Drying system and drying method

Abstract

The application discloses a drying system and a drying method, and belongs to the technical field of acetylene container treatment. The drying system is used for drying an acetylene container and comprises a heating device and a pumping device. The heating device is used for mounting the acetylene container and heating the acetylene container. The pumping device is communicated with the acetylene container and is used for pumping the acetylene container. The drying system further comprises a feeding device. The drying system is configured to: introduce a displacement solvent into the acetylene container through the feeding device, and discharge the displacement solvent after the displacement solvent replaces water molecules in the acetylene container. Therefore, trace water molecules in the micropores of the filler are removed and taken out, and the trace water molecules in the micropores of the filler are effectively removed.

Description

Technical Field

[0001] This application belongs to the field of acetylene container processing technology, specifically relating to a drying system and drying method. Background Technology

[0002] Acetylene containers (such as steel cylinders) are filled with an integral porous calcium silicate packing material. This packing material is prepared by curing, crystallizing, and drying materials such as lime, diatomaceous earth, quartz powder, and reinforcing agents, and has a well-developed microporous capillary system. During use, acetone or DMF is adsorbed into the pores of the packing material as a solvent to dissolve the acetylene. The well-developed porous structure of the calcium silicate packing material can adsorb both the solvent and the acetylene solution, thereby preventing the aggregation of acetylene molecules and the occurrence of explosions.

[0003] In related technologies, drying systems typically employ a combination of high-temperature heating and negative pressure suction for drying. However, calcium silicate filler has an extremely strong affinity for water molecules. Water molecules adsorbed deep within the micropores are subject to both capillary forces and hydrogen bonds, making them difficult to remove once adsorbed. Simply relying on heating and vacuuming is insufficient to remove trace amounts of water molecules from the micropores of the filler. Summary of the Invention

[0004] One of the objectives of this application is to provide a drying system that effectively removes trace amounts of water molecules from the micropores of the packing material, thereby at least partially solving the aforementioned technical problems.

[0005] Another objective of this application is to provide a drying method.

[0006] To achieve the above objectives, according to a first aspect of this application, a drying system is provided for drying acetylene containers, and includes:

[0007] A heating device is used to install and heat the acetylene container.

[0008] An extraction device is connected to the acetylene container to evacuate the acetylene container.

[0009] The drying system also includes a supply device, which is configured to: introduce a displacement solvent into the acetylene container through the supply device; after the displacement solvent replaces the water molecules in the acetylene container, the displacement solvent is discharged.

[0010] In one or more embodiments of this application, the drying system further includes a recovery device and a piping assembly. The recovery device includes a recovery tank and a first condenser. The piping assembly includes a first pipe and a second pipe. The first pipe connects the acetylene container to the recovery tank, and the second pipe connects the acetylene container to the first condenser. The first condenser is connected to the recovery tank.

[0011] In one or more embodiments of this application, the extraction device includes a vacuum pump, and a first condenser connects the vacuum pump to an acetylene container.

[0012] In one or more embodiments of this application, the piping assembly includes a fourth pipe that connects the first condenser to the vacuum pump, and the extraction device further includes a buffer tank disposed on the fourth pipe.

[0013] In one or more embodiments of this application, the drying system further includes a purification device, which includes a distillation column and a second condenser. The piping assembly includes a fifth pipeline and a sixth pipeline. The fifth pipeline connects the recovery tank to the distillation column, and the sixth pipeline connects the second condenser to the supply device. The distillation column is connected to the second condenser.

[0014] In one or more embodiments of this application, the purification apparatus further includes a preheater disposed on a fifth pipeline for heating the displacement solvent flowing from the recovery tank into the distillation column.

[0015] In one or more embodiments of this application, the supply device includes a supply tank and a molecular sieve fixed bed, a sixth pipeline connects the second condenser to the supply tank, and the molecular sieve fixed bed is disposed on the sixth pipeline.

[0016] In one or more embodiments of this application, the piping assembly further includes a ninth piping that connects the supply tank to the molecular sieve fixed bed, so that the supply tank and the molecular sieve fixed bed form a circulation loop.

[0017] In one or more embodiments of this application, the piping assembly further includes a tenth pipeline that connects the supply tank to the acetylene container, and the supply device further includes a third delivery pump and a flow meter, both of which are disposed on the tenth pipeline.

[0018] In one or more embodiments of this application, the heating device includes a heating box and a fixing frame, an acetylene container is located inside the heating box, the acetylene container is connected to the fixing frame, and the fixing frame is configured to drive the acetylene container to flip.

[0019] In one or more embodiments of this application, the drying system further includes a pretreatment device, which includes a gas distribution platform. The pretreatment device has a displacement mode and a vacuum mode. In the displacement mode, the gas distribution platform connects the acetylene container to an inert gas source and a tail gas source, respectively. In the vacuum mode, the gas distribution platform connects the acetylene container to a vacuum source.

[0020] According to a second aspect of this application, a drying method is provided, comprising the following steps:

[0021] A displacement solvent is introduced into the acetylene container through a supply device. After the displacement solvent replaces the water molecules in the acetylene container, the displacement solvent is discharged.

[0022] The extraction device is activated to evacuate the acetylene container, and the heating device is activated to heat the acetylene container.

[0023] In one or more embodiments of this application, the drying method further includes the following steps:

[0024] The first condenser condenses the displacement solvent flowing from the acetylene container to the vacuum pump, and the displacement solvent recovered by the first condenser is passed into a recovery tank for collection.

[0025] In one or more embodiments of this application, the drying method further includes the following steps:

[0026] The displacement solvent discharged from the acetylene container is heated using a preheater, and the heated displacement solvent is then fed into a distillation column.

[0027] The displacement solvent discharged from the distillation column is purified by passing it through a molecular sieve fixed bed and then collected in a supply tank.

