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Shell Global Solutions

The Fluidized Catalytic Cracking ProcessThe Fluidized Catalytic Cracking Process65 years of inspiration for technology development65 years of inspiration for technology development

Mart Nieskens

Presentation to KIVI - NIRIA October 4th 2007

2Shell Global Solutions

A 1990 presentation updated with a decade of developments

3Shell Global SolutionsInspection

Troubleshooting/

Design

Implemen

tatio

n

Operatio

nR&

D

Impro

ve

ment

Subject of thispresentation

4Shell Global Solutions

SIMPLIFIED REFINERY FLOW SCHEME

Platformer

HydroDesulph.

Unit

HydroTreater

LPGMogas

KeroGasoil

Fuel Oil

CrudeDistilling

Unit

HYDROSKIMMER

Long Residue (LR)

Naphtha

Crude

LPG

Kero/Gasoil

COMPLEX

HighVacuum

Unit

-

FlashedDistillate

Short Residue (SR)

Gasoil

HydroDesulph.

UnitCatCat CrackerCracker

5Shell Global Solutions

Residue Upgrade (>370 oC) in relation to FCC process ability

6Shell Global Solutions

FLUID CAT. CRACKING UNIT (FCCU)

Flue gas

Air

Air blower

Riser

Fractionator

Flashed Distillate /Long residue

Light cycle oil

Heavy cycle oil

Slurry oil

Steam

Reactor

L

T

P

P

700

525

350

2.0

2.0

Temp., CPres., barg

7Shell Global Solutions

FCC Process

Fresh Feed & Recycles contacted with regenerated catalyst in riser

Catalyst gradually deactivated by formation of coke on surface

Hydrocarbon/steam vapour to Main Fractionator & work-upHydrocarbon/steam vapour to Main Fractionator & work-up

Inter & Intra-stitial hydrocarbons stripped from catalyst using steam

Catalyst flow controlled by

pressure-balance and slide-valves

2-stage cyclone systems keep catalyst inside unit

Spent catalyst flows to regenerator and reactivated by burning off coke

Spent catalyst flows to regenerator and reactivated by burning off coke

Regenerated catalyst flows to bottom of liftpot-riser

Regenerated catalyst flows to bottom of liftpot-riser

8Shell Global Solutions

2 - 5

8 - 18

40 - 55

14 - 25

6 - 15

4 - 8

Dry gas

LPG

Gasoline (C5 - 221 °°°°C TBP)

LCO (221 - 370 °°°°C TBP)

HCO + SO (370 + °°°°C TBP)

Coke

Typical rangeFCC PRODUCT YIELDSFCC PRODUCT YIELDS

5000

250

525

25

7.5

3750

700

250

Feedrate, t/d

Feed temperature, °°°°C

Riser temperature, °°°°C

Catalyst Circulation Rate (CCR), t/min

Catalyst to Oil (C/O) ratio, t/t

Air-rate, t/d

Regenerator temperature, °°°°C

Coke burnt, t/d

Typ.FCC OPERATING FCC OPERATING CONDITIONSCONDITIONS Typical….

Design Feed rate varies from 1.500 to 20.000 t/d

9Shell Global Solutions

FCC CATALYSTS

0.01 0.1 1 10 100

200

400

600

800

Umf

Umb

Real

vg = ∆v [cm/s]

ρapp

REQUIREMENTS:

• Activity, selectivity and stability

• Good fluidisation characteristics

• Carrier of heat from regenerator to riser

Particle size ~ 70 micronParticle density 1500 kg/m3

10Shell Global Solutions

Fluid. Cat. Circulation Unit (“FCCU”)

Purposes• Circulates Catalyst from “A to B and back”

• Does so unattended, smoothly and reliably• Gives good P build-up at ‘any’ rate

Elements• gas and catalyst quality

• flow-phenomena, (non)-fluidisation• Separations : particles from gas; stripping; burning

• Slide Valve: control / safety

11Shell Global Solutions

Shell Support to the FCC Customers

19901990

•• SIPM Den HaagSIPM Den Haag-- (Shell International Petroleum (Shell International Petroleum

MaatschappijMaatschappij))

•• Shell Oil Houston Shell Oil Houston

•• KSLA KSLA -- ((KonKon. Shell Lab. Amsterdam). Shell Lab. Amsterdam)

20072007

•• Shell Global SolutionsShell Global Solutions-- Den HaagDen Haag

-- AmsterdamAmsterdam

-- Houston Houston

-- Kuala LumpurKuala Lumpur

-- BangaloreBangalore

Shell Global Solutions is Shell’s technological consultancy group for Up- & Downstream Facilities, with strong R&D capabilities.

