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Composition of feed, top and bottom and relative vol

The key components selected are n-C4 and i-C5 as light and heavy key resp

Components Xf Xd Xb K-Values

i-C4 0.1895 0.4789 0 3.4805390744

n-C4 0.03 0.505 0.00!4 .!591457

i-C5 0.314 0.0159 0.508 1.430511515

5N5 0.038 0 0.0394 0.757098147

2,2 DMC4 0.0!3 0 0.103 0.!71397855

2,3 DMC4 0.018 0 0.098 0.53159!478

2MC5 0.0!5 0 0.1079 0.505371437

3MC5 0.04 0 0.0!!1 0.457!30077

5N 0.04! 0 0.0704 0.3!5!1!515

N 0.039 0 0.0!44 0.93987917N! 0.005 0 0.004 0.153777559

"-#al$e %&"' 1.430511515 i-C5

(vg Temp T 153.15 ) !7.31 C

Cal"ulation of minimum number of sta#es Nm:

)rom )enske *+$ation

,m 10.33899

,m 11

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Cal"ulation of minimum re$u% ratio:

)rom Col$rn and nder/ood /e have an epression or minim$m re2$ rati

&'i ( Xif)*&'i - +)

0.3790004519

0.590!71!939

-0.785

-val$e can e o$nd y -0.01703993!

-0.03903315

-0.00791!7101

-0.0!47099

eed is at oiling point so +1 -0.014715!95-0.011330508

thereore at 1.7 -0.00795!!1

-0.000439

0

0

0

m61 .38!5911998 0

m 1.38!5911998 0

0

00

um 0.0!085975

-Value 1.4

e2$ ratio is 1. times the minim$m re2$ ratio

e2$ atio 1. m

e2$ atio 1.!!39094397

Cal"ulation of Number of t.eoreti"al plates:

/e rst need to nd the ratios o %mm61' and %61'

mm61 0.580993375

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61 0.!4!118!3!

)rom *rar-addo correlation Vis / Vis 0

,m, 0.3 30.51 170.

,m 11 !5.84 1!0.

, 34.375 3!7.3 191.58

40!.!9 31.!7

,$mer o theoretical plates 438.44 !.!7

444.19 8.8!

35 384.13 08.7

37.11 07.55

440.5 43.4

!53.! 90.84

:;Connell;s correlation. 58.41 71.58

)or #iscosity /e have

0.17448!!103

.1341955!7

a 0.37388550

*o !0 ?

/"tual Number of 1ras:

35

0.!

(ct$al @lates

,th

late "ien" "al"ulation &o):

olar avg #iscosity 6a m,sm

elative volatility 'a

rom :;Connell;s graph or eAciency o the col$mn %*o'

,th

*o

,th*

o

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, 58.333333333

, 59

7eed-point lo"ation:

sing "rikride empirical e+$ation

here B 140 lmolhr

915.4 lmolhr

log %,r,s' -0.085755998,r,s 0.8081577

@lates in stripping section %Belo/ the eed'

,,r6,s

,r6,s 59

,s 3.40311537

,s 33

@lates in rectiying section %(ove the eed'

,r ,-,s

,r !

)eed-point 7

Column Diameter Cal"ulation:

)looding velocity can e estimated rom the correlation given y )air

here is the 2ooding velocity ased on net area (n

(t this stage /e need to nd the li+$id-vapor 2o/ actor )D#

or top and otto

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(ss$me tray spacing o 0.5 m

8e"tifin# e"tion:

)ollo/ing are the necessary physical properties or iameter calc$lation take

10.9!

54.5

G 9.41! dynecm or 0.00941!

D/ 45!70 kghr

#/ 70180 kghr

0.0949!01!

rom graph

0.07

0.0!01

,o/ the 2ooding velocity

0.4193030581 ms

esign or 85? 2ooding at maim$m 2o/ rate

aim$m allo/ale vapor velocity ased on the net col$mn cross sctional ar

0.35!4075993 ms

aim$m vol$metric 2o/ rate !403

1.778!11

,et (rea re+$ired (n 5.0

Take do/ncomer area as 1? o the total cross sectional area

Hv "gm3

HD "gm3

)D#

"1

or val$es other than 0.0,m s$race tension a correction is applied or "1

"1

v = 0.85

v

m3hr

m3s

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Total col$mn cross sectional area (c 5.!7

iameter o the col$mn I%%(t J4'K'

ia .!8!90!7354 m or 8.8

9.0

trippin# e"tion:

