cool down gap presentation

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“The Cooldown Gap”

Session 15, Supplemental Gas

LNG

LNG

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· n erna onaPresenter: Jeff Beale

Coauthor: Osifo Akhuemonkhan

May 20, 2009


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Presentation Outline

Introduction

Explanation of “The Gap”

• Preparation

• ryogen c p ng ryou Cooldown / Start-Up Gaps

• LNG Tank Cooldown

SummaryH

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CH·IV International2


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– ·www.CH-IV.com

Offices near Baltimore & in Houston

• Conceptual Design / Pre-FEED

• Front End Engineering Design (FEED)

• ’ ,

• Commissioning / Start-Up Support

• Trainin

• Operations Support

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Introduction – CH·IV International

Recent LNG Terminal Commissioning Experience

• Multiple LNG terminals in Europe

• World’s first GBS LNG import terminal – on going• Dom n on Cove Po nt LNG Expans on

• Energía Costa Azul (Mexico)

ecent ront n ng neer ng es gn• Oregon LNG

• parrows o n

• Downeast LNG• co ec r ca

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Introduction – CH·IV International

Owners Engineering

• EcoElectrica

• Cove Point Reactivation• Lake Charles Expansion

• Energía Costa Azul (Mexico)

• ameron• Piedmont Natural Gas (Peakshaver on hold)

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LNG Terminal Phases

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“ ” ga ons o e ng neer ng, rocuremen an

Construction (EPC) contractor are set early. Typically, limited clarification on the particulars of

commissioning & start-up.

Owner / operator does not recognize what is neededuntil well into the construction.

EPC’s definitions of “needs” does not always agree

with owner.

There in lies the “Gap.”

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“ ”

ng neer ng vs. pera ons

(Too bad it’s not Engineering & Operations)• Engineering – Project Control

• Time & Mone

• Responsibility last 3 – 5 years

•

• Safety & Reliability

•

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pe ean ness er ons ruc on

• Debris and/or standing water usually presentupon completion of construction.

• This can find its wa into valve seats and

compromise the valve integrity.

•

pump bearings and cooling paths.

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ere w a ways e some e r s an poss y

standing water, but how do we minimize theamounts??

• Store i in com onents with end ca s in lace.

• Delay insulation (particularly foam glass) until as

.

• Use valve operating management system, avoidunnecessary open ng an c os ng.

• Keeping inspection covers on when not in use.H

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’ . wner pera or s ou se e s an ar or

pipe cleanliness well in advance ofcompletion of construction (ideally in

contract .

EPC Contractor should provide records

.

Owner/Operator should conduct independentchecks and reviews of piping.

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“ ”

“ ” .

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• At cryogenic temperatures any water (vapor) will.

• Ice can – • Foul strainers

• Scratch “Tight Shut Off” valve seats• Gaul bearings

• Plug pump cooling paths

• Reduce insulation effectiveness

, positive pressure – piping “breathes.”

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Dr out cont’d

LNG Tank Dryout• Typically the responsibility of tank contractor

• Review purging / sparging design• Annular space as well as inner tank

• Must assure systems are completely dried • ax mum - ew po n

• Design review needs to assure adequate testing pointswill be available

• Media

• Nitrogen• Dry Air

– Will require total N2 purge prior to LNG cooldown

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Dr out cont’d

Cryogenic System Dry-Out

• vo one ryout

• If Contractor responsible:• How is dry media provided?

• Assure / Review detailed procedures with logs

• Provide independent confirmation – Acquire “Company” hygrometer

• Areas of concern

– Dead legs

– ow pa o s ruc ons c ec va ves, e c.

– Free water - Low points

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CH·IV International

,

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Dr out cont’d

Cr o enic S stem Dr -Out

• If Owner / Operator Responsible:

•

– Heat?

– Pressure cycle

– Low pressure Sweep – Sweep & Soak

• Choice of media

– Nitrogen

–

– Rental dry air units

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Wh C ld ?


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Why Cooldown?

i erentia emperatures

• LNG is “sneaky” fast

“ ”• g eren a empera ure prov es g e pa

• Controlled pipe movement

• 3" shrinkage per 100 feet

• Large diameter pipe bowing

• Can lift pipe off supports

• What’s not “large” diameter?• Pipe anchor / support damage

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rec e y an con rac or

Duration of 24 to 72 hours

Substantial temperature monitoring necessary

oo own contro e y spray contro va ve

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-

Was this planned for?

Use LNG Transfer Line

• • Geysering in cooldown line, need to release the

.

• Choking at spray nozzles

se rec rcu a on ne ava a e

• Smaller pipe, less heat gain• Provide isolation valves in design

• Temporary crossovers / connectionsH

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If you are going to flare your cooldown gas,

consider the neighborhood -

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All piping over 10" (8"?) should be pre-cooled.

• What does the EPC say?

. . .Early design

• Once through

• Recirculate using vapor return blowers

• Use cold vapor from tank • Vaporized LIN/BOG/Trickle Cool

• Local in ectionH

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o om on y op on y o

Permanent vs. Tem orar

Local vs. Remote? Or combination?

nsta at on• Dry, continuous contact

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nce co , ry o eep p p ng a way

Avoid thermal c cles and look out for:• Pipe movement

• Insulation breakdown

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Thank youThank you


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Thank youThank you


-. .

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cool down gap presentation

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