Patent Application
20250162793
The present disclosure relates to a vent system and a venting method.
In recent years, in order to realize carbon neutral for decarbonization, a method of supplying a hydrogen gas and safety of supply of the hydrogen gas have been examined in order to utilize the hydrogen gas. For example, Non Patent Literature 1 discloses that a hydrogen pipeline for transporting hydrogen is supplied, and a detector detects leaking hydrogen.
Non Patent Literature 1: Tetsuji Morita “Current Approaches by the City Gas Industry to Supply Hydrogen Through the Pipelines”, The Journal of the Institute of Electrical Installation Engineers of Japan 36 (4), 242-245, 2016
However, in the technique of the related art, as illustrated in
An object of the present disclosure in view of such circumstances is to provide a vent system and a venting method for quickly discharging a gas leaking from a gas transport path in an underground space.
In order to solve the foregoing problem, a vent system according to an aspect of the present disclosure is a vent system discharging a gas in an underground space communicating with a ground space via a pull-up pipe. The vent system includes: an inert gas cylinder disposed in the ground space and configured to generate an inert gas; an inert gas supply pipe for supplying the inert gas to the underground space; and a gas concentration measurement sensor configured to measure a concentration of the gas in the underground space.
In order to solve the foregoing problems, a venting method according to another aspect of the present disclosure is a venting method executed by a vent system discharging a gas in an underground space communicating with a ground space via a pull-up pipe. The venting method includes the steps of generating an inert gas in the ground space, supplying the inert gas into the underground space, and measuring a concentration of the gas in the underground space.
According to the vent system and the venting method of the present disclosure, it is possible to quickly discharge a gas leaking from a gas transportation path in an underground space.
An overall configuration according to the present embodiment will be described with reference to
As illustrated in
The vent system 1 includes a gas leakage detector 11, an inert gas cylinder 12, an inert gas supply pipe 13, a discharge pipe 14, and a gas concentration measurement sensor 15.
The gas leakage detector 11 detects gas leakage from a gas transport pipeline 24 in the underground space S1. The gas transport pipeline 24 is a pipeline for transporting a gas from a supply-side gas tank 25 disposed in the ground space S2 to a consumption-side gas tank 26. In the present embodiment, the gas is hydrogen, and the gas transport pipeline 24 is a hydrogen pipeline, but the present invention is not limited thereto.
A part of the gas transport pipeline 24 is disposed in the underground space S1. Specifically, one end of the gas transport pipeline 24 is connected to a supply port of the supply-side gas tank 25, and is provided such that the gas supplied from the supply-side gas tank 25 is received in the gas transport pipeline 24 from the one end. The other end of the gas transport pipeline 24 is connected to a reception port of the consumption-side gas tank 26 and is provided so that the gas supplied from the supply-side gas tank 25 and transported through the gas transport pipeline 24 is caused to flow into the consumption-side gas tank 26 through the reception port. Further, a part of the gas transport pipeline 24 is disposed inside the underground space S1 and the pipeline 27 that causes the underground spaces S1 to communicate with each other.
As a first example, the gas leakage detector 11 may include a gas concentration measurement sensor installed in the underground space S1. The gas concentration measurement sensor measures a gas concentration in the underground space S1. The gas leakage detector 11 may further include a controller that determines whether the gas concentration is equal to or greater than a leakage threshold. In such a configuration, the controller determines that the gas is leaking when it is determined that the gas concentration is equal to or greater than the leakage threshold. The controller determines that the gas is not leaking when it is determined that the gas concentration is less than the leakage threshold. The controller may cause any output interface to output information indicating whether it is determined that gas is leaking. The controller may be configured by dedicated hardware such as an application specific integrated circuit (ASIC) or a field-programmable gate array (FPGA), may be configured by a processor, or may be configured to include both dedicated hardware and a processor.
As a second example, based on an internal pressure of the supply-side gas tank 25 and an internal pressure of the consumption-side gas tank 26, the gas leakage detector 11 may be configured with a controller that determines whether a gas is leaking. In such a configuration, the controller determines whether a difference between the internal pressure of the supply-side gas tank 25 and the internal pressure of the consumption-side gas tank 26 is equal to or larger than a difference threshold. When the controller determines that the difference is equal to or greater than the difference threshold, the controller determines that the gas is leaking. When the controller determines that the difference is less than the difference threshold, the controller determines that the gas is not leaking. The controller may cause any output interface to output information indicating whether it is determined that gas is leaking.
