Hydrogen fluoride production system and production method

Abstract

The invention provides a hydrogen fluoride production system and method, and belongs to the technical field of hydrogen fluoride production, the hydrogen fluoride production system comprises a reaction unit, a purification unit and a rectification unit which are arranged in sequence, and the rectification unit comprises a rectification tower, a first cooler, a second cooler and a cold crude acid tank; the first cooler is provided with a first cooling medium channel and a first working medium channel, and an inlet of the first working medium channel communicates with an outlet of the purification unit; the second cooler is provided with a second cooling medium channel and a second working medium channel, an inlet of the second working medium channel is communicated with an outlet of the first working medium channel, an outlet of the first working medium channel is communicated with an inlet of the second working medium channel, and an outlet of the first cooling medium channel is communicated with the rectifying tower; according to the invention, the liquid hydrogen fluoride is stored in the cold crude acid tank, so that the liquid hydrogen fluoride cools the gaseous hydrogen fluoride in the first cooler, a coolant does not need to be purchased or supplemented, and the production cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen fluoride processing, and in particular to a hydrogen fluoride production system and a production method. Background Art

[0002] Hydrogen fluoride (HF) is an inorganic compound with the chemical formula HF. It is a colorless, toxic, and highly irritating gas. Hydrogen fluoride is a gas at room temperature and pressure with a pungent odor. It reacts with water and almost all organic matter. In industry, fluorspar and sulfuric acid are commonly used to produce hydrogen fluoride.

[0003] Chinese patent document CN113321185B discloses a process for producing anhydrous hydrogen fluoride, comprising the following steps: step 1, feeding fluorite powder into a hydrogen fluoride reactor; step 2, passing the mixed acid solution in the mixed acid tank into the hydrogen fluoride reactor through a pre-reactor; step 3, reacting to generate calcium sulfate and hydrogen fluoride gas; step 4, the gaseous product of the hydrogen fluoride reactor first enters a pre-washing tower and a pre-purification tower for dust removal and cooling, and then enters an F primary condenser and a P secondary condenser in sequence; step 5, returning the condensate obtained in the F primary condenser to the pre-purification tower; the condensate obtained in the HF secondary condenser enters a distillation tower; and step 6, the overhead distillate in the distillation tower enters a finished product cooler to remove light components such as SO2 and SiF4.

[0004] However, the production and processing technology in the existing technology only has two levels of cooling for hydrogen fluoride processing, namely F primary condenser and P secondary condenser. The cooling requires additional coolant, which needs to be purchased, stored and transported, thereby increasing production costs. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defect in the prior art process flow that the cooling process of hydrogen fluoride gas requires the purchase of additional coolant, thereby providing a hydrogen fluoride production system and production method.

[0006] In order to solve the above technical problems, the present invention provides a hydrogen fluoride production system, comprising: a reaction unit, a purification unit and a distillation unit arranged in sequence, wherein the distillation unit comprises:

[0007] distillation tower;

[0008] a first cooler having a first cooling medium channel and a first working medium channel, wherein the inlet of the first working medium channel is connected to the outlet of the purification unit, the gaseous material outlet of the first working medium channel is connected to the inlet of the second cooler, and the first outlet of the first cooling medium channel is connected to the distillation tower;

[0009] a second cooler having a second cooling medium channel and a second working medium channel, wherein an inlet of the second working medium channel is connected to an outlet of the first working medium channel of the first cooler;

[0010] The cold crude acid tank has a first inlet and a second inlet, the first inlet is connected to the liquid material outlet of the first working medium channel of the first cooler, the second inlet is connected to the outlet of the second working medium channel of the second cooler, and the outlet of the cold crude acid tank is connected to the inlet of the first cooling medium channel of the first cooler.

[0011] Preferably, the outlet of the cold crude acid tank is also connected to the purification unit.

[0012] Preferably, the cold coarse acid tank comprises: a first cold coarse acid tank and a second cold coarse acid tank, and the first cold coarse acid tank and the second cold coarse acid tank are connected.

[0013] Preferably, the distillation tower has a first outlet and a second outlet, the first outlet is connected to the purification unit, and the second outlet is connected to the inlet of the degassing tower;

[0014] Alternatively, the first outlet is communicated with an inlet of a first cooling medium channel of the first cooler, and a second outlet of the first cooling medium channel is communicated with the purification unit.

[0015] Preferably, the degassing tower has a first outlet and a second outlet, the first outlet is communicated with the inlet of the working medium channel of the second cooler, and the second outlet is communicated with the finished product tank.

[0016] Preferably, the second working medium channel of the second cooler has a gaseous material outlet, which is sequentially connected to a sulfuric acid absorption device, a three-stage water washing device, a negative pressure fan and an exhaust gas treatment unit, and the sulfuric acid absorption device is also connected to the purification unit.

[0017] Preferably, the purification unit comprises: a first purification tower and a second purification tower, the first purification tower is connected to the pickling absorption device, and the outlet of the first purification tower is connected to the second purification tower through a first pipeline.

[0018] Preferably, the reaction unit comprises: an external mixer and a reaction furnace, the outlet of the external mixer is connected to the reaction furnace, and the inlet of the external mixer is connected to a fluorite powder feeding mechanism and an acid feeding mechanism, respectively.

[0019] Preferably, the fluorite powder feeding mechanism includes a fluorite silo, the outlet of the fluorite silo is connected to a loss-in-weight scale via a star feeder, and the outlet of the loss-in-weight scale is connected to the external mixer.

[0020] Preferably, the acid feeding mechanism comprises an acid mixing tank, the outlet of the acid mixing tank is connected to the external mixer, and the inlet of the acid mixing tank is respectively connected to at least one acid solution.

[0021] Preferably, the outlet of the reaction furnace is connected to a slag cooler, and the outlet of the slag cooler is connected to a gypsum silo.

[0022] In addition, a method for producing hydrogen fluoride is also provided, which adopts the hydrogen fluoride production system described in any one of the above schemes, comprising the following steps:

[0023] generating hydrogen fluoride gas through a reaction unit;

[0024] The hydrogen fluoride gas is subjected to dust removal, water removal, heavy component removal and sulfur removal through a purification unit;

[0025] The hydrogen fluoride gas is further purified by a distillation unit.