Shell Global SolutionsCat Cracking Services

BUENOS AIRES DURBAN SINGAPORESRIRACHA

GEELONGCLYDE

YOKKAICHISEIBUTOA

STANLOWCoryton

PERNIS HARBURG

Miro

BERREREICHSTETT

PETIT COURONNE

CARDON

SARNIAMONTREAL EAST

DEER PARKMARTINEZ

NORCOCONVENT

PUGET SOUNDPORT ARTHUR

PORT

DICKSON

RELIANCE

MONGSTAD

ECOPETROL

Petrotrin

Tupras

Shell Advised Fluid Catalytic Crackers1990• 30 units, being

- Shell owned or - alliances

2007• 43 units, being

- Shell Owned or- Joint ventures, or- Third Party

13Shell Global Solutions

FCC Business SizeWorld = 16 million bbl/d

(46% in USA)Bigger than hydrocracking, coking and thermocracking capacities altogether

Shell = 1.0 MM bbl/d (> 53 MM tons/a in 23 FCC units: 6/2 US/Canada; 7/2 AsiaP/South; 6 EUR)

3rd party customers: 0.9 MM bbl/d(47 MM t/a)11 Kb/d to 200 Kb/d FCC units

Margin:@ 40 USD/t FCC > $ 2 bln/a@ 120 USD/t FCC > $ 6 bln/a (2006)

14Shell Global Solutions

Word-wide cat cracking capacity by Oil Company

Total FCC, KB/D Residue FCC, KB/D

ExxonMobil 1260 140RD Shell 1080 510Sinopec 740 170Valero 730 50BP 670 50Petrobras 520 80Total 430 75

World 16000 1750Shell GS advise 1900 510

12 % 30%

Residue FCC: > 25% residue contentOur challenge is to process residueOur challenge is to process residuein a profitable and reliable wayin a profitable and reliable way

15Shell Global Solutions

Development in Shell Cat Cracker Design till 1990

The original….Big inventory , high C/OPoorish cat., Much cokeLowish temp’s CCR<0.3CCR<0.3

Zeolite catalystRiser CrackingStripper-baffles inside reactor. CCR < 1.5CCR < 1.5Complete Combustion

Gasoline ++ / fuel ––Resid feed (CCR < 3CCR < 3)no reactor; feedgunsCat.coolers; high T’sStill single regen.vessel

Compact unit sizeTSS build into RegenInnovative designHigh cap. Cat.coolerCCR < 7CCR < 7

16Shell Global Solutions

Process and catalyst development have improved the conversion and yields

Late 1990’s: Late 1990’s: •• AluminaAlumina matrices for matrices for

Nickel Nickel passivationpassivation•• Metal traps for Metal traps for

Vanadium Vanadium passivationpassivation•• Improved Improved zeolite zeolite stability for stability for

maximum conversionmaximum conversion•• Improved catalyst porosity Improved catalyst porosity

for for residresid processingprocessing

2000’s : Additives2000’s : Additives•• ZSMZSM--5 for 5 for

octane improvement octane improvement light olefins (C3light olefins (C3==, C4, C4==))

•• SOSOxx,,, , NONOxx, , Gasoline Gasoline SulfurSulfur

17Shell Global Solutions

This is development ……

In 2000s

Dry Gas Down

LPG + Gasoline + LCO further optimized

All with more difficult feedstock

Improving Product Yields (while increasing residue in feed)

For a 5000 t/d unit, any 1 % conversion increase equates a gain of 1 million Euro per year gross margin

18Shell Global Solutions

The Geelong FCCU: World’s most compact RFCCU

• Fine Spray Feed Nozzles• Riser reaching reactor top• Compact Reactor Separation• Compact Stripper Packing• Catalyst Spreader in Regen.• Deleting one stage of

cyclones in regenerator• Low Energy•• Unit performed reliably and Unit performed reliably and

to spec’s only after tuning the to spec’s only after tuning the equipment elementsequipment elements

