Fluorine-containing hydrogen chloride purification device

Abstract

The utility model provides a fluorine-containing hydrogen chloride purification device, and belongs to the technical field of hydrogen chloride purification. The fluorine-containing hydrogen chloride purification device comprises a calcium chloride dissolving tank, a stator-rotor reaction absorber, a circulating absorption tank, a settling tank, a plate-and-frame filter, a hydrogen fluoride absorption tower, an organic fluorine adsorption tower and an organic fluorine adsorption filler regenerator, the fluorine-containing hydrogen chloride purification device further comprises a dehydration assembly and a concentrated sulfuric acid drying tower, the stator-rotor reaction absorber comprises a fixed cylinder, a rotating part and a support, the rotating part and the fixed cylinder are coaxially, hermetically and rotatably connected, a first filter layer and a second filter layer which are penetrated by the rotating part are further arranged in the fixed cylinder, and the support is connected with the first filter layer and the second filter layer. The fixed cylinder is further provided with an air inlet, an air outlet and a liquid outlet, a rotating motor is fixedly arranged below the fixed cylinder, and the output end of the rotating motor is fixedly connected with the rotating part.

Description

Technical Field

[0001] The utility model belongs to the technical field of hydrogen chloride purification, and specifically relates to a fluorine-containing hydrogen chloride purification device. Background Art

[0002] A large amount of organic fluorine, hydrogen fluoride and other fluorine-containing gases are often produced during the production process of fluorine chemical industry. At present, the main treatment method for hydrogen chloride gas is usually water absorption method, which produces hydrochloric acid containing a certain amount of hydrogen fluoride and organic fluorine. Due to the presence of hydrogen fluoride and organic fluorine in hydrochloric acid, its application scope is narrowed and the selling price is reduced. Its subsequent application scope is restricted, which causes an imbalance between supply and demand over time. Excessive by-product hydrochloric acid (all contain a certain amount of fluoride or organic matter) cannot be absorbed by the market. Some manufacturers can only treat it as waste liquid, which seriously affects economic benefits. When it is sold as a product, the presence of fluorine in hydrochloric acid poses a potential hazard to the environment. Therefore, the effective removal of fluorine from hydrogen fluoride, organic fluorine-containing hydrogen chloride gas or fluorine-containing hydrochloric acid in fluorine chemical production is a problem that needs to be paid attention to and solved in the healthy development of fluorine chemical industry.

[0003] At present, the main treatment methods for hydrochloric acid or hydrogen chloride gas containing hydrogen fluoride are:

[0004] 1. Distillation is used to separate and recover the large amount of hydrogen fluoride contained in hydrogen chloride gas. This is a necessary means in industry. However, there will still be 100-2000 ppm of hydrogen fluoride in the hydrogen chloride after distillation, and it is impossible to completely separate hydrogen fluoride and hydrogen chloride.

[0005] 2. Dry defluorination is to use solid defluorinating agents to selectively absorb the impurity hydrogen fluoride in the by-product hydrogen chloride gas. The solid defluorinating agents reported in the literature include Al2O3, SiO2, CaCl2, CaO, CaCO3 and NaF. After the solid defluorinating agent fails, a large amount of solid waste will be generated, so this technology is only used for the removal of hydrogen fluoride with extremely low content.

[0006] 3. Wet defluorination: Wet defluorination uses solvents to selectively dissolve the impurity hydrogen fluoride in the by-product hydrogen chloride gas. The solvent used can be recycled after the impurities are resolved. The key to wet defluorination is the reaction of defluorinated substances with hydrofluoric acid, and the resulting product has a small partial pressure in high-content hydrochloric acid. The commonly used solution at present is to use hydrochloric acid containing boric acid to remove hydrogen fluoride from hydrogen chloride gas. A certain amount of boric acid is dissolved in 35% hydrochloric acid, and HF wet gas containing HCl is passed into the solution at a certain temperature and pressure. The boric acid in the hydrochloric acid absorbs HF and becomes fluoroboric acid. The absorbed solution can be recycled after silica gel adsorption and defluorination regeneration.

