JPS59142982A - Double tank - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention forms an outer tank at an interval outside an inner tank, and a hole formed at the interval:! A pipe communicating between the two is attached to the outer tank, the space in A and the pipe are filled with liquid, and a liquid level indicator is installed at the tip of the pipe.
Related to heavy tanks.

Such a double tank has been proposed by the applicant in J:.

Generally, double tanks are buried underground and are used to store liquids such as oil or gasoline, and in such double tanks, if the inner tank is damaged or cracks, the inner tank Although the liquid stored in the FIB, such as oil, leaks out, it does not leak out from the outer tongue, and the liquid NUn does not cause any pollution. Furthermore, even if it leaks into the space, the amount of leakage is limited to the outer tank, and the level of the spilled liquid will not exceed the point where it is balanced with the level of the stored liquid in the inner tank. Since there is no leakage, the amount of outflow is small, and waste due to outflow of liquid can be avoided.

If the outer tank is damaged, groundwater will flow into the space between the inner and outer tanks, but will not flow into the inner tank. Therefore, from the viewpoint of safety measures and pollution problems in case of damage to the tank, a dual-vehicle tank is extremely preferable.

As mentioned above, in such a double tank, even if either the inner or outer tank is damaged, stored liquid or underground water will accumulate in the lower part of the space between the inner and outer tanks. Therefore, damage to the inner and outer tanks can be detected by detecting whether there is liquid in the space between the inner and outer tanks.

Naturally, there is a bottom at the bottom of the tank, so -
A part of the inner tank where liquid tends to accumulate cannot be seen from the outside. At the time of Shitak-C inspection, the inspection work is extremely troublesome, such as pressurizing the space between the inner and outer tanks and checking for changes in the JF force, or filling the tank with liquid and checking for changes in the liquid level.

Since this inspection work must be repeated over a certain period of time, a simple tank inspection method is required.
:.

In order to meet this request, Koto Kide, as previously mentioned,
We propose two small tanks in which leakage detection liquid is placed in the space between the inner and outer tanks, and damage to both the inner and outer tanks can be detected by changes in the level of the liquid.

According to the prior art, a liquid that does not freeze is used as the liquid for leak detection, for example, an ethylene glycol solution is used. However, the volumetric expansion rate of ethylene glycol solution due to temperature is about three times that of water, and it changes depending on humidity.In order to adjust the volume, the liquid level indicator becomes larger, and the displacement of the liquid due to temperature change and the internal and external tanks. The disadvantage was that it was difficult to distinguish between displacement due to leakage due to damage.

In this way, as a liquid for leak detection, there is antifreeze 1 (1), and there is no suitable liquid (1, 1) with a low expansion coefficient, and even if there is, the expensive one is practical and 4T.

Therefore, an object of the present invention is to provide a double tank in which the liquid to be placed in the space of the tank is set to 2'a, and the liquid is optimally filled depending on the position of the liquid to be covered.

According to the present invention, the liquid in the space inside and outside the tank has a heavy specific gravity, and a liquid level indicator is provided at the tip.1. : The liquid in this part is composed of a liquid with a light specific gravity.

The space between the inner and outer tanks is located deep in the ground 1Z, so
There is no need to worry about freezing, so there is no need to use antifreeze liquid. However, it is desirable that the liquid in the space has an anti-corrosion effect in order to prevent rust from forming on the inner and outer tanks. Since the liquid in this space is located below, a liquid with a heavy specific gravity is used.

On the other hand, since the liquid in the tube is located above, a liquid with a light specific gravity is used. It is preferable that the liquid in the pipe and the liquid in the space do not mix with each other. Since the liquid in the territory is located close to the earth's surface, it is desirable to use a liquid that does not freeze easily.

In the practice of the present invention, the liquid with a light specific gravity is preferably colored kerosene, and the liquid in the space is preferably 7T weak alkaline 7J water with a little bit of water sorter added to the water.

For example, buttons and streaks in concrete (weakly alkaline) will not rust. This shows that the slightly alkaline liquid has a rust-preventing effect.

