stratco_alkylationtechnologyimprovements

7/31/2019 STRATCO_AlkylationTechnologyImprovements

1/23

2007 Annual Meeting

STRATCO

Alkylation Technology

Improvements


2/23

2007 Annual Meeting

Areas of Improvement

Net Effluent / Depropanizer Feed TreatingReduce hydrocarbon inventory, improve

separation and treating

Reaction Zone

Reduce hydrocarbon and sulfuric acid

inventory, improve reliability, operability andalkylate product quality


3/23

2007 Annual Meeting

Net Effluent / DEP Feed

Treating Improvements

Static Mixers New process design includes static mixers in each

hydrocarbon treating step

Coalescing Media New process design includes media in all treating

vessels

Eliminates the electrostatic precipitator and largevessels needed for gravity settling

Previous design 30 minutes of residence time,

with coalescing media ~3 fold volume decrease


4/23

2007 Annual Meeting

Net Effluent Treating

NET EFFLUENT

ACID TO RXN.

FRESH

ACID

ACID WASH

COALESCER

L.P. STEAM

HOT

ALKYLATE

PRODUCT

SPENT ALKALINE

WATER TO BLOWDOWN

PROCESS

WATER

WATER WASHCOALESCER

ALKALINE

WATER WASH

DEISOBUTANIZER

FEED


5/23

2007 Annual Meeting

Depropanizer/Propane

Purge Treating

TO NET

EFFLUENTTREATING

FRESH

CAUSTIC

DEPROPANIZERFEED TO DEPROPANIZER/

BATTERY LIMITS

PROCESS

WATER

CAUSTIC

WASHWATER WASH

COALESCER


6/23

2007 Annual Meeting

Reaction Zone

Improvements

Acid Settlers

Contactor Reactor Repairs/Upgrades Tube Insert Technology

Tube Bundles


7/23

2007 Annual Meeting

Acid Settlers

Previous design: Internal H distributor, largevessels, 12 x 50 or 15 x 70

New Design: Coalescing media, smallervessels 8 x 32, 10 x 40, or 12 x 40

Volume decrease ~ 2.7 to 3.5 fold


8/23

2007 Annual Meeting

Contactor Reactor

Repairs/Upgrades

Hydraulic Head Repair

Feed Nozzles

Mechanical Seal Improvements

Metallurgy Upgrades (Impeller, Impeller Cap, WearRing, Shell Transition Cone, Spider Assembly, Hydraulic Head)


9/23

2007 Annual Meeting

Contactor ReactorA - Contactor Reactor ShellB - Tube Bundle AssemblyC - Hydraulic Head AssemblyD - Motor, Turbine/Driver

Coolant

In

Emulsion

To Settler

CoolantOut

CirculationTube A

CImpeller B

Acid

HC

DD

Feed NozzlesSpider


10/23

2007 Annual Meeting

Tube InsertsIssue:

Poor Distribution Effluent enters at

bottom

Partial PhaseSeparation in

Channel Inlet Non-Uniform

Distribution

Two-Phase Effluent

Refrigerant Inlet


11/23

2007 Annual Meeting

Indications and

Problems ofPoor Distribution

Lower than expected calculated overallheat transfer coefficient

Corrosion/Erosion of selective tubes dueto lack of cooling

Tubes may run dry and therefore no

vaporization to provide cooling

Result is reduction of overall available

surface area for heat transfer


12/23

2007 Annual Meeting

Opportunity for

Improvement

TO FEED/EFFLUENT

EXCHANGERS

OLEFIN AND

ISOBUTANE

SPENTACID

FRESH

ACID

PC

REFRIGERANTRECYCLE

TO REFRIGERATIONSECTION

FROM

REFRIGERATION

SECTION

ACID SETTLERS

MCONTACTORREACTORS Pressure Drop

Available Over

PCV

SUCTIONTRAP

FLASHDRUM


13/23

2007 Annual Meeting

Approach

Transfer pressure drop from PCV to tubesheet by use of tube inserts

Inlet to tubes is now single phaseproviding more uniform flow distribution

Flashing occurs over the tube inserts


14/23

2007 Annual Meeting

What Do They Look

Like?


15/23

2007 Annual Meeting


16/23

2007 Annual Meeting

Tube Insert

Performance

20-30% average increase in Heat TransferCoefficient (U)

Lower reactor temperature 2-3F

Lower corrosion rates

Lower acid consumption

Increased feed rate


17/23

2007 Annual Meeting

Tube Insert

Installations

Winter 20048/10North AmericaRefinery #6



Fall 20036/6HOVENSARefinery #3Spring 20032/2Hess Port ReadingRefinery #2


Installation DateSets of Inserts/#

Contactors

Location


18/23

2007 Annual Meeting

Tube Insert

Installations

Spring 20072/2North AmericaRefinery #12

Spring 20072/2North AmericaRefinery #11

Spring 20072/2EuropeRefinery #10


Summer 20063/3EuropeRefinery #8


Installation DateSets of Inserts/#Contactors

Location


19/23

2007 Annual Meeting

Tube Bundle

Historical standard is the 1 bundle

1 OD, 10,070 ft2 / 613 tubes

OD, 13,630 ft2 / 1,101 tubes

12 installed tube bundles


20/23

2007 Annual Meeting

Tube Bundle

Performance

Case 1 Replaced 9,800 ft2 with 13,630 ft2

No additional modifications

Olefin feed rate increase ~14-15% increase

@ constant reaction Temperature

Reaction temperature decrease of 4.6F atconstant olefin feed rate


21/23

2007 Annual Meeting

Tube Bundle

Performance

Case 2

Replaced 8,500 ft2 with 12,130 ft2

Replaced 9,800 ft2

with 13,630 ft2

New feed nozzles, rebuilt heads

Olefin feed rate increase ~10% increase @

constant reaction Temperature


22/23

2007 Annual Meeting

Combined Tube

Bundle and TubeInsert Performance

One current installation 42 Contactor

Reactor

Replaced 4,160 ft2 with 5,978 ft2 with Tube

Inserts

Rebuilt head/impeller Reaction temperature decrease of 15F at the

constant olefin feed rate


23/23

2007 Annual Meeting

In Summary

DuPont is continually looking to improve the

STRATCOAlkylation Technology

Reducing hydrocarbon and sulfuric acid

inventories Increasing Contactor Reactor throughput

and/or alkylate product quality (Tube Inserts,

Tube Bundle, Contactor Reactormaintenance)

stratco_alkylationtechnologyimprovements

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