Detailed Hydrocarbon Analyses of Naphtha by On-Line NMR€¦ · Process NMR Associates Detailed Hydrocarbon Analyses of Naphtha by On-Line NMR Integration of Real-Time NMR Feed Analysis

Process NMR Associates

Detailed Hydrocarbon Analyses of Naphthaby On-Line NMR

Integration of Real-Time NMR Feed AnalysisWith Advanced Process Control and Optimization

Presented ByJohn Edwards, Ph.D.

Process NMR Associates, LLCDanbury, Connecticut

November 21, 2002Eastern Analytical Symposium, Somerset, New Jersey


Presentation Overview

• Process NMR Associates, LLC – Business Profile

• NMR Basics – Very Briefly

• Advantages/Disadvantages of NMR as a Process Spectroscopy

• Applications

1. Naphtha Steam Cracking Control and Optimization

2. Reformer Unit Control

• Conclusion


Company: Process NMR Associates, LLC

Founded : 1997

Personnel: 2 Ph.D. Chemists

Background: Analytical and Process Spectroscopy in Petroleum and Petrochemical (Texaco Inc.)

Facilities: 2 Invensys 58 MHz Process MRA Units300 MHz NMR (Liquids)200 MHz NMR (Solids)

Business: Application Development for Invensys Process MRAAnalytical NMR Services for Commercial and AcademicCustomers




NMR Innovations Developed to Bring NMR On-Line

• Permanent Magnet Stability and Design

• Shimming Protocols

• Flow-Through Probe Technology

• Post Processing Developments

Robust auto-phasing routines

Frequency Domain Averaging

Post-processing monitoring of each constituent spectrumfor heavy stream analyses where sediment/rust may be present.


Advantages and Disadvantages of NMR Applied to ProcessAdvantages:Non-optical spectroscopyNo spectral temperature dependence under optimal conditionsMinimal sampling requirementsSpectral response to sample chemistry is linearChemical regions of NMR spectra are orthogonalEntire volume is sampled by the NMR experimentWater is in distinct region and can be digitally removedDetailed hydrocarbon information is readily observed.Fundamental chemical information can be derived directly from spectrum.Colored or black samples are readily observed

Disadvantages:Solids cannot be observedIndividual molecular components not observed directly in the spectrum.Low sensitivity to impurities – quantitative > 1000 ppm.Sensitive to ferro-magnetics.Sample viscosity causes resolution changesNon-hydrogen containing species are not observed


H-Types Observed in a Gasoline 1H NMR Spectrum

8 7 6 5 4 3 2 1 0

CH

RR

HH

R

H

R

H

R

H

HR

CH2CH3

CH3

CH3

PPMOxygenate

H-Types Observed in a Gasoline 1H NMR Spectrum

8 7 6 5 4 3 2 1 0

CH

RR

HH

R

H

R

H

R

H

HR

CH2CH3

CH3

CH3

PPMOxygenate

8 7 6 5 4 3 2 1 0

CH

RR

HH

RR

HH

R

H

R

H

R

H

HR

R

H

R

H

R

H

HR

R

H

HR

CH2CH3

CH3CH3

CH3

PPMOxygenate


H2O


Application: Steam Cracking Optimization

Cracker Facility Capacity: 600,000 Tonnes per Year

Control Strategy: Feed Forward Detailed Hydrocarbon Analysis to SPYROOptimization Package (Technip/KTI) and APC

NMR Analysis: 3-4 Minute Cycle (Single Stream)16 Minute Cycle (4 Feed Streams)

NMR PLS Outputs: Naphtha – Detailed PIONAc4-c10 n-paraffin, c4-C11 i-paraffin, c6-c10 aromatics, c5-c10naphthenes

Other Projects require D86 and D2887 Distillation and Density

Value Added: Unit Optimization - $150K /year 4 Units Now Being Optimized ($600K/year)ROI 6-8 Months

Performance : NMR Available 99%+ Since May 2000Models Updated in a Limited Manner

Plant Issues :

Crackers produce 600,000 tonnes of ethylene per year

365 Days of Production per year with turnaround every third year

Strategic Requirements : Naphtha purchased with widely varying feed specification

Need:

Cracker Feed Characterization for APC and Optimization

APC Requirements: Monitor feed characteristics to minimize lost production due to high number of feed transitions:

Simplistically: 1) Heavier naphtha can violate coil outlet temperatures leading to coking or tube wall damage

2) Lighter naphtha can exceed downstream compressor loading

Optimization Requirements: Detailed PIONA analysis allows conditions to be optimized for optimum ethylene/propylene/butyleneproduction based on market conditions.



