Calibration system for sulfur hexafluoride gas recovery equipment

Abstract

The present application relates to the calibration system of sulfur hexafluoride gas recovery equipment, including recovery efficiency detection module, concentration detection module and zero gas cleaning device, recovery efficiency detection module includes analog container, first, second storage tank, weighing device, concentration detection module includes detection container, high range sensor, low concentration sensor, can realize the detection of recovery efficiency of recovery equipment, the quality of recovery gas, and can satisfy the demand of configuration specific concentration SF6 / N2 mixed gas.

Description

Technical Field

[0001] This invention relates to a calibration system for sulfur hexafluoride gas recovery equipment. Background Technology

[0002] Sulfur hexafluoride (SF6) gas recovery equipment is a specialized device used to recover SF6 gas from the arc-extinguishing chamber of circuit breakers. Its working principle is primarily based on cryogenic liquefaction and multi-stage purification technology. Through compression, cooling, and separation steps, it achieves efficient recovery, purification, and storage of SF6 gas. It mainly consists of a processing module comprising compression, refrigeration, purification, and vacuum subsystems, and a storage subsystem primarily composed of carbon steel storage tanks. The recovery equipment requires regular calibration to ensure recovery efficiency and the quality of the recovered gas. Specifically, to test recovery efficiency, the recovery speed, vacuuming speed, recovery rate, and charging speed need to be measured. To test and evaluate the quality of the recovered gas, the SF6 gas concentration in the carbon steel storage tank needs to be measured to determine if the refilling conditions are met. Furthermore, to enable repeated testing, it is also necessary to be able to configure SF6 / N2 mixed gas at specific concentrations. Summary of the Invention

[0003] The purpose of this invention is to provide a calibration system for sulfur hexafluoride gas recovery equipment, which can detect the recovery efficiency and quality of the recovered gas, and can meet the requirements for configuring SF6 / N2 mixed gas of a specific concentration.

[0004] The technical solution of this invention is as follows: The calibration system for the sulfur hexafluoride gas recovery equipment includes: The recycling efficiency detection module includes a simulated container with a standard volume for simulating the arc-extinguishing chamber of a circuit breaker, a first storage tank for storing pure sulfur hexafluoride gas, and a second storage tank for storing pure nitrogen gas. A weighing device is installed at the bottom of the simulated container. The outlets of both the first and second storage tanks are connected to the inlet of the simulated container and are each equipped with a first flow control valve. A pressure sensor is installed at the inlet of the simulated container, and a first switching valve is installed at the outlet. One outlet of the first switching valve is used to connect to the inlet of the recycling equipment. A return pipeline is connected to the inlet of the simulated container, and a first shut-off valve is installed on the return pipeline. The inlet of the first shut-off valve is used to connect to the outlet of the carbon steel storage tank of the recycling equipment. The concentration detection module includes a detection container. The outlet of the detection container is connected to a second switching valve. The two outlets of the second switching valve are respectively connected to a high-range sensor based on the thermal conductivity principle and a low-concentration sensor based on the non-dispersive infrared absorption spectroscopy principle, for detecting the gas concentration of sulfur hexafluoride. The outlets of the high-range sensor and the low-concentration sensor are connected to the inlet of the recovery equipment. The inlet of the detection container is connected to the sampling port of the carbon steel storage tank of the recovery equipment and the other outlet of the first switching valve. A second shut-off valve is provided on the pipe connected to the sampling port. The zero-gas cleaning device has a third shut-off valve at its outlet, and the outlet of the third shut-off valve is connected to the inlet of the detection container for zero-gas cleaning of the concentration detection module.