[0026] Preferably, the hydrogen fluoride gas is cooled by a first cooler after being output from the purification unit, and then at least a portion of the hydrogen fluoride gas is transported to a distillation tower, and the remaining portion of the gas after being purified by the distillation tower is returned to the purification unit;

[0027] After being cooled by the first cooler, part of the hydrogen fluoride gas is transported to the second cooler, and the hydrogen fluoride gas is further cooled into a liquid state by the second cooler, and then transported to the cold crude acid tank, and the liquid hydrogen fluoride in the cold crude acid tank is used to cool the hydrogen fluoride gas in the first cooler.

[0028] Preferably, the second cooler has a gaseous material outlet, through which the gaseous material is discharged, and then absorbed by the sulfuric acid absorption device and then refluxed into the purification unit.

[0029] Preferably, in the reaction unit, before the fluorite powder is transported to the reaction furnace, it is first mixed with an acid solution in an external mixer, wherein the weight ratio of powder to acid is 1:1.18-1:1.25.

[0030] Preferably, before the fluorite powder is conveyed to the external mixer, the fluorite powder is first dried so that the moisture content of the fluorite powder is not greater than 0.1%. The dried fluorite powder is conveyed to a weighing platform through a spiral device, and then conveyed to the external mixer after weighing.

[0031] Preferably, the purification unit includes a first purification tower and a second purification tower, wherein sulfuric acid is sprayed in the first purification tower to react with dust and water in the hydrogen fluoride gas to remove dust and moisture; in the second purification tower, the liquid hydrogen fluoride returned from the distillation tower cools the second purification tower, and the impurities are cooled into liquid form, and the liquid impurities flow back into the first purification tower from the bottom of the second purification tower.

[0032] The technical solution of the present invention has the following advantages:

[0033] 1. In the hydrogen fluoride production system provided by the present invention, gaseous hydrogen fluoride from the purification unit enters the first working medium channel of the first cooler, and then partially condensed liquid hydrogen fluoride enters the cold crude acid tank through the liquid material outlet of the first working medium channel. Uncondensed gaseous hydrogen fluoride enters the second cooler for further cooling. The liquid hydrogen fluoride cooled in the second working medium channel of the second cooler enters the cold crude acid tank. The liquid hydrogen fluoride in the cold crude acid tank enters the first cooling medium channel to cool the gaseous hydrogen fluoride in the first working medium channel. By providing a cold crude acid tank to store liquid hydrogen fluoride, the liquid hydrogen fluoride cools the gaseous hydrogen fluoride in the first cooler, thereby eliminating the need to purchase or replenish coolant and reducing production costs.

[0034] 2. The hydrogen fluoride production system provided by the present invention returns liquid low-temperature hydrogen fluoride, which vaporizes when heated, thereby lowering the temperature of the purification tower. As the temperature decreases, high-boiling-point impurities change from gas to liquid, thereby improving the purity of the hydrogen fluoride gas in the purification unit.

[0035] 3. The hydrogen fluoride production system provided by the present invention can ensure the continuous supply of liquid hydrogen fluoride by providing the first cold crude acid tank and the second cold crude acid tank, thereby avoiding the production interruption problem caused by insufficient liquid hydrogen fluoride.

[0036] 4. The hydrogen fluoride production system provided by the present invention connects the first outlet of the distillation tower with the purification unit, so that hydrogen fluoride containing some impurities is transported to the purification unit for recirculation, thereby improving the utilization of hydrogen fluoride; and connects the second outlet of the distillation tower with the degassing tower, so that the high-purity hydrogen fluoride from the distillation tower is further purified in the degassing tower.

[0037] 5. The hydrogen fluoride production system provided by the present invention connects the first outlet of the degassing tower with the inlet of the second working medium channel of the second cooler, so that the hydrogen fluoride containing impurities in the degassing tower is re-purified. By connecting the second outlet of the degassing tower with the finished product tank, high-purity hydrogen fluoride enters the finished product tank for storage.

[0038] 6. The hydrogen fluoride production system provided by the present invention has a gaseous material outlet provided on the second working medium channel of the second cooler. The hydrogen fluoride in the gaseous material outlet is absorbed by a sulfuric acid absorption device to improve the utilization rate of the hydrogen fluoride. Byproducts are generated by a three-stage water washing device, thereby improving the production efficiency of the entire system. The sulfur dioxide in the exhaust gas is absorbed by a negative pressure fan and an exhaust gas treatment unit to prevent the sulfur dioxide from being discharged into the atmosphere.

[0039] 7. The hydrogen fluoride production system provided by the present invention is configured with a purification unit consisting of a first purification tower and a second purification tower. The first purification tower performs preliminary removal of dust and other impurities in the generated hydrogen fluoride gas to reduce the impurity content of the hydrogen fluoride gas. The second purification tower removes heavy components, sulfur, and water from the hydrogen fluoride gas to further reduce the impurity content of the hydrogen fluoride gas and ensure that the hydrogen fluoride gas reaches a high purity standard.

[0040] 8. The hydrogen fluoride production system provided by the present invention comprises a reaction unit comprising: an external mixer and a reactor. The external mixer is used to perform a preliminary reaction on fluorite powder and mixed acid, so that the fluorite powder and mixed acid are fully mixed and pre-reacted to generate preliminary hydrogen fluoride gas; the reactor is used to heat the fluorite powder and mixed acid to achieve further reaction, thereby achieving efficient production of hydrogen fluoride gas.

[0041] 9. The hydrogen fluoride production system provided by the present invention improves the precise control of the weight of fluorite powder through the star-shaped feeder, ensures the weight of the fluorite powder transported to the loss-in-weight scale, and plays a role in uniform and quantitative feeding.

[0042] 10. The hydrogen fluoride production system provided by the present invention mixes 98 acid and 105 acid through a mixed acid tank so that the mixed acid reaches a suitable concentration and ratio to meet the requirements of the reaction with fluorite powder, thereby improving the efficiency of the reaction between the acid and fluorite powder.

[0043] 11. The hydrogen fluoride production system provided by the present invention cools the waste slag in the reaction furnace through a slag cooler, and stores the gypsum in a gypsum silo after cooling. The gypsum is used as a solid by-product, thereby improving the resource utilization rate of the entire production system.

