Crude Preheat Management for Challenged and ... Crude Preheat Management for Challenged and Unconventional Crudes COQA Meeting San Antonio 7th March 2013 Greg Savage

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Crude Preheat Management for Challenged and Unconventional Crudes

COQA Meeting San Antonio7th March 2013

Greg Savage

Copyright© 2013 Nalco Company. All rights reserved

Increased Fouling Potential From New Crudes2


Energy Management and Fouling Control OverviewFouling problem solving:

Evaluate mechanical, operational, and chemical root causes

Identify fouling mechanism

Select solution

Monitor Performance

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LOCATION

Crude Preheat Exchangers

Crude or Vacuum Furnace

Gas Oil Loop

Resid Exchangers

Tower Tray / Packing

Asph

alte

nes

Cor

rosi

on

Inor

gani

c sa

ltsPo

lym

er g

umC

okin

g

Observed Fouling Locations in the Crude Unit


WHAT CAUSES FOULING?Mechanical – Operational – Chemical Causes

MOC

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Mechanical & Operational Causes

Poor tank farm practices Incompatible Crude blending Slops containing ash, gums, coke, etc.

High skin temperatures or heat fluxes

High solids level in crude

Poor desalting

Other possible causes Low exchanger velocities Chemical additive treatment

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Common Fouling MechanismsCrude Preheats – Unconventional Crudes

Deposit Cause

Asphaltenes Destabilization of asphaltenes

Inorganic Solids High solids level in unconventional crudes

Polymeric gum Co-processing reactive streams or chemical additive treatment

Coke Dehydrogenation of asphaltenes & PNA’s

Inorganic salts Poor or no desalting, amines

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HOW DO WE FIND THE ROOT CAUSE?

MOC

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Root Cause Analysis: Fouling Mechanism

Deposit analysis Identify and quantify elemental components Interpret organic and inorganic nature

Stream characterization Identify and quantify fouling precursors

Fouling simulation and Chemical selection Simulate process fouling (mechanisms) Screen chemicals

Together help describe probable fouling mechanisms

MOC

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Deposit Analysis Summary10

Analysis 80% Eagle Ford 25% Canadian75% Domestic light

Organic Materials 11.0% 95.2%Soluble Organics 5.0% 31%

Coke, polymers 6.0% 64.2%Inorganic Materials 89.7% 4%

Iron Salts: 40.6% 2.4%Other Salts including Volatile Salts: 49.1% 1.6%

Carbon/Hydrogen Mass Ratio 10.0 11.2


Bakken Stream Analysis

The Bakken Crude is Low in Asphaltenes and Metals

High Solid Nos.

Low in Aromatics

Highly Paraffinic

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ANALYSIS Flashed Crude Oil

Al 0.3 ppmCu / Fe 0.06 / 4.1 ppmNi / V 0.61 / 0.22 ppmNa / K 4.1 / < 0.2 ppm

Ca 0.6 ppmMg < 0.2 ppm

Solids 39 lbs / MbblsAcid No. 0.07 mg KOH/g

Naphthenic Acid < 0.1 mg KOH/g

Asphaltenes 0.1 wt%Aromatic 8.8 wt%Paraffin 37 wt%Polar 1.4 wt%

Aromatic (NMR) 14.6 mole%


75% Eagle Ford Stream AnalysisHigh solids level made up of inorganic material

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Analysis Filtered TotalAl 0.17 ppm 4.9 ppmCa 1.4 ppm 15 ppm

Cu / Fe 0.16 / 3 ppm 0.21 / 16 ppmMg < 0.12 ppm 1.6 ppm

Ni / V 8 / 22 ppm 8 / 22 ppmNa / K 0.4 / < 0.3 ppm 34 / 1.2 ppm

Cl 59 ppmSolids 150 lbs/MbblsWater 0.2 vol %BS&W 0.4 vol %


Laboratory Furnace Fouling Simulation

HLPS Test Equipment Bakken fouling

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Characterization Of Deposit From HLPS

Analysis Wt %Fe 18.0S 17.0

Ca 0.5C 51.0H 5.0N 0.8

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Left to Right: Blank, Products A, B, C, D Elemental Maps Iron = red, Sulfur = green, Phosphorus = blue


Crude Stability Index (CSI) 20+ years

0

2

4

6

8

1 0

1 2

0 8 1 0 1 2 1 4 1 6 1 8 2 0

Volume of Aliphatic Solvent

Solvent Dilution

Flocculation Point

Solvent Dilution

Commencement of Solvent Addition

0

2

4

6

8

1 0

1 2

0 8 1 0 1 2 1 4 1 6 1 8 2 0

Volume of Aliphatic Solvent

Solvent Dilution

Flocculation Point

Solvent Dilution

Commencement of Solvent Addition

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Component and Blend CSI indicating Potential Incompatibility


Crude Stability Determination: Blends

28.644.5

22.6

CSI

Unconventional blend with few asphaltenes


Assessment of Shale Condensate on Crude StabilityIdentify blend instability region

0

10

20

30

40

50

60

70

80

90

100

0 10 20 30 40 50 60 70 80 90 100

Cru

de S

tabi

lity

Inde

x

Percentage of WCS in Bakken


Stability Change with Process Temperature


Asphaltene Dispersant Performance using CSI


Intrinsic Stability Analyzer• Intrinsic stability “S” concept as per ASTM D 7157

• Simple to operate, user friendly

• Results obtained in about 20 minutesS = StabilitySo = Solvency Power of OilSa = Asphaltene Solubility


Blending Order Stability Study

?


Fouling Control Strategies

Do nothing

Mechanical options

Operational options

Evaluate chemical solution(s) Understand mechanistic function of products

Improved monitoring Field support tools

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Tracking treatment performance

Midcontinent Domestic with Canadian


Tracking treatment performance25


Acknowledgements

Gregg McAteer

Laura Copeland

Sam Lordo

Keith Gawrys

Christopher Russell

Michael Braden

John Garcia

Kailash Sawhney

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Disclaimer: The contents of this document are, to the best of our knowledge, accurate at the date ofpublication. We shall not be liable for any loss or damage whatsoever resulting from reliance on its contents. Allwarranties as to fitness for purpose or otherwise (howsoever made or implied) in respect of this publication areexcluded.

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Crude Preheat Management for Challenged and ... Crude Preheat Management for Challenged and Unconventional Crudes COQA Meeting San Antonio 7th March 2013 Greg Savage