[0007] In addition, the patent published by Jiangxi University of Science and Technology (publication / announcement number: CN110817924A) reported the use of saturated CaCl2 solution to absorb hydrogen fluoride in hydrogen chloride gas. Saturated CaCl2 solution was added to the reactor, and fluorine-containing waste gas (fluorine content 45%) was passed into the bubbling reactor. The concentration of HCl tail gas after water washing and absorption was 37%. The defluorination rate of CaCl2 saturated solution was greater than 99%. After defluorination, the hydrogen chloride gas could reduce hydrogen fluoride to 0.001% at the lowest.

[0008] Hydrogen chloride gas contains a small amount of organic fluorine. For example, hydrogen chloride gas containing R22 and R23 produced in the process of producing refrigerants still contains a certain amount of R22, R23, R125, R115 and R134a after distillation. Currently, this hydrogen chloride gas is mainly absorbed into hydrochloric acid by water, and then decomposed into hydrogen chloride gas for subsequent use. However, after decomposition, its R22, R23, R125, R115 and R134a still contain 1000~2000ppm, which cannot be completely removed, causing serious impact on the subsequent use of HCl.

[0009] To this end, we propose a fluorine-containing hydrogen chloride purification device. Utility Model Content

[0010] In order to remove fluoride gas in hydrogen chloride gas, the utility model uses a stator-rotor reaction intensification device, combined with concentrated sulfuric acid dehydration and adsorption of trace hydrogen fluoride and organic fluorine and other combined technologies, to remove hydrogen fluoride in hydrogen chloride to below 1ppm and organic fluorine to below 10ppm, thereby meeting the requirements of subsequent industrial utilization.

[0011] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0012] A fluorine-containing hydrogen chloride purification device, comprising a calcium chloride dissolving tank, a stator-rotor reaction absorber, a circulating absorption tank, a settling tank, a plate-frame filter, a hydrogen fluoride absorption tower, an organic fluorine absorption tower and an organic fluorine absorption filler regenerator;

[0013] The fluorine-containing hydrogen chloride purification device also includes a dehydration component and a concentrated sulfuric acid drying tower. The dehydration component includes a primary condenser, a secondary condenser and a gas-liquid separator. The organic fluorine adsorption filler regenerator includes a heater, a cooler and a vacuum pump. The primary condenser outlet is connected to the secondary condenser inlet, the secondary condenser outlet is connected to the gas-liquid separator inlet, and the gas-liquid separator outlet is connected to the concentrated sulfuric acid drying tower.

[0014] The stator-rotor reaction absorber comprises a fixed cylinder, a rotating member and a bracket, wherein the rotating member and the fixed cylinder are coaxially sealed and rotatably connected, a first filter layer and a second filter layer passed through by the rotating member are arranged inside the fixed cylinder, an air inlet, an air outlet and a liquid outlet are arranged in the fixed cylinder, a rotating motor is fixedly arranged below the fixed cylinder, and an output end of the rotating motor is fixedly connected to the rotating member;

[0015] Among them, the rotating part includes a positioning shaft, a connecting shaft and a power shaft which are arranged in sequence from top to bottom and fixedly connected to each other. A liquid inlet cavity is arranged in the power shaft, and the liquid inlet cavity has two openings facing outward. One opening leads to the outside of the fixed cylinder body and is connected to the liquid inlet pipe, and the other opening leads to the inside of the fixed cylinder body and a nozzle is fixedly arranged at the opening.

[0016] Preferably, the first filter layer and the second filter layer are arranged from top to bottom, the first filter layer is provided with a plurality of conical openings, the upper opening radius of the conical opening is smaller than the lower opening radius, and the second filter layer is provided with a plurality of liquid drop openings, the liquid drop opening radius is larger than the upper opening radius of the conical opening.

[0017] Preferably, the air inlet is opened on the side wall of the fixed cylinder and is located between the first filter layer and the second filter layer, and the fixed cylinder is fixedly and sealedly connected with an air inlet pipe at the air inlet.

