Recovery and reutilization method of backup liquid emptying argon

Abstract

The invention discloses a recycling and reusing method for backup liquid emptying argon, and relates to the technical field of argon recycling, an argon recycling assembly, a liquid argon storage tank assembly and a double-membrane gas holder are included, and the method comprises the steps that the pressure of a storage tank is monitored in real time, and when the pressure reaches the upper limit, emptying gas enters an emptying pipeline; the emptying gas is introduced into the heat exchanger through the recovery pipeline, and the raw material gas enters the double-membrane gas holder through the gas inlet pipeline; raw material gas passes through a compressor and then is conveyed to a heat exchanger to exchange heat with emptying gas, so that the emptying gas is reheated, and the raw material gas is pre-cooled and enters a cold box with cooling capacity; mixing the gas subjected to heat exchange with feed gas, performing compression, decarburization and the like, and purifying in a cold box; and the purified argon is reheated to the use temperature through the heat exchanger, and is conveyed to a single crystal workshop together with normal argon. According to the method, argon emission can be reduced, the resource recycling rate and the cooling capacity utilization rate can be increased, then resource loss is reduced, the potential safety hazard probability can be reduced, and the working efficiency can be improved.

Description

Technical Field

[0001] This invention relates to the field of argon recovery technology, specifically a method for recovering and reusing argon gas from vented backup liquid. Background Technology

[0002] In the field of single crystal production, argon is a key protective gas. Its stable supply and efficient utilization directly affect the quality of single crystals and the continuity of production. Although the industry has widely adopted argon recovery devices to achieve recycling, some shortcomings still exist: the initial start-up of a single crystal furnace relies on high-purity argon gas after liquid argon vaporization as the initial protective gas. When the argon recovery device suddenly trips, an emergency gas source is needed to ensure uninterrupted production. Therefore, a backup liquid argon storage system must be equipped. The liquid argon storage tank needs to meet the gas supply requirements under different operating conditions. As a cryogenic liquid, liquid argon will continuously undergo self-evaporation during the tank's static state. Although this process can maintain the tank's cold balance by absorbing heat, it will cause the pressure inside the tank to gradually increase. When the pressure reaches the operating limit, the traditional method is to directly release the pressure through the venting pipeline. This operation will cause a large amount of high-purity argon to be wasted, and may also cause frost on surrounding pipelines, equipment freezing damage, and even frostbite to personnel, posing safety hazards. Moreover, the directly released cold energy is not recovered, which will increase the energy consumption of subsequent cryogenic purification processes and cause resource waste.

[0003] Based on this, a method for recovering and reusing argon gas from the backup liquid venting is provided, which can eliminate the drawbacks of existing technical solutions. Summary of the Invention

[0004] The purpose of this invention is to provide a method for recovering and reusing argon gas from the venting of backup liquid, so as to solve the problem that the existing process in the background art will cause waste of backup liquid argon gas and pose safety risks.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A method for recovering and reusing argon gas from vented backup liquid involves a system for recovering and reusing argon gas from vented backup liquid, including an argon recovery component, a liquid argon storage tank component, and a double-membrane gas holder. The argon recovery component includes a heat exchanger and a compressor, and the liquid argon storage tank component includes a vaporizer and a buffer tank. The recovery and reuse method specifically includes the following steps: Step S1: Monitor the pressure inside the liquid argon storage tank assembly in real time. When the pressure of the liquid argon storage tank in the liquid argon storage tank assembly reaches the corresponding operating limit, open the electric shut-off valve on the storage tank pipeline and the venting pipeline to allow the venting gas inside the liquid argon storage tank to enter the venting pipeline. Step S2: Introduce the venting gas in the venting pipeline into the heat exchanger of the argon recovery component through the recovery pipeline, and at the same time introduce the raw material gas output from the single crystal workshop into the double membrane gas holder through the gas inlet pipeline. Step S3: Start the compressor of the argon recovery component, and transport the raw gas in the double membrane gas holder to the compressor through the gas pipeline. After being compressed by the compressor, it is transported to the heat exchanger through the compression connection pipeline, so that the raw gas and the venting gas can exchange heat, realize the reheating of the venting gas and the precooling of the raw gas, and at the same time allow the raw gas to carry the cold energy into the cold box. Step S4: The vented gas after heat exchange is mixed with the raw material gas output from the single crystal workshop. The mixed gas is compressed by the compressor and then undergoes decarbonization, deoxygenation and dehydration treatment in sequence before entering the cryogenic purification chamber in the cold box for purification. Step S5: The purified argon gas is sent to the heat exchanger for reheating until the temperature reaches the temperature used in single crystal production. Finally, the qualified argon gas is sent to the single crystal workshop along with the normally supplied argon gas through the pipeline.

