AD ALTA
JOURNAL OF INTERDISCIPLINARY RESEARCH
STRENGTH CHARACTERISTICS OF LNG TANKS AND THEIR APPLICATION IN INLAND
NAVIGATION
a
TOMAS KALINA,
b
MARTIN JURKOVIC,
c
MILAN
SAPIETA,
d
HELENA BINOVA,
e
ALZBETA SAPIETOVA
a
University of Zilina, Department of Water Transport,
Univerzitna 1, 010 26 Zilina, Slovakia
b
University of Zilina, Department of Water Transport,
Univerzitna 1, 010 26 Zilina, Slovakia
c
University of Zilina, Department of Applied Mechanics,
Univerzitna 1, 010 26 Zilina, Slovakia
d
CTU Prague, Department of Logistics and Management
Transport, Konviktska 20, Prague 110 00, Czech Republic
e
University of Zilina, Department of Applied Mechanics,
Univerzitna 1, 010 26 Zilina, Slovakia
email:
a
tomas.kalina@fpedas.uniza.sk,
b
martin.jurkovic@fpedas.uniza.sk,
c
milan.sapieta@fstroj.uniza.sk,
d
binova@fd.cvut.cz,
e
alzbeta.sapietova@fstroj.uniza.sk
Abstract: EU legislation in the field of transport and energy is focused on the safety of
transport and storage of LNG, environmental friendliness, but above all to protect the
health of the population. LNG is an important alternative to conventional ship fuel.
Under current IMO guidelines and ADN, LNG fuel tanks installed in the vessel must
meet the criteria of the LNG tank from a group of "independent types A, B, or C".
Specifically, the fuel tanks of inland waterway vessels are the type "C". One method
for determining the strength characteristics of the LNG is the tank finite element
method (FEM), which is evaluated using the HMH stress hypothesis. The result is a
set of the maximum stress characteristics and assessment of the suitability of LNG
tanks on inland vessels and floating terminals.
Keywords: LNG, LNG storage, strength characteristics, computation model, stress
tests
1 Introduction
Energy security and independence from fossil fuel imports from
Russia is one of the most frequent economic - political issues in
Central and Eastern Europe. Trade in strategic raw materials is
becoming an effective political tool for creating spheres of
influence in the regions, and thus a potential source of conflict.
One way to prevent this is to diversify sources.
Natural gas is the most used energy source after oil and black
coal. It is expected that its consumption will rise in the future.
Not only worldwide but also in the European Union. The
consumption of the natural gas in the world will drag the
emerging economies, mainly Asian countries. In the European
Union, it currently leads trend of "green" energy sources and
low-carbon fuels.
The most strategic of natural gas is the wide range of
applications. In addition to traditional technologies using natural
gas as a producer of the electricity and heat nowadays are here
new opportunities especially in transport. Increasingly stringent
standards aimed at emissions (mainly CO
2
, NO
x
, SO
x
), and
particulate matter (PM) from transport are forcing carriers to
look for the solutions to eliminate these negative aspects,
considering not only environmental but also economic aspects
(Tropp et al., 2012). In this regard, some of the most promising
solutions offer alternative fuel technology. Compared to
conventional fuels, liquefied natural gas (LNG) can reduce NO
x
by up to 85-90 %, SO
x
and PM by close to 100 % and CO
2
by
15-20 % (GIIGNL).
Road transport companies are faced with this problem for
decades. The first European emission standards Euro 1 took into
effect in 1993. Compliance with this standard required a
substantial change of engine elements such as installation
controlled three-way catalytic converter and lambda probe. In
comparison with the situation in 1993, currently applicable
emission standards Euro 6 have brought the reduction of PM by
99 % and NO
x
by 98 % (GIIGNL).
The first European legislative regulation concerning to the
emission limits for inland transport appeared in 2004. Directive
2004/26/EC complementing Directive 97/68/EC regulated
emissions of new engines installed on inland vessels for the
period until the end of 2008. Responding to developments in
road transport has brought further adjustments in the adjustment
of Directives 2010/26/EU and 2012/46/EU mainly focused on
modulating NO
x
emissions. The last legislative amendment was
approved by the European Parliament in July 2016. Within the
“phase V” Directive tightens emission limits for combustion
engines of non-road mobile machinery and also inland
navigation ships. These measures are accompanied by broader
support of the research in the field of alternative fuels. Inland
water transport clearly preferred the use of dual fuel systems
(diesel – LNG). Wider application of the LNG in transport
avoids the need for a functioning market (Barta et al, 2016). This
is related to the resolution of the many problems with logistics,
not only within the region but also with regard to the production
regions and physical properties related to LNG being transported
over long distances. It is necessary for solving the many
problems with the logistics, not only in the region of the
production, but also due to the other participating regions within
the logistics chain with respect to the physical properties of LNG
related to its transportation over long distances. Currently the
legislation applying to the transportation of dangerous goods
(ADR) allows using the LNG tankers on the inland waterways.
Tankers should be equipped with special containers - tanks for
the storage of cryogenic gases Similar tanks are also possible for
use for long-term storage in the central terminal. Although this
technology is not new, its application to inland vessels has only
just begun. During the designation and location of the containers
to an existing vessel the shape of the tank and the amount of
stored gas, as well as insulation and strength characteristics must
be considered (Sebor et al, 2006).
2 The legislative framework and the safety of transportation
and storage of LNG
Legislation in the field of transport, storage and distribution of
LNG in the world is different. The main idea is to ensure safety
in transportation and storage of LNG, environmental
friendliness, but especially health protection. Nowadays, in the
boom of implementation of LNG as an alternative fuel in the
transport and energy sectors in Europe, it is necessary to
implement safety risk assessment according to accepted
methodologies. European regulations mainly focus on the
outcomes regardless of the ways to achieve required level of
safety (GIIGNL).
EC (European Council) Directive 2012/18/ EU (SEVESO III) is
aimed at preventing accidents and prevention of conflicts of
transport of dangerous substances such as the LNG. The
directive was drawn up based on Council Directive 82/501/EEC
(SEVESO I) and EC Directive 96/82/EC (SEVESO II). On the
revision of SEVESO I and SEVESO II it was based on an
assessment of major accidents and analysis of the failure of
safety management systems for the transportation of LNG
(European Commission – SEVESO III).
European Committee for Standardization (CEN) defines codes
and regulations relating to import LNG:
European Union SEVESO III Directive 2012/18/ EU of 1
June 2012;
EN 1473: „Installation and equipment for LNG – Design of
onshore installations “. Designed for storage capacities
over 200 tones. This code is based on a risk assessment
approach;
EN 1160: „Installation and equipment for LNG – General
characteristics of LNG “;
EN 14620: „Design and manufacture of site built, vertical,
cylindrical, flat-bottomed steel tanks for the storage of
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