[0018] Preferably, the air outlet is located at the top of the fixed cylinder, and the fixed cylinder is fixedly and sealedly connected with an air outlet pipe at the air outlet.

[0019] Preferably, the fixed cylinder includes an upper cylinder and a lower cylinder, the dividing point between the upper cylinder and the lower cylinder is the upper surface of the first filter layer, a sealing ring for connecting the upper cylinder and the lower cylinder is arranged between the upper cylinder and the lower cylinder, a liquid infusion port is also opened on the side wall of the upper cylinder, and the fixed cylinder is fixedly and sealedly connected with a liquid infusion tube at the liquid infusion port.

[0020] Preferably, the liquid outlet is located at the bottom end of the fixed cylinder, and the fixed cylinder is fixedly and sealedly connected with a liquid outlet pipe at the liquid outlet.

[0021] Preferably, the outlet of the calcium chloride dissolving tank is connected to the stator-rotor reaction absorber through a liquid inlet pipe, and the stator-rotor reaction absorber is connected to the circulating absorption tank through a liquid outlet pipe at the liquid outlet; the liquid outlet of the circulating absorption tank is connected to the inlet of the sedimentation tank, and the liquid outlet of the plate and frame filter returns to the calcium chloride dissolving tank.

[0022] Preferably, the gas outlet of the stator-rotor reaction absorber is the hydrogen chloride gas after the hydrogen fluoride is removed, the gas outlet is connected to the inlet of the dehydration component, and the outlet of the dehydration component is connected to the gas phase outlet of the hydrogen fluoride absorption tower.

[0023] A method for purifying fluorine-containing hydrogen chloride in a fluorine-containing hydrogen chloride purification device comprises the following steps:

[0024] ① Dissolved air intake:

[0025] Dissolving calcium chloride solid in a calcium chloride dissolving tank, and then feeding it into a stator-rotor reaction absorber through a liquid inlet pipe, and feeding hydrogen chloride gas into the stator-rotor reaction absorber through an air inlet pipe and an air inlet;

[0026] ②Removal of hydrogen fluoride:

[0027] The stator-rotor reactor is started, and the calcium chloride solution and the hydrogen chloride gas of the stator-rotor reaction absorber are fully reacted in the stator-rotor reaction absorber; hydrogen fluoride and calcium chloride react to generate calcium fluoride, forming calcium fluoride particles, which flow out from the liquid outlet and the liquid outlet pipe along with the calcium chloride solution and enter the circulating absorption tank, and the calcium fluoride slurry in the calcium chloride solution entering the circulating absorption tank is discharged into the settling tank for settling, and the calcium chloride solution in the circulating absorption tank that does not contain the calcium fluoride slurry is again passed to the liquid inlet pipe and flows to the stator-rotor reaction absorber; the settled calcium fluoride concentrated phase is sent to the plate-frame filter press for filtration through a filter pump, and the calcium fluoride filter cake is recycled and reused, and the filtrate is refluxed to the settling tank;

[0028] ③Dehydration and drying:

[0029] The hydrogen chloride gas from which hydrogen fluoride has been removed is discharged from the gas outlet of the stator-rotor reaction absorber and enters the dehydration component for dehydration and drying treatment. The hydrogen chloride gas is cooled by cooling water and chilled water, and then passed into the concentrated sulfuric acid drying tower for deep drying.

[0030] The hydrogen chloride gas enters the stator-rotor reaction absorber through the gas phase inlet of the stator-rotor reaction absorber and the concentrated sulfuric acid from the liquid phase inlet of the stator-rotor reaction absorber. Under the action of the stator-rotor enhanced mass transfer, the water in the hydrogen chloride fully enters the concentrated sulfuric acid solution, and the gas outlet of the stator-rotor reaction absorber enters the concentrated sulfuric acid drying tower again, and contacts and dries with the concentrated sulfuric acid from the top of the tower again; the concentrated sulfuric acid enters in a countercurrent manner, the fresh concentrated sulfuric acid enters the concentrated sulfuric acid drying tower, and then the concentrated sulfuric acid at the bottom of the tower enters the stator-rotor reactor again;

[0031] ④Remove hydrogen fluoride residue:

[0032] The hydrogen chloride gas after the hydrogen fluoride is removed by adsorption enters the organic fluorine adsorption tower to remove the organic fluorine. The adsorption material selectively physically adsorbs the organic fluorine or gaseous organic matter in the hydrogen chloride and removes it. After the adsorption is saturated, the filler is regenerated by micro-thermal regeneration or vacuum regeneration.

