KR20210059375A - Detection apparatus for leak gas from reservoir tank - Google Patents

Abstract

The present invention relates to a gas leak detection device for a storage tank and a method for detecting a gas leak using the same. The gas leak detection device for a storage tank comprises: a laser light source for irradiating a laser; a reflector disposed on the outer periphery of the storage tank to reflect the laser irradiated from the laser light source so that the trajectory of the reflected laser passes through the storage tank; a photodetector disposed at the distal end of the laser trajectory reflected by the reflector and condensing the laser; and a processor for performing analysis using the laser detected by the photodetector.

Description

Detection apparatus for leak gas from reservoir tank

The present invention relates to a storage tank leak gas detection apparatus, and specifically, to an apparatus and method for detecting gas leaking from a large-scale tank storing gas or liquid using a laser.

Multi-family housing facilities such as apartments have separate storage facilities for storing LPG. It is a 1.6 ton or 2.9 ton, and it is periodically filled using a 10-ton bulky that is transported by truck.

In such a small-sized gas storage tank, an accident occurs in which gas is leaked mainly due to overcharging. By installing one or more gas detection devices capable of detecting one spot around the storage tank, leaking gas can be detected early.

Storage tanks with a diameter of 10 meters or more or storage tanks with a height of 10 meters or more installed in industrial complexes such as Ulsan and Yeocheon have limitations in detecting leaked gas early as a detection method used in small-scale gas storage tanks. Although a plurality of gas detection devices are installed adjacent to the storage tank to detect leaking gas, explosion accidents caused by gas leakage in the storage tank continue to occur both domestically and globally.

Large-scale storage tanks have a wide area through which gas can leak, and when exposed from the top of the tank, there is a problem that the detection device cannot detect at all due to the influence of wind.

In order to solve this problem, it is not only uneconomical to arrange a large number of detection devices in front of a large-scale storage tank, but it is also very difficult to continuously inspect and manage a large number of detection devices.

Patent Document 1 relates to a secondary barrier inspection apparatus and method for a liquefied natural gas storage tank, comprising: a laser generator for generating a laser beam; A beam expander for expanding the laser beam; A slit structure through which the laser beam passing through the beam expander passes to have a predetermined wavelength; And a detector for detecting an ultrasonic signal, wherein the laser beam generated from the laser generator passes through the beam expander and the slit structure and hits the main secondary barrier coupled on the lower insulating board of the liquefied natural gas storage tank, thereby generating ultrasonic waves. , And the generated ultrasonic wave leaks out of the secondary secondary barrier while passing through the adhesive layer for adhering the secondary secondary barrier on the primary secondary barrier and is detected by the detector.

Patent Literature 1 is to detect leakage of storage tanks that store ultra-low temperature liquefied natural gas with very low temperatures, and leaks out of secondary barriers such as poor adhesion of secondary barriers of storage tanks composed of primary and secondary barriers. It relates to a method of detecting and inspecting ultrasonic waves. Although detection is performed using a laser, this is to determine whether the barrier of the storage tank itself is abnormal by examining the ultrasonic waves, and is different from a device that directly detects gas leaking to the outside.

Patent Document 2 relates to a gas leak detection system. As an improvement of the conventional technology that specifies only the direction of gas leakage by a sensor arranged in a circle around a light source and a rotating light source, reflective optical systems are arranged at regular intervals at a specific distance, and the light reflected from each reflective optical system is improved. The present invention relates to a system for detecting a gas leak at a specific interval by providing a detection unit capable of detecting and then sequentially irradiating light to the reflective optical system and using a value detected therefrom.

Patent Document 2 aims to detect a specific leak location, and for this purpose, a plurality of reflectors should be arranged according to the location, and a light source should be sequentially irradiated to the corresponding reflector. Patent Document 2 is for specifying a position, and there is a problem in that a light source must be controlled in order to irradiate light in accordance with a plurality of reflectors and their positions. Unlike the present invention, the detailed technical field is different from the present invention in that it is a technique that specifies the location after it is confirmed that it has already leaked.