[0044] 12. The hydrogen fluoride production method provided by the present invention adopts the hydrogen fluoride production system of the above scheme, cools the hydrogen fluoride gas into hydrogen fluoride liquid, and uses the hydrogen fluoride liquid to cool the hydrogen fluoride gas, thereby reducing the use of coolant. At the same time, the hydrogen fluoride is repeatedly circulated and purified, thereby improving the purification efficiency of the system.

[0045] 13. The hydrogen fluoride production method provided by the present invention comprises the following steps: a portion of the hydrogen fluoride gas is output from the first cooler to the second cooler, further cooled by the second cooler, and then the hydrogen fluoride is output from the second cooler as liquid hydrogen fluoride and transported to a cold crude acid tank; the other portion of the material containing impurities is returned to the purification unit for further removal of impurities.

[0046] 14. The hydrogen fluoride production method provided by the present invention absorbs hydrogen fluoride at the outlet of the gaseous material by sulfuric acid, thereby reducing the waste of hydrogen fluoride, recovering the hydrogen fluoride, and reflowing it into the purification unit for purification.

[0047] 15. The hydrogen fluoride production method provided by the present invention achieves fine control of the hydrogen fluoride production process by adjusting the ratio of fluorite powder to sulfuric acid, further improving the production efficiency and product weight of hydrogen fluoride.

[0048] 16. The hydrogen fluoride production method provided by the present invention reduces the water content in the fluorite powder by drying the fluorite powder, thereby reducing the water content in the hydrogen fluoride in the subsequent steps and avoiding corrosion to the production equipment.

[0049] 17. The hydrogen fluoride production method provided by the present invention uses a first purification tower to absorb dust and water in the hydrogen fluoride, thereby initially reducing the impurity content in the hydrogen fluoride. The second purification tower further absorbs and removes heavy metal impurities and elemental sulfur in the hydrogen fluoride, thereby greatly reducing the impurity content in the hydrogen fluoride. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0051] Figure 1 A front view of a hydrogen fluoride production system provided in one embodiment of the present invention;

[0052] Figure 2 for Figure 1 The main view of the second purification tower in FIG;

[0053] Figure 3 for Figure 1 A cross-sectional view of the reactor in FIG.

[0054] Figure 4 for Figure 1 A cross-sectional view of the slag pushing spiral device in FIG.

[0055] Description of reference numerals:

[0056] 1. Second purification tower; 2. Anti-slag spiral device; 3. Cleaning blade; 4. First spiral stirring blade; 5. Second spiral stirring blade; 6. Feed hopper; 7. Air guide pipe; 8. Slag pushing spiral. DETAILED DESCRIPTION

[0057] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0058] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0059] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0060] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0061] The hydrogen fluoride production system and production method provided in this embodiment are used to produce hydrogen fluoride from low-grade fluorspar and sulfuric acid.

[0062] like Figure 1As shown, a specific implementation of the hydrogen fluoride production system provided in this embodiment is provided, which is arranged in sequence: a reaction unit, a purification unit and a distillation unit, the reaction unit is connected to the purification unit, and the purification unit is connected to the distillation unit. The reaction unit produces hydrogen fluoride gas by reacting fluorite powder with sulfuric acid, and the generated hydrogen fluoride gas enters the purification unit. The purification unit preliminarily removes various impurities and water contained in the hydrogen fluoride gas, and the hydrogen fluoride gas with preliminarily removed impurities enters the distillation unit for further purification. The distillation unit includes: a distillation tower, a first cooler, a second cooler and a cold crude acid tank. The first cooler has a first cooling medium channel and a first working medium channel, and the first working medium channel has a gas phase material outlet and a liquid phase material outlet. The inlet of the first working medium channel is connected to the outlet of the purification unit, and the gaseous outlet of the first working medium channel is connected to the inlet of the second cooler; the second cooler has a second cooling medium channel and a second working medium channel, and the inlet of the second working medium channel is connected to the outlet of the first working medium channel of the first cooler; the cold crude acid tank has a first inlet and a second inlet, the first inlet is connected to the liquid material outlet of the first working medium channel of the first cooler, the second inlet is connected to the outlet of the second working medium channel of the second cooler, and the outlet of the cold crude acid tank is connected to the inlet of the second working medium channel of the first cooler.

[0063] The gaseous hydrogen fluoride of the purification unit enters the first working medium channel of the first cooler, and then the partially condensed liquid hydrogen fluoride enters the cold crude acid tank through the liquid phase material outlet of the first working medium channel. The uncondensed gaseous hydrogen fluoride enters the second cooler for further cooling. The liquid hydrogen fluoride cooled in the second working medium channel of the second cooler enters the cold crude acid tank. The liquid hydrogen fluoride in the cold crude acid tank enters the first cooling medium channel to cool the gaseous hydrogen fluoride in the first working medium channel. The second cooler cools the hydrogen fluoride gas into liquid hydrogen fluoride, which enters the cold crude acid tank. The liquid hydrogen fluoride in the cold crude acid tank enters the first cooling medium channel of the first cooler to cool the gaseous hydrogen fluoride in the first working medium channel of the first cooler. At this time, the liquid hydrogen fluoride in the first cooling medium channel absorbs heat, and the hydrogen fluoride gas in the first working medium channel releases heat to further lower the temperature.

[0064] Specifically, the fluorite powder is low-grade fluorite with a mesh size of 500. The low-grade fluorite contains a high amount of impurities, including a high sulfur content and a calcium fluoride content of more than 80%. The temperature of the hydrogen fluoride gas discharged from the purification unit is 30°. The temperature of the hydrogen fluoride gas after cooling through the first cooler is 20°. The temperature of the 20° hydrogen fluoride gas after cooling through the second cooler is 10°, at which time the hydrogen fluoride gas is cooled into a liquid. The temperature of the hydrogen fluoride liquid in the cold crude acid tank is 10°. The hydrogen fluoride liquid in the cold crude acid tank passes through the first cooling medium channel of the first cooler to cool the hydrogen fluoride gas in the first cooling working medium channel, and then the hydrogen fluoride liquid in the first cooling medium channel flows back into the cold crude acid tank. The hydrogen fluoride liquid at the outlet of the second cooler enters the cold crude acid tank to replenish the hydrogen fluoride liquid.

