tính toán cân bằng vật chất và cân bằng nhiệt lượng của công nghệ ccr

7/22/2019 Tnh ton cn bng vt cht v cn bng nhit lng ca cng ngh CCR

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Tnh ton cn bng vt cht v cn bng nhit lng ca cng ngh CCR

BTL Cng ngh Ch bin du Page 1

MC LC

1. Cc s liu ban u.............................................................................................. 2

2. Tnh ton cc phn ng chnh xy ra trong qu trnh reforming xc

tc 2

2.1. Tnh nng sut thit b ......................................................................................... 5

2.2. Tnh lng kh tun hon cn thit ...................................................................... 6

2.3. Tnh ton phn b p sut ca cc cu t trong hn hp nguyn liu v thnh

phn kh tun hon....................................................................................................... 7

3. Tnh ton cho l th nht..................................................................................... 8

3.1. Tnh cn bng vt cht......................................................................................... 8

3.2. Tnh cn bng nhit lng ................................................................................. 12

4. Tnh ton cho l th 2 ....................................................................................... 15

4.1. Tnh ton cn bng vt cht ............................................................................... 15

4.2. Tnh ton cn bng nhit lng ......................................................................... 19

5. Tnh ton cho l th 3 ....................................................................................... 22

5.1. Tnh cn bng vt cht....................................................................................... 22


6. Tnh ton cho l th 4 ....................................................................................... 29

6.1. Tnh cn bng vt cht....................................................................................... 29



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1. Cc s liu ban uCng sut : 1.500.000 tn/ nm.

Nhit : 470 5300C.

Tc th tch : 1,5 h-1.

p sut : 3,5 kg/ cm2 = 343.234,5 pa.

T l H2/ RH : 2,5 kmol.

Phn b xc tc trong l phn ng ln lt l: 1/1,5/2,5/5.

Bng1: Thnh phn nguyn liu.

Khi lng ring Thnh phn phn on % khi lng

293

T0

su T0

s 10% T0

s 50% T0

s 90% T0

scui P N A

0,7288 3290K 348

0K 385

0K 428

0K 453

0K 50 38 12

2. Tnh ton cc phn ng chnh xy ra trong qu trnh reforming xc tc- Phn ng chnh chuyn ho hydrocacbon naphten thnh RH thm.

CnH2n CnH2n-6 + 3H2 (1)

- Phn ng chuyn ha hydrocacbon naphten thnh parafinCnH2n + H2 CnH2n+2 (2)

- Phn ng hydro cracking naphtenCnH2n + n/3 H2 n/15 (CH4 + C2H6 + C3H8 + C4H10 + C5H12) (3)

Ta c th m ta s gim hm lng hydrocacbon do chuyn ha ho hc cc

phn ng trn bng cc phng trnh vi phn sau :

(4)

(5)

277


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Me . yi = Mi . yi

Trong :

Me: khi lng phn t trung bnh ca nguyn liu .

Mi: khi lng phn t trung bnh ca cc hydrocacbon trong nguyn liu .

yi, yiln lt l phn khi lng v phn mol ca cu t i trong nguyn liu

Mt khc th M = 0,4.T50 - 45

Trong :

T50l nhit si ti 50% th tch ca nguyn liu .

Vy ta tnh c Me = 0,4 x 385 - 45 = 109 .

Bng 3: Khi lngca cc hydrocacbon trong nguyn liu.

Hydrocacbon Cng thc ha hc Cng thc khi lng

Parafin (P) CnH2n +2 Mp = 14n + 2

Naphaten (N) CnH2n MN = 14n

Aromatic (A) CnH2n - 6 MA = 14n - 6

Ngoi ra Me cn tnh theo cng thc :

Trong :

YP,YN,YA ln lt l phn khi lng ca cc hydrocacbon trong nguyn liu

MA MN , MP l khi lng phn t ca cc hydrocacbon: Aromatic, naphten v

parafin trong nguyn liu :

Me =1

YA YN YP

14n - 6 14n 14n+2++

Me =1

YA YN YP

MA MN MP++


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Bin i ta c phng trnh sau :

n3

- (Me + 4)n2

- [6 + ( YA - 2YN - 3 YP)Me]n + YNMe = 0

Gii phng trnh trn ta c n = 7,77

Vy khi lng phn t trung bnh ca cc hydrocacbon nh sau :

MP = 14n + 2 = 14x 7,77 + 2 = 110,78,

MN = 14n = 14 x 7,77 = 108,78,

MA = 14n - 6 = 14x 7,77 - 6 = 102,78,

Bng 4: Thnh phn ca nguyn liu.

Cu t Khi lng phn tHm lng trong nguyn liu

yiphn khi lng yi' =yi .Me/Mi

Cn H2n + 2 110,78 0,50 0,492

Cn H2n 108,78 0,38 0,381

Cn H2n6 102,78 0,12 0,127

Tng --- 1,000 1,000

2.1. Tnh nng sut thit bGc = L/(24 x 340) , kg/h.

Vi L: l nng sut nm, L = 1.500.000 tn/nm .

Trong s ngy hot ng trong nm l 340 ngy (c 25 ngy ngh sa

cha v bo dng thit b).

Vy ta tnh c nng sut ca thit b trn gi l :

Gc = (15x 108

)/(24 x 340) = 183.823,529 (kg/h)

Nng sut thit b tnh ra (Kmol/h)

NC = Gc/Me = 183.823,529 / 109 = 1686,454 (Kmol/h)


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Bng 5: Thnh phn cc cu t trong nguyn liu.

Cu t yi(phn mol) Ni = NC . y'i (kmol/h)

Cn H2n + 2 0,492 829,735

Cn H2n 0,381 642,539

Cn H2n - 6 0,127 214,180

Tng 1,000 1686,454

2.2. Tnh lng kh tun hon cn thitTa c H2/ RH = 2,5 Kmol.

Nng sut H2 l:

nH2 = 2,5 . NC = 2,5 x 1686,454 = 4216,135 (kmol/h).

