JP2008019917A - Vertical double-shell cylindrical low-temperature storage - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vertical double-shell cylindrical low-temperature storage which widens the scope of application of a mounting place and realizes excellent stability, functionality and cost efficiency by forming the shape of an inner tank appropriately corresponding to conditions such as capacity and pressure of a storage and requested cold insulation performance and by allowing the height of the storage to be restricted low. <P>SOLUTION: The storage includes an inner tank (1) equipped with a hemispherical upper end plate (6) and a hemispherical lower end plate (8), and an outer tank (2) surrounding the inner tank (1) through a cold insulation layer (3). The inner tank (1) and outer tank (2) are supported on a base (5) by a cylindrical skirt (4) penetrating a bottom plate (12) end of the outer tank (2) to reach the inner tank (1). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vertical double-shell cylindrical low-temperature storage tank that stores low-temperature liquefied gas such as liquid nitrogen, liquid oxygen, and LNG.

A conventional vertical double-shell cylindrical low-temperature storage tank will be described based on Patent Document 1 (FIG. 3), Patent Document 2 (FIG. 4), and Patent Document 3 (FIG. 5).
In addition, the same symbol is attached | subjected to the same site | part.

The invention of the vertical double-shell cylindrical low-temperature storage tank of the conventional example 1 “outer tank support structure for vertical adiabatic low-temperature tank” Japanese Patent No. 3684318 (see Patent Document 1) will be described with reference to FIG.
As shown in FIG. 3 of the conventional example, the inner tank 1 includes a semi-elliptical upper end plate 6, a cylindrical intermediate body plate 7, and a semi-elliptical lower end plate 8. The outer tub 2 is formed by a dome-shaped outer tub roof plate 9, a cylindrical outer tub side plate 10, a conical trunk plate 11, and a horizontal disc-shaped outer tub bottom plate 12.

FIG. 4 shows the invention of the vertical double-shell cylindrical cryogenic storage tank of Conventional Example 2, “vertical double-shell cylindrical cryogenic storage tank” disclosed in Japanese Patent Application Laid-Open No. 2004-211759 (see Patent Document 2). Based on
As shown in FIG. 4 of the prior art, the invention of this patent document 2 “vertical double-shell cylindrical low-temperature storage tank” has a skirt 4 penetrating the outer tank 2 of the inner / outer tank double-shell storage tank, and the inner tank 1 and the outer tank. The tank 2 is supported on the foundation 5, the upper end plate 6 and the lower end plate 8 of the inner tank 1 are formed in a hemispherical shape, and the roof plate 9 of the outer tank 2 is formed in a dome shape.

As shown in FIGS. 3 and 4, the vertical double-shell cylindrical low-temperature storage tanks of Conventional Example 1 and Conventional Example 2 are each filled with a heat insulating material between the inner tank 1 and the outer tank 2. A cold insulation layer 3 is provided, and the inner tub 1 and the outer tub 2 are supported on a foundation 5 by a cylindrical skirt 4. Further, a center manhole 13 in the center, a roof sprinkler 14 for sprinkling water on the roof, a plurality of perlite manholes 15 for filling perlite between the inner and outer tubs, measurement, etc. Nozzle 16 and a roof handrail 17 are provided around the roof. Further, on the side surface of the outer tub 2, an elevating ladder 18 reaching the roof and a side watering device 19 for watering the side plate 10 are provided.

In addition, the vertical double-shell cylindrical low-temperature storage tank of Conventional Example 3 and the invention of “vertical double-shell cylindrical low-temperature storage tank” Japanese Patent Application No. 2006-049539 (see Patent Document 3) related to the present patent applicant are shown in FIG. 5 will be described.
As shown in FIG. 5, the patent document 3 “vertical double-shell cylindrical low-temperature storage tank” has an inner tank 1 and an outer tank 2 formed by a skirt 4 penetrating the outer tank 2 of the inner / outer tank double-shell storage tank. The upper end plate 6 and the lower end plate 8 of the inner tub 1 are supported on the base 5, and the roof plate 9 of the outer tub 2 is formed in a hemispherical shape concentric with the inner tub 1.

