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Shell Global Solutions

The Fluidized Catalytic Cracking Process 65 years of inspiration for technology development Mart Nieskens

Presentation to KIVI - NIRIA October 4th 2007

Shell Global Solutions

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A 1990 presentation updated with a decade of developments

Im pl

Imp

ation ent

ro

em

ve

t n e m

Design

R&

ion

Subject of this presentation

ra t

D Tro / g ubleshootin Inspection

e Op

Shell Global Solutions

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SIMPLIFIED REFINERY FLOW SCHEME HYDROSKIMMER

LPG Naphtha Crude

Crude Distilling Unit

Hydro Treater

Platformer Hydro Desulph. Unit

Kero/Gasoil

Long Residue (LR)

High Vacuum Unit

Flashed Distillate

LPG Mogas Kero Gasoil Fuel Oil

-

Cat Cracker

Hydro Desulph. Unit

Gasoil

COMPLEX

Short Residue (SR) Shell Global Solutions

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

Shell Global Solutions

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FLUID CAT. CRACKING UNIT (FCCU) Temp., C

Pres., barg

P Flue gas Reactor

2.0

T P

Light cycle oil

525

2.0

Heavy cycle oil

L 700

Steam Riser

350 Fractionator

Air blower

Slurry oil

Flashed Distillate / Long residue

Air Shell Global Solutions

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FCC Process

2-stage cyclone systems keep catalyst inside unit

Hydrocarbon/steam vapour to Main Fractionator & work-up

Inter & Intra-stitial hydrocarbons stripped from catalyst using steam Spent catalyst flows to regenerator and reactivated by burning off coke

Catalyst gradually deactivated by formation of coke on surface

Fresh Feed & Recycles contacted with regenerated catalyst in riser

Regenerated catalyst flows to bottom of liftpot-riser Catalyst flow controlled by pressure-balance and slide-valves

Shell Global Solutions

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FCC OPERATING CONDITIONS

Typ.

Feedrate, t/d

5000

Feed temperature, °C

250

Riser temperature, °C

525

Catalyst Circulation Rate (CCR), t/min

25

Catalyst to Oil (C/O) ratio, t/t Air-rate, t/d

7.5 3750

Regenerator temperature, °C

700

Coke burnt, t/d

250

Design Feed rate varies from 1.500 to 20.000 t/d

Typical….

FCC PRODUCT YIELDS

Typical range

Dry gas LPG Gasoline LCO

2-5 8 - 18 (C5 - 221 °C TBP) (221 - 370 °C TBP)

HCO + SO (370 +

°C TBP)

Coke

40 - 55 14 - 25 6 - 15 4-8

Shell Global Solutions

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FCC CATALYSTS

Particle size ~ 70 micron Particle density 1500 kg/m3 800 600

Real

ρ

app

400

REQUIREMENTS: •

Activity, selectivity and stability

•

Good fluidisation characteristics

•

200

Carrier of heat from regenerator to riser

Umb

Umf 0.01

0.1

vg = ∆v [cm/s] 1

10

Shell Global Solutions

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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 Shell Global Solutions

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Shell Support to the FCC Customers 1990 • SIPM Den Haag -

• •

(Shell International Petroleum Maatschappij)

Shell Oil Houston KSLA -

(Kon. Shell Lab. Amsterdam)

2007 • Shell Global Solutions -

Den Haag Amsterdam Houston Kuala Lumpur Bangalore

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

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Shell Global Solutions Shell Advised Fluid Catalytic Crackers Cat Cracking Services 1990 2007 •

30 units, being - Shell owned or - alliances

•

MONGSTAD DEER PARK MARTINEZ NORCO CONVENT PUGET SOUND PORT ARTHUR

SARNIA MONTREAL EAST

PERNIS

STANLOW Coryton

BERRE REICHSTETT PETIT COURONNE

43 units, being - Shell Owned or - Joint ventures, or - Third Party

HARBURG Miro RELIANCE

YOKKAICHI SEIBU TOA GEELONG CLYDE

Tupras

Petrotrin ECOPETROL

CARDON

BUENOS AIRES

DURBAN

PORT DICKSON

SRIRACHA

SINGAPORE

FCC Business Size World = 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) Shell Global Solutions

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Word-wide cat cracking capacity by Oil Company Total FCC, KB/D Residue FCC, KB/D ExxonMobil RD Shell Sinopec Valero BP Petrobras Total World Shell GS advise

1260 1080 740 730 670 520 430

140 510 170 50 50 80 75

16000 1900 12 %

1750 510 30%

Residue FCC: > 25% residue content

Our challenge is to process residue in a profitable and reliable way Shell Global Solutions

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Development in Shell Cat Cracker Design till 1990

The original…. Big inventory , high C/O Poorish cat., Much coke Lowish temp’s CCR 4 yrs reliable operation Full riser coverage Process benefits Low steam usage

Yield Shifts

(%wt on feed)

Dry Gas

- 0.3

LPG

- 0.5

Gasoline (C5-176°C)

+ 0.7

LCO

+ 0.1

Coke

Shell Global Solutions

constant

Example of process benefits

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Reactor Riser Internals

Shell proprietary riser internals prevent the natural segregation of catalyst from vapour Benefits:
Reliable; does not erode away
Gasoline yield > + 0.5 %wof
No extra pressure-drop
Minimized coking

Shell Global Solutions

Again, result of large size experimentation in Amsterdam

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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 Shell Global Solutions

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Minimising Coke Growth and Erosion in Cyclones

Coke growths on lee-side gas-outlet pipe Erosion “holes-through” at inlet and bottom 1. 2.

