liquid valves (from 1 to 4).
2. Open valve 5 và close valve 6.
3. Turn on the air blower in 5 min for removing all moisture in the column.
Then, shut down the blower in 5-10 minutes.
4. Open valve 1 and 3. Then turn on the pump.
5. Using valve “2” to adjust the water level equal to the height of level device
3
(the height = 4
of the bottom part of the column). Then, turn off the pump
and close valve “3”.
4.2. Measurement of pressure drop for dried column:
1. Close all of the liquid valves. Open air valve “6” when the air valve “5” is
closed. Turn on the air blower and open valve “5” slowly for adjusting the
gas flow into the column
2. With a fixed gas flow rate, determining of 𝑃𝑑𝑟𝑦 on the pressure gauge for
the mmH2O unit. After that, turn off the blower and waiting for 5-10
minutes.
4.3. Measurement for pressure drop of the wetted column:
1. Switch on the air blower and adjust gas flow rate into the column in range
of 15 – 20% for maximum flow rate
2. Open the liquid valve “1” and turn on the pump. Using valve “VL” from
the liquid flowmeter to adjust the water flow rate at the top of the column.
If the float in flowmeter does not pop up as the valve “VL” is opened at
full volume, close the valve “1” closely to raise the liquid flow rate
8
 3. At a specific liquid flow rate, altering the air flow rate and measuring the
𝑃𝑤𝑒𝑡 until the operation of the column reaches the flooding point and
accomplishing the experiment. Raising the liquid flow rate and conducting
the experiment as above
Note:
3
- Adjust the valve “4” to maintain the height of water level equal to 4
the height
of the bottom part of the column through the measurement of the pressure drop.
- Using the valve “2” to reduce water level from the column, if needed.
- Turn off the water pump 𝐵𝐿 before opening the valve “4” at full volume. Finally,
switch off the air blower 𝐵𝐾.

- If the water infiltrates into the gas feeding pipe, opening the blue valve behind
the panel to eliminate water.

5. RESULTS

G G ∆P ∆P Lg
∆P/Z fdry Re Lg G Lg fdry
% kg/m2s mmH2O N/m2 ∆P/Z
10 0.087 2 19.6 32.7 5.3649 50.041 -1.0591 1.5145 0.7295
81.7
20 0.174 5 49.1 3.3530 100.08 1.9124 0.5254
5 -0.75815
196.
30 0.262 12 117.7 3.5766 150.12 2.2926 0.5534
2 -0.5820
277.
40 0.349 17 166.7 2.8501 200.16 2.4439 0.4548
9 -0.4571
408.
50 0.436 25 245.2 2.6824 250.20 2.6114 0.4285
7 -0.3602
604.
60 0.523 37 362.9 2.7569 300.24 2.7817 0.4404
9 -0.2810
768.
70 0.610 47 461.0 2.5729 350.28 2.8856 0.4104
4 -0.2140
997.
80 0.698 61 598.4 2.5567 400.33 2.9988 0.4076
3 -0.1560
90 0.785 74 725.9 1209 2.4506 450.37 -0.1049 3.0827 0.3892

9
100 0.872 93 912.3 1520 2.4947 500.41 -0.0591 3.1820 0.3970

Table 5.1. Result dry column L=0

Chart 5.1. Log ∆P/Z with respect to Log G at L=0

G G ∆P ∆P Lg
∆P/Z fwet Re Lg G Lg fwet G%
% kg/m2s mmH2O N/m2 ∆P/Z
1.000
10 0.0873 2 19.62 32.7 50.0413 -1.0592 1.5145 0.7296
0 -1.0591
1.200
20 0.1745 6 58.86 98.1 100.0827 -0.7582 1.9917 0.6046
0 -0.7581
1.000
30 0.2618 12 117.72 196.2 150.1240 -0.5821 2.2927 0.5535
0 -0.5820
1.176
40 0.3490 20 196.2 327 200.1653 -0.4571 2.5145 0.5254
5 -0.4571
1.240
50 0.4363 31 304.11 506.85 250.2067 -0.3602 2.7049 0.5220
0 -0.3602
1.135
60 0.5236 42 412.02 686.7 300.2480 -0.2810 2.8368 0.4955
1 -0.2810

