bai tap lon nhom 4_duy

8/3/2019 Bai Tap Lon Nhom 4_duy

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BI TP LN TIN NG DNG GROUP 4 - LHD K52

Li ni u

Dehydrate ha l mt qu trnh quan trng trong cng ngh x l kh xa b cng nhtrong cc nh my ch bin kh. Kh c loi b nc t ngoi khi hn ch kh

nng to nt hydrate trong vn chuyn bng ng ng v cc qu trnh lm vi kh m.

Cc vn c th xy ra:

n mn Hnh thnh nc dng lng Hnh thnh Ice Hnh thnh Hydrate kh

Bi nhng kh nng gy nguy him t hydrate kh nn chng phi c loi b. C mt

s phng php loi b s hnh thnh hydrate kh:

Loi b nc Tng nhit Gim p sut Thm cc cht c ch

Loi b nc l phng php hiu qu nht ngn nga s hnh thnh hydrate,

nhng n thc t n b hn ch bi phi c mt phn xng trung tm loi

hydrate.C 2 phng php chnh loi b nc l: hp th, hp ph...Hp ph

thng s tch c lng nc nhiu hn bi s dng cc vt liu mao qun (

Alumina, Silicagel, Zeolit...) .Tuy nhin, n b gii hn bi vt liu hp ph t hn v

i hi s ti sinh phc tp hn. V th phng php ph bin nht hin ny l hp th,

dng cc dung dch glycol hp th nc ra khi dng kh, sau dung mi hp th c

ti sinh d dng bng phng php chng ct.

Chng ta s Thit k v m phng quy trnh Dehydration bng phng php hp th s

dng dung mi hp th l TEG - Trietylenglycol bng phn mm Aspen Hysys ca

hng Aspen Technology (Cambridge, USA). Phn mm ny chuyn dng tnh ton v

thit k cc quy trnh cng ngh trong lnh vc du kh v ha du vi chnh xc

cao , thun tin v c nhiu u im.

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Li ni u ............................................................................................................................................ 1

1.1. Mc ch, vai tr ca thit k m phng ....................................................................................... 3

1.2. Tng quan qu trnh cng ngh .................................................................................................... 3

1.3. Phng php hp th ................................................................................................................... 7

Chng 2: C s ca vic thit k tnh ton m hnh ............................................................................ 10

2.1. Thp Separator .......................................................................................................................... 10

2.2. Thp hp th TEG Contactor ..................................................................................................... 12

2.3. Van VLV-100 ........................................................................................................................... 16

2.4. Tnh ton thit b trao i nhit .................................................................................................. 21

2.5. Thp ti sinh TEG Regenerator ................................................................................................. 24

2.6. Thit b trn MIX-100................................................................................................................ 26

2.7. Bm P-100 ............................................................................................................................... 272.8. Thp Remove TEG ................................................................................................................... 27

2.9. Bnh Remove H2O .................................................................................................................... 29

2.10. Cc thit b iu khin RCY-1v ADJ-1 .................................................................................. 34

Chng 3. M phng qu trnh tch nc trong kh t nhin bng dung mi hp th TEG vi phnmm Hysys ......................................................................................................................................... 36

3.1. Thit k m phng .................................................................................................................... 36

3.2. Kt qu v nhn xt ................................................................................................................... 43

Chng4. Ph lc ................................................................................................................................ 45Kt lun .............................................................................................................................................. 50

Ti liu tham kho ............................................................................................................................... 51

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Chng 1: Gii thiu tng quan

1.1. Mc ch, vai tr ca thit k m phng

*Thit k m phng l qu trnh thit k vi s tr gip ca my tnh vi cc phnmm chuyn nghip.

*M phng l 1 cng c cho php ngi k s tin hnh cng vic 1 cch hiu qu hn

khi thit k 1 qu trnh mi hoc phn tch, nghin cu cc yu t nh hng n 1 qu

trnh ang hot ng trong thc t.

*Mc ch ca thit k m phng:

- m hnh ha:

Chia nh qu trnh c tnh qu trnh

- Thit k 1 qu trnh mi

- Th li, kim tra li cc qu trnh ang tn ti

- Hiu chnh cc qu trnh ang vn hnh.

- Ti u ha cc qu trnh ang vn hnh.

*u im ca m phng

chnh xc cao Thay i b s hiu u vo Ti u ha ch cng ngh(T,P..)Nhanh chng, chnh xc, kim tra Thn thin.

1.2. Tng quan qu trnh cng nghChng ta bit nc v hydrocarbon c th hnh thnh hydrat, m c th lm tc

nghn van v ng ng. V th vic xy dng cc thp loi nc trong kh c s

dng rng ri trong cc nh my x l kh hin nay. Nc cng c th gy ra s n

mn trong kh do c cha thnh phn axit. Cho n tn ngy nay, th cc phng php

loi nc ph bin loi nc l hoc l hp th hoc l hp ph. Trong phn bi

tp trnh by di y chnh l phng php loi nc m s kt hp c 2 qu trnh

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hp th v hp ph, trong tri-ethylene glycol (TEG) v silica gel c hp th v

hp th tng ng. Mt n v phng th nghim s hp th, hp ph l nghin cu v

kh t nhin (mtan) tc dng chy v nhit hot ng vi t l loi b nc.

Cng vic th nghim bt u nhit phng bng cch kim sot cc van ca t l

lu lng kh m-tan ti 2,5 m3/gi ban u v sau cho php cc kh thng qua cc

n v hp th, hp ph. Trong khi , tri-ethylene glycol (TEG) chy 120 L / gi t

mt my bm lu thng. Th nghim c lp li vi tc dng chy kh m-tan v

nhit hot ng khc nhau trong phm vi ca 30oC n 50oC. Kt qu thc nghim

cho thy, ngy cng tng ca tc dng chy kh m-tan gy ra ngy cng tng ca

loi b nc trong khi ngy cng tng ca nhit hot ng cho mt kt qu ca

gim loi b nc. Nh vy, trong phn tch hiu qu kh, vic loi nc trong mt

n v hp th, hp ph, cc thng s nh tc dng chy kh (methane) v nhit hot ng l mt trong nhng c xem xt tin cy v li ch kinh t.

a. Mc ch

Mc ch ca m phng l kim tra phng trnh nhit ng lc hc c kh nng m

phng hn hp nc/glycol mt cch chnh xc.

b. S cng ngh

Qu trnh loi nc c th c chia thnh hai phn, loi nc trong kh v ti sinh

glycol.