Japanese Patent No. 3684318 Japanese Patent Laid-Open No. 2004-211759 Japanese Patent Application No. 2006-049539

  In the invention of Patent Document 1 “Outer tub support structure for vertical insulated low temperature tank”, the upper end plate 6 and the lower end plate 8 of the inner tub 1 are formed in a semi-elliptical or dome shape as shown in FIG. Since the roof plate 9 of the outer tub 2 is formed in a dome shape, the end plates 6 and 8 and the roof plate 9 have to be thicker than the hemispherical one. In many cases, a lifting elevator 18 and a roof handrail 17 for maintenance are installed, and the structure is complicated and difficult to construct.

  In the invention of Patent Document 2 “Vertical Double-shell Cylindrical Low Temperature Storage Tank” of the present applicant, as shown in FIG. 4, the upper end plate 6 and the lower end plate 8 of the inner tank 1 are formed in a hemispherical shape. Therefore, these plate thicknesses can be reduced, and frost adhesion and dew condensation can be prevented in the outer surface in the vicinity of the connection portion between the skirt 4 and the conical trunk plate 11, but the roof plate 9 of the outer tub has a dome shape. Since it forms, the filling amount of the pearlite heat insulating material 3 between the roof part inner and outer tub became more necessary in the shoulder part.

Further, since the vertical double-shell cylindrical low-temperature storage tanks of the conventional example 1 and the conventional example 2 shown in FIGS. 3 and 4 both have a gentle dome shape, the outer tank roof plate 9 has a gentle dome shape. A plurality of perlite manholes 15 are required on the roof plate 9, and many accessories such as measurement nozzles 16 need to be provided, and a lifting ladder 18 extending from the ground foundation 5 to the outer tank roof plate 9, Maintenance accessories such as the roof handrail 17 were often installed.
Further, in addition to the roof watering device 14 for cooling, a side watering device 19 for directly watering the outer tank side plate 10 is necessary and large, and the shape changes complicatedly depending on the capacity and size of the storage tank. Equipment was required, and it took time and labor to build it.
And since there are many accessory equipment and a complicated outer peripheral shape with many protrusions, there was a concern that an unbalanced load might act on the storage tank due to wind and rain or snow.

  Further, in the invention of Patent Document 3 “Vertical Double Shell Cylindrical Low Temperature Storage Tank” of the present applicant, as shown in FIG. 5, the upper end plate 6 and the lower end plate 8 of the inner tank 1 are formed in a hemispherical shape. Therefore, it is possible to prevent the frost from adhering to the outer surface near the connecting portion between the skirt 4 and the conical body plate 11 and the occurrence of condensation, and the roof plate 9 of the outer tub 2 is formed in a hemispherical shape concentric with the inner tub 1. As a result, it is possible to reduce the number of accessories and equipment such as handrails on the outer tank roof, nozzles, side sprinklers, etc., and it has the great advantage that the plate thickness can be made thinner and lighter, but the overall storage tank becomes higher. Compared to the semi-elliptical end plate structure, the weld line of the hemispherical end plates 6 and 8 is longer, requiring much time for construction and inspection.

  The object of the present invention has been made in view of the problems of the prior art as described above, and has a shape of an inner tank that appropriately corresponds to conditions such as the capacity and pressure of the storage tank, the required cooling performance, and the storage tank. In addition, the vertical range of the installation location can be expanded, and in addition, a vertical double-shell cylindrical cryogenic storage tank excellent in stability, functionality and economy can be provided.

The vertical double-shell cylindrical low-temperature storage tank according to the invention of claim 1 is provided with an inner tank having a hemispherical upper end plate and a semi-elliptical lower end plate, and surrounds the inner tank through a cold insulation layer. An outer tub is provided, and the inner tub and the outer tub are supported on the foundation by a cylindrical skirt that penetrates the bottom plate end of the outer tub and reaches the inner tub.

The vertical double-shell cylindrical cryogenic storage tank according to the invention of claim 2 is provided with an inner tank provided with a semi-elliptical upper end plate and a hemispherical lower end plate, and surrounds the inner tank via a cold insulation layer. An outer tub is provided, and the inner tub and the outer tub are supported on the foundation by a cylindrical skirt that penetrates the bottom plate end of the outer tub and reaches the inner tub.