The inert gas cylinder 12 is disposed in the ground space S2 and generates an inert gas. The inert gas is a chemically stable gas that does not easily react with another element or compound. The inert gas can be, for example, helium, neon, argon, krypton, xenon, radon, a nitrogen gas, carbon dioxide, or the like. The inert gas cylinder 12 may be disposed in the ground space S2. The inert gas cylinder 12 may be able to be transported and moved to the ground space S2 above the underground space S1 where gas leakage has been detected.
The inert gas supply pipe 13 is a pipe for supplying an inert gas to the underground space S1. The inert gas supply pipe 13 has an end on one side (the underground space S1 side) arranged in the underground space S1 and an end on the other side (the ground space S2 side) arranged in the ground space S2. The inert gas cylinder 12 is connected to the end of the inert gas supply pipe 13 on the ground space S2 side, so that the inert gas supply pipe 13 can receive the inert gas generated by the inert gas cylinder 12 from the end on the ground space S2 side and pressure-feed the inert gas.
The inert gas supply pipe 13 may be a flexible pipe disposed inside the pull-up pipe 22. The pull-up pipe 22 may be, for example, a pipe which has already been installed on a utility pole which has already been provided near the underground structure 21 such as a manhole. The flexible pipe is formed of a material that can withstand a pressure feeding force (for example, 0.95 MPa) of the gas. The material can be, for example, a stainless steel (Steel Use Stainless (SUS)). The flexible pipe has a diameter that can be inserted into the pull-up pipe 22. A diameter of the pull-up pipe 22 used for a general utility pole is, for example, 75 mm.
The discharge pipe 14 is a pipe for discharging the gas in the underground space S1 to the ground space S2. In the discharge pipe 14, an end on the underground space S1 side is arranged in the underground space S1, and an end on the ground space S2 side is arranged in the ground space S2. The discharge pipe 14 receives the gas flowing out of the underground space S1 as the inert gas is supplied to the underground space S1 from the end on the underground space S1 side. Then, the gas received from the end on the underground space S1 side reaches the end on the ground space S2 side through the discharge pipe 14 to be discharged to the ground space S2.
The discharge pipe 14 may be a flexible pipe disposed in the pull-up pipe 23. The pull-up pipe 23 may be, for example, a pipe which has already been installed on a utility pole which has already been provided near the underground structure 21 such as a manhole. The flexible pipe is formed of a material that can withstand a pressure feeding force of the gas, and the material can be, for example, a stainless steel material. The flexible pipe has a diameter that can be inserted into the pull-up pipe 23. A diameter of the pull-up pipe 23 used for a general utility pole is, for example, 75 mm.
The gas concentration measurement sensor 15 measures a concentration of the gas in the underground space S1. As one example, the gas concentration measurement sensor 15 may measure the concentration of the gas discharged from the underground space S1 to the ground space S2. In another example, the gas concentration measurement sensor 15 may be a gas concentration measurement sensor including the gas leakage detector 11. In such a configuration, the gas concentration measurement sensor 15 may measure a concentration of the gas in the underground space S1.
Here, a process of constructing the vent system 1 according to the present embodiment will be described with reference to
In step S11, the gas is pressure-fed from the supply-side gas tank 25 to the consumption-side gas tank 26.
In step S12, the gas leakage detector 11 detects whether gas is leaking from the gas transport pipeline 24 in the underground space S1. Here, as described above, the gas leakage detector 11 may detect whether the gas is leaking based on the gas concentration or may detect whether the gas is leaking based on the internal pressure of the supply-side gas tank 25 and the internal pressure of the consumption-side gas tank 26.
When the leakage of the gas is detected, the vent system 1 is constructed in step S13. Specifically, the inert gas cylinder 12 is disposed such that the inert gas generated by the inert gas cylinder 12 is received in the end of the inert gas supply pipe 13 on the ground space S2 side. Here, a flexible pipe may be disposed in the pull-up pipe 22. A flexible pipe may be disposed in the pull-up pipe 23.
In step S14, the vent system 1 is operated.