[0006] Preferably, step S5 further includes: transporting liquid argon from the liquid argon storage tank assembly to the vaporizer via a vaporization connection pipeline; after the liquid argon is vaporized by the vaporizer, it enters the buffer tank; after the pressure and flow rate are stabilized in the buffer tank, gaseous argon is also transported to the delivery pipeline; and finally, qualified argon gas and vaporized gaseous argon are transported together to the single crystal workshop via the delivery pipeline.

[0007] Preferably, the heat exchanger is used to achieve cold energy recovery and gas temperature regulation through heat exchange between hot and cold media. The compressor is used to compress the raw material gas recovered in the single crystal workshop. The outlet of the compressor is connected to the heat exchanger through a compression connection pipe. The outlet of the heat exchanger is connected to a conveying pipe. The conveying pipe is used to convey the processed argon gas and the normally supplied argon gas to the single crystal workshop.

[0008] Preferably, the liquid argon storage tank assembly is used to store a mixture of liquid argon and argon gas as the medium, and to transport the mixture to the single crystal workshop in the form of argon gas supplied under normal conditions. The liquid argon storage tank assembly includes three first storage tanks and one second storage tank, wherein the first storage tanks are 150m³. 3 Liquid argon storage tanks, the first tank has an operating pressure of 0.60~0.70 MPa, and the second tank has a pressure of 3000 m³. 3The first and second storage tanks operate at a pressure of 16-25 kPa. Both tanks are connected to a venting pipeline on one side via a storage pipe. This venting pipeline is used to release gas to prevent overpressure in the liquid argon storage tanks. The first and second storage tanks are connected by a connecting pipe. A vaporization connection pipe is provided on one side of the first tank. The other end of this vaporization connection pipe is connected to a vaporizer. The outlet of the vaporizer is connected to a buffer tank via the vaporization connection pipe. The vaporizer is used to vaporize the medium in the liquid argon storage tank assembly, converting it into usable gaseous argon. The buffer tank is used to collect the vaporized gaseous argon to stabilize gas pressure and flow rate. The outlet of the buffer tank is connected to a delivery pipeline via a buffer connection pipe.

[0009] Preferably, the dual-membrane gas holder is used to collect the raw material gas output from the single crystal workshop and the vent gas from the liquid argon storage tank. One side of the dual-membrane gas holder is provided with an inlet pipe, and the other end of the inlet pipe extends into the interior of the single crystal workshop. The other side of the dual-membrane gas holder is connected to a gas delivery pipe, and the end of the gas delivery pipe is connected to the inlet of the compressor.

[0010] Preferably, both the first and second storage tanks are equipped with pressure gauges to monitor the liquid argon tank pressure in real time, in order to prevent the liquid argon tank pressure from becoming too high.

[0011] Preferably, a recovery pipeline is connected to one side of the venting pipeline, and one end of the recovery pipeline passes through the heat exchanger and is connected to the air inlet pipeline. Electric shut-off valves are installed on the storage tank pipeline, the venting pipeline, and the recovery pipeline.

[0012] Preferably, one side of the vaporization connection pipe is connected to a cold box cooling pipe for transporting argon gas from the liquid argon storage tank to the heat exchanger for heat exchange, and one end of the cold box cooling pipe passes through the heat exchanger and is connected to the transport pipe.

[0013] Preferably, the compression connection pipe is also equipped with a raw material gas recovery and treatment device for decarbonization, deoxygenation and dehydration treatment, so that the gas entering the heat exchanger through the compression connection pipe is the gas after decarbonization, deoxygenation and dehydration treatment.

[0014] Preferably, the argon recovery component employs cryogenic air separation technology. The heat exchanger is located in a cold box. The heat exchanger reheats the vent gas from the liquid argon storage tank connected to the front end of the dual-membrane gas holder. The vent gas from the liquid argon storage tank is a low-temperature gas. After reheating, the vent gas reaches the temperature conditions used in single crystal production. At the same time, the cold energy of the vent gas is recovered. During the reheating process using the heat exchanger, the vent pipeline passes through the heat exchanger, allowing the cold energy of the vent gas from the liquid argon storage tank to exchange heat with the raw material gas in the argon recovery component. The cold energy is then carried into the cold box to supplement the cold energy required for the cryogenic process.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention introduces the previously directly vented flared gas into an argon recovery assembly via a recovery pipeline. After purification, the flared gas is re-transported to the single crystal workshop, thereby reducing the argon loss rate caused by venting. By reducing the amount of argon venting, energy consumption in the production process is reduced. A heat exchanger is used to achieve heat exchange between the flared gas and the raw material gas. The cold energy released by the low-temperature flared gas can pre-cool the raw material gas, thereby reducing the energy consumption of subsequent cryogenic purification processes. Furthermore, after the flared gas is reheated by the heat exchanger, it can prevent the low-temperature gas from directly entering the production system, reducing the probability of equipment safety risks and the risk of frostbite to personnel exposed to low-temperature gases. In addition, the flared gas in this invention is connected to the front end of the dual-membrane gas holder, thereby avoiding cross-contamination between the flared gas and impurity gases. At the same time, the electric shut-off valve achieves high and low pressure isolation, preventing cross-contamination of argon gases of different pressure levels, ensuring the quality of liquid argon in the liquid argon storage tank, and reducing unnecessary resource waste. Attached Figure Description