Qu trnh loi nc

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Loi nc lun lun bao gm mt thp ra u vo v mt contactor(b tip xc). i kh

trc khi loi nc ta c th h thp nhit dng kh u vo th thch hp hn. do ,

do u vo c th lp t thm mt thp lm mt.

Qu trnh ti sinhCc chc nng chnh trong h thng ti sinh glycol c th c chia thnh ba loi:

1. t c c tnh p sut v nhit ti u trong ti sinh dng glycol giu

2. Tisinh Glycol

3. iu chnh li p sut v nhit dng glycol ti u c vic loi nc trong

Glycol Contactor.

Ngoi ba im chnh, c mt s tnh nng b sung c xem xt khi thit k mt

phn xng loi nc:

Ci t mt thp tch nhanh trc thp ti sinh. B phn tch ny loi b phnln cc b hydrocarbonb ha tan trong glycol.

B lc glycol giu nu c cc ht rn hoc hydrocarbon lng trong glycolTch hp cc b trao i nhit, v vy cc glycol ngho c lm lnh bng

cch nhm cc glycol phong ph, do gim thiu tiu th nng lng.Glycol hnh thnh s thay th cc glycol mt i, v d trong b cha

Bi v nhng nhn xt ny thit k ca qu trnh ti sinh khc nhau vi thit k ca nh

my. S tch hp ca b trao i nhit l c bit quan trng, bi v iu ny lm gim

tiu th nng lng tng th ca nh my.

M t quy trnh

Qu trnh ny c m t bi cc thit b c s dng trong nh my glycol.

Thp lm mt u vo

Mt b lm mt kh vo c th c s dng bi v vic loi nc s hiu qu hn

khi nhit thp. Mt li ch ca lm mt u vo l mt s nc (hydrocarbon)

trong kh s ngng t, v c loi b trong ch sn u vo, thay v trong cc tip

xc.

Mt b lm mt u vo c s dng khi nhit kh u vo l cao hn so vi

nhit mong mun trong contactor. N cng l mt cng c hu ch trong m phng nu

nhit trong contactor cn phi ti u .

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Thp ra

Thp ra s loi b loi b cc git cht lng v cht lng trong kh, c trong nc v

hydrocarbon. Loi b dng nc lng trong thp ra s gip gim bt loi b nc

trong contactor. iu ny s lm gim kch thc ca contactor(b tip xc) v lngglycol cn thit, t c iu kin yu cu vi dng kh ra khi thp.

Hydrocarbon lng cng l mt vn trong tip xc bi v chng lm tng xu hng

to glycols bt, qua lm gim hiu sut trong contactot v v tng s mt mt

glycol trong contactor v trong h thng ti sinh. Mt vn khc l cc hydrocarbon

c th c tch ly trong glycol gy nhim mi trng v qua lm gim hiu

sut loi nc.

ContactorContactor l thp hp th kh kh bng glycol. Glycol ngho vo pha trn cacontactor trong khi glycol giu c rt ra di cng ca contactor v gi n thp

ti sinh. Kh m vo cc contactor y , trong khi dng kh kh ra khi nh.

Nhit dng glycol vo contactor phi t t 3-11 C (5 n 20 F) cao hn kh

vo Contactor gim thiu s ngng t hydrocarbon vo glycol. Trong thp

contactor th nhit m di 10 C (50 F) th TEG tr nn qu nht, lm gim

hiu sut thp. Nhit contactor c th c cao ti 66 C (150 F), nhng dngglycol mt mt bay hi thng c coi l khng th chp nhn c mc cao trn

38C (100 F) B5. Cc dng chy glycol vo contactor c quyt nh bi lng

hm lng nc trong kh v s a trong thp. Mt dng chy glycol thng thng l

0,017 n 0,042 m3 nc TEG mi kg nc trong kh (2-5 gal TEG Nc / lb). Thp

contactor vi 4-6 a thng lm vic vi 0,025 m3 TEG / kg nc (3 gal / lb), trong

cc thp ln hn vi 8 hoc nhiu hn 8 a th lu lng thng gim xung cn

0,017 m3/kg (2 gal / lb)

Thp ti sinh

Thp ti sinh l mt thp chng ct, glycol v nc c tch ra. Glycol giu c

nung nng trc trong b trao i nhit trc khi dng nguyn liu i vo thp ti

sinh. nh thp s b ngng t mt phn ti sinh. Hi nc ri khi bnh ngng v

thng ra pha kh quyn. Nhit trong bnh ngng c a ra l 98,9C

(210F)Nng lng cn thit tch glycol v nc c thay th bi reboiler

trong thp ti sinh. i vi TEG nhit ti a c ngh trong reboiler l 204 C

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(400 F). Cc glycol ngho c ly t cc reboiler v chuyn ti b cha trc khi n

c ti ch hoc c sinh trc tip t reboiler.

p sut trong h thng ti sinh cao hn p sut kh quyn, iu ny l m bo

rng khng c khng kh c th xm nhp vo h thng t l thng kh quyn. Cciu kin hot ng i vi nh hng ti to tinh khit ca glycol. 204oC hiu

sut TEG ca dng glycol ngho t khong 98,6% wt [B4]. Nu tinh khit ca

glycol l khng y , n c th c ci thin bng cch s dng k thut ti to

tin tin hn.

1.3. Phng php hp th

u nhc im ca phng php hp th

u im S n gin, d tnh ton thit k, d vn hnh, qu trnh lin tc

nn c th t ng ha c, gi thnh thit b thp, t tiu hao tc

nhn lm kh kh, cc cht hp th d ch to. t hiu qu kinh t

cao v c s dng lm lnh kh n im sng -25oC -

30oC.

