A discharge degradation device and method for SF6 waste gas

Abstract

The application discloses a kind of SF6 waste gas discharge degradation device and method, including gas pump, gas flow rate in each gas circuit can be manually regulated;Gas mixing mechanism is arranged at one end of the gas pump, for mixing background gas in mechanism together with SF6;Reaction mechanism, including air inlet sub-pump, and reactor arranged at one side of the air inlet sub-pump;Tail gas degradation mechanism is used for degrading tail gas, to prevent causing secondary pollution;The application solves the problem that gas is not balanced in each reactor in plasma discharge matrix, reactor leakage, reaction device heat dissipation and degradation of normal pressure or negative pressure waste gas is not easy to air inlet, can effectively improve degradation efficiency, improve the safety of equipment, easy to operate, economy.

Description

Technical Field

[0001] This invention relates to the field of SF6 degradation technology, and in particular to a device and method for the discharge degradation of SF6 waste gas. Background Technology

[0002] SF6 is a synthetic fluoride with an extremely stable molecular structure, excellent arc-quenching and insulating properties, and relatively good thermal conductivity. Therefore, since the 1970s, SF6 has been widely used in various electrical equipment, primarily as an insulating and arc-quenching medium, including gas-insulated circuit breakers and gas-insulated current transformers. As the most potent greenhouse gas among non-carbon dioxide greenhouse gases, SF6 has an extremely long atmospheric lifetime, and its atmospheric concentration is increasing year by year. China's SF6 emissions have already risen from 1.0 Gg / yr in 2005 to approximately 2.0 Gg / yr in 2015, and further to 3.2 (2.6-3.8) Gg / yr in 2018, with emissions still showing a year-on-year increasing trend. More than 95% of SF6 emissions are generated by the power industry. Since the end of the last century, with the increasing severity of environmental problems, the international community has gradually begun to pay attention to the control of SF6 emissions. In recent years, with the goal of "carbon peaking and carbon neutrality", the degradation of SF6 has become an inevitable trend.

[0003] Currently, to reduce the damage of SF6 to the atmospheric environment, the main technologies employed include SF6 purification and recovery, the use of environmentally friendly insulating alternatives to SF6, and the degradation and conversion of SF6 waste gas. Among these, degradation technology is particularly reliable and can achieve high degradation rates. Dielectric barrier discharge low-temperature plasma method has demonstrated advantages in SF6 waste gas degradation, including strong discharge controllability, high energy efficiency, high degradation rate, and simple device structure. Therefore, it has great potential for industrial application, and there are already relevant case studies in SF6 waste gas treatment with excellent results.

[0004] Currently, many scholars have conducted experiments on SF6 waste gas treatment. For example, the patent "Sulfur Hexafluoride Degradation Treatment Device Based on Dielectric Barrier Discharge" published on June 7, 2019, and the patent "A Mixed Gas Treatment Equipment Based on Plasma Technology" published on July 30, 2021, mainly focus on the efficient and harmless degradation of SF6 waste. The input gas is pressurized by a high-pressure gas cylinder, and then mixed for degradation. In the patent "A Mixed Gas Treatment Equipment Based on Plasma Technology", the plasma discharge matrix is ​​directly connected to the initial gas through a three-way and a four-way valve, exposing the reactor to the atmospheric environment.

[0005] The primary method for SF6 degradation is dielectric barrier discharge. Zhang Xiaoxing et al. conducted experiments using dielectric barrier discharge to degrade SF6, exploring the effects of various factors on SF6 degradation by changing input voltage, frequency, dielectric type, background gas, and external gas. Furthermore, a plasma discharge matrix was employed, enabling the simultaneous and efficient degradation of large quantities of waste gas. However, due to the large number of root reactors and their close proximity, heat dissipation and uneven gas inlet issues need to be addressed, and reactor leakage has not yet been considered. Summary of the Invention

[0006] In view of the problem that SF6 is difficult to degrade in the existing technology, the present invention is proposed.

[0007] Therefore, the purpose of this invention is to provide a device and method for the discharge degradation of SF6 waste gas.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0009] As a preferred embodiment of the SF6 waste gas discharge degradation device of the present invention, the device comprises: an air pump, the gas flow rate in each air path of which can be manually adjusted; a gas mixing mechanism, which is located at one end of the air pump and is used to mix the background gas transported in the air pump with SF6; a reaction mechanism, which includes an inlet pump located at one end of the gas mixing mechanism and a reactor located on one side of the inlet pump; and a tail gas degradation mechanism, which is used to degrade the tail gas.

