GAS TANKER COMMITTEE #4 - Intertanko · GAS TANKER COMMITTEE #4 1 FSRU-Critical link in Global LNG...

DNV GL © 2015 28 August 2017 SAFER, SMARTER, GREENERDNV GL © 2015

12 October 2017

GAS TANKER COMMITTEE #4

1

FSRU-Critical link in Global LNG Supply chain

Singapore 12th October 2017

Lian-Gee CHUA, DNV GL

DNV GL © 2015 28 August 2017

200Maritime officesglobally

4,300Maritime staffworldwide

ENERGYOIL & GAS

BUSINESS

ASSURANCE

MARITIME

Maritime is our core industry

12,400 ships & mobile offshore units

in DNV GL class, 278 mGT

Strong presence in all ship segments

Dedicated ship type expert teams

support our clients worldwide

Among top performing class societies

in Port State Control statistics

ABOUT DNV GL -The leading classification society

2

SOFTWARE

LIFE

SCIENCES

13,500employeesgroupwide

5%revenue invested in R&D activities

DNV GL © 2015 28 August 2017

This presentation seeks to outline and discuss the key considerations for a FSRU newbuild or conversion project

FSRU is a “fast track” way of opening

energy markets to natural gas

Reduced construction time

Cost much less than land based

alternatives of a similar size

Face less local opposition than new

terminals onshore (“not in my backyard”)

Alternative to pipeline gas for political

reasons

Has flexibility with respect to location and

use

– Can be reused at a new location at a later stage

– Many FSRUs have valid SOLAS Certificates and

can trade as LNG Carriers

3

The world needs energy and FSRUs can be the possible solution

Several key issues needs to be considered for a new FSRU project

There are many issues to take into

consideration for a new FSRU newbuild or

conversion project

This presentation seeks to outline the key

questions that must be answered and

discuss different solutions

DNV GL © 2015 28 August 2017

Currently there are 24 FSRUs in operation, mainly located in Middle East & North Africa and South America

4Disclaimer: Information accurate as of October 2016

DNV GL © 2015 28 August 2017

DNV GL has been at the forefront of the FSRU development and classifies more than half of the global FSRU fleet today

5

61 %off all FSRUs classed by

DNV GL

1962 20172008 2009 2015

DNV GL has been

part of defining the

LNG Carrier

industry

First

classification

society to publish

rules for gas

carriers in 1962

First conversion FSRU –DNV

classed Golar Spirit

First newbuild FSRU – DNV

classed FSRU Neptune

Development of

Classification Note

for FSRUsLatest revision of

REGAS rules Projects:

19 FSRU NB

4 FSRU Conversions

DNV GL © 2015 28 August 2017

Certain key considerations for FSRU/FSU (both NBs and conversions) will impact the asset’s specifications and commercial value, as well as the project cost and schedule

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Site selection1

- Safety & security

zone

- Defined exclusive

zones

Storage

Systems3

- Type?- Capacity of tank?- Logistical challenges

Drydocking4

- Continuous operation w/o drydocking (if accepted by flag & port administrations)?

Regas Trains5

- Capacity/Send out?- Redundancy - Expansion possible?

Classification

& Propulsion2

Flexibility, cost and statutory requirements based on: - Ship or Offshore classification- propelled or non-propelled unit.

Vaporisation6

- Vaporisation alternatives- Local environment restrictions

Mooring7

- Geotechnical

conditions

- Turret mooring, or

spread mooring

- Moored to jetty?

Manning8

- Cost of crew,

qualifications?

- Statutory

requirements?

Additional topics

for conversions9

- Reinforcement of hull structure

- Work needed for lifetime

extension of old assets?

DNV GL © 2015 28 August 2017

Safety and Security zones

Safety Zone

– A Safety Zone is in place to prevent a natural gas release from igniting and leading to a

serious incident

– The safety zone required on water side is referred as the Ignition Exclusion Zone

(IEZ)

– Onshore Safety Zone is used for land clearance and requirements applicable to

onshore side (determined by QRA)

– Marine Exclusion Zone (MEZ) is a defined distance from the facility (FSRU) where

vessels can be prevented from passing

7

ManningMooringVaporisationRegas TrainsDrydockingStorageClassification

& PropulsionConversions

2 3 4 5 6 7 8 9Site

selection

1

DNV GL © 2015 28 August 2017

Defined Exclusion Zones (Ignition and Marine)

Marine Exclusion Zone defined based upon passing traffic impact

Ignition Exclusion Zone (IEZ) defined based upon gas release and ignition likelihood

Onshore QRA study will be required to determine 10-5 contours, within which land should be

owned by FSRU owner

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2 3 4 5 6 7 8 9Site

selection

1

DNV GL © 2015 28 August 2017

Classification: Ship or Offshore Certification?

