JPS6126720Y2 - - Google Patents

Description

[Detailed explanation of the idea] This invention relates to a low temperature tank with a dike.

For example, as a low-temperature tank for storing liquefied petroleum gas (LPG), etc., a cylindrical liquid barrier is provided around the cylindrical side wall of the tank, and an annular space is formed between them. Tank is known. In such a conventional cryogenic tank with a liquid barrier, a forced ventilation device is provided as a measure to prevent oxygen deficiency in the annular space, and this device is operated almost all the time. A liquid barrier is designed to contain all of the liquid that spills out due to brittle failure of a low-temperature tank and prevent it from leaking outside, but if a large amount of liquid spills out, the liquid barrier About 3 to 6 of the hydrostatic pressure to
A dynamic hydraulic pressure twice as large is applied, and this dynamic hydraulic pressure is greatest on the opposite side, 180 degrees away from the failure point of the cryotank, where the contents of the tank leak. For this reason, conventional low-temperature tanks with dikes require thick concrete dikes or embankments to be supported by embankments to withstand the large loads caused by leaked liquid. . In addition, there is a risk that the liquid leaked from the low-temperature tank into the annular space may become agitated and cause the liquid level to rise in some areas, and even if the leaked liquid becomes agitated, the liquid barrier will reliably prevent it from flowing outside. Therefore, the height of the dike will be quite high.

This idea was made in view of the above-mentioned circumstances, and it is possible to effectively utilize natural wind to ventilate the annular space between the tank side wall and the liquid barrier, and the liquid inside the tank can be kept at a low temperature. To provide a safe and economical low-temperature tank with a liquid barrier that can reduce the dynamic hydraulic pressure applied to the liquid dike when it flows out into the annular space, and can suppress the agitation of the leaked liquid and the resulting rise in liquid level. The purpose is to

The low-temperature tank with a liquid barrier according to this invention has a cylindrical liquid barrier installed around a cylindrical tank side wall, and an annular space is formed between the tank side wall and the liquid barrier. In the low-temperature tank, a partition cylinder is arranged in an annular space, and an annular ventilation passage communicating with each other at the lower part is formed between the partition cylinder and the tank side wall and between the partition cylinder and the dike, respectively. A plurality of partition plates extending vertically straight or diagonally are provided on at least one of the outer surface of the side wall and the inner surface of the liquid barrier to support the partition cylinder and partition off a portion of at least one of the annular ventilation channels except for the lower part. It is characterized in that a natural wind introduction opening is provided in the upper part of one of the two annular ventilation passages, and an exhaust opening is provided in the upper part of the other annular ventilation passage.

According to this invention, the natural wind introduced from the natural wind introduction opening is guided to the lower part of the annular space through one annular ventilation passage, and the air at the lower part of the annular space is used for exhaust through the other annular ventilation passage. It is discharged from the opening. Since at least one of the two annular ventilation paths is partitioned by a partition plate,
The ventilation effect of natural wind is enhanced, and as a result, the need for conventional forced ventilation equipment is eliminated, which not only saves energy, but also makes it easier to maintain and manage the low-temperature tank, improving safety. and,
Even when a forced ventilation system is installed for ventilation during periods of no wind, the ventilation capacity can be reduced.
Moreover, the driving time is short. In addition, due to the buffering effect of the partition plate, the dynamic hydraulic pressure applied to the liquid barrier when the content liquid flows out into the annular space due to brittle failure of the low temperature tank, etc., is reduced, and the agitation of the leaked liquid and the resulting liquid level The increase in height is also suppressed by the partition plate. This improves the safety of the dike,
In addition, it becomes possible to lower the height of the dike.

Embodiments of this invention will be described below with reference to the drawings.

In FIGS. 1 and 2, the cryogenic tank with a liquid barrier is installed on a base disk 1 fixed to the ground. The foundation disk 1 is supported on a large number of foundation piles (not shown) buried in the ground, and the lower part of the foundation disk 1 is underground and the upper part is above ground.
A bottom heating device (not shown) for freezing prevention is provided inside the base disk 1, and a common bottom plate 4 made of low-temperature steel or PS concrete is provided over the entire upper surface of the base disk 1. A cylindrical outer tank 5 is provided on the bottom plate 4, and a cylindrical inner tank 7 is provided inside the outer tank 5 with a cold insulator 6 interposed therebetween. As with conventional low-temperature tanks, the inner tank 7 serves as a primary container for the liquid content, and the outer tank 5 serves as a storage container for the cold insulating material 6.
A tank side wall 8 with a double shell structure is formed by the inner tank 7 side plate, the outer tank 5 side plate, and the cold insulation material 6 between them.
is formed.

A predetermined distance radially outward from the outer tank 5 (for example,
A cylindrical low-temperature steel liquid barrier (high-dike) 9 with an open top is provided on the outer peripheral edge of the common bottom plate 4, which is separated by approximately 1.5 to 5 m), and the outer tank 5 and liquid barrier 9 are connected to each other.
An annular space 10 is formed between the two. The liquid barrier 9 serves as a secondary container that stores all of the liquid contained therein and prevents it from flowing outside when the inner tank 7 is destroyed and the liquid inside flows out. Moreover, the liquid barrier 9 may be made of PS concrete.