)ollo/ing are the necessary physical properties or iameter calc$lation take

13.87

5!0

G 8.!1 dynecm or 0.008!1

D/ 117!00 kghr

#/ !78!0 kghr

0.77399!1

rom graph

0.0!5

0.05

,o/ the 2ooding velocity

0.3417!1918 ms

esign or 85? 2ooding at maim$m 2o/ rate

aim$m allo/ale vapor velocity ased on the net col$mn cross sctional ar

0.90497!303 ms

aim$m vol$metric 2o/ rate 4891

1.358!11

,et (rea re+$ired (n 4.7

Hv "gm3

HD "gm3

)D#

"1

or val$es other than 0.0,m s$race tension a correction is applied or "1

"1

v

= 0.85

v

m3hr

m3s

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Take do/ncomer area as 1? o the total cross sectional area

Total col$mn cross sectional area (c 5.31

iameter o the col$mn I%%(t J4'K'

ia .!01187735 m or 8.5Both diameters diLer less than 0?M thereore /e /ill have same diameter t

ThereoreM governing iameter 9

late /reas:

(c Total col$mn cross seectional area

(c 5.91

(d Cross sectional area o do/ncomer 1? o (c

(d 0.7093039

(n ,et area availale (c-(d %or single pass'

(n 5.0

(a (ctive or $ling area (c-(d

(a 4.493!15148

(h &ole area normally 10? o (a

(h 0.4493!1515

9eir Dimensions:

ecommended val$es or col$mns operating aove atmospheric press$re o

h/ 40-50mm

h/ 50 mm

Neir length o 0.77 times c is recommended or /e can $se graph or /eir l

(d(c 0.1 or 1

)rom graph the ratio

m

m

m

m

m

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l/c 0.77

l/ .11!3934 m or

Number of tra passes:

or top section

li+ 2o/ 370.!gpm

/eir length l/ 83.1!00445 inatio 4.45!4!719! gpmin o /eir

or ottom section

li+ 2o/ 94.3gpm

/eir length l/ 83.1!00445 in

atio 11.114719!8 gpmin o /eir

Both top and ottom li+$id 2o/ rate are in the given recommended range.

Fo /e have selected singe pass cross 2o/ /ith sgmental do/ncomer.

t.er tra spe"i;"ations:

(ss$med tray spacing 0.5 m

&ole diameter 5 mm

@late thickness 5 mm or caron steel

1ra

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aim$m ho/ !8.53!3 mm o li+

inim$m ho/ 54.01 mm o li+

(t minim$m rate h/6ho/ 104.0mm

)rom graph 31

minim$m design vapor velocity P 3.39397!597!

(ct$al minim$m vapor velocity inim$m #apor rate(h

.11!98855

late pressure drop:

@late press$re drop is given y

rst /e calc$late dry plate press$re drop

@late thickness&ole diameter 1

@ercent perorated area

0.1 or

rom graph 0.84

maim$m vapor velocity thro$gh holes 3.04!9317

no/ 1!.373478957

esid$al head is given y

hr .3148571 mm o li+

The total plate drop is given y hthd6hr6%h/6ho/'

ht 157.185337 mm o li+

no/ Q@ 8!3.!9573!71 or

or total press$re drop across all trays

Do=n"omer li>uid ba"?up:

"

or orice coeAcient Co/e $se graph

Co

h

hd

,m

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1otal Number of .oles:

,$mer o holes (hah

here ah area o one hole

dh 5 mm

ah

ah 1.9!375*-005

,$mer o holes 87!.44310!

877 holes

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tilities are:

tively.

8elative Volatilit

.79999!!!17

.1341955!7

1

0.58381331!

0.540717709

0.47!543!!

0.40477134

0.3!815193

0.94134!5

0.3!45751940.137097595

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o

&'i ( Xid)*&'i - +)

0.9578011419

1.4!85400578

-0.03975

0

0

0

0

00

0

0

0

0

0

0

0

0

00

.38!5911998

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m or constant "1

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n rom &EFEF

,m

ea

m

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t

t

n rom &EFEF

,m

ea

m

m

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t ro$gh o$t the col$mn.

t

Neir &eight

ngth

?

m

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83.1!004453 in

$tlet/eir .

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ms

ms

10 ?

ms

mm o li+

0.8!3!9573!7"@a

50.9580484!!1 "@a

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pM /hichever is smaller

r area

Fetisactory

ty ased on net area'

Fetisactory

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m

m

m

mmplate

m

m

t

t