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Managing Lng Risks

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  • 7/31/2019 Managing Lng Risks


    20052005 ioMosaic Corporation. All rights reserved. Updated August 2006 Page 1

    Man ag in g LNG Risk s:Separa t ing t h e Fact s

    f r om t h e My t h s

  • 7/31/2019 Managing Lng Risks


    20052005 ioMosaic Corporation. All rights reserved. Updated August 2006 Page 2

    A u t h o r s

    Dr. G. A. Melhem ([email protected]),

    Dr. A. S. Kalelkar ([email protected]),

    Dr. S. Saraf, ([email protected]),

    and Henry Ozog ([email protected])

    ioMosa ic Corpor a t ion Hous ton Of f ice

    2650 Fountain View Drive, Suite 410,

    Houston, Texas 77057

    Tel: 713-490-5220

    Fax: 832-553-7283

    ioMosa ic Corpor a t ion Headqu ar t ers

    93 Stiles Road,

    Salem, New Hampshire, 03079.

    Tel: 603-893-7009

    Fax: 603-251-8384

    Managing LNG Risks: Separa t ing t he Facts f rom th e Myths

  • 7/31/2019 Managing Lng Risks


    20052005 ioMosaic Corporation. All rights reserved. Updated August 2006 Page 3

    Facts and Myt hs

    Some parts of the US media have managed to dramatize key issues

    surrounding LNG transportation, facility operations, and proposed new

    projects. Erroneous media speculation and sensationalism, especially

    regarding the threat of terrorism, have created an atmosphere of anti-LNG

    sentiment fueled by fear and paranoia.

    The media are partly influenced by erroneous, so-called independent expert

    analysis and public statements. This has been exacerbated by political and

    public concerns and pressure, skepticism and doubts over recent studies

    and statements from LNG companies and government agencies, as well as

    historical and recent incidents such as Skikda.

    It is becoming very difficult for the average person to separate fact from

    fiction because of this sensationalism and the hidden motives and private

    agendas of various working groups.

    This paper will separate facts from myths regarding statements reported by

    various newspapers, working groups, and web sites.

    At t rac t iv eness o f LNG Fac i l i t ies and Vesse ls as

    Ter ro r i s t Targe ts

    After the terrorist attacks of 9/11, government agencies and the public

    became more concerned about chemical storage and transportation facilities

    that are close to populated areas. Facilities handling large quantities of

    hazardous materials, such as LNG terminals and tankers, were initially

    identified as attractive terrorist targets.

    The scenario feared by all involves a terrorist using an explosive charge (or

    flying an airplane) to breach and possibly detonate one or more storage

    tanks on a ship containing up to 125,000 m3 of LNG in a heavily populated

    area. The same scenario is feared for large LNG storage tanks. As a result,

    security and surveillance of LNG terminals/facilities and ships coming to port

    to unload LNG cargo have increased considerably.

    In 2002, the city of Boston denied permission to an LNG tanker from

    entering port and unloading its much needed LNG cargo at an Everett LNG

    terminal, during the winter. In addition, there is significant opposition to

    Er r oneous med i a

    specu la t i on and

    sensat iona l i sm,

    espec ia l l y regard in g

    t h e t h r e a t o f t e r r o r is m ,

    have c reated an

    a tm os pher e o f an t i -

    LNG sent im ent fue led

    by f ea r and pa r ano i a .

    LNG tank e r s and bu l k

    s to r age t ank s a r e no t

    a t t r ac t i v e t a r ge t s f o r

    t e r r o r i s t s wh o s eek t o ach ieve mass

    casual t ies .

    Managing LNG Risks: Separa t ing t he Facts f rom th e Myths

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    20052005 ioMosaic Corporation. All rights reserved. Updated August 2006 Page 4

    proposals for LNG terminal expansions, and as well as proposals to build

    new LNG terminals. The opposition comes from both the general public as

    well as politicians. There is a lot of debate surrounding the potential for an

    LNG explosion.

    Let us examine the issue of possible LNG explosion when the liquid and

    vapor are not confined. First, LNG has to be vaporized and then mixed in

    the right proportions with air in order to obtain a composition that can burn.