[0005] The beneficial effects of this technical solution are as follows: This technical solution can achieve multiple detection methods: 1. Detect the recovery rate and vacuuming speed of the recovery equipment for sulfur hexafluoride (SF6) gas or SF6 / N2 mixture: The simulation container of the recovery efficiency detection module simulates the arc-extinguishing chamber of a circuit breaker. Sulfur hexafluoride gas with the same concentration as the SF6 / N2 mixture in the arc-extinguishing chamber is filled into the simulation container through the first and second storage tanks until the pressure reaches 0.8 MPa. The first switching valve is then switched to connect with the inlet of the recovery equipment, and the recovery equipment is started to recover the gas in the simulation container. When the pressure sensor detects that the gas pressure in the simulation container reaches 0.1 MPa (atmospheric pressure), the time t1 taken from 0.8 MPa to 0.1 MPa is recorded. The recovery rate can then be calculated by the program. When the pressure sensor detects that the gas pressure in the simulation container changes from 0.1 MPa to 1.33 × 10⁻⁶ MPa... -3 When the pressure is MPa, i.e. the vacuuming process, the time t2 taken can be recorded to calculate the vacuuming speed. 2. Detecting the inflation rate of the recovery equipment: After the previous step, open the first shut-off valve to connect the outlet of the carbon steel storage tank of the recovery equipment with the inlet of the simulated container, so as to inflate the simulated container. When the pressure sensor detects that the air pressure inside the simulated container has increased from 1.33 × 10⁻⁶, the inflation rate will be measured. -3 When the pressure drops from MPa to 0.8 MPa, record the time t3 taken, and the inflation speed can be calculated. 3. Detect the recovery rate of the recycling equipment: During the process of drawing air into the simulated container through the recycling equipment, the weight change of the simulated container can be detected in real time by a weighing device, and the recovery rate can be calculated. 4. Testing the quality of the recovered gas (whether the concentration meets the standard) and zero-gas cleaning and waste gas recovery: After the recovery equipment completes the recovery of gas from the simulation container, the second shut-off valve is opened for a period of time and then closed. Sample gas is introduced into the detection container through the sampling port of the carbon steel storage tank, so that the second switching valve is switched to connect with the high-range sensor to detect the concentration of sulfur hexafluoride gas in the high-concentration sample. This will determine whether the quality of the recovered gas meets the conditions for refilling. If the conditions for refilling are met, it can be refilled into the circuit breaker arc-extinguishing chamber for reuse. Then, the third shut-off valve is opened for a period of time and then closed. The zero-gas cleaning device fills the detection container with cleaning zero gas (without sulfur hexafluoride gas), such as pure nitrogen, so that the waste gas after testing in the detection container and related pipelines is introduced into the inlet of the recovery equipment to achieve zero-gas cleaning and recycling, avoiding the waste and atmospheric pollution caused by the release of sulfur hexafluoride gas. 5. The auxiliary recovery efficiency detection module prepares sulfur hexafluoride gas or SF6 / N2 mixed gas at a set concentration: the first switching valve is switched to connect with the inlet of the detection container to directly detect the gas concentration in the simulated container. When the concentration detection module is detecting, the second switching valve is switched to connect with the low concentration sensor to detect the sulfur hexafluoride gas concentration in the residual gas in the simulated container. Then, the first flow control valve at the outlet of the first and second storage tanks is controlled to fill the simulated container with sulfur hexafluoride gas and nitrogen. When the range of the low concentration sensor is exceeded, the second switching valve is switched to connect with the high range sensor to continue detecting its concentration. The purpose of preparing the target concentration gas is achieved by adjusting the two first flow control valves.

[0006] It is clear from the above process that the calibration system of this solution can detect the recovery efficiency of the recovery equipment and the quality of the recovered gas, and can meet the requirements for configuring SF6 / N2 mixed gas of a specific concentration.

[0007] Based on the above scheme, the following improvements are made: a trace oxygen sensor is connected to the outlet of the detection container, and a fourth shut-off valve is connected to the outlet of the trace oxygen sensor. The outlet of the fourth shut-off valve is used to connect with the inlet of the recovery equipment.

[0008] Based on the above scheme, the following improvements are made: a humidity sensor is connected to the outlet of the detection container, and a fifth shut-off valve is connected to the outlet of the humidity sensor. The outlet of the fifth shut-off valve is used to connect with the inlet of the recycling equipment.

[0009] Based on the above scheme, the following improvements are made: the zero-gas cleaning device and the second storage tank share a nitrogen source. Attached Figure Description

[0010] Figure 1A schematic diagram of the system principle of a specific embodiment of the calibration system for the sulfur hexafluoride gas recovery equipment of the present invention; Figure 2 for Figure 1 A schematic diagram of the concentration detection module in the image; In the diagram: 1-Recovery efficiency detection module, 11-Simulation container, 12-First storage tank, 13-Second storage tank, 14-Weighing device, 15-First flow control valve, 16-Pressure sensor, 17-First switching valve, 18-Return pipeline, 19-First shut-off valve, 2-Sulfur hexafluoride gas recovery equipment, 21-Processing module, 22-Carbon steel storage tank, 221-Sampling port, 3-Concentration detection module, 31-Detection container, 32-Second switching valve, 33-High-range sensor, 34-Low-concentration sensor, 35-Second shut-off valve, 36-Trace oxygen sensor, 37-Fourth shut-off valve, 38-Humidity sensor, 39-Fifth shut-off valve, 4-Zero gas cleaning device, 41-Nitrogen storage tank, 42-Third shut-off valve. Detailed Implementation

[0011] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention; that is, the described embodiments are merely some embodiments of the invention, and not all embodiments. The components of the embodiments of the invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0012] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0013] It should be noted that relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0014] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0015] A specific embodiment of the calibration system for the sulfur hexafluoride gas recovery equipment of the present invention: as follows Figure 1-2 As shown, the calibration system of the sulfur hexafluoride gas recovery equipment 2 includes a recovery efficiency detection module 1, a concentration detection module 3, and a zero gas cleaning device 4.

