JPH0781279B2 - LNG receiving base system and LNG shipping base system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an LNG receiving base system and an LNG shipping base system.

[0002]

2. Description of the Related Art Natural gas, which is a clean energy and has an important position as a fuel for power generation and a raw material for city gas,
In Japan, most of them depend on imports from overseas, and in the producing countries they are liquefied and transported as liquefied natural gas (LNG) by sea to Japan by LNG vessels, and are received at the receiving terminal and vaporized for use. .

LNG has a low temperature of about -160 ° C., and pipes that have been subjected to a high degree of heat insulation treatment are required for pipe transportation.
Since long-distance LNG transportation is not economical, LNG receiving bases are usually installed adjacent to the thermal power plants and the supply bases of large city gas companies on the coast where LNG ships can enter.

By the way, the LNG import project is difficult to be realized in a small amount in terms of the liquefaction cost in the natural gas producing country, the marine transportation cost, and the vaporization cost in the receiving terminal, and the LNG receiving amount and the consuming amount are consumed. Due to the relationship, the optimum scale is decided by itself, and the LN currently operating all over the world.
The majority of G ships have a loading capacity of 120,000 to 130,000 M ^{3 and} outside.

The water depth of the berth of the LNG carrier of this loading capacity is at least about 12 m, and it is relatively close to the big city where electricity and city gas are demanded, and there is a large-scale site on which the land facilities of the receiving terminal can be installed. The beaches obtained are generally shallow and L
It is often difficult to berth an LNG vessel alongside the quay of an NG receiving terminal. In addition, even if the coast is filled up to the depth of deep water, the landfill cost will be incurred, and the dredging cost will be incurred when the LNG ship is directly dredged on the quay.
Moreover, huge amount of money is required for retaining the quay, which is not economical.

[0006] Therefore, at an LNG receiving terminal located on a shallow coast, a jetty that is generally long at a right angle from the quay of the terminal is projected offshore, and an LNG ship is pierged near the tip of the jetty parallel to the jetty. Or, mooring equipment such as dolphins was installed on the sea so that the LNG carrier could be moored in a T-shape to the pier, and a loading arm for unloading LNG from the moored LNG carrier was installed at the pier or its tip. It is installed on the platform, and LNG piping is installed from this to the LNG storage tank so that LNG can be received in the LNG storage tank.

The LNG storage tank at the LNG receiving terminal for receiving LNG imported by an ocean-going LNG carrier has a large capacity and is a low temperature / low pressure storage tank. Conventionally, a metal double shell flat bottom whose structure is shown in FIG. 4 is shown. The vertical cylindrical storage tank 1 with a spherical roof or the membrane type semi-underground storage tank 2 shown in FIG. 5 is exclusively used.

The former LNG storage tank 1 is constructed by providing a cold insulation layer 13 between an inner tank 11 made of a low temperature resistant metal material and an outer tank 12 made of a metal material for room temperature, and on the ground surface 14. Is installed.

In the latter LNG storage tank 2, most of the depth of the storage tank is below the ground surface 21, and the side portion is the concrete side wall 2.
2 is formed by stacking a cold insulation layer 23 and a metal membrane 24 on the inner side, and the bottom part has almost the same configuration. The roof is made by suspending a suspension deck 27 from a dome-shaped steel roof 25 with a suspension rod 26, and keeping the cold insulation on it. It is constructed by providing a layer 28.

Since the constructions of these storage tanks are well known, further explanation will be omitted. However, as shown in FIGS. 6 and 7, these storage tanks are installed on the land portion of the receiving terminal. The site for that purpose occupies more than half of the area of the base. In the case of the base using the above-ground tank shown in Fig. 6, it suffices to construct the ground and hit the pile up to the support layer to build the storage tank 1 on top of it, but in case of an accident, it is necessary to use the adjacent storage tank or other equipment. Maintaining a legal separation distance between the property and the borderline between neighboring areas and surrounding security properties, and enclosing a storage tank to form a breakwater 1
4 must be provided. Further, in the example of the base provided with the semi-underground tank 2 shown in FIG. 7, since the liquid level in the storage tank is below the upper surface of the surrounding embankment 29 (see FIG. 5), the liquid barrier is not necessary. Legal separation is required and the storage tank and its surrounding area is limited in its use for other purposes.

The receiving terminals shown in FIGS. 6 and 7 are both LNG.
Storage tank 1 or 2, LNG treatment equipment 3 such as LNG vaporization equipment, mooring equipment 5 for LNG vessels 4 installed offshore offshore of the base, and platform for unloading LNG from LNG vessels 4 moored at this mooring equipment. 6, a loading arm 7 and a pier 8 connecting the platform 6 and the base land area. 6 and 7, the mooring equipment 5 is drawn at a position close to the land shore due to space limitations, but the pier 8 may extend from several hundred meters to several kilometers on a shallow coast.
L unloaded from LNG ship by loading arm 7
The NG is transported to the onshore LNG storage tank 1 or 2 by the LNG piping laid endlessly on the jetty 8. The cost of constructing the pier 8 is extremely high, but in addition to the L
The construction cost of NG piping is also high.

