JP2004083244A - High pressure gas storage facility - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely detect leakage of high pressure gas stored in a reservoir in high pressure gas storage facilities constructed in a rock mass and to detect the leakage of the high pressure gas stored in the reservoir even in cases where a little amount of gas is present in a drainage body or no groundwater is present. <P>SOLUTION: The outer circumference of the reservoir 7 is covered with the drainage body 8 and the drainage body 8 is connected to a gas quantity measuring instrument 9 and a gas detecting tube 10 via a connecting pipe 11. The gas detecting tube 10 is connected to a gas detector 12 by connecting pipe (not shown). The gas detector 12 is provided in a top part tunnel provided in the upper part of a cavity part 1, on the ground surface, or in an access tunnel 2 connected from the reservoir 7 to the ground surface. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a high-pressure gas storage facility that stores high-pressure gas in a storage tank installed in rock or ground.
[0002]
[Prior art]
As is well known, a high-pressure gas storage facility has recently been realized in which a cavity formed in a rock or ground is used as a storage tank for storing a high-pressure gas such as natural gas. This high-pressure gas storage facility covers the inner wall of a cavity formed in the rock or ground with a lining material, and interposes a backfill material between the inner wall and the lining material to form a space inside the lining material. This is a facility that uses as a storage tank for storing high-pressure gas. Such a facility is effective in that it can safely store a large amount of high-pressure gas and does not impair the landscape on the ground.
[0003]
Meanwhile, in the high-pressure gas storage facility as described above, in order to safely store the high-pressure gas for a long period of time, it is necessary to detect the leakage of the high-pressure gas stored in the storage tank to the outside. Therefore, conventionally, the periphery of the storage tank is covered with a drain pipe having a plurality of holes formed in the whole, and the plurality of drain pipes are connected to a gas collection pipe provided on an upper outer periphery of the storage tank. Further, this gas collection pipe is connected to a gas discharge pipe provided inside a top tunnel formed above the storage tank. As described above, the leakage of the high-pressure gas is detected by measuring the pressure inside the drainage system constituted by the drainage pipe, the gas collection pipe, and the gas discharge pipe. In other words, in a high-pressure gas storage facility equipped with this drainage system, the inside of the drainage pipe is usually filled with groundwater. After collecting, it reaches the gas exhaust pipe and is discharged to the outside. The change in pressure in the drain pipe at this time is grasped, and leakage of the high-pressure gas stored in the storage tank to the outside is detected.
[0004]
[Problems to be solved by the invention]
However, the conventional method as described above has the following problems. First, when even a small amount of gas is present in the drain pipe, the change in pressure in the drain pipe cannot be accurately grasped, so that the accuracy of leak detection decreases. In addition, especially when there is no groundwater, the drain pipe is not filled with water, and the accuracy of the leak detection of the high-pressure gas stored in the storage tank by the pressure measurement is extremely reduced. Gas detection was not possible.
[0005]
The present invention has been made in consideration of the above-described problems, and reliably detects leakage of high-pressure gas stored in a storage tank, and when a small amount of gas exists in a drain pipe or when groundwater is discharged. An object of the present invention is to detect leakage of high-pressure gas stored in a storage tank even when it does not exist.
[0006]
[Means for Solving the Problems]
The high-pressure gas storage facility according to claim 1, wherein the inner wall of the cavity formed in the rock or ground is covered with a lining material, and a backfill material is interposed between the inner wall and the lining material. A high-pressure gas storage facility using a space inside the lining material as a storage tank for storing high-pressure gas,
A drain body arranged between the inner wall and the backfill material and formed by a drain pipe having a plurality of holes on an outer peripheral surface, connected to the drain body via a connection pipe, and collected by the drain body And a gas detector for analyzing a component of the gas to be analyzed.
[0007]
With such a feature, when a leak of the high-pressure gas stored in the storage tank occurs, the leaked gas enters the drainage body through the drain pipe and reaches the gas detector via the connection pipe. With this gas detector, the gas component in the drainage body is directly measured.