[0065] By storing liquid hydrogen fluoride in a cold crude acid tank, the liquid hydrogen fluoride cools the gaseous hydrogen fluoride in the first cooler, eliminating the need to purchase or replenish coolant and reducing production costs. Furthermore, using the liquid hydrogen fluoride in the cold crude acid tank as the cooling medium not only effectively utilizes resources but also avoids the environmental pollution associated with traditional coolants. Furthermore, this design simplifies and improves the cooling process, enhancing the operational stability and efficiency of the entire hydrogen fluoride production system.

[0066] like Figure 1 As shown, an implementation method provided by this embodiment, the outlet of the first cooling medium channel of the first cooler is also connected to the purification unit, and at this time, liquid hydrogen fluoride enters the purification unit to cool the gaseous hydrogen fluoride in the purification unit, thereby reducing the temperature of the hydrogen fluoride gas discharged from the purification unit. By returning the liquid low-temperature hydrogen fluoride, the liquid hydrogen fluoride vaporizes when heated, and the temperature of the purification tower is reduced to 30 °. As the temperature decreases, the high-boiling point impurities are converted from gas to liquid, thereby improving the purity of the hydrogen fluoride gas in the purification unit. It should be noted that, as an alternative implementation method, the outlet in the cold crude acid tank can be connected to the purification unit.

[0067] like Figure 1As shown, a method for implementing the present embodiment, the cold rough acid tank includes: a first cold rough acid tank and a second cold rough acid tank, wherein the first cold rough acid tank and the second cold rough acid tank are connected. The first inlet of the first cold rough acid tank is connected to the first cooling medium channel of the first cooler. The second inlet of the first cold rough acid tank is connected to the first outlet of the second cold rough acid tank. The inlet of the second cold rough acid tank is connected to the second working medium channel of the second cooler. The liquid hydrogen fluoride from the second cooler enters the second cold rough acid tank for storage. When the liquid hydrogen fluoride in the first cold rough acid tank is consumed, the first cold rough acid tank is replenished by the second cold rough acid tank. By providing the first cold rough acid tank and the second cold rough acid tank, a continuous supply of liquid hydrogen fluoride can be ensured, thereby avoiding the problem of production interruption caused by insufficient liquid hydrogen fluoride. When the liquid hydrogen fluoride in the first cold rough acid tank is consumed to a certain amount, the liquid hydrogen fluoride in the second cold rough acid tank will automatically flow into the first cold rough acid tank, achieving automatic replenishment, improving production efficiency, and reducing the tedious manual operation. At the same time, the connection design of the first cold crude acid tank and the second cold crude acid tank further improves the cooling effect and the purity of hydrogen fluoride. It should be noted that, as an alternative embodiment, only one cold crude acid tank can be provided, that is, only the first cold crude acid tank is provided, and the import of the first cold crude acid tank is respectively communicated with the first cooling medium channel of the first cooler and the first cooling medium channel of the second cooler. In addition, as an alternative embodiment, the outlet of the second cold crude acid tank can also be communicated with a distillation tower, so that the hydrogen fluoride liquid enters the distillation tower to remove impurities.

[0068] like Figure 1 As shown, an implementation method provided in this embodiment is provided, in which the distillation tower has a first outlet and a second outlet, the first outlet is connected to the purification unit, and the second outlet is connected to the inlet of the degassing tower. The liquid hydrogen fluoride is vaporized in the first cooling channel of the first cooler and enters the lower part of the distillation tower in the form of gas phase. After entering the distillation tower, the gas rises to the cooler at the upper end of the distillation tower, and part of the hydrogen fluoride becomes liquid hydrogen fluoride. The liquid hydrogen fluoride flows into the bottom of the tower, and the gaseous hydrogen fluoride containing impurities enters the purification unit at the top of the distillation tower to re-participate in the circulation, and the high-purity hydrogen fluoride enters the degassing tower. By setting the first outlet to be connected to the purification unit and setting the second outlet to be connected to the degassing tower, the high-purity hydrogen fluoride enters the degassing tower for further purification, and the hydrogen fluoride gas containing impurities enters the purification unit to re-participate in the purification cycle. It should be noted that, as an alternative implementation method, the distillation tower can also be provided with a third outlet, and the third outlet is connected to the second working medium channel of the second cooler.

[0069] Alternatively, as an alternative embodiment, the first outlet of the distillation tower is connected to the inlet of the first cooling medium channel of the first cooler, and the outlet of the first cooling medium channel is connected to the purification unit. In this case, hydrogen fluoride containing impurities in the distillation tower enters the first cooling medium channel. If the hydrogen fluoride in the first cooling medium channel enters the purification unit, the purification unit processes the impurities in the hydrogen fluoride. If the hydrogen fluoride in the first cooling medium channel enters the distillation tower, the impurities are removed again in the distillation tower.

[0070] like Figure 1 As shown, an embodiment provided in this embodiment, the degassing tower has a first outlet and a second outlet, the first outlet is connected to the inlet of the second working medium channel of the second cooler, and the second outlet is connected to the finished product tank. The degassing tower is mainly used to remove gaseous impurities dissolved in hydrogen fluoride solution or products. A cooler is provided at the top of the degassing tower. By controlling the temperature of the top of the tower, the hydrogen fluoride at the bottom of the tower is gaseous. After a part of the gaseous hydrogen fluoride rises, it encounters the cooler and becomes liquid hydrogen fluoride. The liquid hydrogen fluoride enters the finished product tank, and the hydrogen fluoride containing impurities enters the second working medium channel of the second cooler. By setting the degassing tower, the hydrogen fluoride in the distillation tower is further purified to remove excess impurities. It should be noted that, as an alternative embodiment, the degassing tower can also be provided with a third outlet, and the third outlet is connected to the second purification tower 1.