Vy lng kh tun hon li l:

nkth = nH2 . 100/86 = 4216,135 x 100/86 = 4902,483 (kmol/h).

Bng 6: Thnh phn cc cu t trong kh tun hon.

Cu t Mi yi Mi . yi ni = nkth . yi

H2 2 0,86 1,72 4216,134

CH4 16 0,04 0,64 196,099

C2H6 30 0,05 1,50 245,124

C3H8 44 0,03 1,32 147,075

C4H10 58 0,01 0,58 49,025

C5H12 72 0,01 0,72 49,025

Tng - 1,00 6,48 4902,483

- Lng hydrocacbon trong kh tun hon l:P* = 4902,483 - 4216,135 = 686,348 (kmol/h).


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- Lng cht xc tc cho qu trnh l:Th tch xc tc: Vxt = Gc / c V0 (m

3)

Trong :

V0l tc th tch = 1,5h-1

C: Khi lng ring ca nguyn liu th lng. Ly C = 728,8 (kg/m3).

Lng xc tc: mXT = VXT .XT

Trong : XT khi lng ring xc tc;XT = 550 650 (kg/m3).Chn XT = 600

(kg/m3).

Suy ra mXT = 168,152 x 600 = 100.891,270 (kg).

2.3. Tnh ton phn b p sut ca cc cu t trong hn hp nguyn liu vthnh phn kh tun hon.

Ta c cng thc: Pi = P . y

i

Trong :

Pi: p sut ring phn cu t i [pa].

P: p sut chung ca l phn ng [pa].Chn P = 3,5 kg/cm2 = 343234,5 (pa).

yi: nng phn mol ca cu t i trong hn hp.

Bng 7: Thnh phn p sut.

Cu t ni (Kmol/h) y'i = ni/ ni Pi= 343.234,5. y'i (Pa)

P 829,735 0,1259 43213,223

N 642,539 0,0975 33465,364

A 214,180 0,0325 11155,121

H2 4216,135 0,6399 219635,757

P*

686,348 0,1040 35765,035

Tng 6588,937 1,0000 343.234,500


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Phn b xc tc trong cc l phn ng theo t lnh sau: 1/1,5/2,5/5.

Bng 8: S phn b xc tc trong cc l phn ng.

L phn ng VXT ( m ) MXT = VXT x 600 (kg)

1 16,8152 10089,12

2 25,2228 15133,68

3 42,0380 25222,80

4 84,0760 50445,60

Tng 168,1520 100.891,20

3. Tnh ton cho l th nht3.1. Tnhcn bng vt cht

Hng s tc phn ng chuyn ho naphten thnh aromatic.

T = 8030K 1000/ T = 1000/803 = 1,245

Tra th ph lc [1] ta c K1 = 11. 10-7

(kmol/h.pa3.kg xc tc).

Phng trnh tnh hng s cn bng phn ng:

KP1 = 9,813

. 1012

. e46,15 - 25600/T

= 9,813

. 1012

. e46,15 - 25600/803

= 14,866 . 1020

(pa3).

gim tng i hm lng naphten do phn ng thm ho (phn ng 1).

M VR1 = mxt 1/NC

Trong : mxt 1 = 10089,120 (kg)

NC: Lng nguyn liu vo l phn ng th nht (kmol/h).

VR1 = 10089,120 / 1686,454 = 5,9824 (kg/kmol).

Vy: N1 = 0,0368 x 5,9824 = 0,2202

dN1dVR1

H2K1 . PA .P3

KP1

= K1. PN = 0,0368


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Lng naphten tham gia phn ng (1) l:

nN1 = 0,2202 x 1686,454 = 371,273 (kmol/h)

Vy lng naphten cn li sau phn ng (1) l.

nN1 = ( yi - N1) x NC = ( 0,381 - 0,2202 )x 1686,454 = 271,266 (kmol/h)

Hngs tc phn ng chuyn ho naphten thnh parafin (2)T = 8030K

1000/T = 1000/803 = 1,245

Tra th ph lc [2] ta cK2 = 100.10-15

(kmol/h.kg xc tc).

KP2 = 98,1-1

. 10-3

. e(4450/T) - 7,12

= 98,1-1

. 10-3

. e(4450/803) - 7,12

= 0,0021.10-3

[pa-1

].

Do KP2


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Bng9:Cn bng ho hc cho l phn ng th nht.

Lng cht tham gia phn ng (kmol/h) Lng sn phm (kmol/h)

371,273 CnH2n 371,273 CnH2n - 6 + 371,273x 3H2

20,760CnH2n+2 20,760CnH2n + 20,760H2

Bng10:Tnh lng cht dng vo v dng ra ca l phn ng th nht.

Cu t Lng vo(kmol/h) Lng ra (kmol/h)

P 829,735 829,735 - 20,76 = 808,975

N 642,539 642,539 - 371,273 + 20,76 = 292,026

A 214,180 214,180 + 371,273 = 585,453

Tng 1686,454 1686,454

Bng11:Tnh lng kh tun hon.

H2 4216,135 4216,135 + 371,273x3 + 20,76 = 5350,714

CH4 196,099 196,099

C2H6 245,124 245,124

C3H8 147,075 147,075

C4H10 49,025 49,025

C5H12

49,025 49,025

Tng 4902,483 6037,062

Lng kh tun hon:

( 5350,714 + 686,348 )x 5,637 = 34030,918 (kg/h)

Lng hydrocacbon trong kh tun hon l:

215594,945 - 34030,18 = 181564,027 (kg/h)

Vy ta c phng trnh sau:


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585,453x(14n - 6) + 292,026x14n + 808,975x(14n + 2) = 181564,027

suy ra n = 7,7703

MA = 14n - 6 = 14 x 7,7703 - 6 = 102,784

MN = 14n = 14 x 7,7703 = 108,784

MP = 14n +2 = 14 x 7,7703 + 2 = 110,784

Bng 12: Lng kh tun hon ra khi l phn ng th nht.