[0008]
The high-pressure gas storage facility according to claim 2 is the high-pressure gas storage facility according to claim 1, wherein the gas detector is provided above the cavity, and is provided inside a top tunnel connected to the cavity. It is characterized by being provided.
[0009]
With such a feature, when the drainage body is filled with water, the leaked gas rises in the drainage body by buoyancy and reaches the gas detector via the connection pipe. If the drainage body is not filled with water, the leaked gas rises in the drainage body and reaches the gas detector via the connection pipe.
[0010]
The high-pressure gas storage facility according to claim 3 is the high-pressure gas storage facility according to claim 1, wherein the gas detector is provided above a boring hole provided from the cavity to the surface of the ground. It is characterized by:
[0011]
With such a feature, even without a top tunnel, it is measured directly by the gas detector. When the drainage body is filled with water, the leaked gas rises in the drainage body by buoyancy and reaches the gas detector via the connection pipe. Furthermore, even when the drainage body is not filled with water, the leaked gas rises in the drainage body and reaches the gas detector via the connection pipe.
[0012]
The high-pressure gas storage facility according to claim 4 is the high-pressure gas storage facility according to claim 1, wherein the gas detector is connected to the cavity and extends obliquely upward to an inside of an access tunnel reaching the ground surface. It is characterized by being provided.
[0013]
With such a feature, when the drainage body is not filled with water, it is measured directly by the gas detection means, even without a top tunnel or a borehole. If the drainage body is not filled with water, the leaked gas flows through the drainage body and reaches the gas detector via the connection pipe.
[0014]
The high-pressure gas storage facility according to claim 5, which is the high-pressure gas storage facility according to any one of claims 1 to 4, wherein the gas measuring the amount of gas collected by the drainage body in addition to the gas detector. It is characterized by having a quantity measuring device.
[0015]
With such a feature, when the high-pressure gas stored in the storage tank leaks, the flow rate is measured in addition to the component analysis of the leaked gas collected by the drainage body.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, first, second, and third embodiments of the high-pressure gas storage facility according to the present invention will be described with reference to the drawings.
[0017]
<First Embodiment>
First Embodiment A high-pressure gas storage facility according to a first embodiment of the present invention will be described. In the present embodiment, a high-pressure gas storage facility is constructed in a bedrock A where groundwater exists.
[0018]
As shown in FIG. 1, a hollow portion 1 is formed by excavating a bedrock A. The cavity 1 is connected to the ground via an access tunnel 2. The access tunnel 2 is configured such that an upper access tunnel 2a connected to an upper portion of the hollow portion 1 and a lower access tunnel 2b connected to a lower portion of the hollow portion 1 merge on the way. Above the cavity 1, a top tunnel 3 is formed in the rock A, and the cavity 1 and the top tunnel 3 are connected via a shaft 4. The top tunnel 3 is connected to the access tunnel 2.
[0019]
The inner wall 1 a of the cavity 1 in the bedrock A is covered with a lining material 5. A concrete backfill material 6 is interposed between the lining material 5 and the inner wall 1a of the cavity 1. The space inside the lining material 5 is used as a storage tank 7 for storing high-pressure gas such as natural gas.