[0028] In one or more embodiments of this application, the drying method further includes the following steps:

[0029] Install the acetylene container on the fixed frame. First, switch the pretreatment device to the displacement mode and use the gas distribution platform to connect the acetylene container to the inert gas source and the exhaust gas source respectively. Then, switch the pretreatment device to the vacuum mode and use the gas distribution platform to connect the acetylene container to the vacuum source.

[0030] In one or more embodiments of this application, the displacement solvent is acetone or ethanol, and the water molecule content in the displacement solvent introduced into the acetylene container by the supply device is <3ppm.

[0031] Compared with the prior art, the drying system of this application introduces a displacement solvent into the acetylene container through a supply device. After the displacement solvent replaces the water molecules in the acetylene container, the displacement solvent is discharged, thereby removing and carrying away trace water molecules in the micropores of the packing material, effectively removing trace water molecules in the micropores of the packing material. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the drying system in one embodiment of this application.

[0034] Explanation of reference numerals in the attached figures:

[0035] 1. Acetylene container;

[0036] 21. Heating box; 22. Mounting frame;

[0037] 31. Vacuum pump; 32. Buffer tank; 33. Exhaust gas tank;

[0038] 41. Supply tank; 42. Molecular sieve fixed bed; 43. Second transfer pump; 44. Third transfer pump; 45. Flow meter;

[0039] 51. Recycling tank; 52. First condenser;

[0040] 61. First pipeline; 62. Second pipeline; 63. Third pipeline; 64. Fourth pipeline; 65. Fifth pipeline; 66. Sixth pipeline; 67. Seventh pipeline; 68. Eighth pipeline; 69. Ninth pipeline; 610. Tenth pipeline;

[0041] 71. Distillation column; 72. Second condenser; 73. Preheater; 74. First transfer pump;

[0042] 8. Pretreatment device. Detailed Implementation

[0043] To enable those skilled in the art to better understand the technical solutions in this disclosure, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure.

[0044] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0045] According to the first aspect of this application, referring to Figure 1 This disclosure provides a drying system for drying an acetylene container 1.

[0046] For example, acetylene container 1 is a dissolving acetylene cylinder, which is filled with an integral porous calcium silicate filler. The calcium silicate filler is prepared by curing, crystallizing and drying materials such as lime, diatomaceous earth, quartz powder and reinforcing agents. It has an interconnected microporous capillary system that can adsorb acetone or DMF as a solvent to dissolve acetylene, thereby preventing acetylene molecule aggregation and explosion accidents.

[0047] In some embodiments, the drying system includes a heating device and an extraction device.

[0048] In some embodiments, the heating device is used to install the acetylene container 1 and to heat the acetylene container 1.

[0049] In some embodiments, the extraction device is connected to the acetylene container 1 to evacuate the acetylene container 1.

[0050] In some embodiments, the drying system further includes a supply device, and the drying system is configured to: introduce a displacement solvent into the acetylene container 1 through the supply device, and after the displacement solvent has replaced the water molecules in the acetylene container 1, discharge the displacement solvent.

[0051] In this embodiment, a displacement solvent is introduced into the acetylene container 1 through a supply device. The displacement solvent molecules and the water molecules in the micropores of the packing are diffused, exchanged and dissolved, and carried out by the displacement solvent molecules. The displacement solvent actively enters the micropores to displace the water molecules and carries the water molecules out when the displacement solvent is discharged.

[0052] By using solvent displacement to remove water molecules from deep within the micropores, deep dehydration can be achieved without raising the temperature to 130-150℃, thus avoiding damage to the microporous structure and mechanical strength of the calcium silicate packing at high temperatures, ensuring the service life of the packing and the safety of the acetylene container 1.

[0053] Compared to the method of slowly vaporizing trace amounts of moisture by heating at high temperatures for a long time, this application achieves efficient dehydration by rapidly diffusing and exchanging the solvent with water, which greatly shortens the processing time and improves production efficiency.

[0054] For example, porous calcium silicate filler has a well-developed microporous structure, which has a strong affinity for water molecules. Water molecules adsorbed deep within the micropores are doubly bound by capillary forces and hydrogen bonds, making it difficult for conventional heating, drying, and vacuuming methods to effectively remove moisture from the deep pores. By introducing a displacement solvent into the acetylene container 1 through a supply device, the moisture content inside the acetylene container 1 can be effectively reduced to below 3 ppm, meeting the stringent requirements for electronic-grade acetylene.

[0055] In some embodiments, continue to refer to Figure 1 As shown, the drying system also includes a recovery device and a piping assembly. The recovery device includes a recovery tank 51 and a first condenser 52. The piping assembly includes a first pipe 61 and a second pipe 62. The first pipe 61 connects the acetylene container 1 to the recovery tank 51, and the second pipe 62 connects the acetylene container 1 to the first condenser 52. The first condenser 52 is connected to the recovery tank 51.

[0056] In this embodiment, the recovery tank 51 is connected to the acetylene container 1 via the first pipeline 61, thereby directly recovering the liquid displacement solvent in the acetylene container 1 (for example, the liquid displacement solvent containing water discharged from the acetylene container 1 after the solvent injection and rinsing stage is completed).

[0057] The first condenser 52 is connected to the acetylene container 1 via the second pipeline 62, thereby condensing and recovering the displacement solvent in the acetylene container 1 in a gaseous or gas-liquid mixture state (for example, displacement solvent vapor or gas-liquid mixture extracted from the acetylene container 1 during the negative pressure heating and drying stage). The first condenser 52 is connected to the recovery tank 51. The gaseous displacement solvent is liquefied in the first condenser 52 and then passed into the recovery tank 51 for collection, thereby realizing the recovery and reuse of the displacement solvent.

