Gas Scrubbing Lecture

7/31/2019 Gas Scrubbing Lecture

1/34

Rate-Base Method for Packed Columns

Absorption and stripping are frequently conducted in packed columns, particularly when

(1) the required column diameter is less than 2 ft;

(2) the pressure drop must be low, as for a vacuum service;

(3) corrosion considerations favor the use of ceramic or polymeric materials; and/or

(4) low liquid holdup is desirable.Note: Structured packing is often favored over random packing for revamps to overcome

capacity limitations of trayed towers.

Packed columns are continuous differential contacting device that do not have the

physically distinguishable stages found in trayed towers. Thus, packed columns are bestanalyzed by mass transfer considerations rather than by the equilibrium-stage concept for

trayed tray. Nevertheless, in practice, packed-tower performance is often analyzed on the

basis of equivalent equilibrium stages using a packed height equivalent to a theoretical

(equilibrium) plate (stage), called the HETP or HETS and defined by the equation

t

T

N

l

um stagesequilibriequivalent number of

ghtpacked heiHETP


2/34

outoutinin GyxLyGLx ll

assuming dilute solutions

such that Gl=Gin=Gout=GandLl=Lin=Lout=L

ininoutout GyxLyGLx ll

for the absorber

G

L

xyG

L

xy inout

for the stripper

G

Lxy

G

Lxy outin


3/34

~For the case of absorption, with mass

transfer of the solute from the gas stream to

the liquid stream, the two-film theory can

be applied as illustrated in Figure 6.30.

~A concentration gradient exists in each film.

~At the interface between the two phase,

physical equilibrium is assumed to exist.

~As with trayed tower, an operating line and

an equilibrium line are of great importance

in a packed column.

~For a given problem specification, the

location of the two lines is independent of

whether the tower is trayed or packed.

~The method for determining the minimum

absorbent liquid or stripping vapor flow

rates in a packed column is identical to the

method for trayed tower.

)()( II xxakyyakr xy

The rate of mass transfer per unitvolume of packed bed is

a represents the area for mass transfer

per unit volume of packed bed.


4/34

ak

ak

xx

yy

xxakyyakr

y

x

xy

I

I

II )()(

The composition of the interface

depends on the ratio, kxa/kya, of

the volumetric mass transfer

coefficients

The slope -kxa/kya, determines

the relative resistances of thetwo phase to mass transfer.

AE is the gas-phase

driving force (y-yI)

AF is the liquid-phase

driving force (x-xI)

mass transfer resistance

entirely in liquid phaseyy I

slight solubility;highK-value

mass transfer resistance

entirely in gas phasexx I

strong solubility;

lowK-value

turbulence

dispersion

)*(*)( xxaKyyaKr xy

y* x x* y

akK

akxxyy

akakaK xyxyy

1*111

I

I

aKkakyy

xx

akakaK yxyxx

11*111

I

I

K K-value


5/34

For a dilute system, a differential material

balance for the solute over a differentialheight of packingdl, gives:

SdlyyaKGdy y *)(

S is the cross-sectional area of the tower.

in

out

*0

y

y

Tyly

yy

dy

G

aSlKdl

G

aSKT

OGOG

y

yy

T NHyy

dy

aSK

Gl

in

out *

aSKGHy

OG in

out *y

yOG

yydyN

~HOG is the overall height of a transfer unit (HTU) based on the gas

phase. Experimental data show that the HTU varies less with G

thanKya. The smaller the HTU, the more efficient is the contacting.~NOG is the overall number of transfer units (NTU) based on the gas

phase. It represents the overall change in solute mole fraction

divided by the average mole fraction driving force. The larger the

NTU, the greater is the extent of contacting required.

in

out

in

out inout )/()/1(*

y

y

y

y KxLKGyyLKG

dy

yy

dy

AA

AKxyKxyAANOG

/)1(

)}/1()]/()][(/)1ln{[( inoutinin


6/34

AA

AHOG

/)1(

)/1ln(HETP

AAANN tOG/)1()/1ln(

A>1, NTU>Nt

A=1, NTU=Nt

A


7/34

Example 6.9

Repeat Example 6.1 for absorption in a tower packed with 1.5-in. metal Pall rings. If

HOG=2.0 ft, compute the required height.

Solution

From Example 6.1, G=180 kmol/h,L=151.5 kmol/h,yin=0.020,xin=0.0, andK=0.57.