[0010] As a preferred embodiment of the SF6 waste gas discharge degradation device of the present invention, one end of the gas mixing mechanism is fixedly connected to two gas pumps, one of which is used to supply background gas and the other is used to supply degradation gas, and the other end of the gas mixing mechanism is connected to an inlet pump.

[0011] As a preferred embodiment of the SF6 waste gas discharge degradation device of the present invention, an inlet pump is added before the reactor, and the reactor is a plasma discharge matrix reactor.

[0012] In a preferred embodiment of the SF6 waste gas discharge degradation device of the present invention, a packaging box is provided at the outer end of the reaction mechanism, and a cooling fan is provided at the rear of the reaction mechanism.

[0013] As a preferred embodiment of the SF6 waste gas discharge degradation device and method of the present invention, the tail gas degradation mechanism includes an air pump and an alkaline gas washing tank located on one side of the air pump.

[0014] The present invention also proposes a method for the discharge degradation of SF6 waste gas, including the above-mentioned discharge degradation device for SF6 waste gas; and a method for mixing SF6 and background gas, ionizing the degradation gas through a plasma power supply and a voltage regulator, and opening the inlet pump of the reactor to allow the mixed gas in the mixing mechanism to enter the reactor for degradation.

[0015] As a preferred embodiment of the SF6 waste gas discharge degradation device and method described in this invention, the background gas provided by the gas pump can be an inert gas; wherein, the SF6 waste gas has a high concentration, and it is necessary to introduce background gas to dilute it and improve its degradation rate.

[0016] As a preferred embodiment of the SF6 waste gas discharge degradation device and method described in this invention, the background gas is air; wherein, N2 accounts for approximately 78.1% and O2 accounts for approximately 20.9% of the air, and these gases can all promote the degradation of SF6.

[0017] As a preferred embodiment of the SF6 waste gas discharge degradation device and method of the present invention, the reaction mechanism can be flexibly configured to expand or reduce the number of plasma discharge matrix reactors according to the amount of SF6 waste gas.

[0018] As a preferred embodiment of the SF6 waste gas discharge degradation device and method described in this invention, each of the inlet pumps has the same rotation speed, and the degradation gas flow rate and capacity in each reactor are the same, so that the gas degradation is more uniform.

[0019] The beneficial effects of this invention are as follows: This invention solves the problems of uneven gas distribution in each reactor in the plasma discharge matrix, reactor leakage, heat dissipation of the reaction device, and difficulty in gas intake when degrading atmospheric or negative pressure waste gas. It can effectively improve the degradation efficiency and enhance the safety, ease of operation, and economy of the equipment. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0021] Figure 1 This is a schematic diagram of the overall structure of the SF6 waste gas discharge degradation device and method of the present invention.

[0022] Figure 2 This is a graph showing the overall degradation rate of SF6 under different input powers as described in this invention. Detailed Implementation

[0023] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0024] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0025] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0026] Secondly, the present invention is described in detail with reference to the schematic diagrams. When detailing the embodiments of the present invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not according to the usual scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of the present invention. In addition, actual fabrication should include three-dimensional spatial dimensions of length, width, and depth.

[0027] Example 1

[0028] Reference Figure 1 A device for the discharge degradation of SF6 waste gas is provided, comprising an air pump 100, which allows manual adjustment of the gas flow rate in each gas path; and a gas mixing mechanism 200, which is located at one end of the air pump 100 and is used to mix the background gas delivered in the air pump with SF6.

[0029] The reaction mechanism 300 includes an intake pump 301 located at one end of the gas mixing mechanism 200 and a reactor 302 located on one side of the intake pump 301; the exhaust gas degradation mechanism 400 is used to degrade the exhaust gas and prevent secondary pollution.

[0030] Specifically, one end of the gas mixing mechanism 200 is fixedly connected to two air pumps 100, one air pump 100 is used to supply background gas, and the other air pump 100 is used to supply degradation gas. The other end of the gas mixing mechanism 200 is connected to the intake pump 301.

[0031] Furthermore, an intake pump 301 is added before the reactor 302. The reactor 302 adopts a plasma discharge matrix reactor 302. An intake pump 301 is set in each intake gas path. The gas flow rate in the channel of the pump 100 can be viewed through the display. The operation of the pump 100 can be controlled by the knob switch. The gas flow rate in each gas path can be manually adjusted and the gas ratio can be set.