[0020]
Drainage bodies 8 are arranged between the inner wall 1 a of the cavity 1 and the backfill material 6. As shown in FIG. 3, the drainage body 8 is stretched in a mesh shape over the entire outer peripheral surface of the backfill material 6. As shown in FIG. 2A, the drainage body 8 includes a plurality of drainage pipes 8a, a first water collection pipe 8b, a second water collection pipe 8c, and a connection socket 8d. The drainage pipe 8a is formed of a short hollow pipe having a modularized shape and a plurality of holes for taking in groundwater on the outer peripheral surface. In the present embodiment, a mesh pipe whose peripheral surface is generally formed in a mesh shape is used for the drain pipe 8a, but is not limited to this, and is shown in FIG. 2 (b). As shown in FIG. 2 (c), a net-like pipe formed by fixing a net material to the inner peripheral surface of a helically shaped core material and forming a tubular shape, or a plurality of rings arranged in parallel as shown in FIG. Any tube having a structure having a plurality of holes on the peripheral surface, such as a tube having a high pressure resistance and integrally formed into a tube by braiding a linear core material, may be used. In addition, the first water collecting pipe 8b and the second water collecting pipe 8c are formed of a hollow pipe such as a steel pipe or a vinyl chloride pipe connected to the connecting pipe 11 from the drain pipe 8a. The first water collecting pipe 8b is arranged along the inner wall 1a of the vertical cavity 1 so as to connect the vicinity of the top and the bottom of the storage tank 7 and has a certain angle when viewed from the top of the storage tank 7. Are spaced apart from each other. The second water collection pipe 8c is arranged along the inner wall 1a of the horizontal cavity 1 so as to be orthogonal to the first water collection pipe 8b, and a plurality of the second water collection pipes are arranged at predetermined intervals in the vertical direction. ing. The connection socket 8d is used for the purpose of connecting the plurality of drainage pipes 8a or the drainage pipe 8a with the first water collection pipe 8b and the second water collection pipe 8c in a state of communicating with each other. As shown in FIG. 3, the drainage body 8 having such a configuration is stretched in a mesh pattern over the entire outer peripheral surface of the backfill material 6.
[0021]
As shown in FIG. 1, the connection between the upper part of the drainage body 8 and the gas amount measuring device 9 and the gas detection pipe 10 installed in the top tunnel 3 are branched in the horizontal direction and the vertical direction in the top tunnel 3. Each is connected via a pipe 11. The gas amount measuring device 9 is connected to an end portion of a connection pipe 11 branched in a horizontal direction, and the gas detection tube 10 is connected to an upper end portion of the connection pipe 11 branched in a vertical direction in an upright state. The gas detection tube 10 is a cylindrical member having a scale for measuring a gas amount on a side portion and a closed upper end, and is connected to the gas detector 12 via a connection tube (not shown). I have. The gas detector 12 is installed in the top tunnel 3 and has a function of performing gas component analysis. A pressure gauge 13 is connected to the connection pipe 11 branched in the horizontal direction.
[0022]
A gas discharge pipe 14 is connected to the gas amount measuring device 9. The gas discharge pipe 14 is piped from the inside of the top tunnel 3 to the inside of the access tunnel 2 to the surface of the ground. Further, a gas discharge valve 15 is provided at an end of the gas discharge pipe 14 on the gas amount measuring device 9 side. This gas discharge valve 15 is normally closed.
[0023]
The lower part of the drainage body 8 is connected to a water collecting pipe 16 provided in the lower access tunnel 2b. A drain valve 17 is interposed in the water collecting pipe 16, and the tip of the water collecting pipe 16 is connected to a water collecting pit 18 installed in the lower access tunnel 2b. Further, a drain pipe 19 is provided from the water collecting pit 18 through the access tunnel 2 to the ground surface. The drainage pipe 19 is provided with a drainage pump 20.
[0024]
Next, in the high-pressure gas storage facility having the above-described configuration, a method of detecting when the high-pressure gas stored in the storage tank 6 has leaked will be described.
[0025]
The high-pressure gas is stored in the storage tank 7 which is airtight by the lining material 5 and the backfill material 6. The groundwater contained in the bedrock A enters through the drain pipe 8a, and the inside of the drain body 8, the connection pipe 11, and the gas detection pipe 10 is filled with water.
[0026]
When the high-pressure gas stored in the storage tank 7 leaks, the leaked high-pressure gas (hereinafter referred to as “leakage gas”) enters the drainage body 8 through the drain pipe 8a and rises due to the buoyancy of the leaked gas. This leaked gas rises from the inside of the drainage body 8 to the inside of the gas detection pipe 10 via the inside of the connection pipe 11. Thereby, gas accumulation occurs in the gas detection tube 10 which is normally filled with water. The amount of the leaked gas accumulated in the gas detection tube 10 is measured by a scale attached to the gas detection tube, and the component of the leaked gas accumulated in the gas detection tube 10 is analyzed by the gas detector 12. I do. This makes it possible to determine whether or not the high-pressure gas stored in the storage tank 7 has leaked. Further, by performing the gas component analysis by the gas detector 12 at a predetermined time every day, it is possible to know the presence or absence of leakage on a daily basis.