10
 1.255
70 0.6108 59 578.79 964.65 350.2893 -0.2141 2.9844 0.5092
3 -0.2140
1226.2 1.229
80 0.6981 75 735.75 400.3307 -0.1561 3.0886 0.4974
5 5 -0.1560
1585.9 1.310
90 0.7853 97 951.57 450.3720 -0.1049 3.2003 0.5068
5 8 -0.1049
2239.9 1.473
100 0.8726 137 1343.97 500.4133 -0.0592 3.3502 0.5653
5 1 -0.0591

Table 5.2. Result wet column L=0.2

Chart 5.2. Log ∆P/Z with respect to Log G at L=0.2

G G ∆P ∆P Lg Lg
∆P/Z fwet Re Lg G G%
% kg/m2s mmH2O N/m2 ∆P/Z fwet
1.000
10 0.0873 2 19.62 32.7 50.0413 -1.0592 1.5145 0.7296
0 -1.0591
1.200 100.082
20 0.1745 6 58.86 98.1 -0.7582 1.9917 0.6046
0 7 -0.7581
1.250 150.124
30 0.2618 15 147.15 245.25 -0.5821 2.3896 0.6504
0 0 -0.5820
1.352 200.165
40 0.3490 23 225.63 376.05 -0.4571 2.5752 0.5861
9 3 -0.4571

11
 1.360 250.206
50 0.4363 34 333.54 555.9 -0.3602 2.7450 0.5621
0 7 -0.3602
1.324 300.248
60 0.5236 49 480.69 801.15 -0.2810 2.9037 0.5624
3 0 -0.2810
1160.8 1.510 350.289
70 0.6108 71 696.51 -0.2141 3.0648 0.5896
5 6 3 -0.2140
1684.0 1.688 400.330
80 0.6981 103 1010.43 -0.1561 3.2264 0.6352
5 5 7 -0.1560
2.324 450.372
90 0.7853 172 1687.32 2812.2 -0.1049 3.4490 0.7556
3 0 -0.1049
3809.5 2.505 500.413
100 0.8726 233 2285.73 -0.0592 3.5809 0.7959
5 4 3 -0.0591

Table 5.3. Result wet column L=0.4

Chart 5.3. Log ∆P/Z with respect to Log G at L=0.4

G G ∆P ∆P Lg Lg
∆P/Z fwet Re Lg G G%
% kg/m2s mmH2O N/m2 ∆P/Z fwet
1.000
10 0.0873 2 19.62 32.7 50.0413 -1.0592 1.5145 0.7296
0 -1.0591
1.200 100.082 -0.7581
20 0.1745 6 58.86 98.1 -0.7582 1.9917 0.6046
0 7 5

12
 1.333 150.124
30 0.2618 16 156.96 261.6 -0.5821 2.4176 0.6784
3 0 -0.5820
1.235 200.165
40 0.3490 21 206.01 343.35 -0.4571 2.5357 0.5466
3 3 -0.4571
1.680 250.206
50 0.4363 42 412.02 686.7 -0.3602 2.8368 0.6538
0 7 -0.3602
1.675 300.248
60 0.5236 62 608.22 1013.7 -0.2810 3.0059 0.6646
7 0 -0.2810
1.957 350.289
70 0.6108 92 902.52 1504.2 -0.2141 3.1773 0.7021
4 3 -0.2140
2501.5 2.508 400.330
80 0.6981 153 1500.93 -0.1561 3.3982 0.8070
5 2 7 -0.1560