Here, an operation of the vent system 1 that discharges the gas in the underground space S1 communicating with the ground space S2 via the pull-up pipes 22 and 23 in step S14 will be described with reference to
In step S141, the inert gas cylinder 12 generates an inert gas in the ground space S2.
In step S142, the inert gas supply pipe 13 supplies the inert gas generated in step S141 to the underground space S1.
In step S143, the gas concentration measurement sensor 15 measures a concentration of the gas.
When it is determined in step S143 that the measured concentration of the gas is the predetermined value or more, the process returns to step S141 to repeat the operation. When it is determined in step S143 that the concentration of the gas measured is less than the predetermined value, the vent system 1 ends the operation.
When it is determined that the concentration of the gas is less than the predetermined value and the vent system 1 ends the operation, a worker can enter the underground space S1 and start repair of equipment or the like disposed in the underground space S1. The equipment repaired by the worker is, for example, the gas transport pipeline 24.
As described above, according to the present embodiment, the vent system 1 includes the inert gas cylinder 12 that is disposed in the ground space S2 and pressure-feeds the inert gas, the inert gas supply pipe 13 for supplying the inert gas to the underground space S1, and the gas concentration measurement sensor 15 that measures the concentration of the gas in the underground space S1. Accordingly, the vent system 1 can discharge the gas leaking from the gas transport pipeline 24 from the underground space S1. Further, the leaking gas reaches another underground space S1 through the pipeline 27, and thus another underground space S1 can be inhibited from being filled with the gas. That is, even if the gas leaks from the gas transport pipeline 24, the gas is not accumulated in the underground space S1, and it is possible to inhibit an increase in the concentration of the gas. Since the concentration of the gas in the underground space S1 is measured, it is possible to reliably determine whether the worker can safely enter the underground space S1. Further, the worker can enter the underground space S1 at an early stage by ascertaining a timing at which the concentration of the gas reaches a safe level, and can perform work in the underground space S1 without delay.
According to the present embodiment, the gas concentration measurement sensor 15 measures the concentration of the gas discharged from the underground space S1 to the ground space S2 through the discharge pipe 14. Accordingly, the worker can recognize the concentration of the gas in the ground space S2 without entering the underground space S1 that is likely to be filled with the gas. Therefore, the worker can be more reliably in a safe state.
According to the present embodiment, the inert gas supply pipe 13 may be a flexible pipe disposed inside the pull-up pipe 22. As described above, the pull-up pipe 22 may be a pipe which has already been provided on a utility pole provided near the underground structure 21 such as a manhole, and thus damage may occur due to aging or the like. Therefore, when the pull-up pipe 22 in which the flexible tube has not been arranged supplies the inert gas, the inert gas leaks to the outside of the pull-up pipe 22 due to the damage of the pull-up pipe 22. On the other hand, since the inert gas supply pipe 13 is a flexible pipe disposed inside the pull-up pipe 22, it is possible to inhibit leakage of the inert gas during the supply of the inert gas.
As described above, since the pull-up pipe 22 may be a pipe installed on a utility pole which has already been provided near the underground structure 21 such as a manhole, there is a pull-up pipe which is not formed in view of an influence of the increase in the internal pressure associated with the supply of the inert gas in some cases. Therefore, when the pull-up pipe 22 in which the flexible pipe is not disposed supplies the inert gas, the pull-up pipe 22 is affected by the damage by the inert gas or the like in some cases. On the other hand, since the inert gas supply pipe 13 is a flexible pipe disposed inside the pull-up pipe 22, it is possible to inhibit the influence of the supply of the inert gas on the pull-up pipe 22.
Further, the flexible tube is formed of a material that has flexibility. Therefore, even if a route of the pull-up pipe 22 to the underground space S1 is curved or sloped, the flexible pipe can be arranged inside the pull-up pipe 22.
All documents, patent applications, and techniques described in the present specification are herein incorporated by reference to the same extent as if each individual document, patent application, and technique were specifically and individually described to be incorporated by reference.
Although the above-described embodiments have been described as representative examples, it is apparent to those skilled in the art that many modifications and substitutions can be made within the spirit and scope of the present disclosure. Accordingly, it should not be understood that the present invention is limited by the above-described embodiment, and various modifications or changes can be made within the scope of the claims.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2022/004975 | 2/8/2022 | WO |