[0032] Furthermore, a sealing box 303 is provided at the outer end of the reaction mechanism 300, and a cooling fan 304 is provided at the rear of the reaction mechanism 300. This fan can both cool the reaction mechanism 300 and blow the gas in the reaction mechanism 300 into the gas box. Then, the gas is introduced into the gas washing tank by the gas pump 100 to wash the gas, preventing gas leakage from the reactor 302 from causing personal injury.

[0033] Furthermore, the exhaust gas degradation mechanism 400 includes an air pump 401 and an alkaline gas scrubbing tank located on one side of the air pump 401. After discharge degradation in the reactor 302, the degraded gas is introduced into the alkaline gas scrubbing tank for treatment, and then the degraded gas is discharged through the exhaust port. The gas in the reaction device is drawn into the air box by the cooling fan 304, and the gas is pumped into the alkaline gas scrubbing tank by the air pump 100 in the air box for scrubbing, preventing gas leakage from the reactor 302.

[0034] Operation process: Step 1, Preparation: First, follow the instructions of this invention. Figure 1 The invention's structural diagram illustrates the equipment connection process, connecting the gas path and electrical components within the device. The gas path includes gas distribution, mixing, reaction degradation, and exhaust gas treatment. All components are tightly connected according to the structural diagram. A background gas detection device is first used to check for airtightness, preventing toxic gas leaks during the reaction from harming personnel and ensuring the stable and orderly operation of the entire device. The monitor is checked regularly to determine if the gas pump 100 is functioning correctly. The alkaline solution level in the gas scrubbing tank is checked regularly to prevent insufficient alkaline solution from releasing undegraded toxic gases into the atmosphere, endangering personnel. The alkaline solution is replaced regularly, and solid sediment in the gas scrubbing tank is cleaned. The electrical components include the plasma power supply, transformer, control panel, gas pump 100, and cooling fan 304. The wiring is first checked to ensure correctness, then its safety and reliability are verified to ensure effective connection. Each component is checked regularly for proper operation, as even a single component failure can affect the entire device.

[0035] Step 2, during degradation: First, turn on the power supply to power on the control panel and power on all components. Then, turn on the cooling fan 304. Next, adjust the two air intake pumps 100 using the knob switch according to the experimental requirements. Turn on the plasma power supply and voltage regulator to ionize the degradation gas. Then, turn on the air intake pump 301 of the reactor 302 to allow the mixed gas in the mixing device to enter the reactor 302 for degradation.

[0036] Step 3, Stop Degradation: First, stop the SF6 gas pump 100, close the SF6 gas input valve, continue to introduce background gas, and maintain stable operation of the reaction device. After ten minutes, turn off the plasma power supply, and after ten minutes, turn off the background gas pump 100 and the reactor 302 pump 100. After five minutes, turn off the cooling fan 304, then turn off the control panel power supply and disconnect the power. At this point, the entire process of this invention is complete.

[0037] Example 2

[0038] Reference Figure 1 This embodiment differs from the first embodiment in that it provides a method for the discharge degradation of SF6 waste gas. SF6 and background gas are mixed, and the gas is ionized by a plasma power supply and a voltage regulator. The inlet pump 301 of the reactor 302 is turned on, so that the mixed gas in the mixing device enters the reactor 302 for degradation.

[0039] Specifically, the background gas provided by the air pump 100 can be an inert gas; among them, the SF6 exhaust gas has a high concentration, so it needs to be diluted by the background gas to improve its degradation rate.

[0040] Furthermore, the background gas is air; in which nitrogen accounts for approximately 78.1% and oxygen accounts for approximately 20.9%, both of which can promote the degradation of SF6.

[0041] It can degrade atmospheric pressure waste gas and even negative pressure waste gas. The atmospheric pressure or negative pressure waste gas to be degraded is pumped into reactor 302 through air pump 100. The background gas in the reaction device can be air, which has zero cost. It is only necessary to open the air inlet to improve its economy.

[0042] The rest of the structure is the same as in Example 1.

[0043] Example 3

[0044] Reference Figure 1-2 This embodiment differs from the previous embodiments in that the reaction mechanism 300 can be flexibly configured to expand or reduce the number of plasma discharge matrix reactors 302 according to the amount of SF6 waste gas.

[0045] Specifically, each intake pump 301 operates at the same speed, and the flow rate and capacity of the degradation gas in each reactor 302 are the same, making the gas degradation more uniform. This avoids the phenomenon of reduced degradation efficiency caused by uneven gas intake in each reactor 302.

[0046] The rest of the structure is the same as in Example 2.

