JPH0331758Y2 - - Google Patents

Description

[Detailed description of the invention] "Industrial application field" This consideration relates to the improvement of liquid storage tanks for gasoline, oil, etc.

"Prior art and its problems" As is well known, in order to store gasoline, oil, etc. at gas stations, etc., it is necessary to store liquids in order to prevent the risk of fire and explosion of gasoline, etc., and to take into consideration the economy of installation space. Tanks are being buried underground. However, if the tank is buried underground, the steel plate of the tank may corrode due to moisture, groundwater, soil contents, etc., leading to leakage, which may contaminate the soil or well water. Therefore, when burying a liquid storage tank underground, it is recommended to cover the tank surface with asphalt to prevent corrosion and bury a vinyl detection tube with many holes drilled in it around the tank to detect liquid leaks. It may be taken. However, even with this method, corrosion cannot be completely prevented, and even if a liquid leaks, in order to find the leaking point in the tank, it is necessary to extract all oil etc. and dig around the tank again. It was also very time-consuming as it was necessary to remove the parts. In addition, it has been difficult to reliably detect liquid leaks because the detection tubes, such as vinyl tubes, become clogged with soil. In addition, to prevent tank corrosion, the tank has a double structure, and the space between the external tank and internal tank is filled with inert gas or non-oxidizing fluid, and leaks are detected by the pressure change of the filled material. A method was taken. When using this method, although it is possible to prevent corrosion of the internal tank and detect liquid leakage, there are similar problems such as corrosion of the external tank itself and the accompanying uncertainty in detecting leakage of enclosed materials. Moreover, there were technical and economical problems with regard to the sealing of the space between the external tank and the internal tank, injection of fillers, and ancillary equipment such as leakage detectors.

This idea was made in view of the above circumstances,
To provide an economical liquid storage tank which has a relatively simple structure, allows reliable liquid leakage and the detection of liquid leakage points.

"Means for Solving the Problems" The liquid storage tank according to this invention has a partition between the first compartment and the external tank, which is installed in an underground tank and is airtight with the inner wall of the tank. Two compartments are formed, and the first compartment has an internal tank with a gap between its outer bottom surface and the inner bottom surface of the external tank, and a fuel supply pipe etc. provided on the top surface of the internal tank. The inner bottom surface of the first compartment of the external tank is inclined downward toward the partition wall, and the ceiling of the second compartment is provided with the inner bottom surface of the first compartment of the external tank. A doorway is formed to allow people to enter and exit the second compartment, and a detection window through which the inside of the second compartment can be seen is formed in the partition wall.

"Example" An example of the liquid storage tank according to this invention will be described based on the drawings. Figure 1 shows the case where the liquid storage tank of this invention is buried underground. The external tank 1 is a cylindrical tank made of an iron plate, and is placed lying on a support (not shown) in a concrete structure 25 constructed at an appropriate depth underground. The inside of the external tank 1 is divided by a partition wall 3 into a first compartment 4 and a second compartment 5.