A partition cylinder 1 extends within the annular space 10 from a position above the common bottom plate 4 to a position above the upper end of the liquid barrier 9 and below the upper end of the tank side wall 9.
1 is arranged, thereby forming annular ventilation passages 12 and 13 that communicate with each other at the lower part between the partition cylinder 11 and the tank side wall 8 and between the partition cylinder 11 and the liquid barrier 9, respectively. and,
A plurality of partition plates 14 are fixed to the outer surface of the tank side wall 8, that is, the outer surface of the outer tank 5, to support the partition cylinder 11 and partition the inner annular ventilation passage 12, and to the inner surface of the liquid barrier 9, the partition cylinder 11 is supported. At the same time, a plurality of partition plates 14 partition the outer annular ventilation passage 13.
is fixed. These partition plates 14 extend straight up and down over almost the entire height of the partition cylinder 11. A weather shield 15 is provided on the outer periphery of the top plate of the outer tank 5 and extends obliquely to above the partition cylinder 11, and an exhaust opening 16 is formed between the outer periphery of the weather shield 15 and the upper end of the partition cylinder 11. Further, a weather shield 17 is provided on the outer surface of the upper end of the partition cylinder 11 and extends diagonally outwardly through the upper part of the liquid barrier 9.
A plurality of struts 18 are provided between the middle part of the embankment and the upper end of the dike 9.
are provided, and the space between these supports 18 serves as an opening 19 for introducing natural wind. These weather shields 15 and 17 protect rain, snow, etc. from the annular space 1.
This is to prevent it from going to 0.

The annular space 10 is provided with a forced ventilation system (not shown) including a ventilation fan and a ventilation duct. This device is for ventilation when there is no wind, but it may not be necessary depending on the situation. Further, the ventilation capacity of this device may be smaller than that of conventional devices, and there is no need to operate it nearly all the time as in conventional devices.

In the above, the natural wind is the natural wind introduction opening 1.
9 into the outer annular ventilation passage 13 and further guided to the lower part of the annular space 10 by the partition plate 14. The air in the lower part of the annular space 10 flows upward in the inner annular ventilation passage 12 along the partition plate 14 and is discharged from the exhaust opening 16. In this way, the annular space 10 is divided into the inner and outer parts by the partition cylinder 11.
By partitioning into two annular ventilation passages 12, 13 and partitioning each ventilation passage 12, 13 with a partition plate 14, the annular space 10 can be effectively utilized to utilize natural wind.
Ventilation can be carried out. In addition, when the content liquid flows into the annular space 10 due to brittle fracture of the inner tank 7, the buffering effect of the partition plate 14 reduces the dynamic hydraulic pressure applied to the liquid barrier 9, and the inner tank 7
The agitation of the leaked liquid flowing out from the pipe and the rise in liquid level caused by this are suppressed. Further, even in the case where an aftershock occurs in a state where the liquid content has leaked into the annular space due to an earthquake, the partition plate 14 reduces the agitation of the leaked liquid and the resulting rise in the liquid level. Therefore, it is possible to make the height of the liquid barrier 9 lower than that of the conventional one.

The arrangement of the partition plate 14 is arbitrary.
may be provided only in the inner annular ventilation passage 12 as shown in FIG. 3, or may be provided only in the outer annular ventilation passage 13 as shown in FIG. Good too. In addition, when the liquid barrier 9 is made of steel and a partition plate is not provided on the inner surface as shown in FIG. 3, the liquid barrier 9 is A plurality of annular wind stiffeners are provided on the outer surface of the wind stiffener.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway side view showing one embodiment of this invention, Fig. 2 is a sectional view taken along the line shown in Fig. 1, and Fig. 3
4 and 4 are drawings corresponding to FIG. 2 showing two other embodiments of this invention, respectively. 8... Tank side wall, 9... Liquid barrier, 10... Annular space, 11... Partition cylinder, 12, 13... Annular ventilation passage, 14... Partition plate, 16... Exhaust opening,
19...Opening for introducing natural wind.

Claims (1)

[Scope of utility model registration request] In a low temperature tank with a liquid barrier, a cylindrical liquid barrier 9 is provided around a cylindrical tank side wall 8, and an annular space 10 is formed between the tank side wall 8 and the liquid barrier 9. A partition cylinder 11 is disposed within the tank 10, and annular ventilation passages 12 and 13 are formed between the partition cylinder 11 and the tank side wall 8 and between the partition cylinder 11 and the liquid barrier 9, which communicate with each other at the lower part. In order to support the partition cylinder 11 and partition off the lower part of at least one of the annular ventilation passages 12 and 13, a straight or vertical groove is formed on at least one of the outer surface of the tank side wall 8 and the inner surface of the liquid barrier 9. A plurality of diagonally extending partition plates 14 are fixed, and two annular ventilation passages 12,
Opening 1 for natural wind introduction at the top of either one of 13
9, and an exhaust opening 16 is provided in the upper part of the other.