Table 5.4. Result wet column L=0.6

Chart 5.4. Log ∆P/Z with respect to Log G at L=0.6

G ∆P ∆P
G% ∆P/Z fwet Re Lg G Lg ∆P/Z Lg fwet G%
kg/m2s mmH2O N/m2

10 0.0873 3 29.43 49.05 1.5000 50.0413 -1.0592 1.6906 0.9057

-1.0591
13
20 0.1745 10 98.1 163.5 2.0000 100.0827 -0.7582 2.2135 0.8265
-0.7581

30 0.2618 20 196.2 327 1.6667 150.1240 -0.5821 2.5145 0.7753

-0.5820

40 0.3490 35 343.35 572.25 2.0588 200.1653 -0.4571 2.7576 0.7685

-0.4571

50 0.4363 55 539.55 899.25 2.2000 250.2067 -0.3602 2.9539 0.7710

-0.3602

60 0.5236 95 931.95 1553.25 2.5676 300.2480 -0.2810 3.1912 0.8500

-0.2810

70 0.6108 162 1589.22 2648.7 3.4468 350.2893 -0.2141 3.4230 0.9479

-0.2140

Table 5.5. Result wet column L=0.8

Chart 5.5. Log ∆P/Z with respect to Log G at L=0.8

G ∆P ∆P Lg
G% ∆P/Z fwet Re Lg G Lg ∆P/Z G%
kg/m2s mmH2O N/m2 fwet

14
10 0.0873 3 29.43 49.05 1.5000 50.0413 -1.0592 1.6906 0.9057
-1.0591

20 0.1745 11 107.91 179.85 2.2000 100.0827 -0.7582 2.2549 0.8679

-0.7581

30 0.2618 19 186.39 310.65 1.5833 150.1240 -0.5821 2.4923 0.7530

-0.5820

40 0.3490 39 382.59 637.65 2.2941 200.1653 -0.4571 2.8046 0.8155

-0.4571

50 0.4363 73 716.13 1193.55 2.9200 250.2067 -0.3602 3.0768 0.8939

-0.3602

60 0.5236 129 1265.49 2109.15 3.4865 300.2480 -0.2810 3.3241 0.9828

-0.2810

Table 5.6. Result wet column L=1.0

Chart 5.6. Log ∆P/Z with respect to Log G at L=1.0

G ∆P ∆P
G% ∆P/Z fwet Re Lg G Lg ∆P/Z Lg fwet G%
kg/m2s mmH2O N/m2

15
10 0.0873 3 29.43 49.05 1.5000 50.0413 8.0474 1.6906 0.9057
-1.0591

20 0.1745 11 107.91 179.85 2.2000 100.0827 7.3768 2.2549 0.8679

-0.7581

30 0.2618 27 264.87 441.45 2.2500 150.1240 8.0474 2.6449 0.9057

-0.5820

40 0.3490 55 539.55 899.25 3.2353 200.1653 9.2210 2.9539 0.9648

-0.4571

50 0.4363 99 971.19 1618.65 3.9600 250.2067 10.6226 3.2092 1.0262

-0.3602

Table 5.7. Result wet column L=1.2

Chart 5.7. Log ∆P/Z with respect to Log G at L=1.2

16
 G ∆P ∆P Lg Lg
G% ∆P/Z fwet Re Lg G G%
kg/m2s mmH2O N/m2 ∆P/Z fwet

10 0.0873 6 58.86 98.1 3.0000 50.0413 16.0949 1.9917 1.2067

-1.0591

20 0.1745 23 225.63 376.05 4.6000 100.0827 15.4242 2.5752 1.1882

-0.7581

30 0.2618 56 549.36 915.6 4.6667 150.1240 16.6910 2.9617 1.2225

-0.5820

40 0.3490 90 882.9 1471.5 5.2941 200.1653 15.0889 3.1678 1.1787

-0.4571

Table 5.8. Result wet column L=1.4

Chart 5.8. Log ∆P/Z with respect to Log G at L=1.4

G ∆P ∆P Lg
G% ∆P/Z fwet Re Lg G Lg fwet G%
kg/m2s mmH2O N/m 2
∆P/Z
10 0.0873 11 107.91 179.85 5.5000 50.0413 -1.0591 -1.0592 2.2549 1.4699
20 0.1745 35 343.35 572.25 7.0000 100.0827 -0.7581 -0.7582 2.7576 1.3705