For 97% recovery of ethyl alcohol, by material balance,

68.32000612.0

02.0

477.1)180)(57.0(

5.151

000612.0)180)(02.0)(97.0(180

)180)(02.0)(03.0(

out

in

out

y

y

KG

L

A

y

unitstransfer5.7477.1/)1477.1(

)}477.1/1()68.32](477.1/)1477.1ln{[(

/)1(

)}/1()]/()][(/)1ln{[( inoutinin

AA

AKxyKxyAA

NOG

The packing height is ft15)5.7(0.2 NHl OGOGT

NTU>Nt (=6.1)

due toA>1


8/34

Example 6.10

Experimental data have been obtained for air containing 1.6% by volume SO2 being scrubbed

with pure water in a packed column of 1.5 m

2

in cross-sectional area and 3.5 m in packedheight. Entering gas and liquid flow rates are 0.062 and 2.2 kmol/s, respectively. If the outlet

mole fraction of SO2 in the gas is 0.004 and column temperature is near ambient with KSO2=40,

calculate from the data:

(a) TheNOG for absorption of SO2

(b) TheHOG in meters(c) The volumetric overall mass transfer coefficient,Kya for SO2 in kmol/m

3-s-( y).

Solution

(a) Assume a straight equilibrium line because the system is dilute in SO2

004.0016.089.0)062.0)(40(

2.2outin yy

KGLA

unitstransfer75.389.0/)189.0(

)}89.0/1()004.0/016.0](89.0/)189.0ln{[(

/A)1(A

)}/1()]/()][(/)1ln{[( inoutinin

AKxyKxyAANOG

(b) lT=3.5m,HOG= lT/NOG=3.5/3.75=0.93 m

(c) G=0.062 kmol/s, S=1.5 m2

,Kya=G/HOGS=0.062/[(0.93)(1.5)]=0.044 kmol/m3

-s-( y)


9/34

Example 6.11

A gaseous reactor effluent consisting of 2 mol% ethylene oxide in an inert gas is scrubbed

with water at 30 C and 20 atm . The total gas feed rate is 2,500 lbmol/h, and the water rateentering the scrubber is 3,500 lbmol/h. The column, with a diameter of 4 ft, is packed in two

12-ft-high sections with 1.5-in. metal Pall rings. A liquid redistributor is located between the

two packed sections. Under the operating conditions for the scrubber, the K-value for

ethylene oxide is 0.85 and estimated values ofkya and kxa are 200 lbmol/h-ft3- y and 165

lbmol/h-ft3- x, respectively. Calculate: (a)Kya and (b)HOG

ytflbmol/h5.98)165/85.0()200/1(

1

1

111 3

ak

K

ak

aKak

K

akaK

xy

y

xyy

Solution

ft02.2)6.12)(5.98(

500,2

aSK

GH

y

OG

ft0.1)6.12)(200(

500,2

aSk

GH

y

G ft68.1)6.12)(165(

500,3

aSk

LH

x

L

22 ft6.124/)4(14.3 S

A

H

HHL

GOG 65.1)500,2)(85.0(

500,3 KG

LA

ft02.265.1

68.10.1

A

HHH L

GOG


10/34

Packed Columns Efficiency, Capacity, and Pressure Drop

Liquid holdup

Flooding

Pressure drop

Column diameterGas/liquid flow rates per

unit inside cross-sectional

area of the column

KGa orKLa

HTUPacking height

Liquid Holdup ~The lowest curve corresponds to zero liquid flow,

that is, the dry pressure drop.

~Over an almost 10-fold range of air velocity, the

pressure drop for air flowing up through thepacking is proportional to air velocity to the 1.86

power.

~As liquid flows down through the packing at an

increasing rate, gas-phase pressure drop for agiven gas velocity increases.

~Below a certain limiting gas velocity, the curve

for each liquid velocity is a straight line parallel

to the dry pressure drop curve. In this region, the

liquid holdup for each liquid velocity is constant.


11/34

~For a liquid velocity of 40 m/h, specific liquid

holdup is 0.08 m3

/m3

of packed bed until asuperficial gas velocity of 0.8 m/h is reached.

~Instead of a void fraction, , of 0.94 for the gas

to flow through, the effective void fraction is

reduced by the liquid holdup to 0.94-0.08=0.86,

causing an increased pressure drop.

~For a given liquid velocity, the upper limit to

the gas velocity for a constant liquid holdup is

termed the loading point. Below this point, the

gas phase is the continuous phase.

~Above this point, liquid begins to accumulate

or load the bed, replacing gas holdup and

causing a sharp increase in pressure drop.