As described above, the conventional LNG receiving terminal requires a large space for installing a storage tank, and when constructing the receiving terminal on the coast near a large city with a high land price, the land price is extremely high. In addition, when the mooring position of the LNG ship is provided away from the coast on a shallow beach, the cost of the jetty and the LNG receiving piping laid on the jetty is extremely high.

The LNG unloading terminal in a natural gas producing country is a natural gas liquefaction facility, an LNG storage tank for storing LNG liquefied by this facility, an LNG ship mooring facility, and an LNG tank moored to an LNG ship moored at this mooring facility. When the LNG ship mooring equipment is offshore from the base, an LNG delivery pipe is provided on the pier extending from the onshore base to the loading arm to load the LNG in the LNG storage tank to the LNG ship. Therefore, for the construction cost of the jetty and the LNG piping laid on it,
The same problems as at the receiving terminal will occur.

[0014]

SUMMARY OF THE INVENTION The present invention is a conventional LN.
In consideration of the above-mentioned difficulties of the G receiving terminal and the shipping terminal, the area required for the receiving terminal is small, and the area is shallow and L
The first problem is to provide an LNG receiving terminal system that eliminates the need for a jetty and LNG receiving piping laid on the pier even when the mooring positions of NG ships are installed offshore. L at the LNG shipping base
A second object is to provide an LNG shipping base system that does not cost the pier from the land and the LNG loading pipe when the mooring equipment of the NG ship is installed offshore.

[0015]

[Means for Solving the Problems] The structure of the first invention for solving the above-mentioned first problem is an LNG treatment facility such as an LNG vaporization facility provided at an onshore portion of an LNG receiving terminal on the coast, and the above-mentioned onshore facility. Mooring equipment for mooring LNG vessels installed offshore some parts of the sea, LN from LNG vessels moored to the mooring equipment
Unloading means for unloading G, L unloaded by the unloading means
LNG storage tank for storing NG, LN from the above-mentioned unloading means
In an LNG receiving terminal system having a receiving pipe for transferring LNG to a G storage tank and a discharging pipe for discharging LNG to the LNG processing equipment, the LNG storage tank is located below the LNG receiving base on the sea floor and near the mooring equipment. It is constructed as a tunnel type underground buried type storage tank that extends to the bottom.
On the offshore side of the NG storage tank, rising from the top surface of the storage tank to the sea,
An airtight caisson is installed between the receiving pipe and the LNG storage tank, and the land side underground portion of the LNG storage tank rises from the upper surface of the storage tank to the ground and houses the dispensing pipe and the like inside. A vertical shaft is provided between the LNG storage tank and the LNG storage tank.

Further, the structure of the second invention for solving the above-mentioned second problem is a natural gas liquefaction facility provided at an onshore portion of an LNG shipping base on the coast, and an LNG liquefied by the natural gas liquefaction facility. LNG storage tank for storing LNG, a receiving pipe for transferring LNG from the liquefaction facility to the LNG storage tank, a mooring facility for mooring an LNG ship on the offshore sea of the land area, and an LNG vessel for mooring the LNG ship moored at the mooring facility. In the LNG shipping terminal system having a loading means and a delivery pipe for transferring LNG from the LNG storage tank to the loading means, the LNG storage tank extends from the underground of the LNG shipping base land area to the seabed near the mooring facility. The LNG storage tank is constructed as an underground buried storage tank, and on the offshore side of the LNG storage tank, the LNG storage tank rises above the storage tank to the sea and accommodates the above-mentioned dispensing pipes and the like. Bath and caisson is provided with airtightness between, on the land side underground portion of the LNG storage tank to accommodate rising up ground from 該貯 tank top, the receiving piping LNG
A vertical shaft having airtightness is provided between the storage tank and the storage tank.

[0017]

In the receiving base system of the first aspect of the invention, L
LN unloaded from NG ship by unloading means by LNG ship
G is an LN installed in a caisson that rises from the upper surface of the storage tank to the sea near the end of the offshore side of a tunnel-type underground storage tank that extends from the underground part on the base side of the base to the bottom of the sea near the mooring facility offshore.
It is received and stored in the storage tank through the G receiving pipe. The stored LNG is delivered to the onshore LNG treatment facility at the base via a delivery pipe installed on the land side of the LNG storage tank in a vertical shaft rising from the upper surface of the storage tank to the ground.