Nhc Khng loi c trit nc nn s rt kh khn khi ch bin kh

im nhng giai on sau, im sng cn cao do khng loi trit

hi nc ra khi kh. h im sng xung thp hn nn dngphng php hp th.

ng dng Phng php hp th c s dng rng ri lm khan kh trong

cc thit b u ni ca ng ng dn chnh v nh my ch bin

kh.

Cc cht hp th thng dngLm kh kh bng cc cht hp th da trn s chnh lch p sut hi nc trong kh v

cht hp th. Kh s c sy bng cch cho kh v dung mi tip xc ngc dng trongthp hp th, dung mi phi c i lc mnh vi nc.

Yu cu ca dung mi hp th :

C kh nng hp th hi nc trong khong rng nng , p sut v nhit C p sut hi bo ha thp mt mt trong qu trnh l t nht

Nhit si khc xa nhit si ca nc nht thp m bo tip xc tt vi hn hp kh trong thp hp th

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C chn lc cao i vi cc cu t kh c mt trong kh, ngha l c khnng hp th hi nc cao, ng thi kh nng hp th HC l thp

Tnh n mn km Khng c hi Gi thnh r

Mt s cht hp th thng dng:

Cc i lng ha l EG DEG TEG PG

Khi lng phn t 62,7 106,12 150,18 76,09

T trng tng i 2020 1,116 1,118 1,125 1,034

Nhit si (1atm) oC 197,3 244,8 278,3 188,2

Nhit nng chy,o

C -13 -8 -7,2 -60Nhit bt u phn - 164 206 -

hy,oC

Nhit ti sinh, oC 165 164 206 -

nht 20oC, cP 20,9 35,7 47,8 56,0

Nhit dung ring, 2,35 2,09 2,20 2,47

kj/kg.C

u nhc im ca cc cht hp th:u im Nhc im

DEG (Dietylenglycol)

ht m cao, kh bn khi c mt cc Tiu hao do tht thot cao hn so vi

cht: S,O2, CO2 nhit thng TEG. Khi ti sinh kh thu c dung dch

c nng DEG ln hn 95%. im

sng thp hn so vi khi s dng TEG

MEA (Monotanolamin) 10-30%, DEG 60-80%, H 2O 5 - 10%Cht hp th c th tch nc H 2S, CO2 tht thot ln hn so vi khi s dng

ra khi kh, tc l ng thi sy kh v TEG. Ch s dng sy v lm sch kh

lm sch kh. Kh nng to mng thp Acid. D gy n mn kim loi nhit

ti sinh, im sng ca kh thp

TEG (Trietylenglycol)

ht m cao, to im sng cho kh i hi chi ph u t cao. Dung dch

sy cao (27,8 - 47,3) , bn cao khi c TEG c kh nng to mng khi c mt

mt hp cht lu hunh, oxy v CO 2 cc cht lng HC nh. ha tan ca cc

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nhit bnh thng. Khi ti sinh, d HC trong TEG cao hn so vi DEG.

dng thu c dung dch c nng

cao, trn 99%

La chn cht hp th

Vi thnh phn kh vo nh sau:

Cu t Phn mol

N2 0.0010

H2S 0.0010

CO2 0.0020

C1 0.8989

C2 0.0310

C3 0.0148

i-C4 0.0059

n-C4 0.0030

i-C5 0.0010

n-C5 0.0005

H2O 0.0409

Nh vy thnh phn kh c cha kh Acid (H2S v CO2) nh vy s khng s dng DEG

v n c th b phn hy bi cc tc nhn ny nhit thc hin ti sinh (khong

206

o

C). Mt khc nng kh Acid khng qu cao nn ta c th ch cn s dng TEG.Ngoi ra n c s tht thot trong qu trnh hp th v ti sinh kh nh. Nh vy ta chn

TEG lm cht hp th.

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Chng 2: C s ca vic thit k tnh ton m hnh

2.1. Thp Separator

Thp Separator dng tch nc t do i cng vi kh ra khi hi hp trc khi i vothp hp th.

Dng vo:

Tn dng Inlet Gas

Nhit [C] 30

p sut [kPa] 6200

Lu lng mole 500

[kgmole/h]Thnh phn

Cu t Phn mole

N2 0.0010

H2S 0.0010

CO2 0.0020

C1 0.8989

C2 0.0310C3 0.0148

i-C4 0.0059

n-C4 0.0030

i-C5 0.0010

n-C5 0.0005

H2O 0.0409

TEG 0.0000

y l mt thp tch vt l n thun dng cc tm chn c tc dng gi li nc t doi theo dng kh. Vi ng knh trung bnh khong 0,05 m.

Vi tn hao p sut:

Dng Inlet : 100 kPa Dng Vapour Outlet : 100 kPa

p sut cc dng :

PCondensate = PInlet - PInlet = 6200 - 100 = 6100 kPa

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PGas to Contactor= PInlet - (PVapour Outlet + PInlet) = 6200 - 200 = 6000 kPa

Nh vy qua thit b ny nhit ca dng kh gim xung v nhit hydrate ca

dng kh nh hn ti v mt lng kh ln H2O cng H2S c tch ra dng lng v ra

y ca thp.

Dng ra:

y

Tn dng Condensat

Nhit (oC) 29.60

p sut (kPa) 6100

Lu lng mole 20.04(kgmole/h)

Thnh phn Phn mole

H2S 0.0001

H2O 0.9999

nh:

Tn dng Gas to Contactor

Nhit (oC) 29.16

p sut (kPa) 6000

Lu lng mole 480,0

(kgmole/h)

Thnh phn Phn mole

Nitrogen 0.0010

H2S 0.0010CO2 0.0021

Methane 0.9364

Ethane 0.0323

Propane 0.0154

i-Butane 0.0061

n-Butane 0.0031

i-Pentane 0.0010

n-Pentane 0.0005

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CO2 0.0000

C1 0.0000

C2 0.0000

C3 0.0000

i C4 0.0000

n C4 0.0000

i C5 0.0000

nC5 0.0000

H2O 0.4901

TEG 0.5099

Vy ta c lu lng ring ca dung mi l m = = 6.127 kg/kg H2O.