Cu t Mi ni (kmol/h) y'i = n'i/ni Miy'i

H2 2 5350,714 0,8863 1,773

CH4 16 196,099 0,0325 0,520

C2H6 30 245,124 0,0406 1,218

C3H8 44 147,075 0,0244 1,074

C4H10 58 49,025 0,0081 0,469

C5H12

72 49,025 0,0081 0,583

Tng - 6037,062 1,0000 5,637

Bng13:Cn bng vt cht ca l phn ng th nht.

Cu t ni (kmol/h) yi Mi Gi = Mi . ni

u vo

P 829,735 0,1259 110,780 91918,043

N 642,539 0,0975 108,780 69895,392

A 214,180 0,0325 102,780 22013,420

H2 4216,135 0,6399 6,480 27320,555

P* 686,348 0,1042 6,480 4447,535

Tng 6588,937 1,0000 - 215594,945

u ra

P 808,975 0,1050 110,784 89621,486


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N 292,026 0,0378 108,784 31767,756

A 585,453 0,0758 102,784 60175,201

H2 5350,714 0,6930 5,637 30161,975

P* 686,348 0,0889 5,637 3868,944

Tng 7723,516 1,0000 - 215594,945

3.2. Tnh cn bng nhit lngTa c phng trnh cn bng nhit lng:

Q11 + Q21 = Q31 + Q41 + Q51 + Q61

Trong :

Q11: Nhit lng hn hp kh nguyn liu v kh tun hon mang vo (kj/h)

Q21: Nhit lng do xc tc mang vo l phn ng (kj/h)

Q31: Nhit lng do kh sn phm v kh tun hon mang ra khi l phn ng

(kj/h).

Q41: Nhit lng do xc tc mang ra khi l phn ng (kj/h);

Q51: Nhit lng tn tht do phn ng reforming (kj/h).

Q61: Nhit lng mt mt ra mi trng bn ngoi (kj/h).

Tnh Q21:Q21 = mXT . q21 = mXT. CPxt .T

Trong :

q21 = CPxt.T : hm nhit xc tc (kj/h)

CPxt: nhit dung ring ca xc tc nhit T(0

K)CPxt = a0 + a1.T - a2. T

-2(kj/kgh)

Tra s tay ho l CPxt(Al203)

CPxt = 22,08 + 8,971.10-3

.T - 5,225. 105T

-2

Ti nhit T = 8030K thay vo ta c

CPxt = 28,473 (kcal/kmol) = 1,1685 (kj/kg.0K)

q21 = CPxt.T = 1,1685 x 803 = 938,3055(kj/kg)

Vy Q21 = mxt 1 .q21 = 10089,12 x 938,3055 = 9466676,786 (kj/h)


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Tnh Q41: Gi thit nhit ti l phn ng th nht gim iT = 700KQ41 = mXT2. CPxt .T

Trong : mxt2lng xc tc ra khi l phn ng th nht.

CPxt: Nhit dung ring xc tc T = 803 - 70 = 7330K

CPxt = 22,08 + 8,91.10-3

x 733 - 5,225.105x(733)

-2 = 28,654 (kcal/kmol.

0K)

CPxt = 1,1759 (kj/kg.0K)

Q41 = mxt 1CPxt.T = 10089,12 x 1,1759 x 733 = 8696162,62 (kj/h)

Tnh Q11: Ta cn xc nh entanpi ca dng hi nguyn liu ca vo ca lphn ng th nht.

S liu entanpi ca H2, CH4, C2H6, C3H8, C4H10, C5H12 tra s tay ho l. xc nh entanpi ca aromatic, naphten, parafin, ta da vo trng lngphn t trung

bnh ca cc cu t

Bng 14: T trng ca cc cu t.

Cu tu vo u ra

P 0,733 0,737

N 0,721 0,733

A 0,718 0,722

tnh hiu ng nhit ca cc phn ng ta dng cng thc sau:

qP = - 355.b

Trong : b. hiu sut to hydro tinh khit theo khi lng nguyn liu ban u (%

kl).

NH2 = 5350,714 - 4216,135 = 1134,579 (kmol/h)

GH2 = MH2 .1134,579 = 1134,579 x 2 = 2269,158 (kg/h)

b = GH2100%/GC = 2269,158 x 100%/183823,529 = 1,23%

Vy qp = - 355 . b = - 355 x 1,23 = - 436,65 (KJ/kg)

Nhit lng do hm hp nguyn liu v kh tun hon mang vo l phn ng thnht.

298298


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Q11 = Gc . qtr1 = 1908,71x 215594,945 = 411508227,5 (kj/h)

Bng 15: Entanpi ca hn hp hi vo l phn ng th nht.

Cu t Mi niy'i =

ni/ niMi.y'i

yi =

Miy'/Miy'i

Entanpi

qt

(KJ/kg)

qtyi

(KJ/h)

H2 2 4216,135 0,6400 1,280 0,0319 7700 301,07

CH4 16 196,099 0,0298 0,477 0,0146 1618 23,62

C2H6 30 245,124 0,0371 1,113 0,0339 1434 48,76

C3H8 44 147,075 0,0223 0,981 0,0300 1405 42,15

C4H10 58 49,025 0,0074 0,432 0,0132 1400 18,48

C5H12

72 49,025 0,0074 0,536 0,0160 1392 22,27

A 102,78 214,180 0,0325 3,340 0,1020 1715 174,93

N 108,78 642,539 0,0975 10,606 0,3240 1704 552,10

P 110,78 829,735 0,1226 13,958 0,4260 170,3 725,48

Tng - 6588,937 1,0000 32,723 1,0000 - 1908,71

Tnh Q61. Nhit lng mt mt ra mi trng bn ngoi.Q61 = 0,01 x(Q11 + Q 21) = 0,01x(9466676,786 + 411508227,5)

= 4209749,04 (kj/h)

Tnh Q51. Nhit lng tiu tn do phn ng reforming.Q51 = Gc.qP = 436,65 x 183823,529 = 80266543,94 (kj/h).