The vertical double-shell cylindrical low-temperature storage tank according to the invention of claim 1 is provided with an inner tank having a hemispherical upper end plate and a semi-elliptical lower end plate, and surrounds the inner tank through a cold insulation layer. Since the outer tub is provided and the inner tub and the outer tub are supported on the foundation by a cylindrical skirt that penetrates the bottom plate end of the outer tub and reaches the inner tub, the lower end plate of the inner tub has a semi-elliptical shape. For this reason, the height of the entire storage tank can be reduced as compared with a storage tank provided with a hemispherical lower end plate, and it can be applied to an area with severe height restrictions. The inner tank provided with the semi-elliptical lower end plate can be a storage tank having a structure more suitable for a low-pressure storage tank in which the thickness of the lower end plate is increased.

The vertical double-shell cylindrical cryogenic storage tank according to the invention of claim 2 is provided with an inner tank provided with a semi-elliptical upper end plate and a hemispherical lower end plate, and surrounds the inner tank via a cold insulation layer. Since the outer tub is provided and the inner tub and the outer tub are supported on the foundation by a cylindrical skirt that penetrates the bottom plate end of the outer tub and reaches the inner tub, the upper end plate of the inner tub has a semi-elliptical shape. Therefore, it is shorter than a storage tank with a hemispherical upper end plate, and the overall height of the storage tank can be reduced, making it possible to apply to areas with severe height restrictions. Due to the elliptical shape, the safety of work at height is improved. In addition, the lower end plate of the inner tub has a hemispherical shape and a longer support skirt, which prevents frost and condensation from forming on the outer surface near the connection between the skirt and conical body plate, and reduces heat conduction. Cooling condition is improved. Furthermore, since the connection part of the support skirt to the inner tank is positioned above and the distance from the mounting part to the center of gravity is reduced and stabilized, the storage tank is suitable for areas where earthquakes occur frequently. Since the inner tank provided with the hemispherical lower end plate is excellent in pressure resistance, it is a storage tank that is remarkably functional when applied to a high-pressure storage tank.

An embodiment of a vertical double-shell cylindrical cryogenic storage tank according to the present invention will be described with reference to FIGS.
FIG. 1 shows an overall longitudinal section of an embodiment of a vertical double-shell cylindrical low-temperature storage tank according to the invention of claim 1, and FIG. 2 shows a vertical double-shell cylindrical low-temperature storage tank according to the invention of claim 2. The whole longitudinal section of the example of an embodiment is shown.

As shown in FIG. 1, an inner tank 1 for storing a cryogenic liquid is provided, an outer tank 2 is provided so as to surround the inner tank 1, and a cold insulation layer 3 is provided between the inner tank 1 and the outer tank 2. .
The inner tub 1 is formed of a hemispherical upper end plate 6, a cylindrical intermediate body plate 7, and a semi-elliptical lower end plate 8.
The outer tub 2 includes a hemispherical outer tub roof plate 9 having the same center point as the upper end plate 6 of the inner tub 1, a cylindrical outer tub side plate 10, a conical trunk plate 11, a horizontal disk shape or the above It is formed with an outer tank bottom plate 12 having a gentle concave disk shape (not shown) having a curvature smaller than that of the lower end plate 8.
The cylindrical skirt 4 extends vertically downward from the lower end of the side surface of the inner tub 1, penetrates the end of the outer tub bottom plate 12 of the outer tub 2, and supports the inner tub 1 and the outer tub 2 on the foundation 5. .
Further, a center manhole 13 into which a heat insulating material can be charged is provided at the center of the top of the hemispherical outer tub roof plate 9, and a roof watering device 14 is arranged around the center manhole 13 in a ring shape.

