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Providing environmentally friendly in-ground
LNG storage tanks renowned for their high-level of safety |
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LNG tanks are employed in a variety of types throughout the world according to social needs and the site environment. Storage tanks are broken down to two categories, in-ground storage tanks and above ground storage tanks.
In-ground storage tanks have a high level of safety and are environmentally friendly. Japan has 76 such tanks with a capacity of 6.3 million m3. Highly regarded overseas, Tokyo Gas constructed six tanks in Taiwan to hold 690,000 m3 and ten in Korea to hold 1.88 million m3. In 1970 the first in-ground LNG storage tank was constructed with a capacity of 10 thousand m3. Since then, Tokyo Gas has constructed 37 in-ground LNG storage tanks with a total capacity of 3.3 million m3, while working at improving tanks. Currently the company is constructing state of the art in-ground storage tanks including the world's largest underground storage tank with a capacity of 200,000 m3. Utilizing this technology and experience, Tokyo Gas is providing in-ground storage tanks suited to a variety of customer needs. |
Bird's-eye view of in-ground storage tanks
Bird's-eye view of underground storage tanks |
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How in-ground LNG storage tanks work: Part 1
Tank composition |
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Features of in-ground storage tank: Safety |
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In-ground LNG storage tanks are only partially visible from the outside
of the terminal site making them difficult to be targeted by terrorists.
Furthermore, since the LNG is stored below the ground surface, in the unlikely
event of a terrorist attack or the concrete roof being destroyed by a projectile,
the LNG would not leak onto the ground. Accordingly, the tanks are accredited
with the European standard EN1473, making them the safest way to store LNG.
In an earthquake the seismic motion is not amplified for in-ground storage tanks when compared to above-ground structures making them safer in earthquake-prone regions. In order to make the tanks much safer from terrorist attacks, tank roofs can be lined with reinforced concrete or the roof of the tanks can be completely underground. |
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Features of in-ground storage tank: Environmentally friendly |
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The roofs of in-ground LNG storage tanks are the only part visible from the surface making the tanks a difficult target for terrorists. Moreover the tanks are not obtrusive to the surrounding environment, reducing the psychological impact that large tanks usually arouse.
In a further developed type of the tank, Tokyo Gas has constructed a brand-new underground tank which are totally buried in the ground, at its Ohgishima LNG Terminal in Yokohama. The dome roof of the tank is covered with over one meter of earth making it completely invisible from the surface.
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Features of in-ground storage tank: Space-saving |
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In-ground storage tanks do not need to be surrounded by a dike and the legally required space between tanks as well as the necessary distance from items to be protected is relatively small allowing the tanks to conserve space.
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Construction costs and time |
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It is now possible to construct large capacity in-ground storage tanks
thanks to advances in technological development. Currently, Tokyo Gas
constructs in-ground storage tanks sized from several thousand cubic
meters to 200,000 cubic meters. Larger storage capacity makes for a lower per-unit
cost. In-ground storage tanks are constructed at roughly the same cost
as conventional above-ground storage tanks adding to the economical benefits.
Construction time is also relatively the same for in-ground storage tanks.
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List of Terminals (including under construction) |
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In Japan |
No. of Tanks |
Capacity (unit: cubic meter) |
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Negishi Terminal, Tokyo Gas |
12 |
10,000 - 200,000 |
Sodegaura Terminal, Tokyo Gas |
18 |
60,000 - 140,000 |
Ohgishima Terminal, Tokyo Gas |
4 |
60,000 - 200,000 |
Kofu Satellite Station, Tokyo Gas |
2 |
650 - 870 |
Hitachi Satellite Station, Tokyo Gas |
1 |
650 |
Shin-Minato Works, Sendai City Gas Bureau |
1 |
80,000 |
Sodeshi Terminal, Shimizu LNG |
2 |
82,900 - 94,300 |
Chita LNG Terminal, Chita LNG |
1 |
160,000 |
Chita Midorihama Works, Toho Gas |
1 |
200,000 |
Senboku Terminal, Osaka Gas |
1 |
45,000 |
Fukuoka Terminal, Saibu Gas |
2 |
35,000 |
Kumamoto Satellite Station, Saibu Gas |
1 |
2,000 |
Nagasaki Terminal, Saibu Gas |
1 |
35,000 |
Sodegarua Thermal Power Station, Tokyo Electric Power |
9 |
60,000 - 90, 000 |
Higashi-Receiving Terminal, Tokyo Electric Power |
9 |
60,000 |
Futtsu Receiving Terminal, Tokyo Electric Power |
11 |
90,000 - 125,000 |
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Overseas |
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Yung An Terminal, CPC |
6 |
100,000 - 130,000 |
Incheon Terminal, KOGAS |
10 |
140,000 - 200,000 |
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