19Shell Global Solutions

The path towards the current Shell Design RFCCU

Started from the innovative design in Geelong RFCCU

Reliability Revamp options brought into the Singapore RFCCU

New standard set with the Port Dickson RFCCU (Malaysia)

20Shell Global Solutions

Port Dickson RFCC Unit (1999)

• Feed rate ~ 42,000 BPD;

• ConCarbon ~ 5.0 average, 6.2 max

21Shell Global Solutions

Port Dickson RFCC – Project Execution and Operation

• 14 million man-hours without a lost time incident

• Project execution: on time, 10% under budget

• Total installed cost: $370 million (1999)

• Flawless Start-up:

set new FCC/RFCC record of on spec products 48 hours after feed in (old record 72 hours)

• Best grassroots RFCC:

set new record of on stream factor of 99.4% for the first run (1999 – 2002). The 3-year run-length is mandated

22Shell Global Solutions

Port Dickson RFCC – Unit Operation and Performance

• Unit objective – Max. gasoline and propylene

• Crude - 52.5 %w Oman and 47.5 %w Bach Ho

• Feed - LR API 23.9, ~ 5.0 concarbon

• Catalyst – CCIC ~ 7 ton/day, 2% ZSM-5, Ni ~4700 ppm, V ~ 4000 ppm

• Unit yields –

70 wt% conversion (4.8% dry gas, 17.2 % LPG, 50.7 % gasoline),

11.3 wt % LCO, 8.6 % HCO/Slurry, 7. 4 % coke

• 0.05 to 0.1 wt% ash in slurry (by-pass hydroclone)

• Partial burn regenerator with COB

• Cat loss from flue gas < 0.5 ton/day (< 50mg/nM3)

23Shell Global Solutions

Shell High Performance Feed NozzlesFeed Nozzle Configuration Side View of Nozzle Arrangement

Full size tested in AmsterdamProven reliability in severe conditions

D ~ 1.5 mD ~ 1.5 m

24Shell Global Solutions

Shell High Performance Feed Nozzles

Yield Shifts (%wt on feed)

Dry Gas - 0.3

LPG - 0.5

Gasoline (C5Gasoline (C5--176176°°C)C) + 0.7+ 0.7

LCO + 0.1

Coke constant

Example of process benefits

1. > 4 yrs reliable operation2. Full riser coverage3. Process benefits4. Low steam usage

25Shell Global Solutions

Reactor Riser Internals

Shell proprietary riser internals prevent the natural segregation of catalyst fromvapour

Benefits:

� Reliable; does not erode away

� Gasoline yield > + 0.5 %wof

� No extra pressure-drop

� Minimized coking

Again, result of large size experimentation in Amsterdam

26Shell Global Solutions

Adding Reliable Internals for Improved Stripping

Packing enhances the hydrocarbon recovery from catalyst surface by counter flow of steam up and catalyst down.

Closely structured packing has questionable reliability due to plugging, particularly for RFCC operation

PentaFlow Packing is an improved design balancing high performance, high reliability and easy maintenance

27Shell Global Solutions

Minimising Coke Growth and Erosion in Cyclones

Coke growths on lee-side gas-outlet pipeErosion “holes-through” at inlet and bottom

1. Better design of cyclone top2. Add Shell Bottom Internals

Phenomena studied in Dutch University and in Amsterdam

28Shell Global Solutions

10-fold improvement in reliability in last decade; steady since

Shell FCC Cyclones System1. Reliable Connections

2. Optimised I/O geometry

3. Internals to stop erosion and increase efficiency

4. Reliable Diplegs

Cyclone Service life exceeds 20 years

29Shell Global Solutions

Port Dickson RFCC – Unit Reliability

Port Dickson Mech. Availability, %1999-2002 average 99.42002-2005 average 94.41999-2005 average 96.9Solomon (2004) Asia-Pacific 94.6

Major issues and learning (2002 –2005) – T/A errors unrelated to design :

• 2003 : - coking in the slurry recycle loop, due to 2002 T/A maintenance errors that

mayways of individual trays in main fractionation were left open

• 2004

- crack in regenerator overhead line due to an error in 2002 T/A that a repair was not carried out – resolved by adding an expansion joint

• 2005

• nationwide power failure

30Shell Global Solutions

FCC “Performance Pyramid”