As shown in FIG. 1, by forming the lower end plate 8 of the inner tub 1 in a semi-elliptical shape, the plate thickness is increased to improve the strength against liquid loads and external loads due to earthquakes, etc. Compared with the provided storage tank, the vertical width is narrow and the height is low, so that the height of the entire storage tank can be reduced, and it can be applied to areas with severe height restrictions.
Since the inner tank 1 having the semi-elliptical lower end plate 8 has a larger thickness than the storage tank provided with the hemispherical lower end plate, durability against an external load such as an earthquake is improved. It is functionally and economically superior, and has a structure suitable for low pressure storage tanks.
By forming the upper end plate 6 of the inner tub 1 in a hemispherical shape, a thin plate can be adopted because the internal pressure load and stress are equally applied to the plate surface, and this thin plate is used to press into a spherical shell shape with a constant curvature. Since the work can be manufactured with good workability and the load is reduced by adopting a thin plate, the load on the skirt 4 is reduced, and the reinforcing structure can be simplified in addition to the weight reduction.
Further, by forming the outer tub roof plate 9 in a hemispherical shape having the same center point as the upper end plate 6 of the inner tub 1, a thin plate is adopted and a spherical shell shape having a constant curvature is manufactured with good workability by press working. Since the load is reduced by the use of a thin plate, the load on the skirt 4 is reduced and the reinforcement structure can be simplified in addition to the weight reduction, and the load of snow and wind applied to the outer tank roof can be reduced. It becomes possible to reduce and to reduce the load burden to an outer tank reinforcement member and an outer tank support part.
Furthermore, the filling of the pearlite heat insulating material into the cold insulation layer 3 can be introduced in an average in the circumferential direction using the center manhole 13 at the center of the outer tub roof plate 9, so that a plurality of conventional pearlite manholes are provided. There is no need to install on the outer tank roof. When the heat insulating material is supplied from the center manhole 13, the cold insulation layer 3 in the roof portion is uniformly dispersed in a concentric circle, so that a blind spot that is not filled with pearlite grains from the periphery to the side portion is not formed.

  Although not shown, instead of the hemispherical outer tub roof plate 9 of FIG. 1, when a dome-shaped or semi-elliptical outer tub roof plate is adopted, it is a roof plate shape with little welding work. The safety of high-altitude work is improved, and the cold insulation performance is improved because the width of the cold insulation layer at the shoulder at the bottom of the outer tub roof is increased.

As shown in FIG. 2, an inner tank 1 for storing a cryogenic liquid is provided, an outer tank 2 is provided so as to surround the inner tank 1, and a cold insulation layer 3 is provided between the inner tank 1 and the outer tank 2. .
The inner tub 1 is formed of a semi-elliptical upper end plate 6, a cylindrical intermediate body plate 7, and a hemispherical lower end plate 8.
The outer tub 2 includes a semi-elliptical outer tub roof plate 9, a cylindrical outer tub side plate 10, a conical trunk plate 11, a horizontal disk shape, or a gentle concave disk having a smaller curvature than the lower end plate 8. It forms with the outer tank baseplate 12 of a shape (not shown).
The cylindrical skirt 4 extends vertically downward from the lower end of the side surface of the inner tub 1, penetrates the end of the outer tub bottom plate 12 of the outer tub 2, and supports the inner tub 1 and the outer tub 2 on the foundation 5. .
In addition, a center manhole 13 is provided at the center of the top of the semi-elliptical outer tub roof plate 9, and the intermediate shell plate 7 and the outer tub side plate 10 are disposed at appropriate positions on the outer periphery of the semi-elliptical outer tub roof plate 9. A plurality of pearlite manholes 15 for introducing a heat insulating material between them are provided.

As shown in FIG. 2, since the upper end plate 6 of the inner tank 1 is formed in a semi-elliptical shape, the vertical width is narrowed, so the height is lower than the storage tank provided with the hemispherical upper end plate, and the overall height of the storage tank is reduced. It can be lowered and can be applied to areas with severe height restrictions.
Since the upper end plate 6 of the inner tub 1 has a semi-elliptical shape with little welding work, the safety of work at high places is improved.
Further, since the lower end plate 8 of the inner tub 1 is hemispherical and has a longer support skirt portion, the amount of cooling heat transmitted from the skirt 4 to the outside is reduced, so that frost is formed on the outer surface near the connection portion between the skirt 4 and the conical trunk plate 11. Adhesion and condensation can be prevented, heat conduction is reduced, and the cold state is improved.
Furthermore, since the connection part to the inner tank 1 of the support skirt 4 is located above, and the distance from the attachment part to the center of gravity is reduced and stabilized, the storage tank is suitable for an earthquake-prone area. Since the inner tank 1 provided with the hemispherical lower end plate 8 is excellent in pressure resistance, the inner tank 1 has a structure suitable for a high-pressure storage tank.
Further, by forming the outer tub roof plate 9 in a semi-elliptical shape similar to the upper end plate 6 of the inner tub 1, the height of the storage tank is reduced and the cold insulation layer 3 of the roof portion filled with pearlite heat insulating material is formed. The width can also be made uniform.