Tnh Q31 . Nhit lng do sn phm v kh tun hon mang ra.Q31 = Q11 + Q21 - Q41 - Q51 - Q61

Q31 = 411508227,5 + 9466676,786 - 8696162,62 - 80266543,94

- 4209749,04 = 335602448,4(kj/h)

Q31 = 335602448,4 (kj/h); m ta c Q31 = 215594,945 qtr1

qtr1 = 1556,634 (kj/h)


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qtr1: hm nhit ca sn phm v kh tun hon mang ra.

Bng 16: Cn bng nhit lng ca l phn ng th nht .

Dng Nhit (oK) Lng (Kg/h) Entanpi (KJ/kg) Nhit lng(KJ/h)

Dng vo

Q11 803 215594,945 1908,710 411508227,5

Q21 803 9466676,8

Tng --- --- --- 420974904,3

Dng ra

Q31 733 215594,945 1556,634 335602448,4

Q41 733 8696162,7

Q51 733 80266543,9

Q61 4209749,3

Tng --- --- --- 420974904,3

4. Tnh ton cho l th 24.1. Tnh ton cn bng vt cht

Bng 17: Thnh phn cc cu t ca l phn ng th hai.

Cu t nc (kmol/h) yC2i = nci/nc2i

Cn H2n + 2 808,975 0,4797

Cn H2n 292,026 0,1732

Cn H2n - 6 585,453 0,3471

Tng 1686,454 1,0000

gim psut gia cc l phn ng thng 0,15 0,35 (kg/cm2). Chn gim

p sut l phn ng th hai l 0,2 (kg/cm2). Khi p sut chung ca hn hp kh

nguyn liu vo l phn ng th hai l:

P2 = 3,5 - 0,2 = 3,3 (kg/cm2) = 3,3 x 98067 = 323621,1 (pa)


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Cu t y'i = ni/ ni Pi = 323621,1. y'i (Pa)

P 0,105 33980,22

N 0,037 11973,98

A 0,076 24595,20

H2 0,693 224269,42

P*

0,089 28802,28

Tng 1,000 323621,10


Ta c nhit u vo ca l phn ng th hai l T = 8030K

T = 8030K 1000/ T = 1000/803 = 1,245

Tra th ph lc [1] ta c K1 = 11. 10-7



KP1 = 9,813

. 1012

. e46,15 - 25600/T

= 9,813 . 1012 . e46,15 - 25600/803

= 14,866 . 1020

(pa3).

gim tng i hm lng naphten do phn ng thm ho:

M VR2 = m2/NC

Trong :

mxt2 : lng xc tc vo l phn ng th hai; mxt2 = 15133,68 (kg)

NC: Lng nguyn liu vo l phn ng th hai (kmol/h).

VR2 = 15133,68/1686,454 = 8,974 (kg/kmol).

Vy N21 = 0,01317 x 8,974 = 0,1185 (kmol/h)


dN12

dVR2

K1 . PA .P3

KP1H2= K1. PN = 0,01317


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nN12 = 0,1185 x 1686,454 = 199,845 (kmol/h)

Hng s tc phn ng chuyn ho naphten thnh parafin T = 8030K

Tra th ph lc [2] ta cK2 = 100.10-15

(kmol/h.Pa2

kg xc tc).

KP2 = 98,1-1

. 10-3

. e(4450/T) - 7,12

= 98,1-1

. 10-3

. e(4450/803) - 7,12

= 0,0021.10-3

[pa-1

].

Do KP2


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Bng 21: Tnh lng kh tun hon.

H2 5350,714 5350,714 + 199,845x3 + 25,803= 5976,052

CH4 196,099 196,099

C2H6 245,124 245,124

C3H8 147,075 147,075

C4H10 49,025 49,025

C5H12

49,025 49,025

Tng 6037,062 6662,400

Bng 22: Kh tun hon ra khi l phn ng th hai.


H2 2 5976,052 0,8970 1,794

CH4 16 196,099 0,0294 0,470

C2H6 30 245,124 0,0368 1,104

C3H8 44 147,075 0,0220 0,968

C4H10 58 49,025 0,0074 0,429

C5H12

72 49,025 0,0074 0,533

Tng - 6662,400 1,0000 5,299

Lng kh tun hon:

(5976,052 + 686,348) x 5,299 = 35304,058 (kg/h)


215594,945 - 35304,058 = 180290,887 (kg/h)

Vy ta c phng trnh sau;

785,298 x(14n - 6) + 117,984 x14n + 783,172 x(14n + 2) = 186746,753

suy ra n = 7,769

MA = 14n - 6 = 14x 7,769 - 6 = 102,766

MN = 14n = 14 x 7,769 = 108,766


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MP = 14n +2 = 14 x7,769+ 2 = 110,766

Bng 23: Cn bng vt cht ca l phn ng th hai.


u vo

P 808,975 0,105 110,784 89621,487

N 292,026 0,039 108,784 31767,756

A 585,453 0,076 102,784 60175,202

H2 5350,714 0,692 5,637 30161,976

P* 686,348 0,088 5,637 3868,944

Tng 7723,516 1,000 - 215594,945

u ra

P 783,172 0,094 110,766 86748,30

N 117,984 0,014 108,766 12832,648

A 785,298 0,094 102,766 80701,934

H2 5976,052 0,716 5,299 31667,099

P* 686,348 0,082 5,299 3636,956

Tng 8348,854 1,000 215594,922

4.2. Tnh ton cn bng nhit lngTa c phng trnh cn bng nhit lng:

Q12 + Q22 = Q32 + Q42 + Q52 + Q62

Trong :



Q32: Nhit lng do kh sn phm v kh tun hon mang ra (kj/h).