[0033] Compared with the prior art, the utility model has the following beneficial effects:

[0034] The utility model utilizes a stator-rotor reaction absorber to first remove hydrogen fluoride from hydrogen chloride. The stator-rotor reaction absorber is suitable for various multiphase system process intensification. Taking the gas-liquid reaction system as an example, the liquid is sprayed on the second filter layer through a nozzle, dispersed by the high-speed rotating nozzle, and forms tiny droplets, which improves its surface renewal rate. When these droplets fall on the second filter layer, the liquid is redistributed, and the contact area between the gas phase and the liquid phase increases. In this process, the gas phase and the liquid phase enter the stator-rotor reaction absorber through the outer edge inlet, and have a large surface contact opportunity with the liquid in the continuous movement, and the mass transfer effect is improved.

[0035] The stator-rotor reaction absorber used in the utility model has the effect of strengthening the reaction mass transfer. Compared with the common reaction kettle or the packed tower, the mass transfer rate is increased to more than 10 to 1000 times.

[0036] The stator-rotor reactive absorber has the following features:

[0037] 1) In the stator-rotor flow process, the liquid is dispersed and refined during high-speed rotation and redistributed on the second filter layer. Under the action of the second filter layer and the first filter layer, the internal pressure of the gas phase rises, and the gas phase and the liquid phase have multiple contact opportunities between the second filter layer and the first filter layer, which improves the reaction efficiency;

[0038] 2) There is no filler in the stator-rotor reaction absorber, which avoids the material blockage phenomenon in the calcium fluoride precipitation crystallization reaction formed during the reaction process, and the internal turbulence is high, which has a certain self-cleaning effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the implementation methods of the present application, the following is a brief introduction to the drawings required for use in the implementation methods. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0040] Figure 1 It is an overall structural diagram provided by the implementation method of this application;

[0041] Figure 2 This is a cross-sectional diagram provided by the embodiment of the present application. Figure 1 ;

[0042] Figure 3 This is a cross-sectional diagram provided by the embodiment of the present application. Figure 2 ;

[0043] Figure 4 It is a comparison diagram of the tapered port and the liquid drop port provided in the embodiment of the present application;

[0044] Figure 5 A process flow chart is provided for an embodiment of the present application.

[0045] In the figure, 1, calcium chloride dissolving tank; 2, stator-rotor reaction absorber; 3, circulating absorption tank; 4, sedimentation tank; 5, plate-and-frame filter; 6, hydrogen fluoride absorption tower; 7, organic fluorine absorption tower; 8, organic fluorine absorption filler regenerator; 9, dehydration assembly; 10, concentrated sulfuric acid drying tower;

[0046] 81. Heater; 82. Cooler; 83. Vacuum pump;

[0047] 91. Primary condenser; 92. Secondary condenser; 93. Gas-liquid separator;

[0048] 21. Fixed cylinder; 211. Upper cylinder; 212. Lower cylinder; 213. Sealing ring; 214. Liquid filling port; 215. Liquid filling pipe; 22. Rotating member; 221. Positioning shaft; 222. Connecting shaft; 223. Power shaft; 224. Nozzle; 23. Bracket; 24. First filter layer; 204. Conical port; 25. Second filter layer; 205. Liquid drop port; 26. Air inlet; 206. Air inlet pipe; 27. Air outlet; 207. Air outlet pipe; 28. Liquid outlet; 208. Liquid outlet pipe; 29. ​​Rotating motor. DETAILED DESCRIPTION

[0049] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

[0050] Reference Figure 1 and 5 A fluorine-containing hydrogen chloride purification device includes a calcium chloride dissolving tank 1, a stator-rotor reaction absorber 2, a circulating absorption tank 3, a sedimentation tank 4, a plate and frame filter 5, a hydrogen fluoride absorption tower 6, an organic fluorine adsorption tower 7 and an organic fluorine adsorption filler regenerator 8.