17
30 0.2618 70 686.7 1144.5 5.8333 150.1240 -0.5820 -0.5821 3.0586 1.3194

Table 5.9. Result wet column L=1.6

Chart 5.9. Log ∆P/Z with respect to Log G with L=1.6

18
Chart 5.10. The effect of gas flow rate G on ∆P/Z and the comparison
among different flow rate L from 0.2 to 1.6

19
 Chart 5.11. The effect of Re on Log f and the comparison of
different values L from L=0 to L=1.6

Chart 5.12. The relation between σ and L at specific loading points

shown in the figure

Flood
L G G
ing fdry Π2 Π1 Ln(Π2) Ln(Π1)
kg/m s % kg/m2s
2
point
0.6 5.9274 90 0.7853 2.4507 0.2581 0.0584 -1.3545 -2.8401

0.8 7.9032 80 0.7853 2.5567 0.3441 0.0482 -1.0669 -3.0333

1 9.8790 70 0.7853 2.5730 0.4301 0.0371 -0.8437 -3.2940

1.2 11.8548 60 0.7853 2.7570 0.5161 0.0292 -0.6614 -3.5333

1.4 13.8306 50 0.7853 2.6825 0.6022 0.0197 -0.5072 -3.9253

1.6 15.8064 40 0.7853 2.8501 0.6882 0.0134 -0.3737 -4.3110

1.8 17.7822 30 0.7853 3.5766 0.7742 0.0095 -0.2559 -4.6593

20
 Table 5.13. The value of flooding diagram

Chart 5.13. Flooding chart of packed column

6. DISCUSSION
6.1. Based on the raw results:
The velocity of air flowrate per unit area of column G increases, the pressure drops
increase almost linearly for both a dry column and a wet column.
As the liquid flow rate (L) increases, the column becomes more susceptible to reaching
the flooding point. Consequently, the number of results that the team can record is not
significant.
6.2 The effect of G on the pressure drop in dry and wet columns
Based on the chart and raw data:
- Dry column: As G increases, the pressure drop increases linearly.

21
 - Wet column: As G increases, the pressure drop also increases, but it is divided into
distinct areas as described in the theoretical diagram. As the liquid flowrate
increases, the column becomes more prone to reaching the flooding point.
After the loading point, the pressure drop increases suddenly and rapidly. The slope of
this region is steep, making it difficult to operate the packed column in bubble flow
regime, although it is the optimal operating regime for the column. In practice, when
conducting the experiment, we stop at the flooding points, so there is no region beyond
the loading point on the graph.
6.3 Purpose and usage of f-Re diagram:
Purpose:
● To examine the effect of the friction factor on the Re number
● To illustrate the dependence of restriction forcew in the packed column on the
fluid flowrate. As the flowrate increases, the friction factor between two phases
increases.
● Based on the chart, determine an appropriate flowrate for operating the packed
column, aiming to minimize restriction force, improve mass transfer efficiency
and prevent flooding
Usage: If one of Re or f values is given, this diagram can be used to determine the other
value by following these steps:
1. Starting from the known value on the horizontal/ vertical axis, draw a parallel line
to the vertical/ horizontal axis intersecting the f-Re diagram at one point.
2. From this point, draw a parallel line to the axis containing the unknown value and
intersect it at a specific point.
3. Read the value of the intersection point, which represents the desired value.
6.4 Does the relationship between the surveyed objectives follow the
prediction? If not, explain:
The relationship between the surveyed objectives is relatively consistent with the
prediction. Here’s an explanation:
∆𝑃
● The relationship between log 𝑙𝑜𝑔 𝑍
and log 𝑙𝑜𝑔 𝐺 follow a linear dêpndence
similar to the theoretical expectation.
● The graph showing the relationship between σ and L at some positions of G below
the loading point does not exhibit a high linear dependence.