~Finally, a gas velocity is reached at which theliquid surface is continuous across the top of

the packing and the column is flooded.

~At the flooding point, the pressure drop

increases infinitely with increasing gas velocity.

~The region between the loading point and

the flooding point is the loading region;

significant liquid entrainment is observed,

liquid holdup increase sharply, masstransfer efficiency decrease, and column

operation is unstable.

~Typically, the superficial gas velocity at

the loading point is approximately 70% ofthat at the flooding point.


12/34

3/23/1

Re

Fr12

a

a

N

Nh hL

L

L

Although a packed column can operate in the loading region, most packed columns are

designed to operate below the loading point, in the preloading region. The specific liquid

holdup in the preloading region depends on packing characteristics, and the viscosity,

density, and superficial velocity of the liquid according to the dimensionless expression

L

L

L

LL

a

u

a

uN

L

rceviscous fo

orceinertial fnumbernoldsliquid ReyRe L is the kinematic viscosity

g

auN L

L

2

Fr nal forcegravitatio

orceinertial fnumberFroudeliquid

The ratio of specific hydraulic area of packing, ah, to specific surface area of packing,

a, is given by

5for85.0/

5for/

Re1.0

Fr25.0

Re

Re1.0

Fr15.0

Re

LLL

LLL

NNNCaa

NNNCaa

hh

hh

~Value ofa and Ch are characteristic of the particular type and size of packing, as

listed, together with packing void fraction, , and other packing constants in Table 6.8.

~Because the specific liquid holdup is constant in the preloading region, the aboveequation does not involve gas-phase properties or gas velocity.


13/34


14/34

~At low liquid velocities, liquid

holdup can becomes so small

that the packing is no longer

completely wetted.

~When th i s occurs , pack ing

efficiency decreases dramatically,

particularly for aqueous systems

of high surface tension.

0.0012Plastic

0.0009Bright metal

0.0003Oxidized or etched metal

0.00015Ceramic

uL,min

, m/sType of Packing Material

To ensure complete wetting of packing, proven

liquid distributors and redistributors should be

used and superficial liquid velocities should

exceed the following values:


15/34

Example 6.12

An absorption column is to be designed using oil absorbent with a kinematic viscosity of

three time of water at 20 C. The superficial velocity will be 0.01m/s, which is safely abovethe minimum value for good wetting. The superficial gas velocity will be such that operation

will be in the preloading region. Two packing materials are being considered: (1) randomly

packed 50-mm metal Hiflow rings and (2) metal Montz B1-200 structured packing. Estimate

the specific liquid holdup for each of these two packings.

Solution

0.5470.979200.0Montz metal B1-200

0.8760.97792.350-mm metal Hiflow rings

Cha, m2/m3Packing

At 20 C for water, kinematic viscosity, = / =1 10-6 m2/s. Therefore, for the oil,

= / =3 10-6 m2/s.

aa

uN

L

L

L 6Re 103

01.0

8.9

)01.0( 22

Fr

a

g

auN L

L


16/34

0.0020416.67Montz metal B1-200

0.00094236.150-mm metal Hiflow ringsPacking LNRe LNFr

ingMontz Packfor506.0)00204.0()67.16)(547.0)(85.0(85.0/

Packingfor Hiflow909.0)000942.0()1.36)(876.0)(85.0(85.0/

1.025.01.0Fr

25.0Re

1.025.01.0Fr

25.0Re

NNCaa

NNCaa

LL

LL

hh

hh

3/23/1

Re

Fr12

a

a

N

Nh hL

L

L

50-mm metal Hiflow rings

333/23/1

/mm0637.0909.01.36

)000942.0(12hL

333/23/1

/mm0722.0506.067.16

)0204.0(12hL

Montz metal B1-200


17/34

Capacity and Pressure drop

~The column diameter is determined so as to safely avoid flooding and operate in thepreloading region with a pressure drop of no greater than 1.5 in. of water head per foot of

packed height (equivalent to 0.054 psi/ft of packing).

~For random packings, a nominal packing diameter not greater than one-eighth of the

diameter of the column is selected; otherwise, poor distribution of liquid and vapor flow over

the cross-sectional area of the column can occur, with liquid tending to migrate to the wall of

the column.