[0047] Experimental conditions:

[0048] Gas composition: 2% SF6 / 98% air

[0049] Input flow rate: 2L / min

[0050] Power supply frequency: 9kHz

[0051] The flow rates in each reactor were almost identical to the set values, and the flow rates in each reactor were balanced.

[0052] Single reactor flow rate

[0053]

[0054] It is important to note that the constructions and arrangements of this application shown in several different exemplary embodiments are merely illustrative. Although only a few embodiments are described in detail in this disclosure, those who consult this disclosure will readily understand that many modifications are possible (e.g., changes in the size, dimensions, structure, shape, and proportions of various elements, as well as parameter values ​​(e.g., temperature, pressure, etc.), installation arrangements, use of materials, color, orientation, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in this application). For example, an element shown as integrally formed may be composed of multiple parts or elements, the position of elements may be inverted or otherwise altered, and the nature or number or position of discrete elements may be changed or altered. Therefore, all such modifications are intended to be included within the scope of the invention. The order or sequence of any process or method steps may be changed or rearranged according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure performing the function described herein, and not only structural equivalents but also equivalent structures. Other substitutions, modifications, alterations, and omissions may be made in the design, operation, and arrangement of the exemplary embodiments without departing from the scope of the invention. Therefore, the present invention is not limited to the specific embodiments, but extends to various modifications that still fall within the scope of the appended claims.

[0055] Furthermore, in order to provide a concise description of exemplary embodiments, not all features of actual embodiments (i.e., those features that are not relevant to the best mode of carrying out the invention as currently considered, or those features that are not relevant to implementing the invention) may be omitted.

[0056] It should be understood that numerous specific implementation decisions can be made during the development of any practical implementation, such as in any engineering or design project. Such development efforts may be complex and time-consuming, but for those of ordinary skill in the art who benefit from this disclosure, the development effort will be a routine task in design, manufacturing, and production without requiring extensive experimentation.

[0057] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A discharge degradation device for SF6 waste gas, characterized in that: include, Air pump (100) allows manual adjustment of gas flow rate in each air path; A gas mixing mechanism (200), located at one end of the gas pump (100), is used to mix the background gas delivered in the gas pump with SF6; The reaction mechanism (300) includes an intake pump (301) located at one end of the gas mixing mechanism (200) and a reactor (302) located on one side of the intake pump (301). Exhaust gas degradation mechanism (400), which is used to degrade exhaust gas; One end of the gas mixing mechanism (200) is fixedly connected to two gas pumps (100), one of which is used to supply background gas and the other is used to supply degradation gas. The other end of the gas mixing mechanism (200) is connected to the intake pump (301). An air inlet pump (301) is added before the reactor (302), and the reactor (302) is a plasma discharge matrix reactor; The reaction mechanism (300) is provided with a packaging box (303) at its outer end, and a cooling fan (304) is provided at the rear of the reaction mechanism (300).

2. The SF6 waste gas discharge degradation device as described in claim 1, characterized in that: The exhaust gas degradation mechanism (400) includes an air pump (401) and an alkaline gas washing tank located on one side of the air pump (401).

3. A method for the discharge degradation of SF6 waste gas, characterized in that, The method comprising the SF6 waste gas discharge degradation device according to any one of claims 1 to 2 includes: The SF6 and background gas are mixed completely; The gas is degraded by ionization using a plasma power supply and voltage regulator; Turn on the inlet pump (301) of the reactor (302) to allow the mixed gas in the mixing mechanism (200) to enter the reactor (302) for degradation.

4. The method for SF6 waste gas discharge degradation as described in claim 3, characterized in that: The background gas is an inert gas; Among them, SF6 exhaust gas has a high concentration, so background gas needs to be introduced to dilute it and improve its degradation rate.

5. The method for SF6 waste gas discharge degradation as described in claim 3, characterized in that: The background gas is air, and the ratio of air to SF6 is 49:

1. Nitrogen accounts for 78.1% and oxygen accounts for 20.9% of the air, and both of these gases can promote the degradation of SF6.

6. The method for SF6 waste gas discharge degradation as described in claim 5, characterized in that: The number of plasma discharge matrix reactors (302) in the reaction mechanism (300) can be flexibly configured according to the amount of SF6 waste gas.

7. The method for SF6 waste gas discharge degradation as described in claim 6, characterized in that: Each of the aforementioned intake pumps (301) operates at the same speed, and the flow rate and volume of the degradation gas in each of the aforementioned reactors (302) are the same, making the gas degradation more uniform. The input flow rate inside the reactor (302) is controlled at 2L / min.

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