p sut nh thp l 6190 kpa, y l 6200 kpa. Thp gm c 8 a l thuyt Bi

ton cn tnh nhng thng s sau:

Nhit , lu lng, p sut, thnh phn dng TEG giuNhit , lu lng, p sut, thnh phn kh kh

Nng cc cu t trong dng kh kh c tnh theo cng thc sau:

Yi = (

Trong :

B = A1A2Ai-1 + A2A3Ai-1 + Ai

C = A1A2Ai-1

D = A1A2Ai

)

Xo : nng cu t cn hp th trong dung mi

Vi Ai, l yu t hp th ca cu t trn mm i, do thp hp th ta nhit nh coi nh ng

nhit nn A1 = A2 = An

Ai = Aj =

Vi

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Kj - hng s cn bng pha ca cu t cn hp th nhit trung bnh ca

qu trnh hp th

L - lu lng dung mi i vo thp hp th (mol/h) G -

lu lng kh nguyn liu (mol/h)

Aj - yu t hp th ca cu t j

Thng th ta gi s lng mole hi v lng ra khi a bng nhau. Khi A c tnh

nh sau:

Aj

Thnh phn cc cu t trong dung mi bo ha ra khi thp c tnh nh sau:

Xj = Yj

Phn mole ca H2O c tnh bng cch ly 1 tr phn mole cc cu t cn li.

Theo nhng cng thc nh trn ta tnh ton c bng s liu sau:

Cu t H s K Yj Xj

N2 6.415 0.0007 0.0001H2S 9.203 0.0014 0.0010

CO2 8.524 0.0020 0.0005

C1 19.52 0.9360 0.0106

C2 19.43 0.0329 0.0008

C3 14.70 0.0156 0.0005

iC4 13.81 0.0060 0.0001

n C4 13.50 0.0032 0.0001

i C5 13.05 0.0010 0.0001

n C5 13.04 0.0007 0.0001

H2O 0.0003 0.4985

TEG 8.816 0.0000 0.4877

Nhit ca cc sn phm c ly sp x bng vi nhit ca kh nguyn liu l

30oC.

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p sut ca kh ly bng p sut trn nh thp l 6190 Kpa, ca TEG bo ly bng p sut

ca y l 6200 Kpa.

Lu lng cc dng sn phm c tnh nh sau:

Bit thnh phn nguyn liu vo ta bit c d = 2,848 kgmole/dm 3, ta c :

V = = 168,54.10-3 m3/h.

Bit thnh phn dung mi bo ta xc nh c d = 13.55 kgmole/m3. Tnh

lu lng ca dung mi bo ra khi y thp bng cng thc :

L = V( w1 - w2 )( m + 1 )

Trong : w1 = 0.45.10-3 kg/m3 - hm m ca kh nguyn liu

w2 = 0.03.10-3 kg/m3 - hm m ca kh kh ra nh thp Vy

tnh ra c :

L = 168.54. 103 ( 0.45. 10-3 - 0.03. 10-3 )( 6.127 + 1 ) = 560,01 kg/h ( hay 6,79

kgmole/h )

Trong thp ta c :

Vnl + Lnl = Vsp + Lsp

Vy lu lng dng kh kh l :

Vnl = 480 + 6.519 - 6.79 = 479.729 kgmole/h

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2.3. Van VLV-100

Dng vt cht i qua van, bm, v cc thit b trao i nhit xem nh c thnh phn v

lu lng khng i.

Do , ta c:

( ) ( ) ( )

Bit p sut dng u vo, chnh lch p sut P, tnh c p sut dng u ra:

( )

Tnh nhit u ra dng LP TEG.

p dng phng trnh Peng-Robinson:

Trong :

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BI TP LN TIN NG DNG

* (

Trong :

P: Pressure

Vm: Molar Volume

T: Temperature

Tc : Critical temperature

Pc : Critical pressure

a : Peng-Robinson

constant a b : Peng-

Robinson constant b

: Acentric fractor

R : Molar gas constant

GROUP 4 - LHD K52

) ( )+

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Tra cc thng s ca dng TEG, ta c bng s liu sau:

Cu t Phn mol xi Acentric fractor Tc (K) Pc (kPa)N2 8,99E-05 0,0372 126 3400

H2S 1,02E-03 0,0948 373 8960CO2 4,87E-04 0,2667 304 7380

Metan 1,07E-02 0,0104 191 4600

Etan 8,67E-04 0,0979 305 4880

Propan 5,55E-04 0,1522 370 4250

i-Butan 8,08E-05 0,1852 408 3650

n-Butan 4,69E-05 0,1995 425 3800

i-Pentan 9,71E-06 0,228 460 3390

n-Pentan 5,26E-06 0,2514 470 3370

H2O 0,49865285 0,3443 647 22060

TEG 0,48746342 0,563 806 3958

Acentric fractor ca hn hp:

Nhit ti hn ca hn hp:

( )

p sut ti hn ca hn hp:

( )

Tnh cc thng s ca phng trnh:

* ( )( )+

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* ( )+

* ( )+

Th tch mol ca hn hp Vm lun thay i ty theo nhit v p sut. Ta cho cnh p sut, th mt vi gi tr ca T tm mi quan h V m = f(T).

P = 180kPa.

T (K) Vm.100 (l/mol)

250 3,82665

270 3,85929

280 3,87667

290 3,8948300 3,91373

310 3,9335

320 3,95417

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BI TP LN TIN NG DNG

Vm.100 3,94(l/mol)Molar

Volume 3,92

3,9

3,88

3,86

3,84

3,82

3,8

150 200

GROUP 4 - LHD K52

y = 0,0018x + 3,3798

250 300 350

Temperature (K)

Ta c phng trnh lin h Vm v T nh sau:

Vm.100 = 0,0018T +3,3798

Thay Vm vo phng trnh Peng-Robinson

* ( )+

( ) ( )

Ta c T=310,56K (hay 37,4oC).

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BI TP LN TIN NG DNG

2.4. Tnh ton thit b trao i

nhit Thit b trao i nhit TEG

- Ex

Dng th nht: Pump out >

Nhit (oC ) 51.42

Thnh phn % Phn mol

GROUP 4 - LHD K52

TEG to Recycle

35

Nhit dung ring (j/kg.)