Distillate

Furnace

Steam

Separation

C2-C3Fractionator

C4+Fractionator

Light Gas Oils

Naphtha

NMR

Optimizer

APC

Steam Ratio

Feed FlowRate

CoilOutlet Temp

Economic Data : Feed/Product Values

PossibleNMR

Steam Cracking Process

EquistarBASF-Antwerpen

Petrochina

Ethylene

Propylene

Butylene

LN

MN-HN

BASF-Ludwigshaven


38.1937.4633.26Total iso-Paraffin

0.0500.2iso-C11

0.650.11.47iso-C10

1.840.52.45iso-C9

3.602.154.03iso-C8

7.105.335.8iso-C7

13.4813.499.05iso-C6

11.0515.519.86iso-C5

0.420.380.4iso-C4

37.7739.0833.08Total n-Paraffin

0.140.020.46n-C10

1.000.191.7n-C9

2.030.952.9n-C8

4.443.494.7n-C7

10.9210.57.97n-C6

15.9619.3711.73n-C5

3.284.533.46n-C4

Naphtha C

Naphtha B

Naphtha AComponent

0.030.120.3Total Olefins

5.503.3210Total Aromatics

0.0400.11Arom-C10

0.360.041.07Arom-C9

1.330.622.87Xylenes

0.210.070.55Ethyl-Benzene

1.791.233.15Toluene

1.771.362.25Benzene

18.3820.0223.36Total Naphthenes

0.0200.04Nap-C10

1.730.612.92Nap-C9

2.341.823.44Nap-C8

2.783.363.26Other Nap-C7

3.233.064.98Methylcyclohexane

3.133.823.77Cyclohexane

4.015.153.82Methylcyclopentane

1.142.21.13Cyclopentane

Naphtha C

Naphtha B

Naphtha AComponent

TYPICAL NAPHTHA


Naphtha 1 Naphtha 2 Naphtha 3Conversion (%) 81.5 94.2 92.0Outlet Temperature (K) 1053 1073 1073Steam/Feed Ratio 0.5 0.5 0.75

Yields (Wt%)Hydrogen 0.5 0.7 0.7Methane 12.0 15.3 14.2

Ethyne 0.1 0.3 0.3Ethene 19.5 23.5 24.0Ethane 4.0 4.0 3.4

Propene 16.2 16.2 15.5Propane 0.5 0.5 0.5

Butadiene 3.7 4.0 4.3Butenes 7.9 5.4 6.0Butane 2.6 1.4 1.7

C5+ 30.2 26.0 25.8

Fuel Oil 2.5 3.4 3.0

Cracking Process Products


N-Paraffin Variation Over 6 Months

20

25

30

35

40

45

50

55

1 7 13 19 25 31 37 43 49 55 61 67 73 79 85 91 97Naptha Purchase

Tota

l N-P

araf

fin (W

t%)


0

10000

20000

30000

40000

50000

60000

6000 6500 7000 7500 8000

0

10000

20000

30000

40000

50000

60000

6000 6500 7000 7500 8000

Arbitrary / Arbitrary Paged Y-Zoom CURSOR

File # 1 = TEST200002 11/14/2002 6:48 AM Res=None

Foxboro NMR SPC File.

Benzene

Cyclohexane


0

5

10

15

30 40 50 60 70 80 90 100 110

0

5

10

15

30 40 50 60 70 80 90 100 110

Aromatics Alpha-Protons

CH3

CH2

Cyclics

Olefins


0

.2

.4

.6

.8

1

1.2

1.4

38 40 42 44 46 48 50 52

0

.2

.4

.6

.8

1

1.2

1.4

38 40 42 44 46 48 50 52

Aromatic Region


0

5

10

15

85 90 95 100 105 110 115

0

5

10

15

85 90 95 100 105 110 115

Aliphatic Region


Steam Cracker Optimization - Project Timeline

Feasibility Performed (30 Samples) – December 1999

Further Off-Line Model Expansion (90 Samples) – December 1999-March 2000

Online System Installed – April 2000

On-Line Localization and Further Model Expansion (65 Samples)– May to July 2000

Validation Period – 1 Month 100% Availability Within Specified Accuracy Limit - Aug 2000

System Validated and Accepted – September 2000

Add Validation Period Samples to Models – (Models now contain 215 Samples)

NMR Put on Control (Detailed PIONA into SPYRO Model for Unit Optimization) Oct 2000

Models have been performing relatively untouched (6 parameters of 32 updated on 4 occasions) since end of validation period. Models updated in limited manner 5 times in 2 years.

99+% Availability September 2000 – May 2002

March 2002 – Three Further Feed-Streams Added to NMR – No model updates required.