[0016] Figure 1 This is a schematic diagram illustrating the steps of the recycling method of the present invention.

[0017] Figure 2 This is a schematic diagram of the recycling system of the present invention.

[0018] Figure 3 This is a schematic diagram of the structure of Comparative Example 1 of the present invention.

[0019] Figure reference numerals: Argon recovery assembly 100, heat exchanger 110, compressor 120, compression connection pipeline 130, conveying pipeline 140, liquid argon storage tank assembly 200, first storage tank 210, second storage tank 220, venting pipeline 230, vaporization connection pipeline 240, vaporizer 250, buffer tank 260, buffer connection pipeline 270, recovery pipeline 280, cold box cooling pipeline 290, double membrane gas holder 300, gas inlet pipeline 310, gas transmission pipeline 320. Detailed Implementation

[0020] 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.

[0021] Argon is used as a protective gas to charge the single crystal furnace during the single crystal production process. Argon recovery systems are widely used in the industry to enable the recycling and reuse of argon, reducing emissions and waste. The argon recovery system is equipped with a backup liquid system for storing purchased liquid argon. Liquid argon is a cryogenic liquid. When it is left to stand still in the liquid argon storage tank for a long time, it will self-evaporate and absorb heat to maintain the internal cooling of the liquid argon storage tank. This will cause the pressure inside the liquid argon storage tank to rise. Once the operating limit is reached, the tank needs to be depressurized. However, the vented air will be directly discharged, resulting in resource waste. Therefore, this invention proposes a method for recycling and reusing the vented air from the backup liquid argon storage tank, as shown in Example 1. Example 1 In this embodiment, as Figure 1 and Figure 2 As shown, a method for recovering and reusing argon gas from backup liquid venting involves a system for recovering and reusing argon gas from backup liquid venting, including an argon recovery component 100, a liquid argon storage tank component 200, and a double-membrane gas holder 300. The argon recovery component 100 includes a heat exchanger 110 and a compressor 120, and the liquid argon storage tank component 200 includes a vaporizer 250 and a buffer tank 260. The recovery and reuse method specifically includes the following steps: Step S1: Monitor the pressure inside the liquid argon storage tank assembly 200 in real time. When the pressure of the liquid argon storage tank in the liquid argon storage tank assembly 200 reaches the corresponding operating limit, open the electric shut-off valve on the storage tank pipeline and the venting pipeline 230 to allow the venting gas inside the liquid argon storage tank to enter the venting pipeline 230. Step S2: The venting gas in the venting pipeline 230 is introduced into the heat exchanger 110 of the argon recovery component 100 through the recovery pipeline 280, and the raw material gas output from the single crystal workshop is introduced into the double membrane gas holder 300 through the gas inlet pipeline 310. Step S3: Start the compressor 120 of the argon recovery component 100, and transport the raw material gas in the double membrane gas holder 300 to the compressor 120 through the gas transmission pipeline 320. After being compressed by the compressor 120, it is transported to the heat exchanger 110 through the compression connection pipeline 130, so that the raw material gas and the venting gas can exchange heat, realize the reheating of the venting gas and the precooling of the raw material gas, and at the same time allow the raw material gas to carry the cold energy into the cold box. Step S4: The vented gas after heat exchange is mixed with the raw material gas output from the single crystal workshop. The mixed gas is compressed by compressor 120, and then undergoes decarbonization, deoxygenation and dehydration treatment in sequence before entering the cryogenic purification chamber in the cold box for purification. The raw material gas refers only to the waste argon gas recovered from the single crystal workshop. The function of the cold box is to provide an ultra-low temperature working environment isolated from the external environment for the internal cryogenic purification chamber. The cryogenic purification process is carried out in the cold box. By utilizing the difference in boiling points between argon gas and impurity gases, the efficient purification of argon gas is achieved through distillation. Step S5: The purified argon gas is sent to the heat exchanger 110 for reheating until the temperature reaches the temperature used in single crystal production. Finally, the qualified argon gas and the normally supplied argon gas are sent to the single crystal workshop through the delivery pipeline 140. In this embodiment, step S5 further includes: transporting liquid argon in the liquid argon storage tank assembly 200 to the vaporizer 250 through the vaporization connection pipe 240; after vaporization by the vaporizer 250, the liquid argon enters the buffer tank 260; after stabilizing the pressure and flow rate, the buffer tank 260 also transports gaseous argon to the delivery pipe 140; finally, the qualified argon gas and the vaporized gaseous argon are transported together to the single crystal workshop through the delivery pipe 140; the single crystal workshop is the end point for argon gas consumption; the production system inside the single crystal workshop is used to produce single crystals; the raw material gas generated in this process is transported to the recycling system; the normal argon gas after recycling and purification is returned to the single crystal workshop and used as a protective gas in a cycle, thereby realizing the recycling and reuse of argon gas. In this embodiment, raw material gas refers to the process waste gas containing impurities (such as hydrogen, nitrogen, oxygen, carbon dioxide, moisture, etc.) output from the single crystal workshop, also known as waste argon. Venting gas refers to the low-temperature gaseous argon generated by the self-evaporation of liquid argon when the pressure inside the liquid argon storage tank assembly 200 reaches the upper limit of operation, discharged through the venting pipeline 230. This gas has high purity but extremely low temperature. Qualified argon gas refers to high-purity argon gas that has reached the purity standard required for single crystal production after the raw material gas or venting gas has undergone cryogenic purification in the cold box through the recycling and reuse system of this invention. Argon gas supplied normally refers to argon gas that is stably supplied to the single crystal workshop through the conveying pipeline 140. Among them, such as Figure 2 As shown, heat exchanger 110 is used to achieve cold energy recovery and gas temperature regulation through heat exchange between hot and cold media. Compressor 120 is used to compress the raw material gas recovered in the single crystal workshop. The