[0058] For example, the piping assembly also includes a third pipe 63, through which the first condenser 52 is connected to the recovery tank 51. A cooling medium (such as cooling water or refrigerant) can be provided to the first condenser 52 via a cooling medium circulation device to accelerate the cooling effect of the first condenser 52. Preferably, the cooling water temperature is ≤15°C to ensure sufficient liquefaction of the gaseous displacement solvent and improve recovery efficiency.

[0059] In some embodiments, continue to refer to Figure 1 As shown, the extraction device includes a vacuum pump 31, and a first condenser 52 connects the vacuum pump 31 to the acetylene container 1.

[0060] In this embodiment, the first condenser 52 is connected between the vacuum pump 31 and the acetylene container 1, so that when the extraction device uses the vacuum pump 31 to evacuate the acetylene container 1, the gas flow in the acetylene container 1 is first condensed by the first condenser 52 and then flows into the vacuum pump 31. This can effectively recover the displacement solvent contained in the gas flow and also prevent the displacement solvent (such as the gas-liquid mixture displacement solvent) from flowing into the vacuum pump 31 and causing damage to the vacuum pump 31.

[0061] In some embodiments, continue to refer to Figure 1 As shown, the piping assembly includes a fourth pipe 64, which connects the first condenser 52 to the vacuum pump 31. The extraction device also includes a buffer tank 32, which is disposed on the fourth pipe 64.

[0062] In this embodiment, the vacuum pump 31 and the first condenser 52 are connected through the fourth pipeline 64. By setting a buffer tank 32 on the fourth pipeline 64, the displacement solvent in the gas flow passing through the fourth pipeline 64 can be further condensed and recovered, preventing the gaseous displacement solvent from flowing into the vacuum pump 31.

[0063] For example, the extraction device also includes a vacuum level detection instrument for real-time monitoring of the vacuum level inside the acetylene container 1, which can shut down the vacuum pump 31 when the vacuum level meets the requirements. The buffer tank 32 is equipped with a refrigerant jacket and a refrigerant inner coil to further prevent displacement solvent vapor or gas-liquid mixture from directly entering the vacuum pump 31.

[0064] The extraction device also includes an exhaust gas tank 33, which is connected to the downstream outlet of the vacuum pump 31. The exhaust gas tank 33 is filled with adsorption materials such as activated carbon to adsorb residual replacement solvent vapors in the exhaust gas, and is connected to the outdoor area through an exhaust pipe for safe discharge to avoid environmental pollution.

[0065] In some embodiments, continue to refer to Figure 1 As shown, the drying system also includes a purification device, which includes a distillation column 71 and a second condenser 72. The piping assembly includes a fifth pipe 65 and a sixth pipe 66. The fifth pipe 65 connects the recovery tank 51 to the distillation column 71, and the sixth pipe 66 connects the second condenser 72 to the supply device. The distillation column 71 is connected to the second condenser 72.

[0066] In this embodiment, the replacement solvent recovered in the recovery tank 51 can flow into the distillation column 71 through the fifth pipeline 65, thereby performing distillation separation (preferably micro-negative pressure distillation) on the recovered replacement solvent, and obtaining a high-purity gaseous replacement solvent with low water molecule content (e.g., <10ppm) at the top of the column.

[0067] The gaseous displacement solvent is condensed into a liquid state by the second condenser 72, and then flows to the supply device through the sixth pipeline 66. The purified displacement solvent returns to the supply device, thus realizing the recycling of the displacement solvent, which reduces processing costs and environmental emissions.

[0068] For example, the piping assembly also includes a seventh pipe 67 and an eighth pipe 68, wherein the seventh pipe 67 connects the inlet of the second condenser 72 to the distillation column 71, and the eighth pipe 68 connects the outlet of the second condenser 72 to the distillation column 71.

[0069] The gaseous displacement solvent flowing out from the top of the distillation column 71 flows into the second condenser 72 through the seventh pipeline 67 for condensation and liquefaction. After being condensed by the second condenser 72, part of the displacement solvent flows to the supply device through the sixth pipeline 66, and the other part of the displacement solvent flows back to the distillation column 71 through the eighth pipeline 68, so that the distillation column 71 is kept in balance.

[0070] The reflux ratio of the second condenser 72 can be controlled by a reflux ratio controller, preferably between 3:1 and 5:1.

[0071] The residual liquid from the bottom of distillation column 71 is collected in a waste liquid tank for centralized treatment. Distillation column 71 is a sieve tray column with 20-40 trays and an operating pressure of -0.03 to -0.01 MPa (slight negative pressure).

[0072] In some embodiments, continue to refer to Figure 1 As shown, the purification apparatus also includes a preheater 73, which is installed on the fifth pipeline 65 to heat the displacement solvent flowing from the recovery tank 51 into the distillation column 71.

[0073] In this embodiment, the displacement solvent in the recovery tank 51 is heated by the preheater 73 and then sent to the distillation column 71 to facilitate purification in the distillation column 71 and improve purification efficiency.

[0074] For example, the recovered acetone is heated to 85-95°C by preheater 73 and then fed into distillation column 71.

[0075] The purification apparatus also includes a first transfer pump 74, which is installed on the fifth pipeline 65, thereby pumping the displacement solvent in the recovery tank 51 into the preheater 73 and then to the distillation column 71.

[0076] In some embodiments, continue to refer to Figure 1 As shown, the supply device includes a supply tank 41 and a molecular sieve fixed bed 42. The sixth pipeline 66 connects the second condenser 72 to the supply tank 41, and the molecular sieve fixed bed 42 is disposed on the sixth pipeline 66.

[0077] In this embodiment, after the gaseous replacement solvent is condensed into a liquid state by the second condenser 72, it flows to the supply tank 41 through the sixth pipeline 66. It is first purified by the molecular sieve fixed bed 42 before flowing into the supply tank 41 for storage.

