Establishing Integrity Operating

Windows (IOW’s)*

Inspector Summit

January 27, 2006

Galveston, TX

John Reynolds

Pro-Inspect, Inc.

Steamboat Springs, CO, USA

*Based on article published

in Inspectioneering Journal,

April, 2005

2

Outline for this Presentation

• The 10 Shell (US) Process Safety Initiatives (PSI)

• The Pressure Equipment Integrity (PEI) Initiative

• Corrosion Control Documents (CCD)

• Integrity Operating Windows (IOW)

• Standard and Critical IOW’s

• Integration of IOW’s into the 10 PSI’s

• Training of Operators on IOW’s

• The Pressure Equipment Integrity Pyramid

3

Ten Process Safety Initiatives

(PSI) – Initiated in May, 2000

• Pressure Equipment Integrity (PEI) - IOW creation process

• Ensure Safe Production (ESP) - IOW monitoring process

• Operator Training and Procedures - IOW knowledge transfer

• Management Of Change (MOC) - IOW change process

• Investigations – 3 Levels up to RCA

• Protective Instrument Systems (IPF – “SIL”)

• Reliability Centered Maintenance (RCM)

• Causal Learning

• Audits and Assessments

• Process Hazards Analysis (PHA)

4

Process Safety Initiative

Metrics• Each of the 10 PSI’s were required to have four

main metrics to track implementation progress (10 X 4 = 40 metrics total)

• For the PEI process safety initiative we tracked:- Numbers of Corrosion Control Documents (CCD’s) completed

- Numbers of process units with RBI completed

- Numbers of process units with all IOW’s implemented

- Numbers of operators trained on their CCD & IOW’s

• But there was only one bottom line metric for the

aggregate of the ten process safety initiatives –>numbers of process safety incidents per year

5

Results of the Process Safety Initiatives

YTD Totals

19

23

20

15

9

3

0

5

10

15

20

25

1999 2000 2001

2002 2003 2004Numbers of

Process Safety

Incidents

in 6 years after

implementation–

A real success

story

6

Primary Aspects of the

Pressure Equipment Integrity

(PEI) Initiative• Identify all necessary Integrity Operating Windows

(IOW’s)

• Create OEMI Teams (Operations - Engineering -

Maintenance - Inspection) in each operating area to

create and manage CCD’s and IOW’s

• Create Corrosion Control Documents (CCD’s), which

document all process IOW’s

• Train operators on the CCD and IOW’s

• Implement IOW’s and Risk-Based Inspection (RBI)

• Implement PEI Focused Asset Integrity Reviews (FAIR®)

to monitor progress of the PEI Initiative

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RBI

IOW’s

CCD’s

Management of

Change

101 Essential Elements

PEI PSI

Pyramid

8

Corrosion Control Documents –

Contents• Relatively comprehensive documents for managing equipment

degradation

• Description of the process unit and process conditions

• Shutdown and start up conditions that may affect corrosion and degradation mechanisms, as well as normal operation

• Process Flow Diagram (PFD) and Materials and Corrosion Diagram (modified PFD showing construction materials)

• Corrosion Control Loops (areas of similar corrosion within the PFD) e.g. overhead system, slurry system, reflux system, etc.

• All potential types of degradation (and fouling) in each process unit and history of problem areas

• Quantitative and predictive models for degradation mechanisms

• Vital corrosion control procedures, injections, inhibitors, etc.

• Recommended inspection & corrosion monitoring, process changes,

construction materials changes, etc.

• Integrity Operating Windows (IOW’s)

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Corrosion Control Documents –

Construction• Unit specific CCD’s completed by an OEMI

team which includes:- Site corrosion engineer/specialist

- Unit process engineer

- Unit inspector

- One or more experienced unit operations representatives

- Facilitator (knowledgeable / experienced corrosion engineer)

• Final document represents an agreement

between the OEMI Team involved and clearly

benefits by the synergistic interaction of all team

members

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Establishing Integrity Operating

Windows• Historical operating, maintenance & inspection records

• Design data; lab data; operating data

• Metallurgical and corrosion data and modules

• Process chemistry and engineering knowledge

• Reactive chemistry knowledge

• Recommended practices (industry and company)

• Process and corrosion modeling tools

• Subject matter expertise and experience (heavy dose)

Result: Reasonable, practical IOW’s – not too conservative – not non-conservative

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Integrity Operating Windows

Operating

WindowOperating

Window

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Integrity Operating Windows –

Examples• Typically fall into 2 categories:

• Physical- Various limits on pressures and temperatures, including design,

operating, partial pressures, dew points, dry points, heating and cooling rates, delta P, etc.

- Flow rates, injection rates, inhibitor dosage, amperage levels on Alky contactor motors, slurry content, hydrogen flux, vibration limits, corrosivity probes, etc.

• Chemical- pH, water content, acid gas loading, sulfur content, salt content in

crude, NH4HS content, NH3 content, TAN, acid strength, amine strength, inhibitor concentration, chloride contamination levels, oxygen content, etc.