Q42: Nhitlng do xc tc mang ra khi l phn ng (kj/h);


Q62: Nhit lng mt mt ra mi trng bn ngoi (kj/h).Tnh Q22:


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Nhit lng Q22do xc tc mang vo l phn ng th hai chnh l nhit lng

do xc tc mang ra khi l phn ng th nht.

Q22 = Q41 = 8696162,62 (kj/h)

Tnh Q42Gi thit nhit ti l phn ng th hai gim iT = 600K

Q42 = mXT2. CPxt .T

Trong : mxt2lng xc tc ra khi l phn ng th hai.

CPxt: nhit dung ring xc tc T = 803 - 60 = 7430K

CPxt = 22,08 + 8,91.10-3

x 743 - 5,225.105x(743)

-2 = 27,80 (kcal/kmol.

0K)

CPxt = 27,80 x 4,186 /102 = 1,1409 (kcal/kg

0

K)Q42 = mxt2CPxt.T = 15133,68 x 1,1409 x 743 = 12828649,53 (kj/h)

Tnh Q12: Ta cn xc nh entanpi ca dng hi nguyn liu ca vo l phnng th hai.

Bng 24: Entanpi ca hn hp hi vo l phn ng th hai .

Cu t Mi niy'i =

ni/ niMi.y'i

yi =

Miy'/Miy'i

Entanpi

qt

(KJ/kg)

qtyi

(KJ/h)

H2 2 5350,714 0,6928 1,387 0,0497 7700 382,69

CH4 16 196,099 0,0254 0,406 0,0146 1618 23,62

C2H6 30 245,124 0,0317 0,951 0,0341 1434 48,90

C3H8 44 147,075 0,0190 0,836 0,0299 1405 42,01

C4H10 58 49,025 0,0063 0,359 0,0129 1400 18,06

C5H12

72 49,025 0,0063 0,454 0,0163 1392 22,69

A 102,784 585,453 0,0758 7,791 0,2793 1715 479,00

N 108,784 292,026 0,0378 4,112 0,1474 1704 251,17

P 110,784 808,975 0,1047 11,599 0,4158 1703 708,11

Tng - 7723,516 1,0000 27,894 1,0000 1976,25



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qP = - 355.b

Trong : b. hiu sut to hydro tinh khit theo khi lng nguyn liu ban u (%

kl).

NH2 = 5976,052 - 5350,714 = 625,338 (kmol/h)

GH2 = MH2 . 625,338 = 2 x 625,338 = 1250,676 (kg/h)

b = GH2 100%/GC = (1250,676 x100%)/183823,529 = 0,68%

Vy qp = - 355 . b = - 355 x 0,68 = - 241,40 (KJ/kg)

Nhit do hm hp nguyn liu v kh tun hon mang vo l phn ng th hai.

Q12 = 216538,301 x 1976,25 = 426069508,10 (kj/h)

Tnh Q62. Nhit mt mt ra mi trng bn ngoi. Q62 = 0,01 x(Q22 + Q 21) = 0,01x (426069508,10 + 8696162,62)

= 5130356,71 (kj/h)

Tnh Q52. Nhit lng tiu tn do phn ng reforming.Q52 = Gc.qP = 183823,529 x 241,40 = 44374999,90 (kj/h).

Tnh Q32 .Nhit lng do sn phm v kh tun hon mang ra.Q32 = Q12 + Q22 - Q42 - Q52 - Q62

Q32 = 426069508,10 + 8.696.162,62 - 12828649,53 - 44374999,90

- 5130356,71 = 326258455,6 (kj/h)

Q32 = 215594,922 qtr2

qtr2 = 1513,294 (kj/h)


Bng25:Cn bng nhit lng ca l phn ng th hai .

Dng Nhit (oK) Lng (Kg/h) Entanpi (KJ/kg) Nhit lng (KJ/h)

Dng vo

Q12 803 215594,945 1976,25 426069508,10

Q22 803 8696162,62

Tng 434765670,70


22/36



Dng ra

Q32 743 215594,922 1513,294 326258455,6

Q42 743 12828649,53

Q52 743 44374999,90

Q62 743 5130356,71

Tng 434765670,70

5. Tnh ton cho l th 35.1. Tnh cn bng vt cht

Bng 26: Thnh phn cc cu t ca l phn ng th ba.

Cu t nc (kmol/h) yC2i = nci/nc2i

Cn H2n + 2 783,172 0,464

Cn H2n 117,984 0,070

Cn H2n - 6 785,298 0,466

Tng 1686,454 1,000

gim p sut gia cc l phnng thng 0,15 0,35 (kg/cm2). Chn gim

p sut l phn ng th ba l 0,2 (kg/cm2). Khi p sut chung ca hn hp kh

nguyn liu vo l phn ng th ba l:

P3 = 3,3 - 0,2 = 3,1 (kg/cm2) = 3,1 x 98067 = 304007,7(pa)


Cu t y'i Pi = 304007,7y'i (Pa)

P 0,0938 28515,922

N 0,0141 4286,509

A 0,0941 28607,125

H2 0,7158 217608,712

P*

0,0822 24989,433

Tng 1,0000 304007,700


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Ta c nhit u vo ca l phn ng th ba l T = 8030K

T = 8030

K 1000/ T = 1000/803 = 1,245

Tra th ph lc [1] ta c K1 = 11. 10-7



KP1 = 9,813

. 1012

. e46,15 - 25600/T

= 9,813

. 1012

. e46,15 - 25600/803

= 14,866 . 1020

(pa3).