The partition wall 3 is made of an iron plate and the first compartment 4
The inner wall surface 1 of the external tank 1 is provided with airtightness to prevent liquid leakage between the inner wall surface 1 of the external tank 1 and the second compartment 5.
b, and at appropriate positions on this partition wall 3, there are circular shaped panels fitted with tempered glass, reinforced plastic, etc. for checking for leaks in the first compartment 4 and the internal tank 2. A detection window 6 is provided. Inside the first compartment 4, a cylindrical internal tank 2 made of an iron plate and having a smaller diameter than the external tank 1 lies horizontally, and a gap 9 is formed between it and the floor surface 4a of the first compartment 4. It is placed on the recess 7a of the support base 7. Anchor bolts 7b are embedded in the left and right parts of the support base 7, respectively, and the lower ends of tightening bands 8, 8 for fixing the internal tank 2 are connected to the anchor bolts 7b, respectively. . The floor surface 4a of the first compartment 4 is made of concrete, slopes downward in the longitudinal direction from the end opposite to the partition wall 3 toward the lower edge of the end wall 3, and is formed as a flat surface. A gap 9 is formed between the outer bottom surface 2a of the tank 2 and the floor surface 4a. In this case, the base of the support stand 7 is buried and fixed in the concrete floor, and the contact surface at the center of the support stand 7 and the floor surface 4a has a
A gap 7c is formed so that leaked oil and the like can flow (FIG. 2). A ventilation pipe 10 communicating with the interior of the internal tank 2 is provided on the upper surface of the body of the internal tank 2.
, a water removal pipe 11 for removing water accumulated at the bottom of the internal tank 2, a fuel supply pipe 12 for supplying oil, etc. in the internal tank 2, and displaying the amount of oil, etc. in the internal tank 2. an oil level gauge 13 for checking the inside of the internal tank 2, an extraction pipe 14 for taking out oil etc. from inside the internal tank 2, and an inspection manhole 15 for checking the inside of the internal tank 2.
are provided respectively. The lower ends of the vent pipe 10, water removal pipe 11, oil supply pipe 12, oil gauge 13, and extraction pipe 14 are fitted into sockets 16 as shown in FIG. 3, respectively, and face the inside of the internal tank 2. The vent pipe 10 connects to the external tank 1 through a socket 16a.
The vent hole 10a extends upward and extends above the ground. The water removal pipe 11 is connected to the socket 16b.
It is located in a storage chamber 18 provided in the surface concrete part 17 through which the external tank 1 is fitted, and a check valve 18b provided at the upper end of the dewatering pipe 18 is opened when the lid 18a that closes the storage chamber 18 is opened. A suction pump is connected to the inner tank 2 so that water accumulated at the bottom of the inner tank 2 can be taken out.
Further, the oil supply pipe 12 and the oil level gauge 13, like the water removal pipe 11, extend upward through the external tank 1 through sockets 16c and 16d, respectively, and are installed in storage provided in the surface concrete part 17. room 19
A lid body 1 that is located inside the storage chamber 19 and closes the storage chamber 19.
9a, connect the tank truck's refueling hose to the refueling port 12a of the refueling pipe 12, and connect the internal tank 2.
It is now possible to refuel inside. Further, the extraction pipe 14 is also connected to the socket 1 in the same way as the water removal pipe 11.
The external tank 1 is inserted through the external tank 6e and extends upward, and is located in a storage chamber 20 provided in the surface concrete part 17.Open the lid 20a that closes the storage chamber 20 and connect the extraction hose. Take-out pipe 14
The oil etc. stored in the internal tank 2 can be taken out by being connected to the take-out port 14a of the internal tank 2. Further, the above-mentioned inspection manhole 15 is inserted into the above-mentioned external tank 1 and is connected to the surface concrete part 17.
The inspection manhole 15 can be entered by opening a lid 21a that closes the storage chamber 21. Further, the second compartment 5 is formed in a size that at least a person can enter, and the ceiling 22 has an entrance/exit 23 through which a person can enter and exit the second compartment 5.
is provided. The entrance/exit 23 is located within a storage chamber 24 provided in the surface concrete portion 17, and the entrance/exit 23 can be entered by opening a lid 24a that closes the storage chamber 24.

A method for detecting liquid leakage from the liquid storage tank of the above embodiment and a method for using it will be explained. First, the lid 24a of the storage chamber 24 at the entrance/exit 23 of the second compartment 5 is opened, the user enters the second compartment 5 through the entrance/exit 23, and inspects the inside of the first compartment 4 through the detection window 6. When there is a liquid leak in the internal tank 2, the liquid leaking from the internal tank 2 falls onto the floor surface 4a of the first compartment 4, and the detection window passes over the floor surface 4a formed by sloping toward the partition wall 3. It flows to the 6th side. Therefore, liquid leakage in the internal tank 2 can be detected immediately and reliably through the detection window 6. In this case, a gap 7c is formed between the support base 7 of the internal tank 2 and the floor surface 4a, so that the flow of leaked liquid is not obstructed. In addition, the outer surface of the internal tank 2 can be seen through the detection window 6, and the floor surface 4a
Since it is possible to see the liquid leakage even before it flows to the detection window 6 side, it is possible to detect liquid leakage at an early stage. Furthermore, since the inner wall 1b of the external tank 1 can also be seen, corrosion of the external tank 1 can be inspected. Furthermore, since these tests are performed directly with the human eye, there is no chance of detector malfunction.
Detection of liquid leaks, etc. can be performed reliably. If a liquid leak from the internal tank 2 is discovered in this way, the stored liquid can be extracted from the take-out pipe 14 of the internal tank 2 and entered into the internal tank 2 through the inspection manhole 15 for inspection and repair. Therefore, there is no need to take the tank out to the surface, which saves time and effort.