[0071] like Figure 1 The figure shows an embodiment of this embodiment. The second working medium channel of the second cooler has a gaseous material outlet, which is sequentially connected to a sulfuric acid absorption unit, a three-stage water scrubber, a negative pressure blower, and an exhaust gas treatment unit. The sulfuric acid absorption unit is also connected to the purification unit. The sulfuric acid absorption unit primarily uses 98% acid to absorb hydrogen fluoride. After absorbing hydrogen fluoride, the 98% acid enters the pre-purification tower. The sulfuric acid absorption unit is used to absorb hydrogen fluoride gas discharged from the gaseous material outlet and recycle the hydrogen fluoride. After treatment in the sulfuric acid absorption unit, the gas mainly includes silicon tetrafluoride, phosphorus pentafluoride, and sulfur dioxide. The gas enters the three-stage water scrubber to produce silicofluoric acid and phosphoric acid. The sulfur dioxide gas then passes through the negative pressure blower and enters the exhaust gas treatment unit for final treatment and discharge to ensure that the discharged gas is harmless to the environment. The connection design between the sulfuric acid absorption unit and the purification unit allows the acidic solution or other valuable substances produced during the absorption process to flow back into the purification unit and re-enter the hydrogen fluoride purification cycle, thereby improving resource utilization and overall system efficiency. It should be noted that, as an alternative embodiment, the gas-phase material outlet is provided with a valve for controlling the opening and closing of the gas-phase material outlet.

[0072] Specifically, the inlet of the second cooling medium channel of the second cooler is a 35% ethylene glycol solution with a temperature of -5°, and the ethylene glycol solution cools the hydrogen fluoride in the second working medium channel.

[0073] like Figure 1 As shown, this is an implementation method provided by this embodiment. The purification unit includes: a first purification tower and a second purification tower 1. The first purification tower is connected to the pickling absorption device, and the outlet of the first purification tower is connected to the second purification tower 1 through a first pipeline. The first purification tower is a pre-purification tower that removes dust and water generated by hydrogen fluoride gas. 98 acid is sprayed downward from the top of the first purification tower using sulfuric acid. 98 acid absorbs dust and moisture, thereby reducing impurities in the hydrogen fluoride gas. The function of the second purification tower 1 is to remove heavy components, sulfur and water. Specifically, the liquid hydrogen fluoride from the cold crude acid tank enters the first cooling medium channel of the first cooler. The outlet of the first cooling medium channel is connected to the second purification tower. The liquid hydrogen fluoride in the first cooling medium channel enters the second purification tower. The liquid hydrogen fluoride vaporizes when heated, reducing the temperature of the purification tower to 30°. As the temperature decreases, the high-boiling-point impurities change from gas to liquid and flow back to the pre-purification system from the bottom of the tower. It should be noted that, as an alternative embodiment, the outlet of the second purification tower 1 is connected to the inlet of the first purification tower through a second pipe, so that the hydrogen fluoride containing impurities in the second purification tower 1 enters the first purification tower for dust and water removal.

[0074] Specifically, the sublimation temperature of elemental sulfur is between 90-120°C, and it exists in the form of sulfur vapor in the high-temperature reactor system. The sublimation temperature of sulfur is around 75°C. In the pre-purification tower, purification tower, and condenser, as the system temperature drops, it will gradually precipitate and adhere to the packing, equipment, and pipelines. Sulfur vapor enters the first purification tower and the second purification tower 1 along with the HF gas generated by the reaction. The second purification tower 1 is a packed tower. High-temperature hydrogen fluoride gas enters from the bottom of the tower and contacts the liquid hydrogen fluoride from the cold crude acid tank at the top of the tower in reverse. The liquid hydrogen fluoride in the cold crude acid tank absorbs heat and becomes gaseous hydrogen fluoride. As the temperature of the hydrogen fluoride in the second purification tower 1 drops, sulfur precipitates in large quantities in the second purification tower 1, and the gaseous sulfur is converted into solid sulfur, which adheres to the packing.

[0075] When the outlet temperature of the second purification tower 1 is reduced to below 30°, the sulfur can be controlled to precipitate in the purification tower without participating in the subsequent process flow. At the same time, lowering the outlet temperature of the second purification tower 1 requires a large amount of return (that is, returning the liquid hydrogen fluoride in the cold crude acid tank to the second purification tower 1). Too much return will cause a large amount of system gas volume. To avoid a large amount of return, the purification inlet temperature needs to be reasonably controlled. The inlet temperature of the purification tower is controlled at 80-90° to prevent water vapor from entering the second purification tower (assuming that water vapor enters the second purification tower and turns into water in the purification tower, releasing a large amount of heat).

[0076] like Figure 2 As shown, the second purification tower 1 adopts a three-layer packing type:

[0077] The first layer is the top layer:

[0078] ①. PTFE ball rings Ø76*76*5 are neatly stacked in three layers; (Ø76: outer diameter 76 mm (diameter of the filler body). 76: height 76 mm (vertical height of the filler unit). 5: wall thickness 5 mm).

[0079] ②、PTFE ball ring Ф50*50*4 in bulk.

[0080] Second layer (middle layer)

[0081] ①, PTFE ball rings Ф76*76*5 are neatly stacked in three layers;

[0082] ②、PTFE ball ring Ф50*50*4 in bulk.

[0083] Third floor (bottom floor)

[0084] ①、PTFE Raschig rings Ф100*100*8 are neatly stacked.

[0085] In order to ensure that all sulfur is precipitated in the second purification tower 1 and to increase the residence time of sulfur in the second purification tower 1 as much as possible, the design flow rate adopted in this embodiment is 10-15 m / s, wherein the diameter of the third layer (bottom layer) is larger than that of the second layer and the first layer, and the area of ​​the first layer is increased to facilitate the deposition of sulfur on the third layer (bottom layer).

[0086] Two groups of first and second purification towers 1 are provided. While the first group is in process, the second group is not. If the pressure differential between the inlet and outlet of the second purification tower 1 exceeds 2 kPa during production, indicating blockage within the second purification tower 1, the first group is closed and the second group is opened to clean sulfur from the inner walls of the first and second purification towers 1 to ensure continuous production.

[0087] like Figure 1As shown, an implementation method provided by this embodiment, the reaction unit includes: an external mixer and a reactor, and the outlet of the external mixer is connected to the reactor. The inlet of the external mixer is respectively connected to the fluorite powder feeding mechanism and the acid feeding mechanism, and its main function is to fully mix the fluorite powder and the acid solution so that the two raw materials achieve a preliminary uniform distribution before entering the reactor, creating good conditions for the subsequent chemical reaction in the reactor. In the reactor, the fluorite powder reacts chemically with the acid solution to generate by-products such as hydrogen fluoride gas and calcium sulfate. The outlet of the reactor is connected to a slag cooler, and the high-temperature waste after the reaction enters the slag cooler for cooling treatment. It should be noted that, as a replaceable implementation method, it can also include: a heating device, which is arranged below the reactor to heat the reactor to ensure that hydrogen fluoride production proceeds smoothly.