8/14/12.0

3

2

'

'4ln

L

G

w

L

L

GpG

G

L

g

au


18/34

Leva presented the generalized pressure drop

correlation (GPDC)

}{}{

)(2OH

2

LL

gPo uffg

FuY

L

5.0

4

Go

GT

fu

GMD

uo

is the superficial gas velocity at flooding

fis the fraction of floodingFp=packing factor(=a/

3

)


19/34

Example 6.13

Air containing 5 mol% NH3 at a total flow rate of 40 lbmol/h, enters a packed column

operating at 20 C and 1 atm, where 90% of the ammonia is scrubbed by a countercurrentflow of 3,000 lb/h of water. Use the GPDC chart of Figure 6.36 to estimate the superficial

gas flooding velocity, the column inside diameter for operation at 70% of flooding, and the

pressure drop per foot of packing for two packing materials:

(a) One-inch ceramic Rasching rings (FP=179 ft2/ft3)

(b) One-inch metal IMTP packing (FP=41 ft2

/ft3

)

Solution

Because the superficial gas velocity is highest at the bottom of the column, calculations

are made for there.Inlet gas:

MG=0.95(29)+0.05(17)=28.4 G=40 lbmol/h

G=PMG/RT=(1)(28.4)/[(0.730)(293)(1.8)]=0.0738 lb/ft3

Existing liquid:

Ammonia absorbed =0.90(0.05)(40)=1.8 lbmol/h

Water rate=166.7 lbmol/h

Mole fraction of ammonia=1.8/(166.7+1.8)=0.0107

ML=0.0107(17)+0.9893(18)=17.9 L=1.8+166.7=168.5 lbmol/hTake: L=62.4 lb/ft3 and L=1.0 cP


20/34

092.04.62

0738.0

)4.28)(40(

)9.17)(5.168(

5.05.0

L

G

G

LLG

GM

LMFX

0.1}{

14.1}{

125.0

L

L

uf

f

YFrom Figure 6.36

PPLLgP

oFg

Fg

uffFgYu

L 7.92)0.1)(14.1)(0738.0(

4.62125.0}{}{

1

)(2OH2

8.541IMTP packing

4.1179Raschig rings

uo, ft/sFP, ft2/ft3Packing

g=32.2 ft/s

11.55.95IMTP packing

16.52.87Raschig ringsDT, inuG = fuo, ft/sPacking

5.0

4

Go

GT

fu

GMD

f=0.70

FLG=0.092 and

Y=0.702(0.125)=0.088

The pressure drop is 0.88

in. of water head per footof packed height for both

packing

The IMTP packing has a much greater capacity than the Raschig rings,

since the required column cross-sectional area is reduced by about 50%.


21/34

Dp is an effective packing material diameter

~At low superficial gas velocities (modified

NRe1,000). Thus, dry pressure data shownin Figure 6.34 for Bialecki rings show an

exponential dependency on gas velocity of

about 1.86.

Theoretically based models for predicting pressure drop in packed beds with countercurrent

gas/liquid flows have been by Stichlmair et al., who use a particle model, and Billet and

Schultes, who use a channel model. Both models extend well-accepted equations for dry-bedpressure drop to account for the effect of liquid holdup.

Similar to that flow throughan empty, straight pipe.


22/34

Billet and Schultes developed a correlation for dry-gas pressure drop, Po, similar in

form to that of Figure 6.37. Their dimensionally consistent correlating equation is

wc

Goo

T

o

Kg

ua

l

P 1

2

2

3 lT=height of packing

Kw=a wall factor

T

P

w D

D

K

1

1

3

21

1

aDP

16

wall factor effective packing diameter

08.0ReRe

8.164

GGNN

CPow

G

GpoK

DuN

G )1(

Re

dry-packing resistance coefficient

Cp is a packing constant, determined

from experimental data, and tabulated

for a number of packings in Table 6.8

When the packed tower is irrigated, the liquid holdup causes the pressure drop toincrease. The experimental data are reasonably well correlated by

200exp

Re5.1

L

Nh

P

P L

o


23/34

Mass Transfer Efficiency

~The mass transfer efficiency of a packed column is incorporated in the HETP or the more

theoretically based HTUs and volumetric mass transfer coefficients.

~The HETP concept lacks a sound theoretical basis, its simplicity, coupled with the relative

ease with which equilibrium-stage calculations can be made with computed-aided

simulation programs, has made it a widely used method for estimating packed height.

~In the preloading region and where good distribution of vapor and liquid is initiated and

maintained, values of the HETP depend mainly on packing type and size, liquid viscosity,and surface tension.