Design

Feed

Operation

Catalyst1. Reliable design

2. Unit operation (incl. SU & SD)

3. Feed characterization

4. Catalyst selection

Shell Global Solutions experience in all areas of the FCC performance pyramid:

Shell Global Solutions

Mechanical availability of Shell GS Cat Crackers

1% = $ 60 mln per year

32Shell Global Solutions

Causes of Unscheduled Downtime

Downtime Days / Events (in %) per category

1) Hardware, R&R

2) Hardware, other Equipment

3) Coking

4) Other Process Conditions

5) Human Error

6) Instrumentation and Safeguarding

7) Utilities

8) Scheduling/Margin

9) Outside FCC Complex

33Shell Global Solutions

Shell CCUs process high Resid feedstocks

2007:CCR optimal at ~6 max.

34Shell Global Solutions

• Objective: catalyst cost reduction + marginoptimisation

• Testing properly aged catalysts in our pilot plant, using actual feedstock and process conditions tailored to your operation

• Translating pilot plant results to your commercial unit using the Shell FCC Process Model (SHARC)

• Ranking according to value added

• Independence from catalyst producers

Catalyst Selection

Unique pilot plant capabilities

35Shell Global Solutions

• Triggers for catalyst selection� Change in Refinery objectives (i.e. to make more octane, more propylene, lower gasoline olefins, etc.)

�Major FCC unit revamp (i.e. close coupled cyclones, etc.)� Change of feedstock to unit

� Availability of new catalyst technology

• 5-6 locations per year

• Benefits: ~$ 1.5 mln/yr per location

Catalyst Selection (continued)

36Shell Global Solutions

• Proprietary heat-balanced FCC process model developed by Shell

• Yield predictions are validated against commercial test run data.

• Integrated with FCC on-line optimization system and refinery planning and scheduling tools.

• Users of SHARC have seen their FCC profitability improve by an

annual margin increase of say USD 2-3 million

SHARC – Shell FCC Process Model

37Shell Global Solutions

Results of NORCO Catalyst SelectionEconomic Benefit – Catalyst Selection Example

Benefit from SHARC Applications

Before Base Catalyst

May-Oct., 1999

SHARC Predictions

New Catalyst

After New Catalyst

Feb-Jul, 2000

Relative Margin $K/day - 14.2 16.7 Relative Feed Rate Change % 100.0 97.9 99.2 Catalyst Addition tons/day 9.1 5.9 6.4 CCR %wt 0.26 0.26 0.24 Basic Nitrogen ppm 192.3 192.3 228.4 C2&ltr (incl. H2S) %wt 4.39 4.51 4.60 C3= %wt 5.35 5.28 5.28 C4= %wt 6.34 6.24 6.44 Total LPG %wt 17.4 17.4 17.26 Naphtha (C5-221°C) %wt 45.44 46.95 46.93 LCO (221-355°C) %wt 15.86 15.19 15.96 HCO (355°C+) %wt 11.06 10.03 9.59 Coke %wt 5.85 5.92 5.66 221°C Conversion %wt 73.08 74.78 74.45 Riser temperature °C 533 539 535 FCC Naptha RON Clear 93.65 93.95 94.1 FCC Naptha MON Clear 81.53 82.03 82.2 E-Cat Activity (Grace) MAT 67.92 68.0 68.1 E-Cat Re2O3 (Grace) % 0.56 1.03 1.03

38Shell Global Solutions

Improved catalyst Vanadium resistance

54

55

56

57

58

59

60

61

62

63

5500 6000 6500 7000 7500 8000

E-cat Vanadium, ppmw

E-c

at

ac

tiv

ity

Catalyst A

Catalyst B

Resid processing -E-cat poisoning with Vanadium

• Some Shell advised resid units operate in an excess of 7500 ppm Vanadium !