Patent Document 3 is a gas leak detection device for drones. A gas detector that measures the concentration of gas using an LED light source is mounted on a drone, which is an unmanned aerial vehicle, and leaks from the gas pipe while flying along the gas pipeline. ) It relates to a device capable of accurately detecting (檢出) gas to determine its location, and to monitor gas leaking from a facility with a high structure such as a gas storage tank.

Patent Document 3 is different from the present invention in that a drone is used, it is not always available, and only a desired part can be monitored for a certain period of time.

Patent Document 4 relates to a toxic gas detection and alarm device using an infrared spectroscopy, and a toxic gas detection and alarm method using the same, which detects toxic gas molecules using an infrared spectroscopy, and a laser is used for alignment and distance measurement. do. In addition, Patent Document 4 is a device that intensively monitors only a specific area.

Patent Document 5 relates to a fuel leak detection apparatus and method, and is a method of photographing and analyzing a laser by scanning a specific area in order to detect the leakage of LNG, and then photographing it with a CCD or the like. However, since it is difficult to detect a minute leaking gas with only a CCD or the like, there is a difference in detailed technology from the present invention, which is intended to be detected early.

As described above, a stable device capable of always detecting minute leaking gas around the entire periphery of a large-scale storage tank and a detection method using the same have not yet been presented.

Republic of Korea Patent Publication No.1947172 (2019.02.01.) Japanese Patent Publication No. 6071519 (2017.01.13) Republic of Korea Patent Publication No. 1649574 (2016.08.12.) Republic of Korea Patent Publication No. 1469017 (2014.11.28.) Japanese Unexamined Patent Publication No. 2014-185914 (2014.10.02) Republic of Korea Patent Publication No. 0481433 (2005.03.28.) Republic of Korea Patent Publication No. 2006-0124111 (2006.12.05.) Republic of Korea Patent Publication No. 2004-0064506 (2004.07.19.)

The present invention is to solve the above problems, and an object of the present invention is to provide a stable device capable of always detecting minute leaking gas in the vicinity of a storage tank and a detection method using the same.

In order to solve the above problems, the present invention comprises: a laser light source unit for irradiating a laser; A reflector disposed around the outer periphery of the storage tank to reflect the laser irradiated from the laser light source so that the trajectory of the reflected laser passes close to the outer surface of the storage tank; A light detection unit disposed at an end of the laser trajectory reflected by the reflection unit and condensing the laser; It provides a gas leak detection apparatus for a storage tank comprising; a processor unit that performs analysis using the laser detected by the photodetector.

The gas leak detection device according to the present invention is a gas leak detection device using TDLAS.

The reflector may include a plurality of reflectors disposed around the outer periphery of the storage tank so that the trajectory of the reflected laser traverses the outer periphery of the storage tank at least once.

The reflector may include a plurality of reflectors disposed around the outer periphery of the storage tank so that the trajectory of the reflected laser may pass through all of the upper and side surfaces of the storage tank.

The laser light source unit is disposed above or below the storage tank, and the reflecting unit is disposed on the opposite side of the laser light source unit in the form of a coil, starting from the laser light source unit and gradually lowering or gradually increasing the trajectory of the reflected laser. It may include a plurality of reflectors disposed to reach the photodetector.

The laser light source unit, the reflection unit, and the light detection unit may all be disposed on the same plane, and the reflecting unit may include a plurality of reflectors disposed so that the trajectory of the reflected laser can traverse the outer periphery of the storage tank only once. .

The plane on which the laser light source, reflector, and photodetector are disposed is placed at a height of less than 1 meter from the ground when the gas to be detected is a gas heavier than air, and adults when the gas to be detected is a gas lighter than air. Can be placed at a height above the eye level of

The laser light source unit, the reflection unit, and the light detection unit may be fixed to at least three or more pillars disposed around the storage tank.

The present invention also provides a method of detecting a gas leak in a storage tank by the gas leak detection device.

In the present invention, 1) minute leaking gas can be detected in the vicinity of the storage tank at all times, 2) minute leakage can be detected by cumulative scanning around the storage tank using one light source, and 3) mechanical movement It is a very economical device and method that can detect all large-scale storage tanks with only one pair of light source and sensor unit, and 4) light source and sensor unit can detect all large-scale storage tanks with only one pair.