Kister took the following relations for rough estimates:

1.Pall rings and similar high-efficiency random packings with low-viscosity liquids:

HETP, ft=1.5DP, in.2.Structured packing at low-to-moderate pressure with low-viscosity liquids:

HETP, ft=100/a, ft2/ft3+4/12

3.Absorption with viscous liquid:

HETP=5 to 6 ft

4.Vacuum service:HETP, ft=1.5DP, in.+0.5

5.High-pressure service (>200 psia):

HETP for structured packings may be greater than predicted by HETP, ft=100/a, ft2/ft3+4/12

6.Small-diameter columns,DT


24/34

In general, lower values of HETP are achieved with smaller-size random packings,

particularly in small-diameter columns, and with structured packings, particularly

those with large values ofa, the packing surface area per packed volume.

The experimental data of Figure 6.38 for

no.2 (2-in.-diameter) Nutter rings from

Kunesh show that in the preloading region,

the HETP is relatively independent of the

vapor-flowF-factor:

5.0)(GouF

provided that the ratio L/G is maintained

constant as the superficial gas velocity, uo,

increased. Beyond the loading point, and asthe flooding point is approached, the HETP

can increase dramatically like the pressure

drop and liquid holdup.


25/34

~Experimental mass transfer data for packed columns are usually correlated in terms of

volumetric mass transfer coefficients and/or HTUs, rather than in terms of HETPs.

~The data are obtained from experiments in which either the liquid-phase or the gas-phase

mass transfer resistance is negligible, so that the other resistance can be studied and

correlated independently.

~For applications where both resistance may be important, the two resistances are added

together according to the two-film theory of Whitman to obtain the overall resistance.

~Two film theory assumes the absence of any mass transfer resistance at the interface

between the gas and liquid phases, thus, the two phases are in equilibrium at the interface.

ak

K

akaK xyy

11*)()()( II yyaKxxakyyakr yxy

akH

akaK LgG

'11 *)()()( II PpaKccakppakr GLg cHpcHp

'*

' II

lbmol/ft3-h-atmmol/m3-s-kPakga, KGa

h-1s-1kLa, kGa, KLa

ft/hm/skL,kG

lbmol/ft3-hmol/m3-skya,kxa,Kxa, Kyalbmol/ft

3

-hmol/m3

-sr

American EngineeringSI


26/34

~Instead of using mass transfer coefficient directly for column design, the transfer unit concept

of Chilton and Colburn is often employed because HTUs:

(1)have only one dimension (length),

(2)generally vary with column conditions less than mass transfer coefficients,

(3)are related to an easily understood geometrical quantity, namely, height per theoretical stage.

ak

K

akaK xyy

11LGOG H

L

KGHH

aKkakaK yxx

111 GLOL H

KG

LHH

aSk

LM

H LL

L

L

~Figure 6.39 show the data for three different

size Berl-saddle packings for the stripping of

oxygen from water by air, in a 20-in.-I.D.

c o l u m n o p e r a t e d a t n e a r - a m b i e n t

temperature and pressure in the preloading

region.

~The effect of liquid velocity onkL

a is seen to be

quite pronounced, withkLa increasing at about

the 0.75 power of the liquid mass velocity.

~Gas velocity was to have no effect onkLa in the

preloading region.

~HL does not depend as strongly askLa on liquidvelocity.


27/34

Figure 6.40 shows the data on the effect of

liquid velocity on kLa in the preloading

region for two different size ceramic

Hiflow ring packings using the system of

CO2-air-H2O.

Figure 6.41 shows the data on the effect of

the F-factor on kLa at a constant liquid

flow rate with 50-mm plastic Pall rings

and Hiflow rings using the system of CO2-

air-H2O.

~Up to an F-factor value of about of 1.8 m-1/2-s-1-kg1/2,

which is in the preloading region, no effect gas velocity

is observed.

~Above the loading limit, kLa increases with increasing

gas velocity because of increased liquid holdup, which

increase interfacial surface area for mass transfer.

nLLL uDCak

2/11

n=0.6~0.95, 0.75 typical value

The exponent on the diffusivity isconsistent with the penetration theory.


28/34

~Figures 6.42 and 6.43 show the data for twodifferent plastic packings using the system

of NH3-air-H2O.

~The kGa vlaues are proportional to about

the 0.75 power ofF.

~The liquid velocity also affects the kGa

values, probably because as the liquid rate

is increased, the holdup increases and more

interfacial surface is created.