[0078] After purification by the molecular sieve fixed bed 42, trace amounts of water in the solvent can be further removed, ensuring that the water molecule content is <3ppm.

[0079] For example, the supply device also includes a second delivery pump 43, which is disposed on the sixth pipeline 66, thereby pumping the displacement solvent condensed by the second condenser 72 into the molecular sieve fixed bed 42 and delivering it to the supply tank 41.

[0080] In some embodiments, continue to refer to Figure 1 As shown, the piping assembly also includes a ninth pipe 69, which connects the supply tank 41 to the molecular sieve fixed bed 42 so that the supply tank 41 and the molecular sieve fixed bed 42 form a circulation loop.

[0081] In this embodiment, the displacement solvent purified by the molecular sieve fixed bed 42 flows into the supply tank 41 for storage through the sixth pipeline 66. The displacement solvent in the supply tank 41 can also return to the molecular sieve fixed bed 42 for purification through the ninth pipeline 69, thereby forming a circulation loop between the supply tank 41 and the molecular sieve fixed bed 42, ensuring that the water molecule content in the supply tank 41 is continuously <3ppm, thereby ensuring the drying effect of the acetylene container 1.

[0082] For example, after closing the connection between the second condenser 72 and the molecular sieve fixed bed 42, the second transfer pump 43 can be used as a power source to circulate the fluid between the supply tank 41 and the molecular sieve fixed bed 42. Since the water removal capacity of the distillation column 71 is limited, typically only able to treat up to 10 ppm, deep water removal relies on circulation to the molecular sieve fixed bed 42. The water molecule content in the replacement solvent in the supply tank 41 is <3 ppm, ensuring that secondary pollution will not occur due to water carried by the solvent itself.

[0083] In some embodiments, continue to refer to Figure 1 As shown, the piping assembly also includes a tenth pipe 610, which connects the supply tank 41 to the acetylene container 1. The supply device also includes a third delivery pump 44 and a flow meter 45, both of which are mounted on the tenth pipe 610.

[0084] In this embodiment, the supply tank 41 is used to store the replacement solvent (e.g., water molecule content < 3ppm), and the replacement solvent in the supply tank 41 is introduced into the acetylene container 1 through the tenth pipeline 610.

[0085] Powered by a third transfer pump 44, the displacement solvent in the supply tank 41 is pumped into the acetylene container 1. A flow meter 45 detects the amount of displacement solvent entering the acetylene container 1, enabling precise control of the injected solvent volume and flow rate, thus achieving accurate control of the pumped amount.

[0086] For example, the drying system can dry at least one acetylene container 1. When multiple acetylene containers 1 are dried, the multiple acetylene containers 1 can be connected to the tenth pipeline 610 respectively to achieve simultaneous or alternating drying of multiple acetylene containers 1, which is suitable for industrial batch processing.

[0087] In some embodiments, continue to refer to Figure 1 As shown, the heating device includes a heating box 21 and a fixing frame 22. The acetylene container 1 is located inside the heating box 21 and is connected to the fixing frame 22. The fixing frame 22 is configured to drive the acetylene container 1 to rotate.

[0088] In this embodiment, the acetylene container 1 is located inside the heating box 21, which can be used to uniformly heat the acetylene container 1. The heating method can be electric heating, steam heating or heat transfer oil heating.

[0089] The mounting bracket 22 can rotate the acetylene container 1 (e.g., with the bottle opening facing down), thereby utilizing the gravity of the displacement solvent to discharge the liquid in the acetylene container 1 into the recovery device without the need for additional power, thus reducing the cost of use.

[0090] During the solvent injection stage, the acetylene container 1 is positioned with its opening facing upwards to facilitate the full injection and immersion of the porous packing material by the replacement solvent. After the replacement is completed, the fixing frame 22 drives the acetylene container 1 to rotate so that the opening faces downwards, allowing the replacement solvent containing moisture to be discharged under gravity.

[0091] During the negative pressure heating and drying stage, the acetylene container 1 is heated by the heating box 21 and a vacuum is drawn by the vacuum pump 31, which can vaporize and remove the displacement solvent remaining in the pores of the packing.

[0092] First, a liquid displacement solvent is used to "actively" enter the micropores to carry out the water, and then the solvent is removed by vaporization, thus overcoming the technical bottleneck that it is difficult to effectively remove water from deep within the micropores by simply relying on vaporization.

[0093] For example, when the heating box 21 heats the acetylene container 1, the temperature is controlled between 40-80°C (preferably 50-70°C) to ensure effective vaporization of the solvent and avoid damage to the packing structure and the performance of the acetylene container 1 due to excessively high temperature.

[0094] The processing temperature in this application is controlled at 50-70℃, which is far lower than the high temperature of 130-150℃ required for simple heating and vaporization. This effectively avoids damage to the microporous structure and mechanical strength of the calcium silicate filler caused by high temperature, and ensures the service life of the filler.

[0095] The heating device may also include a temperature control component, which includes a temperature sensor and a thermostat for precisely controlling the heating temperature.

[0096] In some embodiments, continue to refer to Figure 1 As shown, the drying system also includes a pretreatment device 8, which includes a gas distribution platform. The pretreatment device 8 has a displacement mode and a vacuum mode. In the displacement mode, the gas distribution platform connects the acetylene container 1 to the inert gas source and the exhaust gas source respectively. In the vacuum mode, the gas distribution platform connects the acetylene container 1 to the vacuum source.

[0097] In this embodiment, the gas distribution platform integrates an inert gas pipe, a tail gas pipe, and a vacuum pipe. These pipes are connected to the acetylene container 1, thereby connecting the acetylene container 1 to the inert gas source, the tail gas source, and the vacuum source. The pretreatment device 8 also includes a control panel, which allows for easy switching between different modes.