1 shows a calculation formula according to Beer-Lambert's law in Tunable Diode Laser Absorption Spectroscopy (hereinafter'TDLAS').
2 is a schematic diagram of a gas leak detection apparatus in which a laser trajectory is disposed on a lower surface of a storage tank according to an embodiment of the present invention.
3 is a schematic diagram of a gas leak detection apparatus in which a laser trajectory is disposed on an upper surface of a storage tank according to an embodiment of the present invention.
4 is a schematic diagram of a gas leak detection apparatus in which a laser trajectory is disposed on an entire side of a storage tank according to an embodiment of the present invention.
5 is a schematic diagram of a gas leak detection apparatus in which a laser trajectory is disposed on the entire side and upper surface of a storage tank according to an embodiment of the present invention.

Hereinafter, it will be described with reference to the drawings according to an embodiment of the present invention, but this is for a more easy understanding of the present invention, and the scope of the present invention is not limited thereto.

In the present application, terms such as "comprise", "have" or "have" are intended to designate the presence of features, numbers, steps, components, parts, or combinations thereof described in the specification, but one or more other It is to be understood that it does not preclude the presence or addition of features, numbers, steps, actions, components, parts, or combinations thereof.

In addition, the same reference numerals are used for portions having similar functions and functions throughout the drawings. Throughout the specification, when a part is said to be connected to another part, this includes not only a case in which it is directly connected, but also a case in which it is indirectly connected with another element interposed therebetween. In addition, the inclusion of a certain component does not exclude other components unless specifically stated to the contrary, but means that other components may be further included.

In measuring the concentration of various gases such as CO, CO2, NOx, and SOx, a measurement method using a laser capable of real-time measurement without sampling the gas to be measured is receiving great attention. Many gas species are mainly absorbed in the infrared region, where the infrared region is near-infrared ray (0.8㎛-1.5㎛), mid-infrared ray (1.5㎛-5.6㎛), far-infrared ray (Far-infrared ray). infrared ray, 5.6㎛-1000㎛). In the mid-infrared ray, the vibration and rotational motion modes of molecules that cause the absorption of molecules are concentrated, so it is applied to the DAS (Direct Absorption Spectroscopy) measurement technique that uses the characteristics of molecules that absorb the wavelength of light to measure the concentration or temperature of the gas to be measured It has an excellent effect on how to measure.

Tunable Diode Laser Absorption Spectroscopy (hereinafter referred to as'TDLAS') uses a variable-wavelength laser as a light source.The initial laser intensity (I0) before passing through the measurement area and the laser after absorption has occurred through the measurement area. This is a method of calculating the concentration and temperature by comparing the ratio of the intensity (I). It is based on the Beer-Lambert law.

As can be seen from the equation of FIG. 1, it can be seen that the absorption amount is proportional to the optical path length (L). Assuming that the concentration of each leaked gas is very fine in the environment where the leaked gas is measured, the values of the main variables for improving the measurement are the measurement distance (L) and temperature (T). In the gas leak detection apparatus according to the present invention, the measurement distance L does not change, but the temperature T continues to change depending on the season, day and night. Hereinafter, technical matters for the TDLAS itself are described in Patent Documents 6, 7, and 8, and detailed descriptions thereof will be omitted.

2 is a schematic diagram of a gas leak detection apparatus 100 in which a laser trajectory is disposed on a lower surface of a storage tank according to an embodiment of the present invention.

The laser irradiated from the laser light source 10 is reflected by the reflecting unit 40 provided in the support unit 30 installed around the storage tank to create a laser trajectory that goes around the bottom of the storage tank once, and then detected by the laser detection unit 20. do.