With the above construction, the jetty from the land part of the base to the offshore mooring facility and the LNG receiving pipe laid on it are not required, and the LNG receiving pipe is added to the water depth at the point where the mooring facility is installed to add a little length. The construction cost is low and the construction period can be shortened.

Since the LNG storage tank is buried in a tunnel form below the sea floor above the sea above the land, the area required for the LNG storage on the land of the LNG receiving terminal is only for the conventional storage on land. Compared to the case where it is installed, it will be buried deep underground in a tunnel type, so it is highly safe against accidents of storage tanks and the upper surface of it can be used for other purposes such as playgrounds. It is possible. The tunnel used as a storage tank can be easily excavated in a short period of time using a shield machine.

Also in the case of the LNG shipping base system of the second invention, similarly, the jetty from the land to the mooring position of the LNG ship and the LNG shipping pipes laid on it are unnecessary. Also, L
Since the NG storage tank is completely buried underground and there is no roof above the ground, it can be said that the NG storage tank is safer than the conventional storage tank system.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below in detail with reference to the drawings, mainly regarding an LNG receiving base system.

FIG. 1 is a perspective view showing the concept of the construction of an embodiment of an LNG receiving terminal system according to the present invention, and FIG. 2 is a sectional view showing its LNG storage tank and its receiving / delivering portion.

The LNG storage tank is the land portion 30 of the LNG receiving base.
It is a tunnel type underground buried storage tank 31 which extends from the underground to the bottom of the sea near the platform 6 where the loading arm 7 at the center of the mooring equipment 5 of the offshore LNG ship 4 is installed. In this embodiment, Two units are provided in parallel. The LNG receiving terminal onshore unit 30 is provided with an LNG ground facility 32 such as an LNG vaporizing facility on the ground.

A caisson 33 rising up from the upper surface of the storage tank to the sea is erected near the end of the LNG storage tank 31 on the offshore side, and the LNG loaded by the loading arm 7 is placed inside the caisson 33.
The LNG receiving pipe 34 for transferring the gas to the LNG storage tank 31, the return gas pipe for returning the gas generated by vaporization in the storage tank to the LNG ship, and the like are accommodated.

On the other hand, in the vicinity of the land side end of the LNG storage tank 31, a vertical shaft 35 is erected from the upper surface of the LNG storage tank 31 to the ground. A discharge pipe 36 including a pump barrel is housed in the vertical shaft 35.

Therefore, the jetty which has been conventionally extended from the land portion of the LNG receiving terminal to the platform 6 and the LNG receiving pipe laid on the jetty are unnecessary.

It should be noted that FIGS. 1 and 2 show an example, and the tunnel type underground storage tank can be extended further on both the sea side / land side than these drawings. Therefore, the caisson and vertical shaft are not always near the end of the storage tank.

A cross section of the LNG storage tank 31 is shown in FIG. L
For excavation of the tunnel 40 serving as an NG storage tank, a shield machine itself for excavating a subway or a railway tunnel, or a machine having a similar diameter to the excavable diameter, can be used.

Similar to a railroad tunnel, a concrete segment 41 is filled on the inner surface of the tunnel 40 excavated by the shield machine, and a concrete lining 42, a heat insulating material layer 43, and a metal membrane 44 are provided inside the segment 41.
Are laminated in this order. A heating pipe 45 is embedded near the outside of the inside of the concrete lining 42, and a heat medium is caused to flow in the heating pipe to prevent the soil surrounding the LNG storage tank 31 from freezing.

Since this LNG receiving terminal system is constructed as described above, the LNG unloaded from the LNG ship 4 moored by the offshore mooring equipment 5 by the loading arm 7 is It is received in the LNG storage tank 31 via the LNG receiving pipe 34 provided in the caisson 33. The LNG stored in the LNG storage tank 31 is the delivery pipe 3 including the pump barrel housed in the vertical shaft 35.
It is delivered to the LNG ground equipment 32 via 6.

Excavation of the tunnel by the shield machine is
Compared with a series of construction work such as construction of the ground for construction of the above-ground type or semi-underground type storage tank, placement of sheet pile, etc., the work efficiency is excellent and reliable storage tank construction work can be done in a short period of time. Combined with the fact that the pier up to the LNG ship mooring equipment and the LNG piping work on it will not be required, the construction period can be shortened.

In addition, the construction cost is greatly reduced due to the fact that the site for installing the LNG storage tank is small and the jetty and the LNG piping on it are unnecessary.

The embodiment of the first invention for the LNG receiving base system has been described above. The LNG ground facility 3 shown in FIG.
2 is a natural gas liquefaction facility, and a discharge pipe 36 in the vertical shaft 35
Can be read as the receiving pipe, and the receiving pipe 34 in the caisson 33 can be read as the payout pipe, whereby the second invention of the LNG shipping base system can be realized.