[0016] The recycling efficiency detection module 1 includes a simulation container 11 with a standard volume for simulating the arc-extinguishing chamber of a circuit breaker, a first storage tank 12 for storing pure sulfur hexafluoride gas, and a second storage tank 13 for storing pure nitrogen gas. A weighing device 14 is provided at the bottom of the simulation container 11 for weighing the simulation container 11. The outlets of the first storage tank 12 and the second storage tank 13 are both connected to the inlet of the simulation container 11 and are respectively provided with a first flow control valve 15. A pressure sensor 16 is provided at the inlet of the simulation container 11 and a first switching valve 17 is provided at the outlet. One outlet of the first switching valve 17 is used to connect to the inlet of the recycling equipment 2. A return pipeline 18 is connected to the inlet of the simulation container 11. A first shut-off valve 19 is provided on the return pipeline 18. The inlet of the first shut-off valve 19 is used to connect to the outlet of the carbon steel storage tank 22 of the recycling equipment 2.

[0017] The concentration detection module 3 includes a detection container 31. The outlet of the detection container 31 is connected to a second switching valve 32. The two outlets of the second switching valve 32 are respectively connected to a high-range sensor 33 based on the thermal conductivity principle and a low-concentration sensor 34 based on the non-dispersive infrared absorption spectroscopy principle, for detecting the gas concentration of sulfur hexafluoride. The outlets of the high-range sensor 33 and the low-concentration sensor 34 are connected to the inlet of the recovery device 2. The inlet of the detection container 31 is connected to the sampling port 221 of the carbon steel storage tank 22 of the recovery device 2 and the other outlet of the first switching valve 17. A second shut-off valve 35 is provided on the pipe connected to the sampling port 221.

[0018] The outlet of the zero-gas cleaning device 4 is equipped with a third shut-off valve 42, and the outlet of the third shut-off valve 42 is connected to the inlet of the detection container 31 for zero-gas cleaning of the concentration detection module 3.

[0019] A trace oxygen sensor 36 is connected to the outlet of the detection container 31. A fourth shut-off valve 37 is connected to the outlet of the trace oxygen sensor 36. The outlet of the fourth shut-off valve 37 is used to connect with the inlet of the recovery device 2.

[0020] A humidity sensor 38 is connected to the outlet of the detection container 31. A fifth shut-off valve 39 is connected to the outlet of the humidity sensor 38. The outlet of the fifth shut-off valve 39 is used to connect with the inlet of the recycling equipment 2.

[0021] The zero-gas cleaning device 4 shares a nitrogen source with the second storage tank 13.

