The core function of the cargo ESD system is to stop the flow of the cargo liquid/vapor in case of an emergency in order to bring the whole cargo handling system to a safe static condition. The present document released by SIGTTO was prepared to cover the emergency shutdown system arrangements for the gas carriers.
The book has been arranged in three parts; the first part of the booklet covers the philosophy and some general requirements. the second part addresses the functions of the emergency shutdown system and associated safety systems. Finally, the last part of the book deals with the linked ESD systems. There are several appendices at the end of the book providing some useful supplementary information such as one on ESD processing, pneumatic ESD links, IGC Code requirements applicable to the ESD systems, and others.
The publication was released due to the numerous concerns raised by the members of the organization about the interpretations of the functional requirements and is intended to encourage and promote the use of the linked systems; however, note that it shall not be treated as the technical specification for the ESD system design, it rather sets out the most important requirements to such systems...
In the last 35 years a high number of serious casualties have occurred involving fires in the cargo containment system of liquefied gas carriers, whilst the vessels have been in shipyards. Many of these have resulted in multiple fatalities, environmental damage and serious financial loss to the ship-owner.
It should also be borne in mind that it is not unknown for ships to be arrested and owners superintendents, or representatives, to be held in custody for lengthy periods whilst accidents are investigated. In 1995, the SIGTTO Secretariat undertook research into the subject and published the results at the Balikpapan Panel Meeting in September 1995. At the time this was thought to be sufficient to alert the industry to the problem, but a recent enquiry has shown that since September 1995 there have been 7 reported incidents resulting in 7 fatalities and the constructive total loss of a vessel undergoing repair.
This guide has been prepared by SIGTTO in order to draw attention to the problem and propose risk mitigation measures to those responsible for managing these activities. Whilst this safety guide was being prepared, in July 2001, a fire occurred on a 3200 m3 semi-pressurised LPGC at a repair yard in Slovenia. The fire, which burned for over 2 hours, damaged the structure and insulation of No.1 cargo tank and was caused by hot work during steel-work renewal in the double bottoms. There were no fatalities or injuries.
The first three decades of the LNG industry, i.e. until the end of the 1990s, were dominated by base load projects with long-term sale and purchase and associated shipping contracts, typically of 20 years duration. With such arrangements the project partners had an equity share or knowledge in all facets of the project, from gas gathering to gas distribution, including shipping.
Furthermore, their technical staff had a detailed knowledge and familiarity with all the individual sections of the contractual chain. By the end of the 20th century, however, a short-term or "spot" market was starting to develop within the industry. In this market LNG vessels are hired on "spot" and "short-term" charters, with the charterer often having little or no knowledge of the history of such vessels. This has led to charterers and buyers and sellers of the cargoes drawing upon their oil industry experience and insisting on vetting these vessels prior to accepting them.
This has occasionally raised questions about aspects of the vessels' operation and maintenance that partners in the original long-term projects had previously understood and accepted. One area, unique to the LNG trade, in which this has occurred is the maximum, operationally acceptable, gas concentration to be found in the insulation spaces of the cargo containment system of the membrane-type liquefied natural gas carriers, particularly those of older design.
The present document is mainly intended to provide all members of the Organization with the guidelines of the requirements that are applicable to the testing the LNG cargo handling systems. The scope of the publication shall be considered applicable to the designs featuring established membranes, SPB and spherical tanks.
Note that the content shall not be extended to the prototypes and novel ship designs since they will most probably require some specific approach, for example additional testing. Moreover, this paper shall not be treated as a sort of operational procedures; it is rather an aid to preparation of a specification to be used during the gas trials. The authors have tried to address all items that have to be tested before the vessel is handed-over as well as the testing done after the delivery, at the time of loading of the first cargo.
The figures there in the text of the document are indicative and it would be better to refer to the shipbuilder's/manufacturer's recommendations for figures for the particular ship. It is assumed that the trials are done by the shipbuilder before delivery, which is actually the common practice. The trials themselves are conducted to confirm the correct operation of the handling systems...
This LNG/LPG Officer Experience Matrix is aimed to offer the transparent guidance for proper assessment of the risks relating to the officer complement. It considers a number of elements, including experience in rank, length of sea service, training assessment and experience in LNG/PLG operations.
When evaluating risk in the event of non-compliance with a particular element of the experience matrix, consideration should be given to other mitigating factors, including bespoke training, the manning scale in place, time with the LNG/LPG ship owner/operator the wider competence management systems employed by the ship operator in officer recruitment and development. In the meantime, it is very important to appreciate that subject matrix has been supplied to serve as a tool for the risk evaluation and management.
When dealing with the risk evaluation in case of non-compliance with the specific element of this matrix, due consideration is to be given to other mitigating factors involved, such as the manning scale, bespoke training and others. Careful attention to management of the risks has been widely recognized of the maintenance of the safety record of the ship and environment protection.
Here is a new edition of the LNG Custody Transfer Handbook reflecting the GIIGNL's technical understanding of the best practices. This handbook was prepared and released with the intention to serve as a reference manual assisting readers who want to better understand all equipment used by and procedures available to the GIIGNL members when determining the quantity of the energy of the gas which is being transferred between terminals and gas carrying ships; note that the present publication should not be treated as a technical specification/recognized standard.
At the same time, it shall be underlines that it was not the original intention of the authors of this handbook to provide detailed technical procedures of the ship-shore custody transfer of LNG; they rather tried to set out the practical requirements and issues to facilitate skilled operators to prepare suitable procedures for specific transfer operations.
The book starts with some introduction followed by general formulae and schemes of transfer as well as the instruments used, then there come parts that deal with the volume, temperature and vapor pressure measurement, sampling of gasified LNG, control devices and vaporizers, sampling procedures, gas analysis, calibration methods, density calculation and many other relevant technical info.
This presentation is dedicated to the transportation of liquefied gas. It contains an overview of some methods used for mitigating the risks and describes potential hazards of LNG and LPG, and summarizes various techniques to minimize their risks on the vessels, at terminals and jetties, combined operating practices and procedures, contingency planning. The presentation starts with some historical background.
The marine transportation of LPG started before the World War Two and was conducted in the pressurized containment and in relatively small quantities. Transportation of LNG started several years after that, in 1959. Today, there are more than thousand of gas carriers. The major hazard associated with the marine transportation of all liquefied gases is not their liquefied form but rather the vapor released. The heat is released, subsequently, that may ignite and cause fire.
With regard to the possible pollution of the marine environment, liquefied gases are neither toxic nor persistent so shall not be considered water pollutants; however, possible explosions was obviously cause lethal effects to various marine organisms - but in general the environmental hazard is less than the one of the crude oil spills...
The present publication was written and released by the TGE(standing for Tractebel Gas Engineering) professionals with the declared intention to provide all people who are concerned with transportation, handling and further storage of liquefied gases as well as some chemicals with all technical info that they might require in order to perform their professional duties in a safe and effective manner.
It contains all main physical and thermo-dynamic properties of the above mentioned liquefied gases and chemicals presented in the diagrams and data tables. The team of authors of the handbook hopes that it will serve as a useful guidebook for those who require the basic technical information.
There are thermo-dynamic properties of various liquids/gases, safety properties of these substances, diagrams presented in a half-logarithmic scale and provided with explanations and descriptions, diagrams summary and diagrams of pure substances for LNG and chemicals are also there together with the conversion factor tables. In short, this publication is recommended to any people who are directly or indirectly involved in any activities relating to the safe transporting and handling of all those substances.