H2O 0.490126 971

TEGlycol 0.509874 1032

Ta c nhit dung ring trung binh (C ): C1 =0.490126 971 +0.5098741032= 1002

(j/kg.)

Lu lng khi lng : G1 = 556.7 ( kg/h)

Vt1 =51.42 -35 = 16.42 (OC )

Dng th hai: Dry Gas Sala Gas:

*Nhit (OC ) 30.63 t 2c (nhit cn tm bng tay so snh)

Lu lng khi lng G 2 = 8392 (kg/h)

Thnh phn % s mol (% ni ) Nhit dung ring (J/kg.)(

Ci )

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Nito 0.001041 6783

H 2 S0.001025 1812

CO 2 0.002076 847

CH 4 0.936858 932

C2 H6 0.032302 1005

C 3 H 8

i-C4

n-C4

i-C5

n-C5

0.012420

0.006149

0.003127

0.001042

0.00521

854

814

913

1038

1235H2 O 0.000439 971

TEG 000 000

Ta tnh c nhit dung ring trung bnh ca dng 2 nh sau:

8

C C n

2 = i i =0.001416783+0.0010251012.=1214 (J/kg )i = 1

p dng cng thc: Q = G C (t - t ) = G C ( t* - t ) (CT 2-21 Ha cng 1)1 1 1d 2 c 2 2 2c 2d

Thay s vo ta c : 556.7100216.42 =1214 8392 ( t* 2c - 30.63 )

*

t2c = 31.56 (oC ) 31.53 (oC ) (gi tri tnh ton theo Hysis) chlch do lm trn.

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Thit b trao i nhit L/R HEX

Dng th nht : Regen Bttms Lean from L/R

Nhit (OC ) 131.7 52.90

Lu lng (kg/h) 556.7 556.7

Thnh phn % mol

TEGlycol 0.509851

H2O 0.490149

Dng th hai : LPTEG Regen Feed

**

Nhit (OC ) t 2c 110

Lu lng: 562.4 (Kg/h)

Thnh phn % s mol (% ni ) Nhit dung ring (J/kg.)(Ci )

Nito 0.000090 6783

H 2 S0.001021 1812

CO 2 0.000487 847

CH 4 0.010721 932

C2 H6 0.000867 1005

C 3 H 80.000555 854

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i-C4 0.000081 814

n-C4 0.000047 913

i-C5 0.000010 1038

n-C5 0.000015 1235

H2 O

TEG0.498653

0.487463

971

000

Tnh ton tng t nh thit b trao i nhit th nht:p dng cng thc (2-22 SGK

HC1)

Ta tnh c t **2c = 35.32 (OC )

2.5. Thp ti sinh TEG RegeneratorThit b ti sinh l mt thp chng ct, TEG v nc c tch ra. p sut trong h

thng ti sinh cao hn p sut kh quyn iu ny m bo rng khng c khng kh c

th xm nhp vo h thng t l thng kh quyn. Cc iu kin hot ng c nh hng

ti ti to tinh khit ca Glycol.

Nh ta t iu kin th p sut hot ng ca thp ti sinh cao hn p sut khquyn mt cht trong khong 110 kPa - 150 kPa.

Trong khi nhit nh khng thp hn 100 oC, m bo nc dng hi s c

tch ra nh thp v nhit khng c vt qu 206 oC ti v qu nhit ny th

TEG b phn hy, nh vy s gy mt mt lng TEG ln hn.

Cn bng vt liu :

Dng kh (ch yu l nc dng hi) ra nh ca thp ti sinh:

Dng TEG ra khi y ca thp ti sinh:

w kgmole/h

Tnh ton Rmin

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T s liu s tay ha cng tp 2 ta c gin lng hi ca hn hp cu t. T gin ta

xc nh c m, vy ta c:

= m = 0.075

Vy: R min = 0.5714

M theo gi thit m phng trong HYSYS ta chn gi tr R = 0,6

= 1,28

1,28 l gi tr chp nhn c

Cn bng nhit:Ta c bng nhit dung ring ca cc cu t nh sau :

Cu t Cp(cal/molK)

CH4 8,54

C2H6 12,58

C3H8 17,57

n-C4H10 23,29i-C4H10 23,14

n-C5H12 28,73

i-C5H12 28,39

N2 6,96

H2S 8,17

CO2 8,87

Da vo bng trn tnh c nhit dung ring ca cc dng Regen feed, Sour Gas,Regen Bttms nh sau :

Dng C

Regen Feed 240,1

Sour Gas 37,57

Regen Bttms 259,7

P (KJ/Kmole.oC)

CP

C pi C i25


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p dng cc cng thc tnh nhit lng

QcondQ = C.L.( t2 - t1 ) ta c bng gi tr sau : Q =

C.L.t

QrebQ = 2.107 - 1,5.C.L.t

Trong :

C - nhit dung ca dng tng ng

t - nhit ca dng

L - lu lng ca dn

Dng Nhit lng ( KJ/h )

CondQ 5,681.104

Reboiler 2,000.107

Regen feed 3,510.106

Sour Gas 5,681.104

Regen Bttms 2,245.104

RebQ 5,819.104

Nhit lng ca ton thp c tnh nh sau:

Q = QRegen Feed + QrebQ - QcondQ - QRegen Bttms - QSour Gas

= 3,43.106 ( KJ/h )

2.6. Thit b trn MIX-100Trong qu trnh lm vic s c mt lng nh TEG b mt mt, v th yu cu to mt

sng chc chn rng dng nguyn liu cn bng c duy tr.

y s tnh ton lng dng TEG:

(Lng TEG)TEG to Pump = (Lng TEG)Makeup TEG + (Lng TEG)Lean From L/R

FTEG to Pump . C%TEG to Pump = FMakeup TEG . C%Makeup TEG + FLean From L/R . C%Lean to L/R

(FC%) (FC%)F Pump

Trong :

Makeup Lean

C % Pump

FPump , FMakeup , FLean: Lu lng mol ca dng TEG to Pump, Makeup TEG,

Lean toR/L

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C%Pump ,C%Makeup, C%Lean : Nng phn mol ca TEG trong dng TEG to

Pump, Makeup TEG, Lean to R/L

p dng: FPump = 6,519 kgmole/h

Tng t vi p sut v nhit : TPump = 52,9 oC v PPump =80 kPa.