M VR3 = mxt3/NC

Trong :

mxt3: lng xc tc vo l phn ng th ba; mxt3 = 25222,8 (kg)NC: Lng nguyn liu vo l phn ng th ba (kmol/h).

VR3 = 14,956 (kg/kmol).

Vy N13 = 14,956 x 0,004715 = 0,07052 (kmol/h)


nN13 = NC x 0,07052 = 0,07052 x 1686,454 = 118,929 (kmol/h)


Tra th ph lc [2] ta cK2 = 100.10-15

(kmol/h.Pa2

kg xc tc).

KP2 = 98,1-1

. 10-3

. e(4450/T) - 7,12

= 98,1-1

. 10-3

. e(4450/803) - 7,12

= 0,0021.10-3

[pa-1

].

Do KP2


24/36



Suy ra N N23 = 0,001358x 14,956 = 0,0203

Hm lng naphten to thnh do phn ng (2) l.

nN23 = 0,0203 x 1686,454 = 34,235 (kmol/h)

Lng naphten sau phn ng (1) v (2) l.

nN23 = (yN3 - NN13 + NN23)Nc = (0,070 - 0,07052 + 0,0203)x1686,454

= 33,29 ( kmol/h)

Bng 28: Cn bng ho hc ca l phn ng th ba.

Lng cht tham gia phn ng (kmol/h) Lng sn phm (kmol/h)

118,929 CnH2n 118,929 CnH2n - 6 +118,929 x 3H2

34,235 CnH2n+2 34,235 CnH2n + 34,235 H2

Bng 29: Tnh lng cht dng vo v dng ra l phn ng th ba.


P 783,172 783,172 - 34,235 = 748,937

N 117,984 117,984 - 118,929 + 34,235 = 33,29

A 785,298 785,298 + 118,929 = 904,227

Tng 1686,454 1686,454

Lng khi tun hon l: (6367.074 + 686,348 ) x 5,102 = 35986,559 (kg/h)

Lng hydrocacbon trong kh tun hon:

215594,922 - 35986,559 = 179608,363 (kg/h)


904,227x(14n - 6) + 33,29x14n + 748,937x(14n + 2) = 179608,363


25/36



suy ra n = 7,774

MA = 14n - 6 = 14x - 6 = 14 x 7,774 - 6 = 102,836

MN = 14n = 14 x 7,774 = 108,836

MP = 14n +2 = 14x + 2 = 14 x 7,774 + 2 = 110,836

Bng 30: Tnh lng kh tun hon.

H2 5976,052 5976,052 + 3x118,929 +34,235 = 6367.074

CH4 196,099 196,099

C2H6 245,124 245,124

C3H8 147,075 147,075

C4H10 49,025 49,025

C5H12

49,025 49,025

Tng 6662,400 7053,422

Bng 31: Kh tun hon ra khi l phn ng th ba.


H2 2 6367,074 0,9030 1,806

CH4 16 196,099 0,0277 0,443

C2H6 30 245,124 0,0347 1,041

C3H8 44 147,075 0,0208 0,915

C4H10 58 49,025 0,0069 0,400

C5H12

72 49,025 0,0069 0,497

Tng - 7053,422 1,0000 5,102


26/36



Bng 32: Cn bng vt cht ca l phn ng th ba.


u vo

P 783,172 0,094 110,766 86748,30

N 117,984 0,014 108,766 12832,648

A 785,298 0,094 102,766 80701,934

H2 5976,052 0,716 5,299 31667,099

P* 686,348 0,082 5,299 3636,956

Tng 8348,854 1,000 215594,922

u ra

P 748,937 0,0857 110,836 83009,181

N 33,29 0,0037 108,836 3623,150

A 904,227 0,1035 102,836 92987,088

H2 6367,074 0,7285 5,102 32484,812

P* 686,348 0,0785 5,102 3439,976

Tng 8739,874 1,0000 215594,207

5.2. Tnh cnbng nhit lngTa c phng trnh cn bng nhit lng:

Q13 + Q23 = Q33 + Q43 + Q53 + Q63

Trong :



Q33: Nhit lng do kh sn phm v kh tun hon mang ra (kj/h).

Q43: Nhit lng do lng xc tc mang ra khi l phn ng (kj/h);


Q63: Nhit lng mt mt ra mi trng bn ngoi (kj/h).


27/36



Tnh Q23: Nhit lng Q23do xc tc mang vo l phn ng th ba chnh lnhit lng do xc tc mang ra khi l phn ng hai.

Q23 = Q42 = 12828649,53 (kj/h)

Tnh Q43 Gi thit nhit ti l phn ng th ba gim iT = 500KQ43 = mXT3. CPxt .T

Trong : mxt3lng xc tc ra khi l phn ng th ba.


CPxt = 22,08 + 8,91.10-3

x 753 - 5,225.105x(753)

-2 = 27,9137 (kcal/kmol.

0K)

CPxt = 27,91370 x 4,186 /102 = 1,1456 (kcal/kg0K)

Q43 = mxt3CPxt.T = 753x 1,1456 x 25222,8 = 21758115,48 (kj/h)Tnh Q13: Ta cn xc nh entanpi ca dng hi nguyn liu ca vo ca lphn ng th ba.

Bng34:Entanpi ca hn hp hi vo l phn ng th ba.