[0051] The fluorine-containing hydrogen chloride purification device also includes a dehydration component 9 and a concentrated sulfuric acid drying tower 10. The dehydration component 9 includes a primary condenser 91, a secondary condenser 92 and a gas-liquid separator 93. The organic fluorine adsorption filler regenerator 8 includes a heater 81, a cooler 82, and a vacuum pump 83. The outlet of the primary condenser 91 is connected to the inlet of the secondary condenser 92, the outlet of the secondary condenser 92 is connected to the inlet of the gas-liquid separator 93, and the outlet of the gas-liquid separator 93 is connected to the concentrated sulfuric acid drying tower 10.

[0052] Among them, multiple groups of pipelines, valves and pumps are arranged between the calcium chloride dissolving tank 1, the stator-rotor reaction absorber 2, the circulating absorption tank 3, the sedimentation tank 4, the plate and frame filter 5, the hydrogen fluoride absorption tower 6, the organic fluorine adsorption tower 7 and the organic fluorine adsorption filler regenerator 8.

[0053] The solid outlet of the plate and frame filter 5 is a crude calcium fluoride product, which is further washed, filtered, dried and other processes to obtain a pure calcium fluoride product for sale or use. The device purifies hydrogen chloride or hydrochloric acid in a system containing hydrogen fluoride or organic fluorine and other impurities in hydrogen chloride gas or hydrochloric acid. If there is only hydrogen fluoride gas in the hydrogen chloride gas, the device does not need an organic fluorine adsorption filler regenerator 8.

[0054] The stator-rotor reaction absorber 2 plays a role in strengthening the reaction, and the concentrated sulfuric acid drying tower 10 is composed of a multi-stage countercurrent absorption tower, or the same structure as the stator-rotor reaction absorber 2 is used alone.

[0055] The filler of the organic fluorine adsorption filler regenerator 8 mainly uses oxides, chlorides, hydroxides or carbonates of calcium, magnesium and aluminum as adsorbents. The organic fluorine adsorption filler is a material that selectively adsorbs organic fluorine. Its adsorption form is mainly physical adsorption, and it can be recycled through regeneration. Its regeneration method is micro-thermal regeneration or athermal vacuum regeneration. For example, if micro-thermal regeneration is used, the regeneration gas (inert gas) needs to be heated and heated before regeneration, while the athermal regeneration uses a vacuum pump 83 to suck out the organic fluorine gas in the organic fluorine adsorption tower 7.

[0056] Reference Figure 1-3 The stator-rotor reaction absorber 2 includes a fixed cylinder body 21, a rotating member 22 and a bracket 23. The rotating member 22 and the fixed cylinder body 21 are coaxially sealed and rotatably connected. A first filter layer 24 and a second filter layer 25 passed by the rotating member 22 are also arranged inside the fixed cylinder body 21. The fixed cylinder body 21 is also provided with an air inlet 26, an air outlet 27 and a liquid outlet 28. A rotating motor 29 is fixedly arranged below the fixed cylinder body 21, and the output end of the rotating motor 29 is fixedly connected to the rotating member 22.

[0057] Among them, the rotating member 22 includes a positioning shaft 221, a connecting shaft 222 and a power shaft 223 which are arranged in sequence from top to bottom and fixedly connected to each other. A liquid inlet cavity is arranged in the power shaft 223, and the liquid inlet cavity has two openings facing outward. One opening leads to the outside of the fixed cylinder body 21 and is connected to the liquid inlet pipe, and the other opening leads to the inside of the fixed cylinder body 21 and a nozzle 224 is fixedly arranged at the opening.

