JPH0144590B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a bellows-shaped water-enclosed oil storage tank that is provided with a closed oil storage tank that is vertically expandable and retractable while being surrounded by water within the tank body.

[Prior art and its problems] Conventional cylindrical tanks for storing petroleum are classified by roof type into fixed roof type and floating roof type.These two types of tanks each have the following: There are problems such as.

1. Fixed roof type (1) A ventilation valve is installed on the roof, which allows oil to be taken in and taken out and breathes due to changes in outside temperature, resulting in large vapor loss from stored oil.
Also, pollution is caused by vapor emissions.

(2) When discharging oil, vapor gas may mix with the atmosphere that entered through the vent valve, causing explosive gas to fill the tank, which is dangerous.

(3) In general, the construction cost of a fixed roof is relatively high, and the assembly period is relatively long. For this reason, it is not used in large tanks.

2. Floating roof type Although this type has improved the various drawbacks of the above-mentioned fixed roof type, it still has the following problems.

(1) There is a problem with the structural mechanism of the weather hood that prevents rainwater from entering between the outer circumference of the floating roof and the side panels of the tank, and although many improvements have been made to solve this problem, there is still no technology to completely prevent rainwater from entering. has not been established.

(2) The sealing mechanism between the tank side plate and the pontoon also has the same problem as (1) above.

(3) Although there is less danger from flames than with fixed types, there is still the problem of so-called rim flames between the pontoon and side plate.

(4) Although vapor loss is significantly improved compared to the fixed type, work loss occurs due to evaporation of oil adhering to the side panels when the floating roof is raised and lowered.

Furthermore, problems common to both include corrosion of the bottom plate, damage near the annular plate due to uneven ground subsidence or earthquakes, oil leakage out of the tank due to sloshing during earthquakes, and the resulting flame generation. There is a problem.

This invention was made in view of the above-mentioned circumstances, and its purpose is to provide a bellows-shaped water storage tank that eliminates vapor loss and improves fire resistance, earthquake resistance, and weather resistance. This is what I am trying to do.

[Means for Solving the Problems] The bellows-shaped encased water oil storage tank of the present invention includes a sealed oil storage tank having a bellows-shaped side wall that expands and contracts in the vertical direction while being guided by a guide pole in the top-open tank body. A space was provided between the tank and the inner wall, and an oil injection and discharge pipe was connected to the bottom end of the tank, and water was poured into the space to surround the tank on all four sides. It is characterized by this.

[Function] (1) Since the oil is stored in a sealed oil storage tank and there is no vapor breathing effect, vapor loss can be completely eliminated. Therefore, there is no problem of pollution due to vapor discharge, and there is no risk of explosion due to mixing of vapor and air.

(2) Because the reservoir is completely surrounded by water, it is extremely resistant to fire spread and self-ignition.

(3) Since the oil storage tank is completely surrounded by water, which is heavier than oil, even if the oil storage tank should be damaged, the oil will only float to the surface within the tank body and will not leak out of the tank. Furthermore, even if the tank itself is damaged due to an earthquake, only water will flow out, and there is no risk of fire. In the event that the tank body and oil storage tank are damaged at the same time, the first thing that will flow out is water, and by the time the oil starts to flow out, it is necessary to take measures such as transferring the oil to another tank to prevent the oil from flowing out. can be prevented.

(4) There is no need to install a weather hood seal, which is a problem with floating roof tanks, and there is no need to consider rainwater at all. Furthermore, there is no problem even if the surface of the water freezes in cold regions.

(5) It is also effective against sloshing during earthquakes because a considerable portion of the horizontal force acting on oil storage is absorbed by the expansion and contraction of the bellows-shaped side walls.

[Example] An example of the present invention will be described below with reference to FIGS. 1 and 2. In the figure, 1 is a steel tank body with an open top, consisting of a bottom plate 2 and side plates 3, and is installed on a foundation mound or concrete slab 4. 5 is a water supply pipe provided at the lower end of the tank body 1 and has a stop valve 5a. Reference numeral 6 denotes a sealed oil storage tank provided in the tank body 1 with a space between it and the inner wall of the main body 1, and has a bellows-shaped side wall 6 made of waterproof synthetic fiber or rubber material that expands and contracts in the vertical direction.
A bottom portion 6b made of the same material as the side wall 6a or a steel plate is watertightly joined to the lower end portion of the side wall 6a using an adhesive or the like, and a top lid made of the same material as the bottom portion 6b that slopes upward toward the center is attached to the upper end portion of the side wall 6a. 6c are watertightly joined. Reference numeral 7 denotes a cross-sectional annular support member that supports the oil storage tank 6 welded to the bottom 2 of the tank body 1. The oil storage tank 6 is fixed to the upper flange of the support member 7 by welding or the like.
7a is a water hole W provided in the web of the support member 7;
It is a communication hole. Reference numeral 8 denotes a pipe for injecting and discharging oil L that opens at the bottom 6b of the oil storage tank 6, and the penetrating portion of the support member 7 and the side plate 1 is made watertight. Reference numeral 9 denotes a guide pole erected on a support stand 10 which also serves to support the bottom 6b of the oil storage tank 6, and its upper end is fixed to the center of a cross-shaped beam 11 extending over the upper end of the tank body 1. Reference numeral 12 denotes a guide member fixed to the center of the upper lid 6c of the oil storage tank 6, which is connected to the guide pole 9.
It is installed watertightly and swingably against the
The oil storage tank 6 is guided by this guide pole 9 and expands and contracts in the vertical direction. Reference numeral 9a denotes a stopper fixed to the upper end of the guide pole 9 to restrict the extension of the oil tank 6. Reference numeral 13 denotes an air vent valve provided near the center of the upper lid 6c.