A detailed description of the invention will be given below with reference to the drawings.

FIG. 1 shows the present invention implemented in a gas station,
A double tank, indicated as a whole by A, is buried underground and is constructed from an inner tank 1 and an outer tank 2. A number of spacers 3 are provided at intervals in the longitudinal direction, thus creating a space 4 between them. Since there is also a spacing in the direction, the space 4 communicates with the outer periphery of the inner tank 1.

A refueling machine 5 is installed on the ground, and refueling @ 6 connected to this refueling machine 5 is supplied from below inside the inner tank 1.
It extends downward, passes through the upper part of the inner tank 1 and the outer tank 2, and reaches the refueling machine 5. Furthermore, an oil supply pipe 7 is provided at the upper part of the inner tank 1 and extends upwardly through the outer tank 2.
-Aven I~Tube 8 is connected. Soshi-C oiling boat 7
and a manhole 9 in the rising part of the air vent pipe 8.
is provided. In the figure, 10 is a small office, 14 is a fire fence,
15 is a manhole. A communication pipe 11 communicates with the space 4 between the inner and outer tanks 1.2, and a liquid level indicator I3 of the detection liquid is connected to the upper end of the communication pipe 11.

According to the present invention, the space 4 between the inner and outer tanks 1.2 is filled with the first liquid It is filled with a second liquid Y that has a light specific gravity and is hard to freeze. During filling, it is preferable that the second liquid Y be positioned exactly at the lower end of the communication tube 11, that is, at the upper end of the space 4.

The first liquid X is preferably slightly alkaline water containing a small amount of caustic soda, and the second liquid is preferably colored kerosene.

Now, what about the details of liquid level indicator B? As shown in Figure i52,
The case 13 is attached to the upper end of the communication pipe 11 and has a frontage through which the communication pipe 11 opens, and has a transparent peephole 20 at the top of the case 13G and 1, and inside the case 13 is an inner case 21 with a transparent surface. is accommodated via the support column 22.

The bottom 25 of the inner case 21 is inside the inner case 21.
and a transparent spiral duplex 24 communicating with the upper part 20.
is accommodated, and the liquid Y moves up and down within the spiral tube 24 according to changes in the liquid level. . Since the second liquid Y is colored, a change in the liquid level is detected by a change in the diameter of the spiral tube 2/1 colored by the second liquid Y. In addition, as shown in FIG. 1, while the entire circumference of the inner tank 1 is covered with the outer tank 2, as shown in FIG.
The pipe 11 that carries the liquid level indicator B to the right may be connected to the space formed by both tanks so that only the outer tank 2 covers only the area around the tank except for the upper part of the tank.

As described above, in the present invention, the first liquid is filled in the space between the inner and outer tanks of the double tank, and the second liquid is filled in the pipe portion.
Since the liquid and the IC are made into separate liquids, the first liquid can be used as the one with the best rust prevention effect, and the second liquid can be used as the one that does not freeze. Selection becomes easy and leakage can be detected reliably.

[Brief explanation of drawings]

Fig. 1 is a partially sectional side view of an example of a filling station with a double tank to the right, in which the present invention is implemented, Fig. 2 is a sectional side view of a liquid level indicator implemented in the present invention, and Fig. 3 FIG. 2 is a side view, partially in section, of another embodiment of the two-car tank. A...Double tank 1...Inner tank 2...
Outer tank 3... Spacer 4... Space 11
...Communication pipe B...Liquid level indicator X...1st
Liquid Y...Second liquid Figure 1 Figure 2

Claims (1)

[Claims] forming an outer tank at intervals outside the inner tank;
A pipe that communicates with the space formed in the space is airtightly attached to the outer tank (the space and the pipe are filled with liquid, and a double tank with a liquid level indicator installed at the tip of the pipe) is attached airtight to the outer tank. Now, the liquid in the space has a heavy specific gravity, and the liquid in the pipe part (J) has a light specific gravity and is a liquid.
heavy tank.