2.7. Bm P-100

Qu trnh tnh ton lu lng, p sut, nhit u ra tng t nh vi van VLV-100

2.8. Thp Remove TEG

Mt tiu chun xc nh hiu qu ca qu trnh tch nc l im sng kh kh. Vn ny c th c kim tra bng vic tm nhit ca kh m ti nc bt u

ngng t. Trc ht tt c TEG phi c loi b bi TEG c nh hng ti im sng

ca nc. Vn ny c thc hin bi vic s dng thit b Component Splitter.

Dng hi ra ngoi c lm lnh v nhit ra ca n c iu khin bi thit b

Adjust tm im sng ca dng kh.

Nhim v ca thp Remove l tch loi trit TEG trong hn hp sn phm nh ca thp

TEG Contactor.TEG sau khi c tch s ra khi nh thp dng lng cn sn phm ychnh l hn hp kh.

Stream Feed:

Name Sale Gas

Nhit oC 31,54

p sut kPa 6155

Lu lng mol (kmol/h) 479,7

Lu lng khi lng (kg/h) 83,92

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Vapour 1,0

Thnh phn

Cu t Phn mol

N2 0.001041

H2S 0.001025

C02 0.002076

C1 0.936858

C2 0.032302

C3 0.015420

iC4 0.006149

nC4 0.003127

iC5 0.001042

nC5 0.000521

H20 0.000439

TEG 0.000000

Total 1

Do thnh phn ban u ca nguyn liu ca thp lng TEG rt khng ng k phn mol

= 0 do phn mol ca sn phm y cng s khng thay i.Lu lng mol,lu lngkhi lng ca dng sn phm y cng s khng thay i.

Sn phm y s ging nh dng nguyn liu vo:

Cu t Phn mol

N2 0.001041

H2S 0.001025

C02 0.002076C1 0.936858

C2 0.032302

C3 0.015420

iC4 0.006149

nC4 0.003127

iC5 0.001042

nC5 0.000521

H20 0.000439

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TEG 0.000000

Total 1

V sn phm nh s duy nht c TEG.vi phn mol=1 v cc cu t khc =0.

Thp thc hin iu kin ng p P=6155 kPa bng vi p sut ca dng nguyn liu

vo cng nh 2 dng sn phm.

TTEG=100C v TWaterdew-point= -32.53 oC.

2.9. Bnh Remove H2OThit b ny s loi b nc ngng ra khi dng kh.

2 41 L

A L'

3D'

D

5

1 - Thit b phn phi u vo

2 - B tch sng m

3 - u vo

4 - u ra ca dng kh

5 - u ra ca dng lng

Cc d kin bit:

Dng kh vo: Water Dewpoint

Thnh phn pha: lng-kh

Nhit : -32,53oC

p sut: 6155 KPa

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Lu lng: 26,67 m3/h

Thnh phn v mole ca cc cu t:

STT Cu t % mole (Ci)

1 Nito 1,041.10-3

2 H2S 1,025.10-3

3 CO2 2,076.10-3

4 CH4 936,858.10-3

5 C2H6 32,302.10-3

6 C3H8 15,4240.10-3

7 i-C4H10 6,149.10-3

8 n-C4H10 3,127.10-3

9 i-C5H12 1,042.10-3

10 n-C5H12 0,512.10-3

11 H2O 0,439.10-3

12 TEG 0

Tnh ton:

T bng s liu v thnh phn phn mole cc cu t trn ta tnh c:

- Khi lng phn t trung bnh dng Water Dewpoint:

Ta c:

Trong Z l h s nn ca kh ta chn Z =1 Do

khi lng ring ca dng vo:

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- Tng t ta tnh c khi lng ring ca dng kh vo l k = 79,48 Kg/m3

- Lu lng ca dng vo (Water Dewpoint) Qw = 8392 (Kg/h) hay 479,7

(Kmole/h)

- Lu lng ca lng vo bnh l: 0.0038 m3/h

- Lu lng ca kh vo bnh l: 26,6662 m3/h

T s ha tan ca CO2 trong nc l 1,45Kg/1000KgH2O ( y ta coi lng CO2 ha

tan trong nc l bng khng do lng nc nh)

Do t s ca pha lng trn pha hi l nh cho nn ta chon kiu bnh tch nm

ngang nh hnh trn. Ta la chon thi gian lu trong thit b l 2 pht ( cc bong kh

c th thot ra khi nc ) v t s L/D= 3.

Khi ta c:

- Khng gian dnh cho khi lng l:

- Khng gian dnh cho pha kh l:

Tc cc i ca dng kh cho php tch cc git lng trong mt bnh tch nm

ngang l:

( )

Trong K l h s xc nh biu 4.36 (trang 136- Gio trnh cng ngh lc du

- Phan T Bng - Nh xut bn xy dng - H ni 2002)

Lu lng kh Qv c tnh:

( ) ( ) ( ) ( )

Trong : Pb: p sut tiu chun 1atm

Tb: nhit tiu chun 289K

Qv m3/ngy

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T y ta c S = 0.1956 m2

S y l din tch ca dng kh m2

dm bo s hot ng tt ca bnh tch thng cn them mt khng gian dm gia

vng dnh cho lng v vng anh cho kh. Vng m c th cha n khong 25%

vng dnh cho kh. V vy ta chn din tch S* = S + 25%S l din tch vng kh. Ta

c s d sau:

Gi S1 l din tch vng lng th S1= Vl/L

L l chiu di ca thit b (tm chp nhn L/D = L/D =3)

s*

h

snc

R l bn knh hinh trn. (D=2R)