When filling oil L into this oil storage tank for the first time, open the air vent valve 13 provided on the upper lid 6c of the oil storage tank 6, and then open the air vent valve 13 provided on the upper lid 6c of the oil storage tank 6.
At the same time, water W is fed into the tank body 1 from the water supply pipe 5, and the oil L is injected so that the oil level inside the oil storage tank 6 and the water level outside the oil storage tank 6 are almost the same. and water W is supplied. As a result, the oil pressure and the hydraulic pressure due to the liquid level acting on the inside and outside of the bellows-shaped side wall 6a of the oil storage tank 6 are almost balanced, so that it is possible to prevent unreasonable force from acting on the bellows-shaped side wall 6a. When the oil L is injected into the oil storage tank 6 until it reaches its upper limit as shown in FIG. 1, the supply of the oil L is stopped and the air vent valve 13 is closed. Then, only water W is further fed until it covers the upper lid 6c of the oil storage tank 6 as shown in FIG. 1, and after the oil storage tank 6 is completely surrounded by water W, the valve 5a of the water supply pipe 5 is closed. In this way, the final filling of oil L is completed. Next, when the stored oil L is discharged, the valve 5a of the water supply pipe 5 is kept closed, the water W is not discharged, and only the oil L is discharged. As the oil L is discharged, the oil storage tank 6 gradually shortens, and the height of the water W above the upper lid 6c increases slightly. From the second time onwards, the oil L can be stored in a state where the oil storage tank 6 is completely surrounded by the poured water W by simply putting in and taking out the oil L.

Note that the tank body 1 is not limited to being made of steel plate, but may be made of concrete, or may be of an underground type. The water surrounding the oil storage tank is not limited to water, but may be any liquid that is nonflammable and heavier than oil.

[Effects of the Invention] The bellows-shaped water oil storage tank of the present invention is as described above, and has the following effects.

(1) Since the oil is stored in a sealed oil storage tank and there is no vapor breathing effect, vapor loss can be completely eliminated. Therefore, there is no problem of pollution due to vapor discharge, and there is no risk of explosion due to mixing of vapor and air.

(2) Because the reservoir is completely surrounded by water, it is extremely resistant to fire spread and self-ignition.

(3) Since the oil storage layer is completely surrounded by water, which is heavier than oil, even if the oil storage tank were to break, the oil would simply float on top of the water within the tank body and would not leak out of the tank. do not have. Furthermore, even if the tank itself is damaged due to an earthquake, only water will flow out, and there is no risk of fire. In the event that the tank body and oil storage tank are damaged at the same time, the first thing that will flow out is water, and by the time the oil starts to flow out, it is necessary to take measures such as transferring the oil to another tank to prevent the oil from flowing out. can be prevented.

(4) There is no need to install weathered seals, which is a problem with floating roof tanks, and there is no need to consider rainwater at all. Furthermore, there is no problem even if the surface of the water freezes in cold regions.

(5) It is also effective against sloshing during earthquakes because a considerable portion of the horizontal force acting on oil storage is absorbed by the expansion and contraction of the bellows-shaped side walls.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention;
FIG. 2 is a plan view of FIG. 1. 1...tank body, 6... sealed oil storage tank, 6a...
...Accordion-shaped side wall, 8...Oil injection and discharge pipe, 9...Guide pole, L...Oil, W...Water.

Claims (1)

[Claims] 1. A closed oil storage tank having a bellows-shaped side wall that expands and contracts in the vertical direction guided by guide poles is provided in the tank main body with an open top, with a gap between it and the inner wall of the main body, and an oil tank is installed at the lower end of the tank main body. 1. A bellows-shaped water-enclosed oil storage tank, characterized in that an injection/discharge pipe is connected thereto, and water is injected into the space between the two to surround the oil storage tank on all four sides.