• Vanadium = poison for E-cat zeolite

• SGSi pilot plant catalyst selection procedure selects the most Vanadium resistant catalysts for the SGSi advised CCUs

Catalyst Vanadium resistance

39Shell Global Solutions

Improved catalyst Nickel resistance

0.15

0.20

0.25

0.30

0.35

0.40

4000 4500 5000 5500 6000

Ni+V/4, ppm

H2, w

t%Catalyst B

Catalyst A

Resid processing -E-cat poisoning with Nickel

• Some Shell advised resid units operate at very high E-cat Nickel levels

• Nickel reacts hydrocarbons to H2+coke

• SGSi catalyst selection methods test catalyst Nickel tolerance in realistic conditions in a pilot plant deactivation unit

Catalyst Nickel resistance

40Shell Global Solutions

Additives to adjust product slate or quality

ZSM-5 and gasoline-S reducers

• SGSi has pilot plant facilities to carry out dedicated pilot plant evaluations for ZSM-5 and Gasoline Sulfur reduction additives

• Several SGSi advised units use these additives continuously (ZSM-5)

41Shell Global Solutions

Additives reduce CCU emissions - SOx

SOx absorption

H2 S release

42Shell Global Solutions

Additives for CCU emissions – SOx and NOx

SGSi gives support for SOx and NOx additive selection and monitoring

Example: SOx additive trial at Reichstett – up to 85% SOx reduction

-20%

0%

20%

40%

60%

80%

100%

SO

x r

ed

ucti

on

, %

-2.8

0.0

2.8

5.6

8.4

11.2

14.0

R950 i

n I

NV

, %

SOx reduction, %

R950 in INV, %

Nov’06 Jan’07 May’07

43Shell Global Solutions

1.0%

1.2%

1.4%

1.6%

1.8%

2.0%

2.2%

2.4%

2.6%

2.8%

3.0%

410 415 420 425 430 435 440 445 450 455 460

SIMDIST Gasoline T95 (°F)

Gaso

lin

e S

ulf

ur/

Feed

Su

lfu

r (%

)

Base

Additive

Additive reduced gasoline Sulfur up to 40% at Constant Gasoline

Cut Point

Effectiveness of Gasoline Sulfur reducing additive- Target < 10 ppm Gasoline Sulfur achieved with feed HT and Additive

44Shell Global Solutions

Latest Shell Developments … Examples

• Process Design Modifications towards maximized flexibility in products like Diesel / Propylene

• Catalyst Circulation Enhancement for increased capacity

• Flue Gas Cleaning towards very low stack emissions

45Shell Global Solutions

Process Design Modifications towards maximized Process Design Modifications towards maximized flexibility in products like Diesel / Propyleneflexibility in products like Diesel / Propylene

Enablers:- In conventional FCCU tuning of operating conditions, like:

- “cat-to-oil ratio”

- Riser temperature- Sharpened design of feedguns, riser-internals, post-riser contact time

- Catalyst formulation and activity- Tuning of ZSM-5 catalyst-additive for propylene

Technology is ongoing R&D in Shell Lab’s

New Enabler:- Equipment addition to conventional FCCU to ‘cleverly’ re-inject gasoline-fractions aiming at superior diesel / propylene yields

46Shell Global Solutions

Catalyst Circulation Enhancement TechnologyCatalyst Circulation Enhancement Technology

Additions to Standpipe inlet

• Unrivalled, recent concept• Ensures standpipe-stability

• Enables much enhanced circulation rate

(15(15--50% increase)50% increase)

• Even with poor E-Cat

• 10 designs, 5 installed

47Shell Global Solutions

Third Stage Separator System (TSS)Third Stage Separator System (TSS)the reliable and costthe reliable and cost--effective solution to reach lowest emissionseffective solution to reach lowest emissions

1. The Flue Gas Cleaning System

2. The Shell Third Stage Separator

48Shell Global Solutions

Evolution of Shell Third-Stage Separator

1960s-1980s

Expander protection 1990s

Tightening Emission Legislation 2005

Meeting <50 mg/m3

49Shell Global Solutions

As we respect our neighbours, andTo keep our license to operate

This is development……

Improving Clean Stack (and reducing SOx/NOx emission)

50Shell Global Solutions

Closing Remarks

• Shell Global Solutions is for CatCracking a unique entity to provide 24 hr/day technological service to 12% of world’s FCC users.

• For Residue-FCC’s where reliability is most at stake, the leading position is even stronger.

• Despite increased heaviness and impurities in feed (S, N etc) Cat Cracking remains a worldwide leading conversion technology

• Main challenges for the RFCC process are: - Reliability of operation

- Quality of products and of environment- Meeting refiner’s need for wide flexibility on product-slate and feedstock

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