[0098] For example, after the acetylene container 1 is installed on the mounting bracket 22 and connected to the tenth pipeline 610, the acetylene container 1 is pretreated.

[0099] Using the pretreatment device 8, in the replacement mode, an inert gas (e.g., nitrogen) is introduced into the acetylene container 1. The exhaust gas in the acetylene container 1 is then directed to the exhaust gas source, thereby purging and replacing the interior of the acetylene container 1 with inert gas, ensuring that there is no acetylene residue inside the acetylene container 1 and guaranteeing operational safety. Multiple replacements can be performed to ensure no acetylene residue remains.

[0100] Using the pretreatment device 8, the acetylene container 1 is evacuated in vacuum mode, which facilitates the introduction of the replacement solvent into the acetylene container 1 by the supply tank 41.

[0101] During solvent injection, the acetylene container 1 is in a vacuum state, so the replacement solvent can fill the acetylene container 1. Furthermore, due to the vacuum state, unidirectional injection can be achieved without exhaust gas.

[0102] After pretreatment, a displacement solvent is introduced into acetylene container 1 for displacement. Additionally, after displacement, when draining the displacement solvent from acetylene container 1, inert gas can be introduced into acetylene container 1 through a gas distribution platform to accelerate the flow of the displacement solvent to the recovery device, improving drainage efficiency and preventing residual displacement solvent in acetylene container 1. If complete drainage is not possible, inert gas can be introduced into the pretreatment device 8 to assist drainage.

[0103] According to a second aspect of this disclosure, a drying method for the drying system as described above is provided, comprising the following steps:

[0104] S20. A replacement solvent is introduced into the acetylene container 1 through a supply device. After the replacement solvent replaces the water molecules in the acetylene container 1, the replacement solvent is discharged.

[0105] S30. Start the extraction device to evacuate the acetylene container 1, and start the heating device to heat the acetylene container 1.

[0106] In this embodiment, the porous calcium silicate packing material in the acetylene container 1 is first rinsed with a displacement solvent of low water content (e.g., content <3ppm). Through the diffusion, exchange and dissolution of water molecules in the micropores of the packing material, the water molecules adsorbed deep in the micropores of the packing material are displaced and carried out with the solvent. Then, the solvent remaining in the pores of the packing material is vaporized and removed by negative pressure heating.

[0107] First, a liquid displacement solvent is used to "actively" enter the micropores to carry out the water, and then the solvent is removed by vaporization, thus overcoming the technical bottleneck that it is difficult to effectively remove water from deep within the micropores by simply relying on vaporization.

[0108] For example, acetone or ethanol with a water content of <3 ppm is metered into the acetylene container 1 from the supply tank 41 via a third delivery pump 44. The injection amount should be sufficient to submerge the porous packing material inside the acetylene container 1 (e.g., the injection amount is 60%-90% of the internal volume of the acetylene container 1).

[0109] After injection, maintain the solution for 2-4 hours to allow the replacement solvent to fully penetrate into the microporous structure of the calcium silicate filler. During this process, the replacement solvent molecules diffuse and exchange with the water molecules adsorbed on the inner wall of the micropores. The water molecules are replaced by the solvent molecules and desorbed from the filler surface, entering the liquid-phase replacement solvent.

[0110] The acetylene container 1 is then inverted using the fixing frame 22, allowing the displacement solvent containing moisture to drain from the acetylene container 1 under its own gravity. If complete drainage is not possible, an inert gas can be introduced through the pretreatment device 8 to assist in the drainage process.

[0111] Repeat the process of injecting fresh replacement solvent and draining the aqueous replacement solvent 3-5 times until the water content of the drained solvent reaches the preset requirement (e.g., water molecule content < 3 ppm). Use a multiple injection-soaking-draining cyclic rinsing method to ensure that the moisture deep in the micropores of the packing is fully replaced and carried out.

[0112] For example, after closing the tenth pipeline 610, the vacuum pump 31 is started to evacuate the inside of the acetylene container 1, and the pressure inside the acetylene container 1 is reduced to below -0.095 MPa.

[0113] Simultaneously, heating chamber 21 is activated to heat acetylene container 1 to 50-70℃ (preferably 60±5℃). Under this temperature and negative pressure conditions, the displacement solvent remaining in the micropores of the packing rapidly vaporizes.

[0114] The vaporized displacement solvent vapor (or gas-liquid mixture) is extracted from the acetylene container 1 under negative pressure and enters the first condenser 52.

[0115] During this negative pressure heating and drying stage, the temperature is controlled between 40-80℃ (preferably 50-70℃) to ensure effective solvent vaporization while avoiding damage to the packing structure and the performance of the acetylene container 1 (e.g., a steel cylinder) due to excessively high temperatures. The processing conditions are mild and do not damage the packing.

[0116] The processing temperature in this application is controlled at 50-70℃, which is far lower than the high temperature of 130-150℃ required for simple heating and vaporization, effectively avoiding damage to the microporous structure and mechanical strength of calcium silicate filler caused by high temperature.

[0117] In some embodiments, the drying method further includes the following steps:

[0118] S40. The displacement solvent flowing from the acetylene container 1 to the vacuum pump 31 is condensed by the first condenser 52, and the displacement solvent recovered by the first condenser 52 is passed into the recovery tank 51 for collection.

[0119] In this embodiment, the displacement solvent vapor extracted from the acetylene container 1 by the vacuum pump 31 enters the first condenser 52, where it is liquefied after being cooled by the cooling medium. The liquefied displacement solvent then flows into the recovery tank 51 for collection.

[0120] The vaporized displacement solvent is condensed and then recovered for reuse, which reduces both treatment costs and environmental emissions. The displacement solvent is recyclable, making it both economical and environmentally friendly.