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 ● The graph of log 𝑙𝑜𝑔 𝑓𝑐ư and 𝑅𝑒𝑐 aligns reasonably well with the theoretical
expectations.
6.5 Some factors can cause the error:
The unstable liquid/ air flowrates supplied to the packed column due to pump and fan
The presence of an unstable water column at the bottom of the column leads to water
infiltration into the pressure drop measurement tube, resulting in inaccuracies in pressure
measurements
Error in reading and experiment conduction.
The experiment conditions are different among the measurement
Note:
- After adjusting the gas flow rate and liquid flow rate, the data must be collected
immediately.
- During the experiment, allow 10 minutes for the apparatus to cool down and for the
system to stabilize before continuing the operation.
- If water accidentally enters the gas tube, open the valve after the board.

7. APPENDIX
7.1 Calculation 𝑓𝑐𝑘
2
∆𝑃𝑐𝑘. ε .ρ𝐾.𝐷𝑒
𝑓𝑐𝑘 = 2
2.𝐺 .𝑍

7.2 Calculation 𝑓𝑐ư

𝑓𝑐ư = σ. 𝑓𝑐𝑘

7.3 Calculation 𝑅𝑒𝑐𝑘

𝐺.𝐷𝑒 4𝐺
𝑅𝑒𝑐 = εμ
= αμ

0
(μ: The viscosity of air at 45 𝐶)
7.4 Calculation σ

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 ∆𝑃𝑐ư = σ. ∆𝑃𝑐𝑘

7.5 Calculation the flowrate transfer:

● Gas flowrate:
𝑘𝑔 𝐺%.ρ𝐾.0.286
𝐺( 2 ) = 60.𝐹
𝑠.𝑚

0
ρ𝐾: Density of gas stream at 45 𝐶 = 1.1305 kg/m3

● Liquid flowrate:
𝑘𝑔 𝐿.ρ𝐿.4.586
𝐿( 2 )= 60.𝐹
𝑠.𝑚

0
ρ𝐿: Density of liquid stream at 30 𝐶
𝐹: across area of the packed colum
2
π.𝑑
𝐹= 4

7.6 Calculation the flooding point

( ) 𝑓𝑐𝑘.𝑎 ρ𝐺
2
ν 0.2
Π𝐼 = 3 . 2𝑔
. ρ𝐿
. µ𝑡𝑑
ε

𝐿 ρ𝐺
Π𝐼𝐼 = 𝐺
. ρ𝐿

𝑓𝑐𝑘: friction factor of wet column

ν: long velocity of the gas stream before entering the column, m/s
𝐺
ν= 𝐹

µ𝑙
µ𝑡đ: relative viscosity of liquid compared to water µ𝑡đ = µ𝑛𝑢𝑜𝑐
. If liquid is water µ𝑡đ = 1

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 8. REFERENCES
1. Treybal, R.E., “Mass Transfer Operation”, Third Edition, pages 187 – 201,
McGraw-Hill Book Company, New York, 1980.
2. Bennett, C.O., and J.E. Myers, “Momentum, Heat and Mass Transfer”, Third Edition,
pages 187 – 201, McGraw-Hill Book Company, New York, 1982.
3. Vu Ba Minh, “Process and Units – Vol 3 – Mass Transfer”, BKU
4. McCabe W.L. et al, Units Operations of Chemical Engineering, McGraw-Hill, 1993,
pg.689.
5. Hanesian, D. and Perna A.J., “A Laboratory Manual for Fundamentals of Engineering
Design”, NJIT

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