In the case of FIG. 2, the leaked gas is heavier than air, and by creating a laser trajectory at the lower end of the storage tank 50, it is possible to quickly detect the leaking gas that is heavier than air. Although the laser light source 10 is separately shown in FIG. 2, the laser light source 10 may be installed together with the support part 30 in which the laser detection part 20 is installed, or may be installed in a separate support part. At this time, the height of the laser trajectory is preferably 1 meter or less. A height that does not affect the human eye is more desirable. In FIG. 2, although not directly indicated in the drawing, the reflective portion 40 is also disposed on the rear surface of the storage tank 50. As for the laser detection unit 20, all of the laser detection units used in TDLAS can be used. The laser light source 10 may be any laser to which TDLAS may be applied, and the reflector 40 may use a mirror or a prism.

The gas leak detection apparatus according to the present invention is to detect a gas leak from a storage tank quickly and provide it to a user or an administrator rather than specifying the location of the gas leak.

3 is a schematic diagram of a gas leak detection apparatus 200 in which a laser trajectory is disposed on an upper surface of a storage tank 50 according to an embodiment of the present invention. The apparatus 200 according to FIG. 3 moves the trajectory of the laser to the top of the storage tank 50 in the apparatus 100 according to FIG. 2. In this case, it is preferable to apply when the leaked gas is lighter than air.

4 is a schematic diagram of a gas leak detection device 300 in which a laser trajectory is disposed on the entire side of a storage tank 50 according to an embodiment of the present invention, and FIG. 5 is a storage tank 50 according to an embodiment of the present invention. ) It is a schematic diagram of a gas leak detection apparatus 400 in which a laser trajectory is arranged on the entire side and the upper surface. FIG. 5 is a change in the reflection angle of the reflection part 40 disposed at the top of the support part 30 so that the gas leak detection device according to FIG. 4 is improved so that it can be detected from the upper surface of the storage tank 50.

The gas leak detection apparatuses 300 and 400 according to FIG. 4 or 5 have a coil shape while the laser irradiated from the laser light source 10 disposed above or below the storage tank 50 circumscribes the outer circumference of the storage tank 50 As shown, the reflective part 40 is disposed to be gradually directed downward or upward. In FIGS. 4 and 5, the diagram is illustrated from bottom to top, but it can be changed from top to bottom.

100, 200, 300, 400: gas leak detection device
10: laser light source
20: laser detection unit
30: support
40: reflector
50: storage tank

Claims (8)

A laser light source for irradiating a laser;
A reflector disposed around the outer periphery of the storage tank to reflect the laser irradiated from the laser light source so that the trajectory of the reflected laser passes close to the outer surface of the storage tank;
A light detection unit disposed at an end of the laser trajectory reflected by the reflection unit and condensing the laser;
A gas leak detection apparatus comprising a; a processor unit that performs analysis using the laser detected by the photodetector. The method of claim 1,
The reflecting unit includes a plurality of reflectors disposed on the outer periphery of the storage tank so that the trajectory of the reflected laser traverses the outer periphery of the storage tank at least once. The method of claim 1,
The reflection unit gas leak detection apparatus of a storage tank including a plurality of reflectors disposed around the storage tank so that the trajectory of the reflected laser can pass through all of the top and side surfaces of the storage tank. The method of claim 1,
The laser light source unit is disposed above or below the storage tank,
The reflecting unit includes a plurality of reflectors arranged so that the trajectory of the reflected laser starts from the laser light source unit and gradually descends or goes up in a coil shape to reach the light detection unit disposed on the opposite side with respect to the laser light source unit. Tank gas leak detection device. The method of claim 1,
The laser light source unit, the reflection unit, and the light detection unit are all disposed on the same plane,
The reflecting unit includes a plurality of reflecting mirrors disposed so that the trajectory of the reflected laser traverses the outer periphery of the storage tank only once. The method of claim 5,
The plane on which the laser light source, reflector, and photodetector are disposed is placed at a height within 1 meter from the ground when the gas to be detected is a gas heavier than air, and adults when the gas to be detected is a gas lighter than air. A gas leak detection device in a storage tank that is placed at a height above the eye level. The method of claim 1,
The gas leak detection device of the storage tank is fixed to at least three or more pillars arranged around the storage tank for the laser light source unit, the reflection unit, and the light detection unit. A method of detecting a gas leak in a storage tank by the gas leak detecting device according to any one of claims 1 to 7.

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