[0088] Specifically, the fluorite powder feeding mechanism includes: a fluorite conveying screw, which is arranged at an angle to the external mixer, and the height of the input end of the fluorite conveying screw is lower than the height of the output end to avoid fluorite powder impact.

[0089] like Figure 1 As shown, an implementation method provided by this embodiment, the fluorite powder feeding mechanism includes a fluorite silo, and the outlet of the fluorite silo is connected to a loss-in-weight scale via a star feeder, and the outlet of the loss-in-weight scale is connected to an external mixer, which plays a role in uniform and quantitative feeding, and conveys the fluorite powder in the fluorite silo to the loss-in-weight scale at a certain rate. The rotation speed of the star feeder can be adjusted according to production needs to control the feeding amount of fluorite powder. The loss-in-weight scale accurately measures the weight of the conveyed fluorite powder, and by monitoring the changes in the weight of the material in real time, feedback controls the feeding speed of the star feeder to ensure that the feeding amount of fluorite powder is stable and accurate. The outlet of the loss-in-weight scale is connected to the external mixer, and the accurately measured fluorite powder is conveyed to the external mixer. It should be noted that, as an alternative implementation method, temperature and humidity sensors can also be installed on the fluorite silo to ensure the weight of the fluorite powder.

[0090] Specifically, a star feeder consists of a star-shaped feed valve and a feed screw. One end of the feed screw is connected to an external mixer, and the other end is connected to a fluorite silo. Fluorite powder is conveyed to the external mixer via the feed screw. The star-shaped feed valve has a good seal: Star-shaped feed valves are typically designed to prevent material leakage and, for ultrafine fluorite powder, to prevent material impaction.

[0091] like Figure 1As shown, an implementation method provided by this embodiment, the acid feeding mechanism includes a mixing acid tank, the outlet of the mixing acid tank is connected to the external mixer, and the inlet of the mixing acid tank is respectively connected to at least one acid solution. Mixing acid tank: a key equipment of the acid feeding mechanism, whose inlets are respectively connected to at least one acid solution, and sulfuric acid is used as the reaction acid. The function of the mixing acid tank is to mix 98 acid or 105 acid to achieve a suitable concentration and ratio to meet the requirements of the reaction. The outlet of the mixing acid tank is connected to the external mixer, and the mixed acid solution is transported to the external mixer through a pipeline to mix with fluorite powder. It should be noted that, as an alternative implementation method, a metering device, such as a metering pump, can also be provided to control the flow rate of the mixed acid.

[0092] like Figure 1 As shown, this is an implementation method provided by this embodiment, the outlet of the reactor is connected to a slag cooler, and the outlet of the slag cooler is connected to a gypsum silo. The slag cooler is used to receive the high-temperature material from the outlet of the reactor, and cools the material through a cooling medium to reduce the temperature of the material for subsequent storage and processing. The outlet of the slag cooler is connected to a gypsum silo, and the solid by-product (i.e., gypsum) after cooling enters the gypsum silo for storage. It should be noted that, as an alternative implementation method, a waste heat boiler can also be provided, and the waste heat boiler is provided at the high-temperature medium outlet of the slag cooler to improve energy utilization.

[0093] Specifically, such as Figure 3As shown, low-grade fluorite powder has a high impurity content. The reaction of sulfuric acid with low-grade fluorite powder is not sufficient. Therefore, an anti-slag spiral device 2 is provided in the reactor, and the anti-slag spiral device 2 is used to stir the fluorite powder and sulfuric acid to allow them to fully react. The anti-slag spiral device 2 is provided in the reactor, and the anti-slag spiral device 2 has a driving member, which is a motor. An anti-slag barrel is connected to the driving shaft of the driving member, and the axial end of the anti-slag barrel close to the driving member is open. The outer surface of the anti-slag barrel is provided with a first spiral stirring blade 4, and the inner surface of the anti-slag barrel is provided with a second spiral stirring blade 5. The spiral direction of the first spiral stirring blade 4 is opposite to the spiral direction of the second spiral stirring blade 5. A feed hopper 6 is provided at the end of the slag return tube away from the driving member. The feed hopper 6 is fan-shaped and extends radially outward from the slag return tube. The side of the feed hopper 6 facing the direction of rotation of the first spiral stirring blade 4 is open. When the slag return tube rotates, the reactor is filled with material, and the material moves from the reactor inlet to the reactor outlet under the action of the first spiral stirring blade 4. At the same time, when the slag return tube rotates, part of the material enters the interior of the slag return tube through the feed hopper 6, and moves toward the reactor inlet under the action of the second spiral stirring blade 5 until it re-enters the reactor through the opening of the slag return tube. By providing the slag return spiral device 2, the reaction between fluorite and sulfuric acid is ensured to be sufficient. The first 3.0m of the reactor head is made of alloy to reduce corrosion to the furnace body in the initial stage of the reaction, and a wall cleaning spiral is provided in the furnace head to prevent the problem of reaction crusting. The alloy refers to a nickel-based corrosion-resistant alloy.

[0094] Specifically, the wall cleaning spiral device is installed within the reactor and includes cleaning blades 3, which are arranged on the outer surface of the slag return tube and extend radially outward. Multiple cleaning blades 3 are arranged around the drive shaft along the circumference, with the ends of the cleaning blades 3 facing away from the drive shaft resting against the reactor wall. Multiple groups of cleaning blades 3 are arranged axially along the drive shaft. When the driving member rotates the cleaning blades 3, they remove residue from the reactor wall to prevent reaction crusting.

[0095] like Figure 4 As shown, an air duct is installed between the gaseous material outlet of the reactor and the inlet of the first purification tower. A slag pusher is installed in the air duct. The slag pusher includes a drive member and a spiral conveyor blade. The drive member is a motor. The spiral conveyor blade is driven by the drive member to rotate, continuously pushing the settled dust in the air duct back to the reactor, preventing ultrafine powder from clogging the air duct.

