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 latest edition of the textbook published by McGuire and White was published by Witherby in 2000 and covers following important aspects of the liquefied gases transportation and handling, as properties and basic information on liquefied gases, ship equipment and instrumentation, principles of gas carrier design, terminal equipment and instrumentation, the ship-shore interface, cargo measuring and control, cargo handling operations, emergency procedures and personal health-and-safety issues.
This publication has been initially established as the standard guide covering the operational side of the shipping industry; the book should be treated as the completely independent companion that is to be used in the course of the professional training for the operational qualifications. As it was a case with two previous editions of the textbook, it is dealing with the issues related to the safe handling of liquefied gases in bulk and emphasized the importance of proper understanding of physical characteristics of such cargoes with regard to the practical operation of the associated equipment on board vessels and at terminals. It is primarily intended to be used by the ship officers and other people bearing responsibility for the operations.
The purpose of the present SIGTTO publication is to provide a proper explanation of how insulation flanges protect from ignition caused by arcing. It contains information on the inductive circuits, electrical characteristics of the cargo transfer hoses together with the supporting calculations, some examples of the effects of hose inductance and resistance, information on the effect of capacitance, testing of the flanges and multiple loading arms and parallel circuits, all supplemented with the list of definitions and conclusions and recommendations.
The insulation flanges have been used for several decades; their effectiveness is sometimes seriously challenged, though there have been no reported fire incidents on the manifolds installed on board of tankers or gas carriers. This shall be taken into consideration by the ship operators having a background of road tanker operations, supplying the LNG as fuel oil.
Since this document mainly concentrates on the protection from arcing-caused fires, we would definitely consider it very important and recommended to everyone involved in such sort of operations as the info provided in the booklet might help in improving the operational safety.
The first introductory part of this SIGTTO-released document says that it has been written following numerous reports from the members of the present international organization, on the confusion and misunderstanding noticed between some ship and jetty operators; that is main reason why it has been released and please note that this document mainly pertains to terminals where rigid transfer arms are employed.
The principal objective of this report was to disconnect the arms in such a way that would totally eliminate the possible risks of release of the liquid and, in addition, reduce the release of the cargo vapor to the environment to a practically achievable minimum. In order to safely and timely conduct this operation, it is critically important that a good and carefully thought out procedure has been established and that the communication between people on board and on shore is reliable and permanent, since both of them carry the responsibility for safety during subject operation.
Among the most important aspects covered within this report there are drain system, isolation of valves, liquid removal, purging flammable vapors, verification, disconnection of the cargo manifolds etc. The annexes at the end provide case studies and example procedures...
Current LNG transportation practice provides for pressure relief systems, designed with credit for the tank's insulation in order to to prevent gas cargo pressurization due to boil-off and fire, as per IMO IGC Code 8.5. However, it is uncertain to what extent any insulation degradation, in a fire situation, is taken into account in the design of PRV systems.
As foam plastic insulation materials are subject to possible melting, degradation and/or ignition at temperatures lower than might be achieved during such fire exposure, there is concern that the PRV systems may not be capable of relieving the vapor flows that would result from the increased boil-off due to partial or total insulation failure. This SIGTTO publication covers following matters - the origins of the IGC Code, fire scenarios, LNG carrier pressure relief systems, simplified reapplication of the Code for loss of insulation, heat transfer into the tank; time based heat transfer, response of insulation materials to heat, and others.
This is quite useful document providing necessary updates required to be taken into account to organize the transportation, storage and handling of the LNG cargoes in a safe way.
This presentation by SIGTTO applies to the valves installed on board liquid petroleum gas vessels, but it can provide guidance to such valves on LPG terminals, as well. It is intended to serve as a supplemental guide to be used together with the relevant standards and codes for LPG valves and shall not override them.
In this book such an important issues as valve design, specific design consideration for ESD (emergency shutdown) valves, valve testing, material requirements and codes and standards, have been addressed. The publication is mostly intended to provide necessary technical guidance to the designers and/or operators on the applicable general requirements for valves for LPG service, designed for an operating temperature ranging between -55 and +80 degrees Celsius.
Though the document was specifically developed to apply to LPG vessels, the provisions contained in it may be equally applied throughout the liquefied petroleum gas industry. Note, however, that this paper shall not override any national/international standards or codes. The appendix at the last part of the document provides considerations to be taken into account during the periods of construction and maintenance.
The present Guide would mostly be applicable to all liquid gas carriers both at sea and approaches to the ports; it has been released by the working group with the assistance from members of OCIMF, ICS, SIGTTO and ISU aiming to provide a thorough reference that would be useful to the operating managements of gas ships in reviewing or developing their contingency planning.
The contingency plans supplement the SOPEP required for all ships >400 GT as per the Annex I to MARPOL. Regardless of how the liquefied gas is carried (pressure/temperature being meant), the cargo containment shall not be treated as part of the vessel's structure. Such containments are in all cases located inboard of the vessel's side plus above the bottom. The big portion of this booklet has been taken from the CPD (contingency planning document) that have been formulated by the managing teams of a number of companies within the shipping industry.
The present guide is mainly addressed at the ship operating companies and assumes some general understanding of the cargo characteristics as well as of the design, construction and, of course, operation of the gas carrying ships. Definitely useful publication not only to the managerial stuff but also all personnel.
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...