[0121] A complete displacement solvent condensation and recovery device was set up. The displacement solvent used in the process can be recovered, dried and purified and recycled, which greatly reduces the processing cost and reduces the consumption and emission of displacement solvent.

[0122] For example, the displacement solvent vapor drawn from the acetylene container 1 enters the first condenser 52, is cooled by cooling water (temperature ≤15°C) and liquefies into liquid displacement solvent, which then flows into the recovery tank 51. The recovery tank 51 collects a certain amount (e.g., the liquid level reaches a certain level) of displacement solvent and feeds it into the purification device.

[0123] Once no significant liquid flow occurs from the first condenser 52, continue vacuuming and heating in the heating chamber 21 for 0.5-2 hours to achieve deep drying. After drying, turn off the heating chamber 21 and vacuum pump 31, and fill the acetylene container 1 with dry nitrogen until positive pressure is reached. Test the moisture content inside the acetylene container 1. If the test is successful (e.g., moisture < 3 ppm), remove the acetylene container 1 from the mounting bracket 22 for later use.

[0124] For example, the moisture content of the gas inside acetylene container 1 was detected using a trace moisture analyzer, and the result was <3ppm, which meets the requirements for electronic grade acetylene.

[0125] In some embodiments, the drying method further includes the following steps:

[0126] S50. The displacement solvent discharged from the acetylene container 1 is heated by the preheater 73, and the heated displacement solvent is then introduced into the distillation column 71.

[0127] S60. The displacement solvent discharged from the distillation column 71 is passed into the molecular sieve fixed bed 42 for purification and then into the supply tank 41 for collection.

[0128] In this embodiment, the displacement solvent discharged from the acetylene container 1 (for example, the displacement solvent discharged from the acetylene container 1 into the recovery tank 51 can be discharged to the preheater 73 through the recovery tank 51, or the displacement solvent in the acetylene container 1 can be directly discharged to the preheater 73) is heated by the preheater 73 and then sent to the distillation column 71.

[0129] Distillation column 71 adopts micro-negative pressure distillation. The replacement solvent with water content <10ppm is collected from the top of the column and enters the supply tank 41 after passing the test.

[0130] Since the water removal capacity of distillation column 71 is limited, it can generally only remove water down to 10 ppm. Further dehydration relies on circulation through the molecular sieve fixed bed 42. The solvent after distillation is circulated through the molecular sieve fixed bed 42 for further dehydration, and then further dried to achieve a water content of <3 ppm. Once the water content is confirmed to be <3 ppm by online moisture detection, processing can be stopped and the solution is ready for use. The residual liquid discharged from the column bottom is sent to a waste liquid tank for centralized treatment.

[0131] The water content of the replacement solvent (e.g., acetone or ethanol) used must be <3 ppm to ensure that there is no secondary pollution caused by water carried by the solvent itself.

[0132] For example, the displacement solvent discharged from the distillation column 71 can be condensed and liquefied by the second condenser 72, and then passed into the molecular sieve fixed bed 42 for purification. That is, the distillation column 71 and the molecular sieve fixed bed 42 can be connected by the second condenser 72.

[0133] The distilled acetone is then passed through a 3A molecular sieve fixed bed 42 for further dehydration, and online moisture detection confirms that the water content is <3ppm. The recovered acetone can be recycled after being dried and dehydrated by the molecular sieve.

[0134] For example, when ethanol is used as the replacement solvent, cyclohexane is added to the recovered ethanol as an entrainer before being fed into an azeotropic distillation column. The azeotropic distillation column operates at atmospheric pressure, where cyclohexane and water form a minimum azeotrope that is distilled off from the top. The top temperature is controlled at 64-66°C, the bottom temperature at 78-80°C, and the reflux ratio at 3:1-6:1. Ethanol with a water content of approximately 10 ppm is obtained from the bottom. The azeotrope at the top is condensed and separated into phases; the upper cyclohexane layer is refluxed for recycling, while the lower aqueous phase is discharged. The distilled ethanol is then passed through a 3A molecular sieve fixed bed for deep dehydration, and online moisture detection confirms a water content of <3 ppm.

[0135] In some embodiments, the drying method further includes the following steps:

[0136] S10. Install the acetylene container 1 on the fixed frame 22. First, switch the pretreatment device 8 to the displacement mode and use the gas distribution platform to connect the acetylene container 1 to the inert gas source and the exhaust gas source respectively. Then, switch the pretreatment device 8 to the vacuum mode and use the gas distribution platform to connect the acetylene container 1 to the vacuum source.

[0137] In this embodiment, the acetylene container 1 is mounted on the mounting bracket 22 and vertically fixed in the heating box 21 with its opening facing upwards. The piping assembly is connected, and the airtightness of the system is checked. The residual acetylene gas in the acetylene container 1 is completely purged and replaced with inert gas, and then a vacuum is applied to the acetylene container 1. This ensures that there is no acetylene residue in the acetylene container 1 and guarantees operational safety.

[0138] For example, the residual acetylene gas in acetylene container 1 is purged, and then purged three times with 5N high-purity nitrogen.

[0139] Fix the acetylene container 1 in the heating box 21, connect all process pipelines, and perform a system airtightness check to ensure that the vacuum degree can reach below -0.095MPa.

[0140] In some embodiments, the replacement solvent is acetone or ethanol, and the water molecule content in the replacement solvent introduced into the acetylene container 1 by the supply device is <3ppm.

[0141] In this embodiment, acetone or ethanol has a strong ability to replace water molecules, thus achieving the replacement function.

[0142] When acetone is used as a solvent to dissolve acetylene in acetylene container 1, acetone can be used as the replacement solvent, which is the same as the original solvent in acetylene container 1. This avoids introducing new impurities into the container and ensures the purity requirements of electronic-grade acetylene.