outlet of compressor 120 is connected to heat exchanger 110 through compression connection pipe 130. The outlet of heat exchanger 110 is connected to conveying pipe 140. Conveying pipe 140 is used to convey the processed argon gas and the normally supplied argon gas to the single crystal workshop. In this embodiment, considering that the vent gas from the liquid argon storage tank is a cryogenic gas, direct discharge would waste cooling energy. Therefore, this invention uses heat exchanger 110 to exchange the cryogenic gas with the raw material gas recovered from the single crystal workshop. The raw material gas absorbs cooling energy and is pre-cooled, which can prepare for subsequent cryogenic purification. After the vent gas releases cooling energy, its temperature rises, which can prevent the cryogenic gas from directly entering the production system and causing safety hazards. Furthermore, the cryogenically purified argon gas is cryogenic and needs to be heated by heat exchanger 110 with a room temperature medium to reheat the cryogenic argon gas to room temperature, ensuring that the temperature of the argon gas delivered to the single crystal workshop meets the usage conditions. Compressor 120 can adjust the gas pressure to the pressure required by the process, ensuring the normal operation of the gas delivery and purification process. Among them, such as Figure 2As shown, the liquid argon storage tank assembly 200 is used to store a mixture of liquid argon and argon gas, and to transport the mixture to the single crystal workshop in the form of argon gas under normal supply conditions. The liquid argon storage tank assembly 200 includes three first storage tanks 210 and one second storage tank 220. The first storage tanks 210 are 150m³. 3 Liquid argon storage tanks: the first tank 210 operates at a pressure of 0.60~0.70 MPa, and the second tank 220 operates at a pressure of 3000 m³. 3 The liquid argon storage tank, the second tank 220, operates at a pressure of 16~25 kPa. Both the first tank 210 and the second tank 220 are equipped with pressure gauges to monitor the liquid argon storage tank pressure in real time, preventing excessive pressure. The pressure gauges are electrically connected to the control device and the electric shut-off valve. The pressure gauges transmit real-time pressure signals to the control device, which presets an upper pressure limit for each liquid argon storage tank. When the detected operating pressure of a liquid argon storage tank reaches the preset upper limit, the control device automatically drives the electric shut-off valve on the corresponding pipeline to open, allowing the vented gas from the liquid argon storage tank to enter the venting or recovery process. One side of both the first tank 210 and the second tank 220 is connected to the venting pipeline 230 via a tank pipeline. The venting line 230 is used to release gas to avoid overpressure in the liquid argon storage tank. The first storage tank 210 and the second storage tank 220 are connected by a connecting pipe. A vaporization connection pipe 240 is provided on one side of the first storage tank 210. The other end of the vaporization connection pipe 240 is connected to the vaporizer 250. The outlet of the vaporizer 250 is connected to the buffer tank 260 through the vaporization connection pipe. The vaporizer 250 is used to vaporize the medium in the liquid argon storage tank assembly 200 to convert it into usable gaseous argon. The buffer tank 260 is used to collect the vaporized gaseous argon to stabilize the gas pressure and flow rate. The outlet of the buffer tank 260 is connected to the conveying pipe 140 through the buffer connection pipe 270. In this embodiment, the liquid argon storage tank stores a mixture of liquid argon and argon gas. The cooling required for storing the liquid argon is maintained by the heat absorption and vaporization of the liquid argon within the tank through self-evaporation. This causes the internal pressure of the liquid argon storage tank to continuously rise. Once the upper limit of the operating pressure is reached, it needs to be vented to ensure that the liquid argon storage tank does not overpressure. (150m) 3 The venting pressure of the liquid argon storage tank is ≥0.70 MPa, 3000 m³. 3 The venting pressure of the liquid argon storage tank is ≥25Kpa. Therefore, the venting pipelines 230 of each liquid argon storage tank are isolated by electric shut-off valves, which facilitates operation and avoids cross-contamination between high and low pressure. Control valves are installed on other pipelines to facilitate control of the opening and closing status. The recycling system is also equipped with a control device. All electrical components are electrically connected to the control device to facilitate the output of commands. Several electric shut-off valves are also controlled by the control device to increase the overall level of automation. In this embodiment, when the argon recovery component 100 trips or the raw material gas is insufficient, liquid argon is directly supplied to the single crystal workshop after passing through the vaporizer 250 and the buffer tank 260 to ensure continuous production. Liquid argon is a cryogenic liquid and cannot be directly used as a protective gas in the single crystal workshop. The vaporizer 250 can be heated by using ambient heat or process waste heat to convert liquid argon into gaseous argon, which meets the production requirements for the medium form. After the liquid argon is vaporized by the vaporizer 250, the pressure of the gaseous argon may be unstable due to fluctuations in the vaporization rate. The buffer tank 260 can temporarily store the gaseous argon to ensure that the gas pressure delivered to the single crystal workshop meets the requirements of the finished product gas and avoid pressure fluctuations affecting the operation of the single crystal workshop. Among them, such as Figure 2 As shown, the dual-membrane gas holder 300 is used to collect the raw material gas output from the single crystal workshop and the vent gas from the liquid argon storage tank. One side of the dual-membrane gas holder 300 is provided with an inlet pipe 310, and the other end of the inlet pipe 310 extends into the interior of the single crystal workshop. The other side of the dual-membrane gas holder 300 is connected to a gas delivery pipe 320, and the end of the gas delivery pipe 320 is connected to the inlet end of the compressor 120. In this embodiment, the finished gas supply pressure is 0.55~0.60 MPa, and the raw material gas pressure after passing through the double-membrane gas holder 300 is 0.54~0.65 kPa. Since the vent gas from the liquid argon storage tank is qualified argon gas with an oxygen content ≤1.5 ppm, the recovery access point of the vent gas from the liquid argon storage tank is set at the front end of the double-membrane gas holder 300. The double-membrane gas holder 300 is a raw material gas collection device for argon gas recovery, which plays the role of collecting and storing raw material gas. At the same time, it can stabilize the inlet flow pressure of