Cu t Mi niy'i =

ni/ niMi.y'i

yi =

Miy'/Miy'i

Entanpi

qt

(KJ/kg)

qtyi

(KJ/h)H2 2 5976,052 0,7158 1,4344 0,0558 7700 429,66

CH4 16 196,099 0,0235 0,3728 0,0145 1618 23,46

C2H6 30 245,124 0,0294 0,8760 0,0342 1434 49,04

C3H8 44 147,075 0,0176 0,7700 0,0299 1405 42,01

C4H10 58 49,025 0,0059 0,3422 0,0133 1400 18,62

C5H12

72 49,025 0,0059 0,4248 0,0165 1392 22,97

A 102,766 785,298 0,094 9,7853 0,3807 1709 650,62

N 108,766 117,984 0,0141 1,4034 0,0546 1702 92,93

P 110,766 783,172 0,0938 10,292 0,4005 1698 680,05

Tng - 8348,854 1,0000 25,701 1,0000 - 2009,36


qP = - 355.b


28/36



Trong :b. hiu sut to hydro tinh khit theo khi lng nguyn liu ban u (% kl).

NH2 = 6019,750 - 5976,052 = 43,698 (kmol/h)

GH2 = MH2 . 43,698 = 2x 43,698 = 87,396 (kg/h)

b = GH2 100%/G = (87,396 x100%)/183823,529 = 0,0475%

Vy qp = - 355 . b = - 355 x 0,0475 = 16,863 (KJ/kg)

Nhit lng do hm hp nguyn liu v kh tun hon mang vo l phn ng th

ba.

Q13 = GC. qP = 2009,36 x215594,207 = 433207858,70 (kj/h)

Tnh Q63: Nhit lng mt mt ra mi trng bn ngoi.Q63 = 0,01 x(Q13 + Q 23) = 0,01x (433207858,70 + 12828649,53)

= 4460365,08 (kj/h)

Tnh Q53:Nhit lng tiu tn do phn ng reforming.Q53 = Gc.qP = 16,863 x 183823,529 = 3099816,14 (kj/h).

Tnh Q33 :Nhit lng do sn phm v kh tun hon mang ra.Q33 = Q13 + Q23 - Q43 - Q53 - Q63

Q33 = 433207858,70 + 12828649,53 - 21758115,48 - 3099816,17

- 4460365,08 = 416718211,50 (kj/h)

Q33 = 215594,922 qtr3

qtr3 = 1932,88 (kj/h)


Bng35:Cn bng nhit lng ca l phn ng th ba .


Dng vo

Q13 803 215594,922 2009,36 433207858,70

Q23 803 12828649,53

Tng - - - 446036508,20

Dng ra

Q33 753 215594,207 1932,88 416718211,50


29/36



Q43 753 21758115,48

Q53 753 3099816,14

Q63 753 4460365,08

Tng - - - 446036508,20

6. Tnh ton cho l th 46.1. Tnh cn bng vt cht

Bng 36: Thnh phn cc cu t ca l phn ng th t.

Cu t nc (kmol/h) YC2i = nci/nc2iCn H2n + 2 748,937 0,4441

Cn H2n 33,290 0,0197

Cn H2n - 6 904,227 0,5362

Tng 1686,454 1,0000

gim p sut gia cc l phn ng thng 0,15 0,35 (kg/cm2). Chn gim

p sut l phn ng th t l 0,2 (kg/cm2). Khi p sut chung ca hn hp kh

nguyn liu vo l phn ng th t l:

P4 = 3,1 - 0,2 = 2,9 (kg/cm2) = 2,9 x 98067 = 284394,3(pa)


Cu t y'i Pi =284394,30. y'i (Pa)P 0,0857 24372,59

N 0,0038 1080,76

A 0,1035 29434,81

H2 0,7285 207181,25

P*

0,0785 22324,96

Tng 1,0000 284394,30


30/36




Ta c nhit u vo l phn ng th t l T= 8030K

T = 8030K 1000/ T = 1000/803 = 1,245

Tra th ph lc [1] ta c K1 = 11. 10-7



KP1 = 9,813

. 1012

. e46,15 - 25600/T

= 9,813

. 1012

. e46,15 - 25600/803

= 14,866 . 1020

(pa3).


M VR4 = mxt4/NC

Trong :

mxt4: lng xc tc vo l phn ng th t; mxt4 = 50445,60 (kg)

NC: Lng nguyn liu vo l phn ng th t (kmol/h).

VR4 = 50445,60 /1686,454 = 29,912 (kg/kmol).

Vy N14 = 0,00119 x VR4 = 0,00119 x 29,912 = 0,0356 (kmol/h)


nN14 = NC x 0,0356 = 0,0356 x1686,454 = 60,038 (kmol/h)


Tra th ph lc [2] ta cK2 = 100.10-15

(kmol/h.Pa2

kg xc tc).

Phng trnh tnh hngs cn bng phn ng:

KP2 = 98,1-1

. 10-3

. e(4450/T) - 7,12

= 98,1-1

. 10-3

. e(4450/803) - 7,12

= 0,0021.10-3

[pa-1

].

dN14

dVR4

K1 . PA .P3

KP1H2= K1. PN = 0,00119


31/36



Do KP2


32/36



NH2 = 164,429 x n/3 =164,429 x(7,774 - 3)/3 = 261,661 (kmol/h).

Lng kh hydrocacbon sinh ra trong l phn ng th t l.

RH = 164,429 x n/15 = 164,429 x 7,774 /15 = 85,218 (kmol/h).

Bng 39: Tnh lng cht dng vo v dng ra ca l phn ng th t.


P 748,937 748,937 - 58,520 - 164,429 = 529,988

N 33,290 33,290 - 60,038 + 58,520 = 31,772

A 904,227 904,227 + 60,038 = 964,265

Tng 1686,454 1526,025

Bng 40: Kh tun hon.

H2 6367,074 6367,074+60,038x3+58,520-261,661 = 6344,047

CH4 196,099 196,099 + 85,218 = 281,317

C2H6 245,124 245,124 + 85,218 = 330,342

C3H8 147,075 147,075 + 85,218 = 232,293C4H10 49,025 49,025 + 85,218 = 134,243

C5H12

49,025 49,025 + 85,218 = 134,243

Tng 7053,422 7456,485

Bng 41: Kh tun hon ra khi l phn ng th t.