Although not shown, instead of the semi-elliptical outer tub roof plate 9 of FIG. 2, when a semi-spherical or dome-shaped outer tub roof plate is employed, a thin plate is used and a sphere having a constant curvature is used. The shell shape can be manufactured with good workability, and the use of a thin plate reduces the load on the skirt. In addition to reducing the weight, the reinforcement structure can be simplified and the outer tank roof is loaded. It becomes possible to reduce the load of snow and wind, and to reduce the load burden to an outer tank reinforcement member and an outer tank support part.

As described above, the vertical double-shell cylindrical low-temperature storage tank illustrated in FIGS. 1 to 2 can reduce the height of the entire storage tank, stabilize the center of gravity, and increase the storage tank pressure from low to high. Accordingly, it is possible to select and apply in accordance with the cold insulation performance.
Further, as shown in FIGS. 1 and 2, the outer tank roof plate 9 is not provided with a roof corridor or a roof handrail, and the outer tank side plate 10 is not provided with a lifting ladder, thereby simplifying the structure. The outer tank roof plate 9 can be maintenance-free, and the outer tank roof plate 9 and the outer tank side plate 10 have no accessory facilities such as walkways, ladders, nozzles, etc., thereby reducing the uneven load and reducing this load. It is also possible to reduce the number of support members for supporting.
Moreover, since there are few protrusions in the outer tank roof board 9 and the outer tank side board 10, there is little wind resistance, there is also little corrosion by the retention of rainwater, and it is advantageous with respect to the load of snow.

The vertical double-shell cylindrical cryogenic storage tank according to the present invention adopts a combination of hemispherical and semi-elliptical end plates in accordance with the capacity, internal pressure, cold insulation performance, etc. of various cryogenic liquids. It is possible to provide a storage tank that is low in height and excellent in functionality and economy.

It is longitudinal cross-sectional explanatory drawing which shows the example of embodiment of the vertical-type double-shell cylindrical low temperature storage tank which concerns on invention of Claim 1. It is longitudinal cross-section explanatory drawing which shows the example of embodiment of the vertical double-shell cylindrical low temperature storage tank which concerns on invention of Claim 2. It is a longitudinal cross-sectional explanatory drawing which shows the vertical double-shell cylindrical low temperature storage tank of the prior art example 1. It is longitudinal cross-section explanatory drawing which shows the vertical double-shell cylindrical low temperature storage tank of the prior art example 2. It is a longitudinal cross-sectional explanatory drawing which shows the vertical double-shell cylindrical low temperature storage tank of the prior art example 3.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inner tank 2 Outer tank 3 Cooling layer 4 Skirt 5 Foundation 6 Upper end plate 7 Intermediate shell plate 8 Lower end plate 9 Outer tank roof plate 10 Outer tank side plate 11 Conical trunk plate 12 Outer tank bottom plate 13 Center manhole 14 Roof sprinkler 15 Perlite manhole 16 Nozzle 17 Roof handrail 18 Lifting ladder 19 Side watering device

Claims (2)

An inner tub provided with a hemispherical upper end plate and a semi-elliptical lower end plate is provided, an outer tub is provided surrounding the inner tub via a cold insulation layer, and an inner tub is penetrated through the bottom plate end of the outer tub. A vertical double-shell cylindrical low-temperature storage tank characterized in that the inner tank and the outer tank are supported on a foundation by a cylindrical skirt leading to An inner tub provided with a semi-elliptical upper end plate and a hemispherical lower end plate is provided, an outer tub is provided surrounding the inner tub via a cold insulation layer, and an inner tub is penetrated through the bottom plate end of the outer tub. A vertical double-shell cylindrical low-temperature storage tank characterized in that the inner tank and the outer tank are supported on a foundation by a cylindrical skirt leading to