the compressor 120 and avoid the compressor 120 from surging due to changes in gas volume. The liquid argon storage tank stores qualified liquid argon, which is also qualified gas upon self-evaporation. However, the raw material argon gas collected at the inlet of the double-membrane gas holder 300 is unqualified gas, and its pressure is lower than the vent pressure of the liquid argon storage tank. Therefore, this application selects the double-membrane gas holder 300 to avoid contaminating the internal products and prevent unqualified argon gas from contaminating qualified argon gas by cross-contamination between high and low pressure. In this embodiment, the internal temperature of the liquid argon storage tank is ≤-185.9℃, and the vent gas from the liquid argon storage tank is a low-temperature gas. The argon gas used in the single crystal workshop is at room temperature. Therefore, the vent gas recovered from the liquid argon storage tank cannot be directly introduced into the production system in the single crystal workshop. Therefore, the present invention selects the front end of the double-membrane gas holder 300 as the access point for the recovery of vent argon gas from the liquid argon storage tank. The heat exchanger 110 in the argon recovery component 100 is used to reheat the recovered vent gas from the liquid argon storage tank, so as to recover and utilize the cold energy while meeting the usage conditions. Among them, such as Figure 2 As shown, a recovery pipeline 280 is connected to one side of the venting pipeline 230. One end of the recovery pipeline 280 passes through the heat exchanger 110 and is connected to the air inlet pipeline 310. Electric shut-off valves are installed on the storage tank pipeline, the venting pipeline 230 and the recovery pipeline 280. In this embodiment, considering that argon is heavier than air and the vent gas from the liquid argon storage tank is a low-temperature gas, there is a risk of suffocation and frostbite for operators. Therefore, the present invention is equipped with an electric shut-off valve on the corresponding pipeline. The electric shut-off valve can further prevent the cross-flow between high and low pressure and avoid affecting the quality of liquid argon in the liquid argon storage tank. The control device includes a display panel that can monitor the pressure in real time and reduce the probability of safety hazards caused by tank structure rupture or physical disintegration. Among them, such as Figure 2 As shown, one side of the vaporization connection pipe 240 is connected to a cold box cooling pipe 290 for transporting argon gas from the liquid argon storage tank to the heat exchanger 110 for heat exchange. One end of the cold box cooling pipe 290 passes through the heat exchanger 110 and is connected to the delivery pipe 140. The purpose of cold box cooling is to maintain the low temperature environment inside the cold box, ensure the normal operation of cryogenic purification, and ensure that the cryogenic purification effect of the cavity does not decrease. Among them, such as Figure 2 As shown, a raw material gas recovery and treatment device for decarbonization, deoxygenation and dehydration is also installed on the compression connection pipe 130, so that the gas entering the heat exchanger 110 through the compression connection pipe 130 is the gas after decarbonization, deoxygenation and dehydration treatment. In this embodiment, the raw material gas recovered in the single crystal workshop needs to undergo a series of treatments: decarbonization, deoxygenation, dehydration, hydrogen separation, nitrogen separation, etc., to purify the compressed argon gas, remove impurities such as carbon dioxide, oxygen, and moisture, and ensure the purity of the argon gas. Since this treatment method is for the raw material gas recovered from the single crystal and is existing technology, it will not be described further in this invention. Among them, such as Figure 2 As shown, the argon recovery component 100 adopts a cryogenic air separation process. The heat exchanger 110 is set in the cold box. The heat exchanger 110 reheats the vent gas from the liquid argon storage tank connected to the front end of the double membrane gas holder 300. The vent gas is a low-temperature gas. After reheating, the vent gas reaches the temperature conditions used in single crystal production. At the same time, the cold energy of the vent gas is recovered. During the reheating process using the heat exchanger 110, the vent pipeline 230 passes through the heat exchanger 110, so that the cold energy of the vent gas from the liquid argon storage tank exchanges heat with the raw material gas in the argon recovery component 100, and brings the cold energy into the cold box to supplement the cold energy required by the cryogenic process. In this embodiment, the vent gas inside the liquid argon storage tank is a cryogenic gas, and the argon recovery component 100 adopts a cryogenic air separation process. Therefore, the vent pipeline 230 passes through the heat exchanger 110 to exchange heat with the raw material gas (waste argon) recovered from the single crystal workshop, allowing the raw material gas to carry the cold energy into the cold box, thereby achieving the effect of recovering and utilizing the cold energy. Finally, the vent gas inside the liquid argon storage tank follows the raw material gas from the single crystal workshop into the argon recovery component 100. After completing the process, it is finally supplied to the single crystal workshop for use. The argon recovery process is a type of cryogenic air separation, which requires liquid argon to provide the cold energy. In this embodiment, the deoxygenated and dehydrated raw material gas needs to undergo two heat exchange operations: cryogenic purification requires extremely low temperatures, and although the deoxygenated and dehydrated raw material gas removes some impurities, its temperature does not reach extremely low temperatures. At this time, after the first heat exchange, the function of heat exchanger 110 is to pre-cool the raw material gas and recover cold energy. The argon gas after heat exchange enters the cavity. The cavity is essentially a cryogenic separation device, which needs to operate at extremely low temperatures. After the pre-cooled raw material gas enters the cavity, it utilizes the difference in boiling points between argon gas and other impurities. In the low-temperature environment, argon gas will condense into a liquid or high-purity gas, while impurity gases will be separated and discharged. Finally, high-purity argon gas that meets production requirements is obtained in the cavity. The temperature of the purified argon gas in the cavity is extremely low. If it is directly transported to the single crystal workshop, it will cause pipeline freezing and equipment damage. Therefore, a second heat exchange is required. At this time, the function of heat exchanger 110 is to heat and rewarm the low-temperature argon gas to raise its temperature to room temperature, which meets the usage requirements of the single crystal workshop.