H2 2 6344,047 0,851 1,702

CH4 16 281,317 0,038 0,608

C2H6 30 330,342 0,044 1,320

C3H8 44 330,342 0,0311 1,364

C4H10 58 232,293 0,018 1,044

C5H12

72 134,243 0,018 1,296


33/36



Tng - 7456,485 1,0000 7,334

Lng kh tun hon l:

(1112,438 + 6344,047) x 7,334 = 5485,861 (kg/h)


215594,207 - 5485,861 = 160908,346 (kg/h)


964,265 x(14n - 6) + 31,772 x14n + 529,988x(14n + 2) = 160908,346

suy ra n = 7,7528

MA = 14n - 6 = 14 x 7,7528 - 6 = 102,529

MN = 14n = 14 x7,7528 = 108,529

MP = 14n +2 = 14 x7,7528 + 2 = 110,529

Bng 42: Cn bng vt cht ca l phn ng th t.


u vo

P 748,937 0,0857 110,836 83009,181

N 33,29 0,0037 108,836 3623,150

A 904,227 0,1035 102,836 92987,088

H2 6367,074 0,7285 5,102 32484,812

P* 686,348 0,0785 5,102 3439,976

Tng 8739,874 1,0000 215594,207

u ra

P 529,988 0,0591 110,529 58584,344

N 31,772 0,0035 108,529 3448,501

A 964,265 0,1073 102,529 98874,769

H2 6344,047 0,7063 7,334 46527,241

P* 1112,438 0,1238 7,334 8158,620

Tng 8982,510 1,0000 215593,475


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6.2. Tnh cn bng nhit lngTa c phng trnh cn bng nhit lng:

Q14 + Q24 = Q34 + Q44 + Q54 + Q64

Trong :

Q14: Nhit do hn hp kh nguyn liu v kh tun hon mang vo (kj/h)


Q34: Nhit do kh sn phm v kh tun hon mang ra (kj/h).

Q44: Nhit do lng xc tc mang ra khi l phn ng (kj/h);

Q54: Nhit tn tht do phn ng reforming (kj/h).

Q64: Nhit mt mt (kj/h).Tnh Q24:

Nhit lng Q24do xc tc mang vo l phn ng th t chnh l nhit lng do

xc tc mang ra khi l phn ng ba.

Q24 = Q43 = 21758115,48 (kj/h)

Tnh Q44 Gi thit nhit ti l phn ng th t gim iT = 400KQ44 = mXT4. CPxt .T

Trong : mxt4lng xc tc ra khi l phn ng th t.


CPxt = 22,08 + 8,971.10-3

x 763 - 5,225.105x(763)

-2 = 29,5 (kcal/kmol.

0K)

CPxt = 29,5 x 4,186 /102 = 1,2107 (kcal/kg0K)

Q44 = mxt4CPxt.T = 1,2107 x763x50445,60 = 46599834,28 (kj/h)

Tnh Q14: Ta cn xc inh entanpi ca dng hi nguyn liu vo l phn ngth t.

Bng 43: Entanpi ca hn hp hi vo l phn ng th t.

Cu t Mi niY'i =

ni/ niMi.y'i

yi =

Miy'/Miy'i

Entanpi

qt

(KJ/kg)

qtyi

(KJ/h)

H2 2 6367,074 0,7285 1,457 0,059 7700 454,30

CH4 16 196,099 0,0224 0,358 0,0145 1618 23,46


35/36



C2H6 30 245,124 0,0281 0,843 0,0342 1434 49,04

C3H8 44 147,075 0,0168 0,739 0,0299 1405 42,01

C4H10 58 49,025 0,0056 0,325 0,0132 1400 18,48

C5H12

72 49,025 0,0056 0,403 0,0162 1392 22,69

A 102,836 904,227 0,1035 10,644 0,4312 1700 733,04

N 108,836 33,29 0,0038 0,414 0,0168 1695 28,48

P 110,836 748,937 0,0857 9,499 0,3849 1690 650,48

Tng - 8739,874 1,0000 24,682 1,0000 - 2021,98


qP = - 355.b

Trong :b. hiu sut to hydro tinh khit theo khi lng nguyn liu ban u (% kl).

NH2 = 60,038 x3 + 58,520 = 238,634 (kmol/h)

GH2 = MH2 . 238,634 = 238,634 x2 = 477,268 (kg/h)

b = GH2 100%/GC = 477,268 x100%/183823,529 = 0,260 %

Vy qp = - 355 . b = - 355x 0,260 = 92,30 (KJ/kg)

Nhit do hm hp nguyn liu v kh tun hon mang vo l phn ng th t.

Q14 = GC. qP = 2021,98 x 215593,475 = 435925694,6 (kj/h)

Tnh Q64. Nhit mt mt ra mi trng bn ngoi. Q64 = 0,01 x(Q14 + Q 24) = 0,01x ( 435925694,6 + 21758115,48)

= 4576838,10 (kj/h)

Tnh Q54:Nhit tiu tn do phn ng reforming.Q54 = Gc.qP4 = 92,30 x183823,529 = 16966911,73 (kj/h).

Tnh Q34: nhit do sn phm v kh tun hon mang ra.Q34 = Q14 + Q24 - Q44 - Q54 - Q64

Q34 = 435925694,6 + 21758115,48 - 46599834,28 - 16966911,73

- 4576838,10 = 389540226 (kj/h)

Q34 = 215593,475 qtr4

qtr4 = 1806,83 (kj/h)


36/36



Bng44:Cn bng nhit lng ca l phn ng th t.


Dng vo

Q14 803 215594,207 2021,98 435925694,6

Q24 803 21758115,48

Tng 457683810,00

Dng ra

Q34 763 215593,475 1806,83 389540226

Q44 763 46599834,28

Q54 763 16966911,73

Q64 763 4576838,10

Tng 457683810,00

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