Also in this case, it can be expected that the construction period for excavating the storage tunnel will be shortened, and the construction cost will be reduced because the jetty and the LNG piping on the jetty will not be required.

[0035]

As described above, according to the present invention, the pier from the land portion of the LNG receiving terminal system and the LNG shipping terminal system to the mooring equipment of the LNG ship and the LNG piping on the pier are unnecessary, and the land portion Since the site area for the LNG storage tank is small, it is effective in reducing the construction cost of the base. Also, the LNG storage tank is a tunnel type underground buried type that can be excavated by a shield machine with good work efficiency, and the pier Also, combined with the fact that the LNG piping on it is not necessary, the effect of shortening the construction period can be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view including a partial cross section showing a concept of a configuration of an LNG receiving base system according to the present invention.

FIG. 2 is a vertical sectional view including a center line of the LNG storage tank.

FIG. 3 is a cross-sectional view showing the configuration of the LNG storage tank.

FIG. 4 is a cross-sectional view showing a schematic configuration of a known double-shell flat-bottomed vertical cylindrical LNG storage tank.

FIG. 5 is a sectional view showing a schematic configuration of a known membrane-type semi-underground type LNG storage tank.

FIG. 6 is a perspective view showing a concept of a conventional LNG receiving terminal using a double shell flat bottom vertical cylindrical LNG storage tank.

FIG. 7 is a perspective view showing the concept of a conventional LNG receiving terminal using a membrane type semi-underground type LNG storage tank.

[Explanation of symbols]

4 LNG carrier 5 Mooring equipment 6 Platform 7 Loading arm (unloading equipment, loading equipment) 30 LNG receiving terminal land area 31 Tunnel type LNG underground storage tank 32 LNG aboveground equipment (natural gas liquefaction equipment of shipping terminal system) 33 Caisson 34 Receiving piping (Delivery piping for shipping base system) 35 Vertical shaft 36 Delivery pipe (receiving piping for shipping base system) 40 Tunnel 41 Segment 42 Concrete lining 43 Thermal insulation layer 44 Membrane

Claims (4)

[Claims] 1. An LNG treatment facility such as an LNG vaporization facility provided onshore at an onshore LNG receiving terminal, a mooring facility for mooring an LNG ship provided offshore of the land, and an LNG moored at the mooring facility. Unloading means for unloading LNG from a ship, LN for storing LNG unloaded by the unloading means
In an LNG receiving terminal system having a G storage tank, a receiving pipe for transferring LNG from the unloading means to the LNG storage tank, and a discharging pipe for discharging LNG to the LNG processing facility, the LNG storage tank is a land part of the LNG receiving terminal onshore. It is configured as a tunnel-type underground buried type storage tank that extends from the underground to the bottom of the sea near the mooring facility. On the offshore side of the LNG storage tank, it rises from the top surface of the storage tank to the sea and accommodates the receiving pipes, An airtight caisson is provided between the LNG storage tank and the land side underground portion of the LNG storage tank, which rises from the upper surface of the storage tank to the ground and accommodates the dispensing pipes and the like inside.
An LNG receiving terminal system, characterized in that a vertical shaft having airtightness is provided between the storage tank and the storage tank. 2. The LNG receiving terminal system according to claim 2, wherein the LNG storage tank is configured by laminating a concrete segment, a concrete lining, a heat insulating material layer, and a metal membrane in this order on the inner surface of the underground tunnel. . 3. The LNG receiving terminal system according to claim 3, wherein a heating pipe is embedded in the concrete lining. 4. A natural gas liquefaction facility provided onshore at an LNG shipping base on the coast, an LNG storage tank for storing LNG liquefied by the natural gas liquefaction facility, and an LNG from the liquefaction facility.
A receiving pipe for transferring LNG to an NG storage tank, a mooring facility for mooring an LNG ship provided offshore of the land, a loading means for loading LNG on an LNG ship moored at the mooring facility, and the above-mentioned load from the LNG storage tank In the LNG shipping terminal system having a delivery pipe for transferring LNG to the means, the LNG storage tank is configured as a tunnel-type underground underground storage tank extending from the underground of the LNG shipping base onshore to the seabed near the mooring equipment. On the offshore side of the LNG storage tank, there is provided a caisson that rises from the upper surface of the storage tank to the sea and houses the above-mentioned payout pipe and the like and has airtightness with the LNG storage tank. The LNG has a vertical shaft that rises from the upper surface of the storage tank to the ground, accommodates the receiving pipes and the like, and has airtightness with the LNG storage tank. Load base system.