A vessel which:

– Conducts regasification activity

– Design based on North Atlantic

environmental conditions

– Regular dry-docking or continuous

operation without dry-docking if

accepted by flag and port

administrations

– Has valid IMO Certificates

Ship with propulsion or

barge

Majority of vessels with ship

certification

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A vessel which:

– Permanently moored on location

– Design based on site-specific conditions with

special focus on fatigue and corrosion

– Does not intend to regularly dry-dock

– Does not need IMO Certificates

SHIP CERTIFICATION OFFSHORE CERTIFICATION

+1A

Tanker for

liquefied

gas

REGAS

+OI

Floating

Offshore

LNG

Storage

REGAS

Two alternatives to classification – “ship” and “offshore”

Both approaches have been accepted by Port Administrations

Modified POSMOOR notation if

no propulsion capability

Barge without propulsion



2 3 4 5 6 7 8 9

Site selection

1

DNV GL © 2015 28 August 2017

Storage: Which tank type & size?

Type

– Membrane, MOSS or C-tank

– Majority of vessels with membrane tank

Capacity/Size of tank

– FSRU sizes are 125 000 to 263 000 m3

– Converted Moss FSRUs are normally around

125 000 m3

– NB FSRU are normally around 170 000 m3

(as other NB LNG Carriers)

Logistical challenges

– Measures to reduce/eliminate the risk of

sloshing damage to the tanks

– Transfer time

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Picture courtesy: Petrobas, GTT



2 3 4 5 6 7 8 9

Site selection

1

DNV GL © 2015 28 August 2017

Drydocking: Possible with continuous operation w/o drydocking?

FSRU operation + option of gas carrier

– Regular 5 years dry-docking intervals

FSRU operation

– Continuous operation without dry-docking possible if

accepted by flag and port administrations

– Case by case acceptance by class and authorities

– Class notation: TMON, BIS

– Sea valves

– Coating in ballast tanks

– Active and passive corrosion protection

– All required inspections to be carried out afloat

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Picture courtesy: Samsung Heavy Industries



2 3 4 5 6 7 8 9

Site selection

1

DNV GL © 2015 28 August 2017

Regas train: Capacity and availability

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Spare/stand-by train

– Normal set-up: 3 to 4 trains

– Normal with 1 train in standby

– Train configurations: 1x100%, 2x100%,

2x50%, 3x50%

Capacity per train

– Typically 250 MMSCFD (Million Standard Cubic

Feet per Day)

Availability

– Based on receiving unit’s requirements

– Maintenance considerations

Expansion possible?

Note: 1 m3 LNG = 21,55 MSCF (60 °F)



2 3 4 5 6 7 8 9

Site selection

1

DNV GL © 2015 28 August 2017

Vaporisation: Alternative systems

Vaporisation alternatives

– Open loop, closed loop, combination (open

rack, air panel)

– Heating Medium: Seawater, propane,

glycol, steam

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Challenges

– Corrosion choice of materials, water

velocity

– Marine growth chlorine

– Environmental restrictions: Temperature

difference between inlet and outlet of

seawater – local requirements

EX: Open loop with seawater heating:



2 3 4 5 6 7 8 9

Site selection

1

DNV GL © 2015 28 August 2017

Heating system for LNG vaporizer

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EX: Water/Glycol system

Means shall be provided protect the vaporizers against freezing of heating

medium

Means shall be provided to detect leakage of high pressure LNG/NG into the

heating fluid and to prevent overpressure in the heating system



2 3 4 5 6 7 8 9

Site selection

1

DNV GL © 2015 28 August 2017

Mooring: Which alternative?

Turret mooring (Single point mooring)

– Weather-vaning freely

– Heading control to limit roll motions

– Export of natural gas to the onshore network

through turret or flexible risers

Spread mooring

– Currently no FSRUs with this mooring

alternative

Permanently moored to a jetty

– Used in benign water conditions (protected

location)

– Export of natural gas to onshore network

through loading arms or flexible hoses

15

Picture courtesy: Høegh LNG



2 3 4 5 6 7 8 9

Site selection

1

DNV GL © 2015 28 August 2017

Manning: Requirements for crew

More than 10% additional crew on FSRUs

today compared to LNGC

Manned 24/7

Key Questions:

– Cost of crew?

– Which qualifications are needed?

– What are statutory requirements?

– Requirements to use local crew?

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Picture courtesy: Hoegh



2 3 4 5 6 7 8 9

Site selection

1

DNV GL © 2015 28 August 2017

Conversions: What are some additional issues to be considered?

17

Fixed loading

armsHP Manifold REGAS vent Mast

REGAS Process

equipment

Picture courtesy: Golar LNG

Reinforcement

of hull structure



2 3 4 5 6 7 8 9

Site selection

1

DNV GL © 2015 28 August 2017

Other important topics for NB and conversions include…

BOG Management: Power generation and send out in normal and abnormal operations

Rollover: Design measures to help reduce the risk of stratification and subsequent rollover

Cargo Tank Pressure: Operational advantages with increased tank pressure

Depressurizing/blowdown system: High/low pressure system

Cryogenic protection of hull structure: Booster pumps, vaporizers, suction drum

HAZID: Dispersion analysis, heat load calculation, relocation of equipment, escape routes

Quantitative risk assessment: Possible requirement from charterer

18

DNV GL © 2015 28 August 2017

SAFER, SMARTER, GREENER

www.dnvgl.com

Thank you for your attention

Questions?

19

Lian-Gee CHUA

[email protected]

mailto:[email protected]

GAS TANKER COMMITTEE #4 - Intertanko · GAS TANKER COMMITTEE #4 1 FSRU-Critical link in Global LNG...

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