Note that when the internal tank 2 is not inspected for liquid leakage, water is stored in the second compartment 5.
Since the partition wall 3 is airtightly welded to the inner wall surface 1b of the external tank 1, water will not leak into the first compartment 4. This stored water can also be used for disaster prevention or as drinking water in emergencies.
The compartment 5 can also be used as a water storage tank. Furthermore, even if water leaks and enters the first compartment 4, the water does not enter the internal tank 2, so the liquid stored in the internal tank 2 is not affected.

In the above embodiment, the floor surface 4a in the first compartment 4 is made of concrete, but it is not limited to this, and may be made of Alfalt or iron plate. If it is made of an iron plate, the part of the iron plate that the base of the support stand 7 of the internal tank 2 touches,
A cut having the same shape as the base is provided so that the base can fit into and out of the iron plate. Of course, the base of the support stand 7 may be placed on the floor surface 4a without being buried in the floor. Furthermore, although the floor surface 4a of the first compartment 4 was formed as an inclined flat surface, as shown in FIG. The entire floor surface may be formed to be inclined in the direction of the partition wall 3. In this way, the liquid leaking from the internal tank 2 gathers in the center of the floor surface 4a and flows toward the partition wall 3, so that liquid leakage can be detected more reliably. Alternatively, the detection window 6 may be provided with a door like a hatch on a ship to allow entry and exit, and may be formed with a gasket so as to be watertight when closed. In this way,
Enables entry and exit into the first compartment 4, detects liquid leakage,
It becomes easier to carry out repairs and the like more reliably. Note that the shapes of the external tank 1 and the internal tank 2 are not limited to cylindrical shapes either. Note that the external tank 1 may be covered with asphalt or the like and directly buried underground, instead of being housed in an underground concrete structure.

``Effect of the invention'' As explained above, the liquid storage tank of this invention has a first partition wall installed in an external tank buried underground, which is airtight with the inner wall surface of the tank.
A compartment and a second compartment are formed, and the first compartment has an internal tank with a gap between its outer bottom surface and the inner bottom surface of the external tank, and is provided on the top surface of the internal tank. The external tank is placed with a fuel supply pipe etc. exposed to the outside, and the inner bottom surface of the first compartment of the external tank is formed to be inclined toward the partition wall surface, and the second compartment is formed on the ceiling of the second compartment. Since the structure is such that an entrance is formed to allow people to enter and leave the compartment, and a detection window is formed in the partition wall to allow people to see into the first compartment, the structure is simple and does not require any incidental equipment. Since it is buried underground, it is economical because it makes effective use of land, and since the internal tank is housed within the external tank, there is no need to worry about corrosion of the internal tank. In addition, by entering the second compartment through the entrance/exit of the second compartment and observing the inside of the first compartment through the detection window, workers can not only directly inspect the internal tank for external abnormalities, but also detect liquid leaks in the internal tank. If this occurs, the leaked liquid should be
Since the liquid flows along the sloping floor of the compartment toward the partition wall where the detection window is located, even a small amount of liquid leakage can be reliably detected at an early stage. Since the inner wall surface of the external tank can also be observed at the same time, it is easy to inspect the external tank for corrosion, etc., and even if water floods into the first compartment from the outside through a corroded area, the water that has flooded along the slope will be removed. It is easy to discover because it flows. Additionally, since water can be stored in the second compartment, it can also be used as a drinking water storage tank for disaster prevention or emergencies.

[Brief explanation of drawings]

Figures 1 to 4 show an embodiment of this invention, with Figure 1 being a side view, Figure 2 being an end view, and Figure 3 being an end view.
The figure is an enlarged sectional view of the socket part, and FIG. 4 is an end view showing another embodiment of this invention. DESCRIPTION OF SYMBOLS 1... External tank, 1a... Inner bottom surface of external tank, 1b... Inner wall surface of external tank, 2... Internal tank, 3... Partition wall, 4... First compartment, 4a...
Floor surface, 5...Second compartment, 6...Detection window, 9...
Gap, 12...Oil supply pipe, 23...Entrance/exit.

Claims (1)

[Scope of utility model registration request] A first compartment and a second compartment are formed in an external tank buried underground by a partition wall provided to be airtight with the inner wall surface of the tank, and the first compartment has an internal tank. is placed with a gap between its outer bottom surface and the inner bottom surface of the external tank, and a fuel supply pipe, etc. provided on the top surface of the internal tank is exposed to the outside, and the inside of the first compartment of the external tank is The bottom surface is formed to be inclined downward toward the partition wall, and the ceiling of the second compartment is formed with an entrance that allows people to enter and exit the second compartment,
A liquid storage tank characterized in that the partition wall is formed with a detection window through which the inside of the first compartment can be seen.