    Furthermore, methane is relatively insensitive to initiation as compared to

    heavier hydrocarbons. Available data and good understanding of explosion

    dynamics indicate that it is not possible to detonate LNG vapors, even with

    the use of an explosive charge (that is large enough) on a storage tank,

    unless the LNG vapors contain high fractions of ethane and propane (morethan 20%). Explosion test data on methane/ethane mixtures in the vapor

    phase support these statements1. The likelihood of this scenario is

    equivalent to each of the authors of this paper winning the power ball or

    megabucks lottery several times, simultaneously.

    The most likely outcome of a terrorist attack will be a large pool fire and

    possibly a low order deflagration/flash fire of finely divided LNG liquid

    droplets aerosolized by the blast force of the explosive charge. LNG pool fire

    hazards are localized and as a result thermal radiation effects (2nd degree

    burns) are typically confined to within one or two pool diameters from the

    edge of the flame. This significantly limits the extent of impact.

    As a result, LNG tankers and bulk storage tanks are not attractive targets

    for terrorists who seek to achieve mass casualties.

    Unders t and Hazards and Man age Risk

    If we only managed hazards, no one would be flying an airplane or driving a

    car to work. When we fly or drive we are aware that we could get killed but

    we factor in the likelihood of that occurring and it is very low. We should

    and do manage risk and not just hazards. The LNG industry has a lower riskprofile than airlines, and chemical and petrochemical processing facilities to

    name a few2. Risk is defined as the probability of occurrence of an unwanted

    event. Risk has two components, (1) a probabilistic one relating to the

    likelihood of occurrence of an event and (2) a deterministic one relating to

    the magnitude of the event.

    The l ik e l i hood o f t h i s

    scenar io i s equ iva lent

    t o eac h o f t he au tho r s

    o f t h i s paper w i nn i ng

    t he pow er ba l l o r

    m egabuc k s l o t t e r y

    severa l t imes ,

    s imul taneous ly .

    U l t i ma te l y , it i s a

    ques t i on o f wha t r i sk

    l eve l i s to le rab le or

    acceptab le vs . th e

    economic benef i t

    der i ved by soc ie ty /

    c ommun i t i es .

    1 Bull, D.C., and Elsworth, J.E., Susceptibility of Methane/ethane Mixtures to Gaseous Detonations in Air, Combustion and Flame, 35, 87

    91, 1979.

    2 Arthur D. Little Inc. and SAI Comparison of accident probabilities, 1975

    Managing LNG Risks: Separa t ing t he Facts f rom th e Myths

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    Ultimately, it is a question of what risk level is tolerable or acceptable vs.

    the economic benefit derived by society/communities.

    Whether the risk is perceived by society/individuals to be voluntary or

    involuntary, risk is also a key factor. The additional risk associated with

    smoking or driving a vehicle is a voluntary risk. Additional risk associated

    with siting of new facilities is usually considered involuntary risk that can

    only be avoided at a great cost, such as moving away from the area.

    Involuntary risk is much less tolerable/acceptable than voluntary risk.

    Communities are generally intolerant of activities that will be visually

    intrusive, noisy, produce offensive odors or are pollution threats. Where risk

    is concentrated in a local area, the potential impact of an accident will bevery visible and deeply felt. This is especially true when visible risk is

    contrasted with a road accident or disease where one or more isolated

    individuals are affected and there is negligible concentration of risk on


    Ironically, society in general will expand greater efforts to reduce visible

    risk despite the fact that more lives are lost by other causes.

    The magnitude of impact of a potential accident carries a lot of weight. An

    accident which has the potential (or is perceived to have the potential) to

    injure or kill a large number of people attracts more public interest than the

    individual incidents capable of killing or injuring the same number of people.

    The likelihood of a scenario leading to the total loss of containment involving

    an LNG tanker or a large LNG storage tank must be considered in

    conjunction with the potential hazards such events pose and their impact on

    the public. US regulations (49 CFR Part 193) require that LNG facilities have

    secondary containment for LNG tanks and LNG transfer facilities. In

    addition, the facility must maintain exclusion zones to protect the public

    from potential thermal radiation and flammable vapor dispersion hazards.

    Todays risk assessment methods can be used to establish individual and/or

    societal risk profiles or environmental impact. These methods are well

    understood and generally accepted by operating companies, the public, and



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