Toluene

Actual Toluene (Wt%)

Pred

icte

d To

luen

e (W

t%) (

F9

C1

)

1

1

23

45

6

7

8

9

10

11

12

1314

15

16

17

18

1920

21

22

2325

26

2728

2930

31

32

33

34

35

36

37

383940

4142

43

44

45

46

4950

51

53

5456

58

59

6263

66

68

69

70

71

73

75

76

77

78

79

80

82

83

84

85

86

87

88

90

91

929394

95

9697

98

99

101

102

103

104

105

106

108

109

110

111

112

113

114

115

116

117

118119120

121

122123

124

125126

127128

129130131132133134135136137

138139140141142143

144145146

147148149

150151152

156157158159160161

162163164

165166167168169170

171172173174175176

177178179180181182183184185186187188

189190191

192193194195196197198199200

201202203

204205206

207208209210211212

213214215

216217218219220221222223224

225226227 228229230

231232233

234235236

237238239240241242243244245246247248249250251252253254

255256257258259260261262263

264265266

267268269270271272273274275

279280281282

283284285

286287288

289290291

292293294

295296297298299300301302303

304305306

307308309

310311312313314315

319320321

322323324325326327

328329330

331332333334335336

337338339

340341342343344345

346347348349350351

352353354

355356357358359360

361362363364365366367368369

370371372

373374375

376377378379380381382383384

385386387

388389390391392393

394395396397398399400401402

403404405

406407408

409410411

412413414

427428429 430431432433434435

436437438

439440441

445446447

448449450

451452453454455456

457458459

460461462

463464

465466467

471472473

477478

481482

483484485489490493494495496

-.5

1

2.5

4

5.5

0 1.5 3 4.5

Spectral Units ( )Be

ta C

oeffi

cien

t ( F

9 C

1 )

-1.5

0

1.5

10 40 70 100 130

-1.5

0

1.5

10 40 70 100 130


Cyclohexane

Beta Coefficients

Spectral Units ( )Spectral Units ( )

Beta

Coe

ffici

ent (

F9

C1

)

-2

-.5

1

2.5

10 40 70 100 130

-2

-.5

1

2.5

10 40 70 100 130

Pred

icte

d C

yclo

hexa

ne( F

9 C

1 )

1

4

7

10

1 4 7 10 1 4 7 10

1

2345

6

78

910

11

12

1314

15

16

17

18

19

2021

22

23

242526

2728

29

30

3132

33

34

35

36

37

3839

4041

42

4346

47

48

49

50

51

52

53

54

55

56

58

596067

68

69

7071

72

73

74

75

76

77

7879

80

81

82

8485

8687

88

89

91

92

93

9495

96

97

98

99

100

101

102103

104

105

106

108109

110111

112

113

115116

117118

119120121

122123124125126127

128129130131132133

134135136

137138139

140141142

143144145146147148149150151152153154

161162163164165166

167168169170171172173174175176177178

179180181182183184

185186187

191192193194195196

197198199

200201202

203204205

206207208

209210211

212213214

215216217

218219220

221222223

224225226

227228229230231232

233234235

236237238239240241

243244

245246247248249250251

252253

254255256

257258259

260261262

263264265

266267268

269270271272

273274275

276277278

279280281

282283284

285286287288289290

291292293294295296

297298299

300301302

303304305

309310311

312313314

315316317

318319320

321322323

324325326

327328329

330331332333334335

336337338339340341

342343

345346347348349350

351352353354355356357358359

360361362

363364365

366367368

369370371372373374375376377

378379380381382383

384385386

387388389390391392

393394395396397398399400401

402403404

405406407408409410

414415416417418419

420421422423424425429430431432433434438439440441442443

444445446447448449

453454455

456457

458459460464465466

482483484485486487488489

1

4

7

10

1 4 7 10

Actual Cyclohexane (Wt%)


Actual Normal-C5

Pred

icte

d n-

C5

( F10

C1

)

4 10 16 22 4 10 16 22

12345

6

7

8

911

12

13

14

15

1617

18

19

20

21

22

23

24

2526

27

28

29

30

3132

333435

36

3738394041

42

44

45

4647

48

49

50

51

525354

55

56

62

63

64

65

67

68

70

72

73

74

75

76

77

78

79

80

81

82

84

85

87

89

90

91

92

93

94

95

96

97

98

99

100101

102103104

105106107108109110

111112113114115116

117118119120121122

123124125

126127128129130131

132133134

138139140

144145146

147148

149

150153

154155

156157158

159160161162163164

168169170

171172173

174175176177178179

180181182

183184185

186187188

189190191

192193194195196197

198199200

201202203

204205207208209210211

212213214215216217218

219220221

222223224225226227228229230

231232233

234235236

237238239240241242

243244245

246

247

248249

250251252

253254255

256257258

259260261

262263264265266267

268269270274275276

277278279

280281282

283284285286287288

289290291

295296297

298299300

301302303

304305306307308309

310311312

313314315

316317318

319320321322

323324325326327

328329330

337338339

343344345

346347348349350351

352353354

355356357358359360

361362363364365366367368369370371372

373374375376377378

379380381

382383384

385386387

388389390391392393

394395396

397398399

406407408

409410411

412413414

415416417

418419

423424425429430431

432433434435436

437438444445446

447448

449450451452453454

4

10

16

22

4 10 16 22 Spectral Units ( )Spectral Units ( )