[0096] In addition, if Figure 1As shown, a hydrogen fluoride production method is also provided. Using the hydrogen fluoride production system described in the above scheme, the method includes the following steps: generating hydrogen fluoride gas by reacting fluorite powder and sulfuric acid in a reaction unit; removing dust, water, heavy components, and sulfur from the generated hydrogen fluoride gas in a purification unit; and further purifying the hydrogen fluoride gas in a distillation unit to obtain a high-purity hydrogen fluoride product. The reaction unit serves as the initial step, while the purification unit effectively removes impurities from the hydrogen fluoride gas, improving the purity of the product. The distillation unit further purifies the gas, ensuring the high quality of the final hydrogen fluoride product. By using the hydrogen fluoride production system, liquid hydrogen fluoride is used to cool the gaseous hydrogen fluoride, reducing the use of coolant. The liquid hydrogen fluoride can also be recycled, improving the system's production efficiency.

[0097] like Figure 1 As shown, an implementation method provided by this embodiment is that after the hydrogen fluoride gas is output from the purification unit, it is first cooled through the first working medium channel of the first cooler, and the temperature of the hydrogen fluoride gas is reduced from 30 degrees to 20 degrees. Subsequently, after cooling, the hydrogen fluoride gas is transported to the second cooler for further cooling, and the liquid hydrogen fluoride produced when the first working medium channel is cooled enters the cold crude acid tank. The liquid hydrogen fluoride in the cold crude acid tank enters the first cooling medium channel, and the gaseous hydrogen fluoride in the first working medium channel is cooled. After that, the liquid hydrogen fluoride in the first cooling medium channel enters the distillation tower and is purified by the distillation tower. The remaining hydrogen fluoride containing impurities after purification is sent back to the purification unit to participate in the processes of removing heavy components and removing water again. Another part of the hydrogen fluoride gas cooled by the first cooler is transported to the second cooler, and the hydrogen fluoride gas passing through the second cooler is further cooled to a liquid state. Then, liquid hydrogen fluoride is transported to the cold crude acid tank, and in the cold crude acid tank, liquid hydrogen fluoride is used to further cool the hydrogen fluoride gas in the first cooler. By arranging the cold crude acid tank, the hydrogen fluoride liquid in the cold crude acid tank serves as a cooling medium, which can effectively reduce the temperature of the hydrogen fluoride gas and make it easier to liquefy. At the same time, liquid hydrogen fluoride is utilized to cool the hydrogen fluoride gas in the first cooler, thereby achieving energy recycling and improving the energy efficiency of the entire production system. It should be noted that, as a replaceable embodiment, a crude distillation tower can also be provided, the inlet of the crude distillation tower being communicated with the second working medium channel of the second cooler, and the outlet of the rectifying tower being communicated with the rectifying tower. It should be noted that, as a replaceable embodiment, the hydrogen fluoride containing impurities of the rectifying tower can also be communicated with the inlet of the first cooling medium channel.

[0098] like Figure 1The figure shows an embodiment of this embodiment. The second cooler has a gaseous material outlet. Most of the gas discharged from the gaseous material outlet is impurity gas, including a small amount of hydrogen fluoride. After the hydrogen fluoride is absorbed by the sulfuric acid absorption device, the sulfuric acid is refluxed into the purification unit, allowing the hydrogen fluoride to recirculate and improve its utilization rate. It should be noted that as an alternative embodiment, an alkali scrubber can also be provided to absorb the sulfur dioxide.

[0099] like Figure 1 As shown, this is an implementation method provided by this embodiment. In the reaction unit, before the fluorite powder is transported to the reactor, it is first mixed with an acid solution in an external mixer, wherein the weight ratio of fluorite powder to sulfuric acid is 1:1.18. The weight of the acid is greater than the weight of the fluorite powder, which allows the fluorite powder and sulfuric acid to react excessively. The excess sulfuric acid acts as a catalyst during the reaction, accelerating the decomposition of the fluorite powder. It should be noted that as an alternative implementation method, the ratio of fluorite powder to mixed acid is not limited and can also be 1:1.25, or a weight ratio between 1:1.18 and 1:1.25.

[0100] like Figure 1 As shown, an implementation method provided by this embodiment is that before the fluorite powder is transported to the external mixer, the fluorite powder is first dried so that the water content of the fluorite powder is not more than 0.1%. Drying the fluorite powder effectively avoids the influence of moisture in the fluorite powder on subsequent reactions, thereby ensuring the stability and efficiency of the reaction. The dried fluorite powder is transported to the weighing platform through a spiral device, and after weighing, it is transported to the external mixer, where it is fully mixed with the pre-measured acid solution. The mixed material is transported to the reactor through a pipeline for high-temperature reaction. At the same time, precise weighing and ratio control ensure the accuracy of the ratio of fluorite powder and acid solution, further improving the production efficiency and product weight of hydrogen fluoride. It should be noted that, as an alternative implementation method, an acid concentration detection device can also be provided to detect the acid solution in the mixed acid tank.

[0101] like Figure 1As shown, this embodiment provides an implementation method. The purification unit includes a first purification tower and a second purification tower 1. In the first purification tower, sulfuric acid is sprayed to react with dust and water in the hydrogen fluoride gas to remove dust and moisture. In the second purification tower 1, weight removal and sulfur removal are performed. The first cooling medium channel of the first cooler passes through the low-temperature liquid hydrogen fluoride that returns to the liquid state. The liquid hydrogen fluoride vaporizes when heated, reducing the temperature of the purification tower to 30°. As the temperature decreases, the high-boiling point substance changes from gas to liquid and flows back to the first purification tower from the bottom of the tower. The impurities are removed by the first purification tower. The design of the first purification tower and the second purification tower 1 ensures the purity of the hydrogen fluoride gas during the production process and effectively avoids the impact of impurities such as dust, moisture and sulfur on subsequent processes and equipment. It should be noted that as an alternative implementation method, a dryer can also be provided to absorb the moisture in the hydrogen fluoride. It should be noted that as an alternative implementation method, the second purification tower can also be cooled by the liquid hydrogen fluoride returned from the distillation tower.