13

IOW Example – Hot Hydrogen

Service• Mechanical design window set by the design code e.g. ASME

• IOW set by material limit for high temperature hydrogen attack in API RP 941

• SOR process temperature definitely within the IOW

• EOR process temperature possibly beyond the IOW –need to know the hydrogen partial pressure and duration of EOR conditions

Temperature

Pressure

Mechanical Design Limits

SOR Process Temp

EOR Process Temp IOW

Based on H2 pp Based on

Total Pressure

14

Integrity Operating Windows –

Typical Numbers per Operating Unit

(before & after an intensive review)

• Typically start with 5 -10 IOW’s that may

already be in place, along with other operating

quality variable limits

• Typically end up with 30 – 50 IOW’s with about

5 -10% being critical limits (requires drastic

and/or immediate action), and the rest being

standard limits (requires attention within a

specified timeframe to get back into control)

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Definitions: IOW Critical Limit

A limit at which the operator has one last opportunity to return the process to a safe condition and, if exceeded, could result in one of the following in a fairly short timeframe:

• A Catastrophic Release of Hydrocarbons or Hazardous fluids

• Loss of Containment

• Non-orderly Shutdown

• Significant Environmental Impact

• Other Unacceptable Risk

16

Critical IOW Limit –

Examples• Boiler Feed Water Level

- Lost of boiler feed water level could quickly cause boiler tube rupture

• Hydroprocess Reactor Temperature - Metal temperatures below the MDMT could give rise to brittle

fracture

• Heater Tube Skin Temperature- Tube could rupture quickly if overheated, caused, for

example, by a no flow or hot spot condition.

• Sulfuric Acid Strength in Alkylation- Too low acid strength could cause runaway reaction

17

Definition: Standard Level

A limit that, if exceeded over a defined

period of time, could cause one of the

following to eventually occur:

• A catastrophic release of hydrocarbons or hazardous fluids

• Loss of containment

• Non-orderly shutdown

• A negative impact to the long term unit performance and its

ability to meet turnaround run length

• Excessive financial impact

18

Standard Level Examples

• REAC NH4HS Concentration- Corrosion of the air cooler and downstream piping

• Heater Tube Skin Temperature- Metallurgical creep could lead to eventual tube failure.

• Crude Fractionator Dew Point Temperature- Sustained operation below dew point could cause damage to

fractionator internals or potential loss of containment.

• pH of Crude Tower Overhead- Sustained operation below standard pH level could lead to

corrosion of tubing and piping and potential loss of containment.

• Desalter Outlet Salt Content- Sustained operation above standard level could lead to corrosion

and potential loss of containment

19

Integrity Operating Windows –

Successes• In the CCD review, one IOW team noticed that a previous project had installed the wrong construction materials –immediate inspection revealed significant HTHA damage

• An operator on the team disagreed with the unit process engineer and said that “we actually operate much hotter than you think because we use the by-pass” – immediate inspection revealed significant localized damage

• A corrosion engineer questioned the higher level of NH4HS in the REAC system of an HCU – immediate inspectionrevealed a previously-missed localized spot of significant corrosion

• An IOW was set on NH4HS concentration at another refinery, which then began to take routine lab samples –soon thereafter discovered the concentration was too high and took steps to increase wash water and adjust feedstock

20

Operator Training on CCD’s and

IOW’s• Level 1

- Awareness and Overview of the PEI Process Safety Initiative

- SSA Video / CCD / RBI / OEMI / Operator Training

• Level 2- Introduction to Corrosion Control Documents

- What they contain; where they’re stored; how to use them

• Level 3- Details contained within each operator’s unit-specific CCD

- Specific IOW’s and the reasoning behind them

- What can happen if the IOW is exceeded

21

RBI

IOW’s

CCD’s

Management of

Change

101 Essential Elements

PEI PSI

Pyramid

22

Implementing Risk-Based Inspection

(RBI)• Another major part of our pressure equipment integrity process safety initiative

• We use both a Shell developed more qualitative RBI (S-RBI), as well as the more quantitative API RBI, both successfully for different needs at different sites

• But RBI will not be covered today – a topic for another day, if you like

• Suffice it to say that any inspection program, be it risk-based, condition-based, or time-based may not be fully reliable without effective identification and implementation of integrity operating windows (IOW’s)

23

Integration of CCD’s, IOW’s &

RBIConfidence in plant integrity

Creating the CCD:

Type of degradation

Location of degradation

Susceptibility to degradation

Degradation rates

IOW limits:

Determination & management of the operating limits to avoid degradation

RBI planning:

Method of inspection

Where to inspect

Frequency of inspection

Feedback

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Integration of Multiple Work Processes

Leading To Sustained Asset Integrity

Design and

Materials Selection Corrosion

Control & IOW’s

Risk-Based

Inspection

Long Term Asset Integrity

Asset integrity management is a balancing process

designed to achieve lowest total cost of ownership

Focused Asset Integrity Reviews

25

Along with Asset Integrity Comes

Proven Better Process Safety

Performance YTD Totals

19

23

20

15

9

3

0

5

10

15

20

25

1999 2000 2001

2002 2003 2004Numbers of Process

Safety Incidents

in 6 years after

implementation in

Shell (US) Refining

Operations – Facts,

not just hopes for

the future

26

27

Experience with Integrity Operating

Windows (IOW’s)*

Time for Discussion

John.Reynolds@shell.com

Recently retired from

Shell Global Solutions (US) Inc.

*Based on article

published

In Inspectioneering

Journal, April, 2005