Vi cc php tnh hnh hc thng thng ta tinh c: Bn

knh ca bnh R = 0.28 m

ng knh ca bnh D = 0.56 m

Chiu di ca bnh L = 1.68 m

Tit din bnh tch 0.246 m2

Tit din vng kh 0.1956 m2

Tit din vng lng 1,5.10-3 m2

Tit din vng m l 0.0489 m2

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+ La chn li vo v li ra:

Li vo v li ra phi tun th cc cng thc sau:

Trong : u, uk , unc l tc di ca dng vo kh v nc ra

v k l khi lng ring ca dng vo v kh ra.Mt khc: u = Q/Si

Si l din tch ca li vo (ng dn vo) o ta c th chn cc kch thc li vo v ranh sau:

ng knh ng li vo: 4 cm

ng knh ng li ra ca kh: 3,5 cm

ng knh li ra ca lng: 1 cm

Ch :

- Trong qu trnh tch nhit v p sut khng thay i

- Lu lng dng lng v kh vo xp x bng vi vi lu lng dng lng kh ra. V l

bnh tch lng kh (tch nc ra khi hn hp kh) trong qu trnh ny cn bng vt cht v

vt liu l khng i. Coi nh tch hon ton (tch hon ton nc ra v coi lng CO 2 ha

tan khng ng k) hn hp ny thnh 2 pha do thnh phn phn mole ca tung cu t

trong tng dng (pha) thay i nhng hm lng khng thay i v ta c th tnh ton

c d dang cc dng ra nh sau:

+ Dng lng: ch c nc v 1 phn nh CO2:

STT XS H2O (pha lng)

Nhit -32,53 oC

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p sut 6115 KPa

Lu lng 0.0038 m3/h

Thnh phn Ch yu l nc.

+ Dng kh:

STT GAS OUT (pha kh)

Nhit -32,53oC

p sut 6155 KPa

Lu lng 26,6662 m3/h

Thnh phn (phn mole) N2 1,042.10-3

H2S 1,026.10-3

CO2 2,077.10-3

CH4 937,260.10-3

C2H6 32,316.10-3

C3H8 15,426.10-3

i-C4H10 6,152.10-3

n-C4H10 3,128.10-3

i-C5H12 1,043.10

-3

n-C5H12 0,521.10-3

2.10. Cc thit b iu khin RCY-1vADJ-1 Thit b iu khin RCY-1

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Thit b RCY-1 c thit lp dng Block vi cc dng qu trnh. Nguyn liu vo trong

khi c tnh ton dng tun hon, v a ra cc s liu gi nh cho dng tun hon.Cc

bc Hysys tnh ton nh sau:

Hysys s dng cc iu khin ca dng v gii quyt vi s dng phhp vi dng tnh ton

Hysys s so snh cc gi tr ca dng c tnh ton vi cc gi tr tngng ca dng gi nh

Trn c s s khc nhau gia cc gi tr, Hysys s bin i cc gi tr dnggi nh

Qu trnh tnh ton s lp li cho ti khi cc gi tr c tnh ton gp cc gitr tng ng ca dng gi nh vi sai s nh hn sai s cho php c

thit lp

Trong trng hp ny, dng lean TEG (TEG Feed) l c lng gc s c thay th vi

dng lean TEG mi c tnh ton (TEG to Recycle) v hai thp TEG Contactor v TEG

Regenerator s chy cho ti khi vng tun hon hi t.

Thit b iu khin ADJ-1

y, thit b iu khin ADJ-1 s bin i nhit ca im ngng t nc ti cc gi

tr im sng c thit lp ph hp vi dng Gas Out.

Thm thit b iu khin iu khin nhit im sng ca dng ti khi dng XS

H2O ln hn 0 v ln hn gi tr lm vic ca dng c thit khng qu 0.01 kg/h.

Nh vy chng trnh s lp li ti khi nhit im sng trong kh t yu cu thit

lp l - 32,53 oC.

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Chng 3. M phng qu trnh tch nc trong kh t nhin bng dungmi hp

th TEG vi phn mm Hysys

3.1. Thit k m phngOver View Processing:

Thit lp cu t, gi cht lu:

CompositionComponents N2

H2SCO2C1

C2C3i-C4n-C4i-C5n-C5H2OTEG

Fluid Pkgs Peng - Robinson

Nhp dng Inlet Gas:

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Worksheet/ConditionsName Inlet GasTemperature [C] 30Pressure [kPa] 6200

Molar Flow [kgmole/h] 500Worksheet/CompositionComponent Mole Fractions

N2 0.0010H2S 0.0010CO2 0.0020C1 0.8989C2 0.0310C3 0.0148i-C4 0.0059

n-C4 0.0030i-C5 0.0010n-C5 0.0005H2O 0.0409TEG 0.0000

Nhp thit b tch Separator:

Design/Connections

Name Separator Inlets Inlet GasVapour Outlet Gas to Contactor Liquid Outlet CondensatDesign/Parameters/Delta PInlet 100 kPaVapour Oulet 100 kPa

Nhp dng TEG Feed:

Worksheet/ConditionsName TEG FeedTemperature [C] 35Pressure [kPa] 6200Vol Flow [m3/h] 0.5Worksheet/CompositionComponent Mole FractionsH2O 0.49TEG 0.51

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Thit b hp th TEG Contactor:

Design/ConnectionsName TEG Contactor Num of Stages 8Top Stage Inlet TEG FeedBottom Stage Inlet Gas to Contactor Ovhd Vapour Outlet Dry GasBottoms Liquid Outlet Rich TEGParametersPressure Stage Top [kPa] 6190Pressure Stage Bottoms [kPa] 6200Parameters/SolverDamping Fixed

Nhp Van VLV-100:

Design/ConnectionsName VLV-100Inlet Rich TEGOutlet LP TEG

Nhp thit b trao i nhit L/R HEX:

Design/ConnectionsName L/R HEXTube Side Inlet Regen BttmsTube side Outlet Learn from L/R Shell Side Inlet LP TEGShell Side Outlet Regen FeedDesign/ParametersHeat Exchanger Model Exchanger Design (Weighted)

Tube Side - Delta P 70 kPaShell Side - Delta P 70 kPaWorksheet/Conditions/Regen FeedTemperature [C] 110Pressure [kPa] 110