[0143] The water molecule content in the replacement solvent in supply tank 41 is <3 ppm. A low-content (e.g., <3 ppm) water molecule replacement solvent (e.g., acetone or ethanol) is introduced into supply tank 41 to rinse the calcium silicate porous packing material inside the acetylene container 1. Through the diffusion, exchange, and dissolution of water molecules within the packing micropores, water molecules adsorbed deep within the packing micropores are displaced and carried out with the solvent. This solves the problem of deep removal of trace amounts of moisture from the packing micropores, effectively reducing the moisture content in the acetylene container 1 to below 3 ppm, achieving the ultra-low moisture content of 3 ppm required for electronic grade applications.

[0144] The following is an example of a drying method provided in this application.

[0145] Object to be treated: Acetylene container 1 is a 40L dissolved acetylene cylinder with a QF-15 valve, filled with porous calcium silicate packing. The moisture content inside the cylinder was tested to be approximately 250ppm.

[0146] Cylinder pretreatment (step S10): Empty the residual acetylene gas from the cylinder and purge it three times with 5N high-purity nitrogen. Fix the cylinder in the heating chamber 21, connect all process pipelines, and perform a system airtightness check to ensure that the vacuum degree can reach below -0.095MPa.

[0147] Solvent Injection and Rinsing (Step S20): Using ultra-dry acetone with a water content of 2.0 ppm as the rinsing solvent, acetone is injected into the steel cylinder through the third transfer pump 44, with the injection volume being 80% of the cylinder's internal volume. The cylinder is kept immersed for 4 hours to allow the acetone to fully penetrate into the micropores of the calcium silicate packing. After immersion, the steel cylinder is inverted using the fixing bracket 22 to drain the acetone.

[0148] Repeat the rinsing process: Repeat the injection-soaking-draining operation three times. The acetone discharged after the third rinse was found to have a water content below 3 ppm.

[0149] Negative pressure heating and drying (step S30): Close the tenth pipeline 610, start the vacuum pump 31, and evacuate the pressure inside the cylinder to below -0.095 MPa. Start the heating chamber 21 and heat the cylinder to 60±5℃. Maintain this temperature and vacuum for 7 hours to allow the acetone remaining in the micropores of the packing to completely vaporize and be extracted. Starting the vacuum pump 31 before starting the heating may extract a gas-liquid mixture during the extraction process, thus improving the evacuation efficiency.

[0150] Solvent condensation and recovery (step S40): Acetone vapor drawn from the cylinder enters the first condenser 52, where it is liquefied into liquid acetone after being cooled by cooling water (temperature ≤15℃) and flows into the recovery tank 51. The recovered acetone is heated to 85-95℃ by the preheater 73 and then sent to the distillation column 71. The distillation column 71 is a sieve tray column with 20-40 trays. The column operating pressure is -0.03~-0.01MPa (slight negative pressure). The distillate from the top of the column is cooled to 40-55℃ by the second condenser 72, with part being collected as product and part being refluxed back to the distillation column 71. The reflux ratio is controlled at 3:1-5:1. Under these conditions, acetone with a water content of approximately 8ppm can be obtained from the top of the column. The distilled acetone then flows through a 3A molecular sieve fixed bed 42 for deep dehydration, and online moisture detection confirms a water content of 2.0ppm. The recovered acetone can be recycled after being dried and dehydrated by the molecular sieve.

[0151] Deep drying and testing: After no liquid flows out of the first condenser 52, continue vacuum heating for 4 hours for deep drying. After completion, turn off the heating chamber 21 and vacuum pump 31, and fill with high-purity nitrogen to atmospheric pressure. The moisture content of the gas in the cylinder is detected using a trace moisture analyzer, and the result is 2.5 ppm, which meets the requirement of electronic-grade acetylene <3 ppm.

[0152] Processing complete: Remove the gas cylinder from the mounting bracket 22 and set it aside.

[0153] Treatment effect: After the above treatment, the moisture content in the cylinder decreased from 250 ppm to 2.5 ppm.

[0154] The following is a second embodiment of the drying method provided in this application.

[0155] Object of treatment: Acetylene container 1 is a seamless DOT steel cylinder, such as a CGA510 valve, a 47L dissolved acetylene cylinder, filled with porous calcium silicate packing. The moisture content inside the cylinder was tested to be approximately 180ppm.

[0156] Cylinder pretreatment (step S10): Same as in Example 1.

[0157] Solvent injection and rinsing (step S20): Use ultra-dry ethanol with a water content of 2.2 ppm as the rinsing solvent, injecting 80% of the cylinder's internal volume and soaking for 4 hours. After soaking, invert the cylinder to drain the ethanol. Repeat rinsing: Repeat the injection-soaking-draining operation 4 times.

[0158] Negative pressure heating and drying (step S30): Start vacuum pump 31 to pump to below -0.095MPa, heat to 60±5℃, and maintain for 7 hours.

[0159] Solvent condensation and recovery (step S40): The recovery method is the same as in Example 1. Cyclohexane is added to the recovered ethanol as an entrainer and fed into an azeotropic distillation column. The azeotropic distillation column operates at atmospheric pressure, and cyclohexane and water form a minimum azeotrope, which is distilled off from the top of the column. The top temperature is controlled at 64-66℃, the bottom temperature is controlled at 78-80℃, and the reflux ratio is controlled at 3:1-6:1. Ethanol with a water content of approximately 10 ppm is obtained from the bottom of the column. The azeotrope at the top of the column is condensed and separated into phases. The upper cyclohexane is refluxed for recycling, and the lower aqueous phase is discharged. The distilled ethanol is then passed through a 3A molecular sieve fixed bed 42 for deep dehydration, and online moisture detection confirms a water content of 2.2 ppm.

[0160] Deep drying and testing: Continue vacuum heating for 4 hours. The moisture content of the gas inside the cylinder was measured to be 2.4 ppm.