[0022] Comparative Example 1 Among them, such as Figure 3 As shown, this comparative example uses existing technology. In this example, the single crystal workshop generates contaminated argon gas (argon gas containing impurities) during production. This gas is transported as raw material gas to the argon recovery unit, which purifies the raw material gas through operations such as deoxygenation, dehydration, and cryogenic separation to obtain high-purity finished gas. The high-purity finished gas is then transported back to the single crystal workshop, realizing the recycling of argon gas and reducing external purchase costs. The liquid argon storage tanks used in this comparative example also include three 150m³ tanks. 3 Liquid argon storage tank and a 3000m 3 The liquid argon storage tank can serve as an emergency gas source when the argon recovery unit malfunctions (such as tripping) or there is insufficient raw material gas, ensuring continuous production in the single crystal workshop. When the pressure inside the liquid argon storage tank exceeds the safe threshold of the operating pressure, excess gas is released through the venting pipe to prevent safety accidents caused by overpressure. Unlike Example 1, this comparative example does not use a liquid argon storage tank venting gas recovery and reuse system, nor does it involve the recovery and reuse operation of liquid argon storage tank venting gas or the cold box replenishment operation of argon in the liquid argon storage tank. This invention can reduce argon emissions, increase resource recovery and utilization rate, increase the utilization rate of cooling capacity, and thus reduce unnecessary resource consumption.