[0027]
When the leakage of the high-pressure gas stored in the storage tank 7 further progresses and a large amount of leakage gas is generated, the gas discharge valve 15 is opened and the leakage gas is discharged from the connection pipe 11 through the gas amount measuring device 9. The gas enters the pipe 14 and is discharged to the outside through the gas discharge port 14a. At this time, the flow rate of the gas discharged outside is measured by the gas amount measuring device 9. Thereby, the amount of the released leaked gas can be grasped.
[0028]
<Second embodiment>
A second embodiment of the high-pressure gas storage facility according to the present invention will be described. Note that, in this embodiment, the same components as those used in the first embodiment are denoted by the same components, and description thereof is omitted.
[0029]
As shown in FIG. 4, the boring hole 21 is provided vertically from the upper portion of the cavity 1 to the surface of the ground. Above the borehole 21, the gas detector 12 is installed. The upper part of the drainage body 8 and the gas detector 12 are connected via a connection pipe 11 a provided in the borehole 21. A gas discharge pipe 14 in which a gas discharge valve 15 is interposed is connected to the head of the connection pipe 11a.
[0030]
Next, a description will be given of a method of detecting a case where the high-pressure gas stored in the storage tank 7 leaks in the high-pressure gas storage facility having the above-described configuration.
[0031]
When the high-pressure gas stored in the storage tank 7 leaks, the leaked gas enters the drainage body 8 through the drain pipe 8a and rises due to the buoyancy of the leaked gas. This leaked gas rises from the inside of the drainage body 8 to the gas detector 12 via the inside of the connection pipe 11a. The gas detector 12 performs a gas component analysis of the leaked gas that has risen. This makes it possible to determine whether or not the high-pressure gas stored in the storage tank 7 has leaked.
[0032]
<Third embodiment>
A third embodiment of the high-pressure gas storage facility according to the present invention will be described. Note that, in the present embodiment, the same components as those used in the first and second embodiments are denoted by the same components, and description thereof is omitted. In this embodiment, a high-pressure gas storage facility is constructed in a bedrock B where no groundwater exists.
[0033]
As shown in FIG. 5, the upper part of the drainage body 8 and the gas discharge valve 15 provided in the upper access tunnel 2a are connected via a connection pipe 11b. The gas detector 12 installed in the upper access tunnel 2a is connected to the connection pipe 11b via a connection pipe (not shown). A gas discharge pipe 14 is connected to the gas discharge valve 15, and a gas discharge port 14a of the gas discharge pipe 14 is located in the upper access tunnel 2a. Gas detectors 12a are installed in the upper access tunnel 2a and the lower access tunnel 2b, respectively.
[0034]
Since no groundwater exists in the bedrock B, the inside of the drainage body 8, the inside of the connection pipe 11b, and the water collection pipe 16 are hollow. When the high-pressure gas stored in the storage tank 7 leaks, the leaked gas enters the drain body 8 through the drain pipe 8a. The leaked gas that has entered the drainage body 8 flows through the drainage body 8 and reaches the gas discharge valve 15 via the connection pipe 11b. At this time, the gas exhaust valve 15 is closed, and the gas detector 12 analyzes the gas components of the leaked gas. Thereby, the gas concentration in the drainage body 8 can be measured. Gas component analysis is performed on a daily basis, and the presence or absence of leakage can be determined based on changes in gas concentration. Further, since there is no groundwater in the bedrock B, the leaked gas flows through the water collecting pipe 16 and reaches the drain valve 17. At this time, the drain valve 17 is closed.
[0035]
When the leakage of the high-pressure gas stored in the storage tank 7 further proceeds and a large amount of leakage gas is generated, the gas discharge valve 15 and the drain valve 17 are opened to release the leakage gas into the upper access tunnel 2a and the lower access tunnel 2b. When the gas is discharged into the inside, the gas components in the upper access tunnel 2a and the lower access tunnel 2b are measured by the gas detector 12a. As a result, the presence or absence of leakage can be grasped.