Better design of cyclone top Add Shell Bottom Internals Shell Global Solutions

Phenomena studied in Dutch University and in Amsterdam

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Shell FCC Cyclones System 1. Reliable Connections 2. Optimised I/O geometry

3. Internals to stop erosion and increase efficiency

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

4. Reliable Diplegs

Shell Global Solutions

Cyclone Service life exceeds 20 years

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Port Dickson RFCC – Unit Reliability Port Dickson Mech. Availability, % 1999-2002 average 2002-2005 average 1999-2005 average Solomon (2004) Asia-Pacific

99.4 94.4 96.9 94.6

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

2003 : -

•

2004 -

•

coking in the slurry recycle loop, due to 2002 T/A maintenance errors that mayways of individual trays in main fractionation were left open 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 Shell Global Solutions

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FCC “Performance Pyramid” Shell Global Solutions experience in all areas of the FCC performance pyramid: Catalyst

1.

Reliable design

2.

Unit operation (incl. SU & SD)

3.

Feed characterization

4.

Catalyst selection

Feed

Operation

Design

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Shell Global Solutions

Mechanical availability of Shell GS Cat Crackers 1% = $ 60 mln per year

Causes of Unscheduled Downtime Dow ntim e Days / Events (in %) per category

1) 2) 3) 4) 5) 6) 7) 8) 9)

Hardware, R&R Hardware, other Equipm ent Coking O ther Process Conditions Hum an Error Instrum entation and Safeguarding Utilities Scheduling/M argin O utside FCC Com plex

Shell Global Solutions

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Shell CCUs process high Resid feedstocks

2007: CCR optimal at ~6 max.

Shell Global Solutions

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Catalyst Selection • Objective: catalyst cost reduction + margin optimisation • 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

Unique pilot plant capabilities

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Catalyst Selection (continued) •

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 Shell Global Solutions

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SHARC – Shell FCC Process Model • 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

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Benefit from SHARC Applications

Economic Benefit Catalyst Selection Example Results–of NORCO Catalyst Selection Before Base Catalyst May-Oct., 1999 Relative Margin Relative Feed Rate Change Catalyst Addition CCR Basic Nitrogen C2<r (incl. H2S) C3= C4= Total LPG Naphtha (C5-221°C) LCO (221-355°C) HCO (355°C+) Coke 221°C Conversion Riser temperature FCC Naptha RON Clear FCC Naptha MON Clear E-Cat Activity (Grace) E-Cat Re2O3 (Grace)

$K/day % tons/day %wt ppm %wt %wt %wt %wt %wt %wt %wt %wt %wt °C

MAT %

100.0 9.1 0.26 192.3 4.39 5.35 6.34 17.4 45.44 15.86 11.06 5.85 73.08 533 93.65 81.53 67.92 0.56

SHARC Predictions New Catalyst

After New Catalyst Feb-Jul, 2000

14.2 97.9 5.9 0.26 192.3 4.51 5.28 6.24 17.4 46.95 15.19 10.03 5.92 74.78 539 93.95 82.03 Shell Global Solutions 68.0 1.03

16.7 99.2 6.4 0.24 228.4 4.60 5.28 6.44 17.26 46.93 15.96 9.59 5.66 74.45 535 94.1 82.2 68.1 1.03

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Resid processing E-cat poisoning with Vanadium Catalyst Vanadium resistance

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

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

63 62

E-cat activity

• Vanadium = poison for E-cat zeolite

Improved catalyst Vanadium resistance

61 60 59 58 57 56

Catalyst A

55

Catalyst B

54 5500

6000

6500

7000

7500

8000

E-cat Vanadium, ppmw

Shell Global Solutions

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Resid processing E-cat poisoning with Nickel Catalyst Nickel resistance

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

Improved catalyst Nickel resistance 0.40

• Nickel reacts hydrocarbons to H2+coke H2, wt%

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

0.35 0.30 0.25 0.20 0.15 4000

Catalyst B Catalyst A 4500

5000

5500

6000

Ni+V/4, ppm

Shell Global Solutions

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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)

Shell Global Solutions

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Additives reduce CCU emissions - SOx

H2 S release

SOx absorption

Shell Global Solutions

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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

14.0 SOx reduction, %

80%

11.2

R950 in INV, %

60%

8.4

40%

5.6

20%

2.8

0%

0.0

-20%

R950 in INV, %

SOx reduction, %

100%

-2.8 Nov’06

Jan’07

Shell Global Solutions

May’07

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Effectiveness of Gasoline Sulfur reducing additive - Target < 10 ppm Gasoline Sulfur achieved with feed HT and Additive 3.0%

Base 2.8%

Gasoline Sulfur/Feed Sulfur (%)

Additive 2.6% 2.4% 2.2% 2.0% 1.8%

Additive reduced gasoline Sulfur up to 40% at Constant Gasoline Cut Point

1.6% 1.4% 1.2% 1.0% 410

415

420

425

430

435

440

445

450

455

460

SIMDIST Gasoline T95 (°F) Shell Global Solutions

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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

Shell Global Solutions

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Process Design Modifications towards maximized flexibility 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

New Enabler: -

Equipment addition to conventional FCCU to ‘cleverly’ re-inject gasolinefractions aiming at superior diesel / propylene yields

Technology is ongoing R&D in Shell Lab’s Shell Global Solutions

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Catalyst Circulation Enhancement Technology Additions to Standpipe inlet • • •

• •

Unrivalled, recent concept Ensures standpipe-stability Enables much enhanced circulation rate (15-50% increase) Even with poor E-Cat 10 designs, 5 installed

Shell Global Solutions

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

1. The Flue Gas Cleaning System Shell Global Solutions

2. The Shell Third Stage Separator

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Evolution of Shell Third-Stage Separator

1960s-1980s Expander protection

1990s Tightening Emission Legislation

2005 Meeting