[0023] In summary, this invention incorporates backup liquid argon venting gas into the argon recovery component, which can reduce argon emissions, increase resource recovery and cold energy utilization rates, and achieve dual recovery of argon and cold energy, thereby reducing raw material consumption and energy costs. Furthermore, this invention can also reduce the probability of equipment safety risks, reduce the risk of frostbite to personnel exposed to low-temperature gases, and increase work efficiency.

[0024] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for recovering and reusing argon gas from backup fluid venting, characterized in that, This invention relates to a system for recovering and reusing argon gas from a backup liquid vent, comprising an argon recovery assembly (100), a liquid argon storage tank assembly (200), and a double-membrane gas holder (300). The argon recovery assembly (100) includes a heat exchanger (110) and a compressor (120), and the liquid argon storage tank assembly (200) includes a vaporizer (250) and a buffer tank (260). The recovery and reuse method specifically includes the following steps: Step S1: Monitor the pressure inside the liquid argon storage tank assembly (200) in real time. When the pressure of the liquid argon storage tank in the liquid argon storage tank assembly (200) reaches the corresponding operating limit, open the electric shut-off valve on the storage tank pipeline and the venting pipeline (230) to allow the venting gas inside the liquid argon storage tank to enter the venting pipeline (230). Step S2: The venting gas in the venting pipeline (230) is introduced into the heat exchanger (110) of the argon recovery component (100) through the recovery pipeline (280), and the raw material gas output from the single crystal workshop is introduced into the double membrane gas holder (300) through the gas inlet pipeline (310). Step S3: Start the compressor (120) of the argon recovery component (100) to transport the raw material gas in the double membrane gas holder (300) to the compressor (120) through the gas transmission pipeline (320). After being compressed by the compressor (120), it is transported to the heat exchanger (110) through the compression connection pipeline (130) so that the raw material gas and the venting gas can exchange heat, thereby realizing the reheating of the venting gas and the precooling of the raw material gas. At the same time, the raw material gas carries the cold energy into the cold box. Step S4: The vented gas after heat exchange is mixed with the raw material gas output from the single crystal workshop. The mixed gas enters the compressor (120) for compression, and then undergoes decarbonization, deoxygenation and dehydration treatment in sequence before entering the cryogenic purification chamber in the cold box for purification. Step S5: The purified argon gas is sent to the heat exchanger (110) again for reheating, so that the temperature reaches the temperature used in single crystal production. Finally, the qualified argon gas and the normally supplied argon gas are sent to the single crystal workshop through the delivery pipeline (140).

2. The method for recovering and reusing argon gas from the backup liquid venting according to claim 1, characterized in that, Step S5 further includes: transporting liquid argon in the liquid argon storage tank assembly (200) to the vaporizer (250) through the vaporization connection pipe (240), the liquid argon vaporizes in the vaporizer (250) and enters the buffer tank (260), the buffer tank (260) stabilizes the pressure and flow rate and then transports gaseous argon to the delivery pipe (140), and finally the qualified argon gas and the vaporized gaseous argon are transported to the single crystal workshop through the delivery pipe (140).