[0036]
Although the embodiment of the present invention has been described above, the present invention is not limited to the first, second, and third embodiments, and can be appropriately changed without departing from the gist of the present invention. . For example, in the first, second, and third embodiments described above, the case of the high-pressure gas storage facility constructed in the bedrock is described. However, the present invention relates to the high-pressure gas storage facility constructed in the ground other than the bedrock. The case of facilities is also applicable. In the first and second embodiments, the case where groundwater is present in the ground has been described. However, the present invention can be applied to the case where groundwater does not exist in the ground. Furthermore, in the previous second and third embodiments, the gas amount measuring device 9 and the gas detecting tube 10 were not installed, but the present invention is applied to the case where the gas amount measuring device 9 and the gas detecting tube 10 are installed. But it is applicable.
[0037]
【The invention's effect】
As described above, according to the high-pressure gas storage facility according to the present invention, the presence or absence of leakage of the high-pressure gas stored in the storage tank is constantly measured by regularly measuring the gas component with the installed gas detector. I can judge. When the high-pressure gas stored in the storage tank leaks, the leaked gas enters the drainage body from the drainage pipe and reaches the gas detector via the connection pipe. Since the gas component of the leaked gas is directly measured by the gas detector, the gas can be detected with high accuracy, and the reliability of the leaked gas detection can be improved. In addition, the amount of leaked gas can be grasped by using the gas amount measuring device together.
[0038]
Further, even when the high-pressure gas storage facility according to the present invention is constructed in a rock or ground where no groundwater exists, it is possible to determine whether or not the high-pressure gas stored in the storage tank has leaked. Further, even if some gas enters the drainage body, it is possible to determine whether or not the high-pressure gas stored in the storage tank has leaked while maintaining accuracy.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a high-pressure gas storage facility according to a first embodiment of the present invention.
FIG. 2 is a view showing a drainage body provided in the high-pressure gas storage facility shown in FIG.
FIG. 3 is an elevational view of the outer peripheral surface of the high-pressure gas storage facility shown in FIG.
FIG. 4 is a sectional view illustrating a high-pressure gas storage facility according to a second embodiment of the present invention.
FIG. 5 is a sectional view illustrating a high-pressure gas storage facility according to a third embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cavity part 2 Access tunnel 2a Upper access tunnel 2b Lower access tunnel 3 Top tunnel 4 Vertical shaft 5 Lining material 6 Backfill material 7 Storage tank 8 Drainage body 8a Drainage pipe 8b First water collection pipe 8c Second water collection pipe 8d Connection socket 9 Gas amount measuring device 10 Gas detection pipe 11 Connection pipe 12 Gas detection pipe 13 Pressure gauge 14 Gas discharge pipe 15 Gas discharge valve 16 Water collecting pipe 17 Drain valve 18 Water collecting pit 19 Drain pipe 20 Drain pump 21 Boring hole A Groundwater Existing bedrock B Bedrock without groundwater

Claims (5)

While covering the inner wall of the cavity formed in the rock or the ground with a lining material, a backfill material is interposed between the inner wall and the lining material, and a high-pressure gas flows through the space inside the lining material. A high-pressure gas storage facility used as a storage tank for storing,
A drain body arranged between the inner wall and the backfill material and formed by a drain pipe having a plurality of holes on an outer peripheral surface, connected to the drain body via a connection pipe, and collected by the drain body A high-pressure gas storage facility, comprising: a gas detector that performs component analysis of a gas to be processed. The high-pressure gas storage facility according to claim 1,
The high-pressure gas storage facility, wherein the gas detector is provided above the cavity, and is provided inside a top tunnel connected to the cavity. The high-pressure gas storage facility according to claim 1,
The high-pressure gas storage facility, wherein the gas detector is provided above a borehole provided from the cavity to the surface of the ground. The high-pressure gas storage facility according to claim 1,
The high-pressure gas storage facility, wherein the gas detector is provided inside an access tunnel connected to the cavity and extending obliquely upward to reach the surface of the earth. In the high-pressure gas storage facility according to any one of claims 1 to 4,
A high-pressure gas storage facility comprising a gas amount measuring device for measuring an amount of gas collected by the drainage body, in addition to the gas detector.

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