[0161] Processing complete: Remove the gas cylinder from the mounting bracket 22 and set it aside.

[0162] Treatment effect: After the above treatment, the moisture content in the cylinder decreased from 180 ppm before treatment to 2.4 ppm.

[0163] In some embodiments, the drying system can be fully automated through a PLC. The PLC is electrically connected to the heating device, extraction device, supply device, recovery device, purification device, and pretreatment device 8, respectively, and is used to automatically control the start-up, shutdown, switching, and parameter adjustment of each device according to a preset program.

[0164] For example, the PLC control includes: automatically controlling the start and stop of the third transfer pump 44 and the metering of the flow meter 45 to achieve quantitative injection of the replacement solvent; automatically controlling the flipping action of the fixing frame 22 to achieve automatic flipping and drainage of the acetylene container 1; automatically controlling the start and stop of the vacuum pump 31 and vacuum detection to achieve automatic establishment and maintenance of a negative pressure environment; automatically controlling the heating temperature and heating time of the heating box 21; automatically controlling the condensation temperature of the first condenser 52 and the second condenser 72; automatically controlling the operating pressure and reflux ratio of the distillation column 71; and automatically controlling the switching of the pretreatment device 8 between replacement mode and vacuum mode. Through the full-process automated control of the PLC, it is suitable for the standardized processing of large batches of electronic-grade acetylene cylinders, improving processing efficiency and consistency.

[0165] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0166] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0167] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0168] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A drying system, characterized in that, The drying system is used for drying acetylene containers and includes: A heating device for mounting the acetylene container and heating the acetylene container; An extraction device, which is connected to the acetylene container, is used to evacuate the acetylene container; The drying system further includes a supply device, which is configured to: introduce a displacement solvent into the acetylene container through the supply device, and after the displacement solvent replaces the water molecules in the acetylene container, discharge the displacement solvent.

2. The drying system as described in claim 1, characterized in that, The drying system also includes a recovery device and a piping assembly. The recovery device includes a recovery tank and a first condenser. The piping assembly includes a first pipe and a second pipe. The first pipe connects the acetylene container to the recovery tank, and the second pipe connects the acetylene container to the first condenser. The first condenser is connected to the recovery tank.

3. The drying system as described in claim 2, characterized in that, The extraction device includes a vacuum pump, and the first condenser connects the vacuum pump to the acetylene container.

4. The drying system as described in claim 3, characterized in that, The piping assembly includes a fourth pipe that connects the first condenser to the vacuum pump, and the extraction device further includes a buffer tank disposed on the fourth pipe.

5. The drying system as described in claim 2, characterized in that, The drying system also includes a purification device, which includes a distillation column and a second condenser. The piping assembly includes a fifth pipeline and a sixth pipeline. The fifth pipeline connects the recovery tank to the distillation column, and the sixth pipeline connects the second condenser to the supply device. The distillation column is connected to the second condenser.

6. The drying system as described in claim 5, characterized in that, The purification apparatus further includes a preheater, which is located on the fifth pipeline to heat the displacement solvent flowing from the recovery tank into the distillation column.

7. The drying system as described in claim 5, characterized in that, The supply device includes a supply tank and a molecular sieve fixed bed. The sixth pipeline connects the second condenser to the supply tank, and the molecular sieve fixed bed is disposed on the sixth pipeline.

8. The drying system as described in claim 7, characterized in that, The piping assembly also includes a ninth pipe that connects the supply tank to the molecular sieve fixed bed, so that the supply tank and the molecular sieve fixed bed form a circulation loop.

9. The drying system as described in claim 7, characterized in that, The piping assembly also includes a tenth pipeline that connects the supply tank to the acetylene container. The supply device also includes a third delivery pump and a flow meter, both of which are located on the tenth pipeline.

10. The drying system as claimed in claim 1, characterized in that, The heating device includes a heating box and a fixing frame. The acetylene container is located inside the heating box and is connected to the fixing frame. The fixing frame is configured to drive the acetylene container to rotate.

11. The drying system as claimed in claim 1, characterized in that, The drying system also includes a pretreatment device, which includes a gas distribution platform. The pretreatment device has a displacement mode and a vacuum mode. In the displacement mode, the gas distribution platform connects the acetylene container to an inert gas source and a tail gas source, respectively. In the vacuum mode, the gas distribution platform connects the acetylene container to a vacuum source.

12. A drying method for a drying system according to any one of claims 1 to 11, characterized in that, Includes the following steps: The displacement solvent is introduced into the acetylene container through the supply device. After the displacement solvent replaces the water molecules in the acetylene container, the displacement solvent is discharged. The extraction device is activated to evacuate the acetylene container, and the heating device is activated to heat the acetylene container.

13. The drying method according to claim 12, characterized in that, The drying method further includes the following steps: The displacement solvent flowing from the acetylene container to the vacuum pump is condensed by a first condenser, and the displacement solvent recovered by the first condenser is passed into a recovery tank for collection.

14. The drying method as described in claim 12, characterized in that, The drying method further includes the following steps: The displacement solvent discharged from the acetylene container is heated using a preheater, and the heated displacement solvent is then passed into a distillation column. The displacement solvent discharged from the distillation column is purified by passing it through a molecular sieve fixed bed and then collected in a supply tank.

15. The drying method as described in claim 12, characterized in that, The drying method further includes the following steps: The acetylene container is installed on the fixed frame. First, the pretreatment device is switched to the displacement mode. The acetylene container is connected to the inert gas source and the exhaust gas source respectively using the gas distribution platform. Then, the pretreatment device is switched to the vacuum mode. The acetylene container is connected to the vacuum source using the gas distribution platform.

16. The drying method according to claim 12, characterized in that, The replacement solvent is acetone or ethanol, and the water molecule content in the replacement solvent introduced into the acetylene container by the supply device is <3ppm.

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