[0022] This application can perform the following types of detection: 1. Detect the recovery rate and vacuuming rate of sulfur hexafluoride gas or SF6 / N2 mixed gas recovered by the recovery equipment 2: The simulation container 11 of the recovery efficiency detection module 1 simulates the arc-extinguishing chamber of a circuit breaker. Sulfur hexafluoride gas with the same concentration as the SF6 / N2 mixed gas in the arc-extinguishing chamber is filled into the simulation container 11 through the first storage tank 12 and the second storage tank 13 until the concentration reaches 0.8 MPa. The first switching valve 17 is switched to connect with the inlet of the recovery equipment 2, and the recovery equipment 2 is started to recover the gas in the simulation container 11. When the pressure sensor 16 detects that the gas pressure in the simulation container 11 reaches 0.1 MPa (atmospheric pressure), the time t1 taken from 0.8 MPa to 0.1 MPa is recorded, and the recovery rate can be calculated by the program. When the pressure sensor 16 detects that the gas pressure in the simulation container 11 changes from 0.1 MPa to 1.33 × 10⁻³ MPa (vacuuming process), the time t2 taken is recorded, and the vacuuming rate can be calculated. 2. Detect the inflation speed of the recycling device 2: After the previous step, open the first shut-off valve 19 to connect the outlet of the carbon steel storage tank 22 of the recycling device 2 with the inlet of the simulation container 11 so as to inflate the simulation container 11. When the pressure sensor 16 detects that the air pressure in the simulation container 11 changes from 1.33×10-3MPa to 0.8MPa, record the time t3 taken, and the inflation speed can be calculated. 3. Detect the recovery rate of the recycling device 2: During the process of drawing air into the simulated container 11 through the recycling device 2, the weight change of the simulated container 11 can be detected in real time by the weighing device 14, and the recovery rate can be calculated. 4. Testing the quality (concentration) of the gas recovered by the recovery device 2, as well as zero gas cleaning and waste gas recovery: After the recovery device 2 completes the recovery of gas from the simulation container 11, the second shut-off valve 35 is opened for a period of time and then closed. Sample gas is introduced into the detection container 31 through the sampling port 221 of the carbon steel storage tank 22, so that the second switching valve 32 is switched to connect with the high-range sensor 33 to detect the concentration of sulfur hexafluoride gas in the high-concentration sample. This will determine whether the quality of the recovered gas meets the conditions for refilling. If the conditions for refilling are met, it can be refilled into the circuit breaker arc-extinguishing chamber for reuse. Then, the third shut-off valve 42 is opened for a period of time and then closed. The zero gas cleaning device 4 fills the detection container 31 with cleaning zero gas (without sulfur hexafluoride gas), such as pure nitrogen, so that the waste gas in the detection container 31 and related pipelines after testing is introduced into the inlet of the recovery device 2, realizing zero gas cleaning and recycling, and avoiding the waste and atmospheric pollution caused by the release of sulfur hexafluoride gas. 5. The auxiliary recovery efficiency detection module 1 prepares sulfur hexafluoride gas or SF6 / N2 mixed gas at a set concentration: the first switching valve 17 is switched to connect with the inlet of the detection container 31 so as to directly detect the gas concentration in the simulation container 11. When the concentration detection module 3 is detecting, the second switching valve 32 is switched to connect with the low concentration sensor 34 to detect the sulfur hexafluoride gas concentration in the residual gas in the simulation container 11. Then, the first flow control valve 15 at the outlet of the first storage tank 12 and the second storage tank 13 is controlled to fill the simulation container 11 with sulfur hexafluoride gas and nitrogen. When the range of the low concentration sensor 34 is exceeded, the second switching valve 32 is switched to connect with the high range sensor 33 to continue to detect its concentration. The purpose of preparing the target concentration gas is achieved by adjusting the two first flow control valves 15.

[0023] The calibration system of this solution can detect the recovery efficiency and quality of the recovered gas of the recovery device 2, and can meet the requirements for configuring SF6 / N2 mixed gas of a specific concentration.

[0024] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention shall also be included within the scope of protection of the present invention.

Claims

1. A calibration system for a sulfur hexafluoride gas recovery device, characterized in that, include: The recycling efficiency detection module includes a simulated container with a standard volume for simulating the arc-extinguishing chamber of a circuit breaker, a first storage tank for storing pure sulfur hexafluoride gas, and a second storage tank for storing pure nitrogen gas. A weighing device is installed at the bottom of the simulated container. The outlets of both the first and second storage tanks are connected to the inlet of the simulated container and are each equipped with a first flow control valve. A pressure sensor is installed at the inlet of the simulated container, and a first switching valve is installed at the outlet. One outlet of the first switching valve is used to connect to the inlet of the recycling equipment. A return pipeline is connected to the inlet of the simulated container, and a first shut-off valve is installed on the return pipeline. The inlet of the first shut-off valve is used to connect to the outlet of the carbon steel storage tank of the recycling equipment. The concentration detection module includes a detection container. The outlet of the detection container is connected to a second switching valve. The two outlets of the second switching valve are respectively connected to a high-range sensor based on the thermal conductivity principle and a low-concentration sensor based on the non-dispersive infrared absorption spectroscopy principle, for detecting the gas concentration of sulfur hexafluoride. The outlets of the high-range sensor and the low-concentration sensor are connected to the inlet of the recovery equipment. The inlet of the detection container is connected to the sampling port of the carbon steel storage tank of the recovery equipment and the other outlet of the first switching valve. A second shut-off valve is provided on the pipe connected to the sampling port. The zero-gas cleaning device has a third shut-off valve at its outlet, and the outlet of the third shut-off valve is connected to the inlet of the detection container for zero-gas cleaning of the concentration detection module.

2. The calibration system for the sulfur hexafluoride gas recovery equipment according to claim 1, characterized in that, A trace oxygen sensor is connected to the outlet of the detection container. The outlet of the trace oxygen sensor is connected to a fourth shut-off valve. The outlet of the fourth shut-off valve is used to connect to the inlet of the recovery equipment.

3. The calibration system for the sulfur hexafluoride gas recovery equipment according to claim 1, characterized in that, A humidity sensor is connected to the outlet of the detection container, and a fifth shut-off valve is connected to the outlet of the humidity sensor. The outlet of the fifth shut-off valve is used to connect with the inlet of the recycling equipment.

4. The calibration system for the sulfur hexafluoride gas recovery equipment according to claim 1, characterized in that, The zero-gas cleaning device shares a nitrogen source with the second storage tank.

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