[0102] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications derived therefrom remain within the scope of protection of the present invention.

Claims

1. A hydrogen fluoride production system, characterized in that: The method comprises: a reaction unit, a purification unit and a distillation unit arranged in sequence, wherein the distillation unit comprises: distillation tower; a first cooler having a first cooling medium channel and a first working medium channel, wherein an inlet of the first working medium channel is connected to an outlet of the purification unit; a second cooler having a second cooling medium channel and a second working medium channel, wherein the inlet of the second working medium channel is connected to the outlet of the first working medium channel of the first cooler, the gaseous material outlet of the first working medium channel is connected to the inlet of the second working medium channel, and the outlet of the first cooling medium channel is connected to the distillation tower; The cold crude acid tank has a first inlet and a second inlet, the first inlet is connected to the liquid material outlet of the first working medium channel of the first cooler, the second inlet is connected to the liquid material outlet of the second cooling medium channel of the second cooler, and the outlet of the cold crude acid tank is connected to the inlet of the first cooling medium channel of the first cooler.

2. The hydrogen fluoride production system according to claim 1, characterized in that: An outlet of the first cooling medium channel of the first cooler is also in communication with the purification unit.

3. The hydrogen fluoride production system according to claim 1, characterized in that: The cold coarse acid tank comprises: a first cold coarse acid tank and a second cold coarse acid tank, and the first cold coarse acid tank and the second cold coarse acid tank are communicated.

4. The hydrogen fluoride production system according to claim 1, characterized in that: The distillation tower has a first outlet and a second outlet, the first outlet is connected to the purification unit, and the second outlet is connected to the inlet of the degassing tower; Alternatively, the first outlet is communicated with an inlet of a first cooling medium channel of the first cooler, and an outlet of the first cooling medium channel is communicated with the purification unit.

5. The hydrogen fluoride production system according to claim 4, characterized in that: The degassing tower has a first outlet and a second outlet, the first outlet is communicated with the inlet of the working medium channel of the second cooler, and the second outlet is communicated with the finished product tank.

6. The hydrogen fluoride production system according to claim 1, characterized in that: The second working medium channel of the second cooler has a gaseous material outlet, which is sequentially connected to a sulfuric acid absorption device, a three-stage water washing device, a negative pressure fan and a tail gas treatment unit. The sulfuric acid absorption device is also connected to the purification unit.

7. The hydrogen fluoride production system according to claim 1, characterized in that: The purification unit comprises: a first purification tower and a second purification tower (1), the first purification tower is connected to the pickling absorption device, and the outlet of the first purification tower is connected to the second purification tower (1) through a first pipeline.

8. The hydrogen fluoride production system according to any one of claims 1 to 7, characterized in that: The reaction unit includes an external mixer and a reaction furnace. The outlet of the external mixer is connected to the reaction furnace, and the inlet of the external mixer is connected to a fluorite powder feeding mechanism and an acid feeding mechanism respectively.

9. The hydrogen fluoride production system according to claim 8, characterized in that: The fluorite powder feeding mechanism includes a fluorite silo, an outlet of the fluorite silo is connected to a loss-in-weight scale via a star-shaped feeder, and an outlet of the loss-in-weight scale is connected to the external mixer.

10. The hydrogen fluoride production system according to claim 8, characterized in that: The acid feeding mechanism includes an acid mixing tank, the outlet of the acid mixing tank is connected to the external mixer, and the inlet of the acid mixing tank is respectively connected to at least one acid solution.

11. The hydrogen fluoride production system according to claim 8, characterized in that: The outlet of the reaction furnace is connected to a slag cooler, and the outlet of the slag cooler is connected to a gypsum silo.

12. A method for producing hydrogen fluoride, characterized in that: The hydrogen fluoride production system according to any one of claims 1 to 11 comprises the following steps: generating hydrogen fluoride gas through a reaction unit; The hydrogen fluoride gas is subjected to dust removal, water removal, heavy component removal and sulfur removal through a purification unit; The hydrogen fluoride gas is further purified by a distillation unit.

13. The method for producing hydrogen fluoride according to claim 12, wherein: After being output from the purification unit, the hydrogen fluoride gas is cooled through the first working medium channel of the first cooler. A small portion of the hydrogen fluoride in the first working medium channel is cooled into liquid hydrogen fluoride and enters the crude cold acid tank. The remaining portion of the gaseous hydrogen fluoride that has not been cooled enters the second cooler. The liquid hydrogen fluoride in the crude cold acid tank enters the first cooling medium channel and then enters the distillation tower. The remaining portion of the substance after being purified in the distillation tower is returned to the purification unit. After being cooled by the first cooler, part of the hydrogen fluoride gas is transported to the second cooler, and the hydrogen fluoride gas is further cooled into a liquid state by the second cooler, and then transported to the cold crude acid tank, and the liquid hydrogen fluoride in the cold crude acid tank is used to cool the hydrogen fluoride gas in the first cooler.

14. The method for producing hydrogen fluoride according to claim 13, wherein: The second cooler has a gaseous material outlet, through which the gaseous material is discharged, and then absorbed by the sulfuric acid absorption device and then refluxed into the purification unit.

15. The method for producing hydrogen fluoride according to claim 12, wherein: In the reaction unit, before the fluorite powder is transported to the reactor, it is first mixed with an acid solution in an external mixer, wherein the weight ratio of the powder to the acid is 1:1.18-1:1.

25.

16. The method for producing hydrogen fluoride according to claim 15, wherein: Before the fluorite powder is transported to the external mixer, the fluorite powder is first dried so that the moisture content of the fluorite powder is not greater than 0.1%. The dried fluorite powder is transported to a weighing platform through a spiral device, and then transported to the external mixer after being weighed.

17. The method for producing hydrogen fluoride according to any one of claims 12 to 16, characterized in that: The purification unit comprises a first purification tower and a second purification tower (1). In the first purification tower, sulfuric acid is sprayed to react with dust and water in the hydrogen fluoride gas to remove dust and water. In the second purification tower (1), liquid hydrogen fluoride returned from the first cooling medium channel of the first cooler cools the second purification tower (1), and impurities are cooled to liquid state. The liquid impurities flow back from the bottom of the second purification tower (1) into the first purification tower.

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