Beta

Coe

ffici

ent (

F10

C1

)Be

ta C

oeffi

cien

t ( F

10 C

1 )

-8

-2

4

10

10 40 70 100 130

-8

-2

4

10

10 40 70 100 130

Normal-C5


96 Hours of NMR Process Output - PINA

0

5

10

15

20

25

30

35

40

45

1 173 345 517 689 861 1033 1205 1377 1549 1721

Total n-ParaffinTotal iso-ParaffinTotal NaphthenesTotal Aromatics


96 Hours of NMR Process Output – n-Paraffin Components

0

2

4

6

8

10

12

14

16

18

1 143 285 427 569 711 853 995 1137 1279 1421 1563 1705

n-C5n-C6n-C7n-C8


0

2

4

6

8

10

12

14

16

1 147 293 439 585 731 877 1023 1169 1315 1461 1607 1753

iso-C5iso-C6iso-C7iso-C8iso-C9

96 Hours of NMR Process Output – iso-Paraffin Components


0

1

2

3

4

5

6

1 177 353 529 705 881 1057 1233 1409 1585

MethylcyclopentaneCyclohexaneMethylcyclohexaneOther Nap-C7Nap-C8Nap-C9

96 Hours of NMR Process Output – Naphthene Components


0

0.5

1

1.5

2

2.5

3

3.5

4

1 167 333 499 665 831 997 1163 1329 1495 1661

BenzeneTolueneEthyl-BenzeneXylenes

96 Hours of NMR Process Output – Aromatic Components




Cyclopentane

5/17

5/24

5/31 6/7 6/14

6/21

6/28 7/5 7/12

7/19

7/26 8/2 8/9 8/16

8/23

8/30 9/6

Date

Wt% GC

NMR



Parameter R Std Dev Mean Devn-c4 0.9340 0.52 0.067n-c5 0.9761 0.73 -0.004n-c6 0.9616 0.73 -0.093n-c7 0.9840 0.33 -0.032n-c8 0.9882 0.29 -0.008n-c9 0.9918 0.18 -0.003n-c10 0.9716 0.13 0.022Total n-paraffin 0.9840 0.81 0.013I-c4 0.8765 0.07 0.001I-c5 0.9834 0.76 0.043i-C6 0.9865 0.59 -0.050i-C7 0.9119 0.46 -0.015i-C8 0.9800 0.42 -0.035i-C9 0.9905 0.26 0.010i-C10 0.9866 0.24 0.013i-C11 0.9613 0.08 -0.007Total I-paraffin 0.9617 0.81 -0.011cyclopentane 0.9821 0.14 -0.004me-cyclopentane 0.9937 0.23 -0.018Cyclohexane 0.9940 0.26 0.034Methylcyclohexane 0.9872 0.29 0.001Other C7-Nap 0.9025 0.32 -0.052c8-Nap 0.9713 0.36 0.002c9-Nap 0.9892 0.28 0.026c10-Nap 0.8950 0.06 -0.001Total Naphthenes 0.9794 0.83 0.019Benzene 0.9950 0.10 0.006Toluene 0.9920 0.17 0.007Ethylbenzene 0.9902 0.04 0.002Xylenes 0.9951 0.14 0.003C9 - Arom 0.9875 0.16 0.006C10-arom 0.9586 0.07 0.001Total Aromatics 0.9967 0.31 0.022

Single PLS Model for Each GC Component

Low Model Maintenance

SPYRO Optimization and APC Utilize Real Time Analysis

4 Crackers Now Covered by 1 NMR

Multiple (12) GC Analyzers Replaced Yielding Reduced Maintenance

Reduced Laboratory Requirements

Other Installations:Expanding Model Base to Cover Gas Oils andMixed Naphtha/Gas Oil Blend OperationModel base to be developed for NMR analyzer on gaseous products of naphtha cracker.


Conclusion

High Resolution FT-NMR has Left the Research

Laboratory…. and is Arriving in a Process Near You!

See Further Information at http://www.process-nmr.com


Acknowledgements

Paul Giammatteo – PNA

Tal Cohen – Foxboro NMR Israel

Tony Van Poyenbroeck – Cardoen Technology, Belgium

Invensys

Our NMR Customers

Detailed Hydrocarbon Analyses of Naphtha by On-Line NMR€¦ · Process NMR Associates Detailed Hydrocarbon Analyses of Naphtha by On-Line NMR Integration of Real-Time NMR Feed Analysis

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