3. The method for recovering and reusing argon gas from the backup liquid venting according to claim 1, characterized in that, The heat exchanger (110) is used to achieve cold energy recovery and gas temperature regulation through heat exchange between hot and cold media. The compressor (120) is used to compress the raw material gas recovered in the single crystal workshop. The outlet of the compressor (120) is connected to the heat exchanger (110) through a compression connection pipe (130). The outlet of the heat exchanger (110) is connected to a conveying pipe (140). The conveying pipe (140) is used to convey the processed argon gas and the normally supplied argon gas to the single crystal workshop.

4. The method for recovering and reusing argon gas from the backup liquid venting according to claim 1, characterized in that, The liquid argon storage tank assembly (200) is used to store a mixture of liquid argon and argon gas, and to transport the mixture to the single crystal workshop in the form of argon gas under normal supply conditions. The liquid argon storage tank assembly (200) includes three first storage tanks (210) and one second storage tank (220). The first storage tanks (210) are 150m³. 3 Liquid argon storage tanks, the first storage tank (210) has an operating pressure of 0.60~0.70 MPa, and the second storage tank (220) has a pressure of 3000 m³. 3 The liquid argon storage tank, the second storage tank (220) has an operating pressure of 16~25 kPa. Both the first storage tank (210) and the second storage tank (220) are connected to a venting pipeline (230) on one side via storage tank pipes. The venting pipeline (230) is used to release gas to prevent overpressure in the liquid argon storage tank. The first storage tank (210) and the second storage tank (220) are connected by a connecting pipe. A vaporization connection pipe (240) is provided on one side of the first storage tank (210). The other end of the 0) is connected to the vaporizer (250), the outlet of the vaporizer (250) is connected to the buffer tank (260) through the vaporization connection pipe, the vaporizer (250) is used to vaporize the medium in the liquid argon storage tank assembly (200) to convert it into usable gaseous argon, the buffer tank (260) is used to collect the vaporized gaseous argon to stabilize the gas pressure and flow rate, and the outlet of the buffer tank (260) is connected to the conveying pipe (140) through the buffer connection pipe (270).

5. The method for recovering and reusing argon gas from the backup liquid venting according to claim 1, characterized in that, The dual-membrane gas holder (300) is used to collect the raw material gas output from the single crystal workshop and the vent gas from the liquid argon storage tank. One side of the dual-membrane gas holder (300) is provided with an inlet pipe (310), and the other end of the inlet pipe (310) extends into the interior of the single crystal workshop. The other side of the dual-membrane gas holder (300) is connected to a gas transmission pipe (320), and the end of the gas transmission pipe (320) is connected to the inlet end of the compressor (120).

6. The method for recovering and reusing argon gas from the backup liquid venting according to claim 4, characterized in that, The first storage tank (210) and the second storage tank (220) are both equipped with pressure gauges that monitor the pressure of the liquid argon storage tank in real time to prevent the pressure of the liquid argon storage tank from being too high.

7. The method for recovering and reusing argon gas from backup liquid venting according to claim 4, characterized in that, One side of the venting pipeline (230) is connected to a recovery pipeline (280). One end of the recovery pipeline (280) passes through the heat exchanger (110) and is connected to the air inlet pipeline (310). Electric shut-off valves are installed on the storage tank pipeline, the venting pipeline (230) and the recovery pipeline (280).

8. The method for recovering and reusing argon gas from the backup liquid venting according to claim 4, characterized in that, One side of the vaporization connection pipe (240) is connected to a cold box cooling pipe (290) for transporting argon gas from the liquid argon storage tank to the heat exchanger (110) for heat exchange. One end of the cold box cooling pipe (290) passes through the heat exchanger (110) and is connected to the conveying pipe (140).

9. The method for recovering and reusing argon gas from the backup liquid venting according to claim 3, characterized in that, The compression connection pipe (130) is also equipped with a raw material gas recovery and treatment device for decarbonization, deoxygenation and dehydration treatment, so that the gas entering the heat exchanger (110) through the compression connection pipe (130) is the gas after decarbonization, deoxygenation and dehydration treatment.

10. The method for recovering and reusing argon gas from the backup liquid venting according to claim 3, characterized in that, The argon recovery component (100) adopts a cryogenic air separation process. The heat exchanger (110) is installed in a cold box. The heat exchanger (110) reheats the vent gas from the liquid argon storage tank connected to the front end of the double-membrane gas holder (300). The vent gas from the liquid argon storage tank is a low-temperature gas. After reheating, the vent gas reaches the temperature conditions used in single crystal production. At the same time, the cold energy of the vent gas is recovered. During the reheating process using the heat exchanger (110), the vent pipeline (230) passes through the heat exchanger (110) so that the cold energy of the vent gas from the liquid argon storage tank exchanges heat with the raw material gas in the argon recovery component (100). The cold energy is carried into the cold box to supplement the cold energy required by the cryogenic process.

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