Nhp thp ti sinh TEG Regenerator:

Design/ConnectionsColumn Name TEG Regenerator

Num of Stages 8

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Inlet Streams - Inlet Stage Regen Feed, Stage 2Cond Energy Stream Cond QReboiler Energy Stream Reb QCondenser Full Reflux

Ovhd Vapour Oulet Sour GasBttms Liquid Outlet Regen BttmsDesign/Specs/Column Specifications

Name Reflux RatioSpec Value 1.5Active Check Design/Specs/Draw Spec

Name Ovhd Vap RateDraw Sour GasSpec Value 0.4870 kgmole/h

Active Check Design/Spec/Temprature SpecName Condenser TempStage Condenser Spec Value 100 oCUse As Estimate Check Design/Spec/Column Temperature

Name Reboiler TempStage Reboiler Spec Value 205 oCUse As Estimate Check Design/Specs/Duty Spec

Name Reboiler DutyEnergy Stream Reb QSpec Value 2.0e+007 kJ/hUse As Estimate Check Design/Specs/Comp Frac Spec

Name TEG PurityStage Reboiler

Phase LiquidSpec Value 0.95Components TEGlycolUse As Estimate Check ParametersCondenser Pressure [kPa] 110Reboiler Pressure [kPas] 150Condenser Delta Pressure [kPa] 15Parameters/SolveDamping Adaptive

Run

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Nhp dng Makeup TEG:

Worksheet/ConditionsName Makeup TEGTemperature [C] 15

CompositionComponent Mole FractionsH2O 0.01TEG 0.99

Nhp thit b trn MIX-100:

Design/ConnectionsName MIX-100

Inlet Learn from L/R Makeup TEG

Outlet TEG to PumpParametersAutomatic Pressure Asignment Equalize AllWorksheet/ConditionsMakeup TEGTemperature [C] 15

Nhp bm P-100:

Design/ConnectionsName P-100Inlet TEG to PumpOutlet Pump outEnergy Pump QDesign/ParameterAdiabatic Efficiency 75%

Worksheet/ConditionsPump outPressure [kPa] 6270TEG to PumpVol Flow [m3/h] 0.5

Thit b trao i nhit TEG-Ex:

Design/ConnectionsName TEG-ExTube Side Inlet Pump out

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Tube Side Outlet TEG to RecycleShell Side Inlet Dry GasShell Side Inlet Sale GasDesign/Parameter

Heat Exchanger Model Exchanger Design (Weighted)Tube Side/Delta P 70 kPaShell Side/Delta P 35 kPaWorksheet/ConditionsTEG to RecycleTemperature [oC] 35

Nhp thit b Recycle RCY-1:

Connections/ConnectionsName RCY-1Inlet TEG to RecycleOutlet TEG FeedParameters/VariablesComposition/Sensitivities 0.1

Kim tra im sng ca Slae Gas vi Hydrat Formation Utility

Three ways to attach Utilities to Sale Gas :

The first wayTool Utilities/Utilities view

The second wayPress Ctrl +U/ Utilities view

The last wayDouble -Click A StreamAttachments Utilities/Create button/Utilities view

Attach a Hydrate Formation Utility to Sale Gas

Utilities view

Design/Connections

Design/Connections/Hydrate CalculationModelPerformance/Formation T/PEquilibrium Phase

Hydrate Formation UtilityAdd UtilitySelect Stream buttonSale GasVapour Only Model

Vapour Phase

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Nhp thit b chit thnh phn Remove TEG:

Design/ConnectionsName Remove TEGInlets Sale GasOverhead Outlet TEG onlyBottoms Outlet Water DewpointEnergy Streams Split QWorksheet/ConditionsTEG onlyTemperature [C] 10Pressure [kPa] 6155

Nhp thit b tch Remove H2O:

Design/ConnectionsName Remove H2OInlet Water DewpointVapour Outlet Gas OutLiquid Outlet XS H2OWorksheet/ConditionsWater DewpointTemperature [C] -32.53

Pressure [kPa] 6155

Nhp thit b iu khin ADJ-1:

Connections/ConnectionsAdjust Name ADJ-1Adjusted VariableObject /Variable Water Dewpoint/TemperatureTarget Variable

Object/Variable/Variable Specifics XS-H2O/Master Comp Mass Flow/H2OTarget ValueSource User SuppliedSpecified Target Value 0.01 kg/hParameters/ParametersSolving ParametersMethod SecantStep Size 5 oCMinimum (Optional) -50 oCMaximum (Optional) 10 oC

Maximum Iterations 10

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3.2. Kt qu v nhn xtKt qu :

Dng Gas Out

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Nhn xt:

So snh kt qu tnh ton v m phng c s sai s ,tuy nhin l do tnh ton bng tayc s sai lch trong thc hin php tnh v lm trn

Tuy nhin dung sai nm trong gii hn cho php.

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Chng4. Ph lc

Hnh 1: PFD ca quy trnh tch nc dng kh t nhin bng dung mi hp th

TEG

Hnh 2: Thp hp th kh dng TEG

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Hnh 3: Thp ti sinh TEG

Hnh 4: Thng s hot ng ca cc thit b

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Hnh 5: Thnh phn ca cc dng nguyn liu v sn phm

Bng 1: iu kin hot ng ca cc dng

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Bng 2: Thnh phn ca cc dng

Bng 3: Cc dng nng lng

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Bng 4: Dng ca cc thit b

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Kt lunTrong qu trnh thc hin nhm t c mt s kt qu nh sau:

Tnh ton s b c qu trnh Dehydrate bng tay M phng thnh cng quy trnh Dehydrate s dng dung mi hp th l TEG

Tuy nhin vi thi gian hn ch nhm gp phi mt vn : Qu trnh ti sinh dung mi

hp th TEG vn cha t c tinh khit cao ( 90%).

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Ti liu tham kho

1. Bi ging tin ng dng - Ks. on Vn Hun

2. Advanced Process Modeling using Hysys - Aspentech

3. Aspen Hysys 2006 - Tutorial

bai tap lon nhom 4_duy

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