LNG Shipping Knowledge 3rd Edition

With the rapid growth of LNG shipping, the introduction of a system of internationally recognised and structured training programmes was necessary. In 2005, the Society of International Gas Tanker and Terminal Operators (SIGTTO) released the first version of its ‘LNG Shipping Competency Standards’ to provide guidance and suggested best practice for the industry. A second edition was published in 2008. This third edition was published in 2020 to incorporate developments within the LNG industry, including the latest updates to The International Code for Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (IGC Code).

At almost 500 pages, this publication covers all areas of LNG carriage and care by sea.

Transportation of LNG by sea commenced in 1958 when the ‘Methane Pioneer’ carried 5,000 m3 of LNG from the USA to the UK. Since then, particularly in the 21st century, LNG shipping has grown rapidly.

To put this level of advance in context, in 2006, the world fleet of LNG carriers was over 200 ships. At the beginning of 2020 there were 540 LNG carriers in service, with over 130 LNG carriers on order. In 2019, LNG carriers carried out 5,701 trade voyages.

Over the last 60 years, the size, capacity and complexity of LNG carriers has increased significantly. In addition, the technology has continued to evolve in respect of propulsion plants and cargo management systems. The commercial nature of LNG shipping has also evolved, as LNG is increasingly traded and used as an energy source around the world. Initially, LNG carriers were dedicated to a specific project, however, LNG operations have now developed into long term and spot charters.

With the rapid growth of LNG shipping, the introduction of a system of internationally recognised and structured training programmes was necessary. In 2005, the Society of International Gas Tanker and Terminal Operators (SIGTTO) released the first version of its ‘LNG Shipping Competency Standards’ to provide guidance and suggested best practice for the industry. A second edition was published in 2008. This third edition was published in 2020 to incorporate developments within the LNG industry, including the latest updates to The International Code for Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (IGC Code).

The SIGTTO ‘LNG Shipping Competency Standards’ summarise the minimum tasks and knowledge considered necessary, relative to the area of individual responsibility. This publication, ‘LNG Shipping Knowledge’, follows that format, providing the underpinning knowledge meeting the recommendations of the third edition of the ‘LNG Shipping Competency Standards’. This makes this publication a powerful and useful support tool for understanding modern LNG shipping.

During the course of the construction of this publication, technical expertise has been sought across many professional sources.

As LNG shipping possesses an excellent safety record, with very few incidents compared to similar segments of the shipping industry, it is essential that companies and individuals continue to invest in training to enhance and improve their knowledge and awareness of LNG shipping.

Acknowledgements
Introduction

1 LNG Fundamental Knowledge and Understanding
1.1 Physics and Chemistry
1.2 Principles of Design
1.3 Regulations and Guidance
1.4 Principles of Tank Atmospheres
1.5 Properties of Materials
1.6 Hazards of LNG and Relevant Gases
1.7 Environmental Impact
1.8 Risk Assessment
1.9 Individual Responsibilities
1.10 Contingency Plans
1.11 Record Keeping
1.12 Planning

2 LNG Equipment
2.1 Cargo System – Tank Construction
2.2 Air and Inert Gas Driers
2.3 Inert Gas Generator
2.4 Nitrogen Systems
2.5 LNG Vaporiser
2.6 High Duty Compressor(s)
2.7 Low Duty Compressor(s)
2.8 Gas Heaters
2.9 Forcing Vaporiser
2.10 Cargo Pumps
2.11 Spray Pumps
2.12 Cargo Tank Protection Devices
2.13 Cargo Line Protection Devices
2.14 Cargo Space Protection Devices
2.15 Cargo Liquid and Vapour Valves
2.16 Cargo Tank Protection System
2.17 Reliquefaction Plant (if fitted)
2.18 Gas Combustion Unit (Oxidiser)
2.19 Regasification Plant
2.20 Cargo Related Spaces

3 LNG Support Systems
3.1 Nitrogen Pressurisation and Purge
3.2 Cofferdam Heating System
3.3 Fixed Gas Detection
3.4 Portable Gas Detection Equipment
3.5 Emergency Shutdown System (ESDS)
3.6 Emergency Mooring Release
3.7 Water Curtain
3.8 Drenching System
3.9 Fixed Dry Powder Installations
3.10 Level Gauging Systems
3.11 Custody Transfer Measurement System (CTMS)
3.12 Certified Safe Electrical Equipment
3.13 High Voltage Systems
3.14 IAS System
3.15 Turbo Alternator Control Systems
3.16 Propulsion Types
3.17 Gas Combustion Systems

4 LNG Standard Operations
4.1 Cargo Tank Cleaning
4.2 Hold Space and Cargo Tank Drying
4.3 Nitrogen Purging of Containment System
4.4 Inerting of Cargo System
4.5 Ship and Shore Preparation and Manifold Connection
4.6 Gassing Up (Purging) of Cargo System
4.7 Cooldown of Cargo System
4.8 Loading
4.9 Loaded and Ballast Passage
4.10 Discharging
4.11 Warm-Up
4.12 Gas Freeing
4.13 Aeration
4.14 Ship to Ship (STS) Preparation and Manifold Connection
4.15 Ship to Ship Transfer of Cargo

5 LNG Non-Standard and Emergency Operations
5.1 Types of Non-Standard and Emergency Operations
5.2 Multiple Cargo Pump Failure in One Tank
5.3 Gas Freeing a Single Tank
5.4 Part Load and Discharge
5.5 Non-Availability of Key Equipment
5.6 Loss of Gas Handling Capability
5.7 Prolonged Loss of Power to Cargo and Ancillary Systems
5.8 Loss of Primary Containment
5.9 Ballast Tank Leakage into Containment Space
5.10 Nitrogen Supply Failure
5.11 Jettison of Cargo
5.12 Overfilling of a Cargo Tank
5.13 Loss of Cargo Pipeline Containment
5.14 Failure of Integrated Automation System
5.15 Uncontrolled Release of Cargo

6 LNG Commercial Considerations
6.1 Terms and Conditions in Use 446
6.2 Vetting and Inspection Processes
6.3 Ship/Shore Compatibility Assessment

Annex I – Reference Documents
Annex II – Definitions

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