''67.02

nL

mGG uFDCak

DG=gas diffusivitym=0.65~0.85, 0.8 typical value

n=0.25~0.5


29/34

~The development of correlations for mass transfer from experimental data is difficult

because, as shown by Billet in a comprehensive study with metal Pall rings, values ofthe mass transfer coefficients are significantly affected by the technique used to pack

the column and the number of liquid feed distribution points per unit of column cross

section, when this number is less than 10 points/ft2.

~When 25 points/ft2

are used andDT/Dp>10, column diameter has little, if any, effect onmass transfer coefficients for packed height up to 20 ft.


30/34

Billet and Schultes assume

(1)uniform distribution of gas and liquid over the cross-sectional area of the column and

apply the two-film theory of mass transfer.(2)for the liquid-phase resistance, the liquid flows in a thin film through the irregular

channels of the packing, with continual remixing of the liquid at points of contact with

the packing such that penetration theory can applied.

)(I

LLhL ccakr 5.0

2

L

LL

t

Dk

penetration theory time of exposure of the

liquid film before remixing

au

h

u

rh

u

dht

L

L

L

HL

L

HL

L

44

h

L

LL

L

hL

LL

a

u

auD

h

ak

uH

2/14

2

h

L

LL

L

L

La

u

auD

h

CH

2/16/14

12

11

hG

oL

V

GaD

auNN

ah

CH

GG

3/1

Sc

4/3

Re

2/1

4

2/1 )()(4

)(1

G

Go

a

uN

G

Re

GG

G

DN

G

Sc

LGOG HL

KGHH

OGOGT

NHl


31/34

Example 6.14

For the absorption of ethyl alcohol form CO2 with water, as considered in Example6.1, a 2.5-ft-I.D. tower, packed with 1.5-in. metal Pall-like Rings, is to be used. It is

estimated that the tower will operate in the preloading region with a pressure drop of

approximately 1.5 in. of water head per foot of packed height. From example 6.9, the

required number of overall transfer units based on the gas phase is 7.5. EstimateHG,

HL,HOG, HETP, and the required packed height in feet using the following estimatesof flow conditions and physical properties at the bottom of the packing:

S i


32/34

Solution

Cross-sectional area of tower = (3.14)(2.5)2/4 = 4.91 ft2.

Volumetric liquid flow rate = 6,140/61.5 = 99.8 ft

3

/h.uL = superficial liquid velocity = 99.8/[(4.91)(3,600)] = 0.0056 ft/s = 0.0017 m/s

uo = superficial gas velocity = 17,480/[(0.121)(4.91)(3,600)] = 8.17 ft/s = 2.49 m/s

Packing characteristic for the 1.5-inch metal Pall-like rings

a=149.6 m2/m3 =0.952

Ch=approximately 0.7 CL=1.227 CV=0.341

Estimation of specific liquid holdup,hL:

8.17)1064.0)(6.149(

0017.0 6

Re

L

L

auN

L

522

Fr 104.48.9

)6.149()0017.0( gauN L

L

321.0525.01.0Fr

25.0Re /mm3.67)6.149(45.045.0)104.4()8.17)(7.0(85.085.0/ aNNCaa hhh

LL

323/2

3/153/2

3/1

Re

Fr/mm023.0)64.0(

8.17

)104.4(1212

a

a

N

Nh hL

L

L


33/34

Estimation ofHL:

ft62.0m19.03.67

0017.0

)0017.0)(6.149)(1082.1(

)952.0)(023.0(4

12

1

227.1

1

41211

2/1

9

6/1

2/16/1

au

auDh

CH

h

L

LL

L

L

L

Estimation ofHG:

2220)1075.0)(6.149(

49.2

5Re G

Go

a

u

N G 968.0100775.0

1075.0

4

5

Sc

GG

G

DN G

ft80.1m55.0

)3.67)(100775.0(

)6.149)(49.2()968.0()2220(

)6.149(

)952.0(4)023.0952.0(

341.0

1

)()(4

)(1

4

3/14/3

2/1

4

2/1

3/1Sc

4/3Re

2/1

4

2/1

aD

auNN

ah

CH

hG

oL

V

GGG


34/34

ft23.2)62.0(69.080.1)62.0(

7.18

6140

05.44

1748057.0

80.1 HL

KGHH LGOG

Estimation ofHOG:

Estimation of Packed Height:

ft7.16)5.7)(23.2( NHl OGOGT

Estimation of HETP:

ft67.2)69.0/1/()69.0/11(

)69.0ln(23.2

/)1(

)/1ln(HETP

AA

AHOG

69.0

7.18

6140

05.44

1748057.0

A

Gas Scrubbing Lecture

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Transcript of Gas Scrubbing Lecture