[0058] Reference Figure 2-4 The first filter layer 24 and the second filter layer 25 are arranged from top to bottom. A plurality of conical openings 204 are opened in the first filter layer 24. The radius of the upper opening of the conical opening 204 is smaller than the radius of the lower opening. The second filter layer 25 is opened with a plurality of liquid drop openings 205. The radius of the liquid drop opening 205 is larger than the radius of the upper opening of the conical opening 204.

[0059] The air inlet 26 is provided on the side wall of the fixed cylinder 21 and is located between the first filter layer 24 and the second filter layer 25 , and the fixed cylinder 21 is fixedly and sealedly connected with an air inlet pipe 206 at the air inlet 26 .

[0060] The air outlet 27 is located at the top of the fixed cylinder 21 , and the fixed cylinder 21 is fixedly and sealedly connected with an air outlet pipe 207 at the air outlet 27 .

[0061] The fixed cylinder 21 includes an upper cylinder 211 and a lower cylinder 212. The dividing point between the upper cylinder 211 and the lower cylinder 212 is the upper surface of the first filter layer 24. A sealing ring 213 for connecting the upper cylinder 211 and the lower cylinder 212 is arranged between the upper cylinder 211 and the lower cylinder 212. A liquid replenishment port 214 is also opened on the side wall of the upper cylinder 211, and a liquid replenishment pipe 215 is fixedly and sealedly connected to the liquid replenishment port 214 of the fixed cylinder 21. Before passing the gas phase, a small amount of liquid phase needs to be added to the space formed by the upper cylinder 211 and the first filter layer 24 through the liquid replenishment port 214 for further absorption of gas phase impurities. The sealing ring 213 is used for easy replacement and cleaning.

[0062] The liquid outlet 28 is located at the bottom end of the fixed cylinder 21 , and the fixed cylinder 21 is fixedly and sealedly connected with a liquid outlet pipe 208 at the liquid outlet 28 .

[0063] The outlet of the calcium chloride dissolving tank 1 is connected to the stator-rotor reaction absorber 2 through a liquid inlet pipe, and the stator-rotor reaction absorber 2 is connected to the circulating absorption tank 3 through a liquid outlet pipe 208 at the liquid outlet 28; the liquid outlet of the circulating absorption tank 3 is connected to the inlet of the sedimentation tank 4, and the liquid outlet of the plate and frame filter 5 returns to the calcium chloride dissolving tank 1.

[0064] The gas outlet 27 of the stator-rotor reaction absorber 2 is for flowing out the hydrogen chloride gas after the hydrogen fluoride is removed. The gas outlet 27 is connected to the inlet of the dehydration component 9, and the outlet of the dehydration component 9 is connected to the gas phase outlet of the hydrogen fluoride absorption tower 6.

[0065] When the gas is introduced, the liquid phase is introduced first, and the liquid phase enters from the liquid inlet cavity and is sprayed out from the nozzle 224. Under the action of the rotating motor 29, the output end of the rotating motor 29 drives the nozzle 224 and the liquid phase to rotate, and the liquid phase is sprayed upward while rotating. Under the action of inertia, the liquid phase is evenly sprayed onto the second filter layer 25. The liquid phase falling on the second filter layer 25 has a reduced flow rate, and the liquid phase in the air is the first contact object of the gas phase. The gas phase will first contact with the liquid phase sprayed in the air as the first contact; when the liquid phase is evenly sprayed onto the second filter layer 25, because the radius of the liquid outlet 205 is very small, the liquid phase will not immediately flow to the bottom of the second filter layer 25, but will contact with the gas on the surface of the liquid phase interface; due to incomplete contact, part of the gas has not contacted the liquid phase, and the gas (HCl is discharged upward) Floating upward, there is also a liquid phase in the upper layer of the second filter layer 25, which will further absorb the gas phase, and because a plurality of tapered openings 204 are provided in the first filter layer 24, the upper opening radius of the tapered opening 204 is smaller than the lower opening radius, and a plurality of liquid drop openings 205 are provided in the second filter layer 25, and the radius of the liquid drop opening 205 is larger than the upper opening radius of the tapered opening 204, the liquid phase on the second filter layer 25 will not drip quickly, but drip slowly under the action of surface tension, and at this time there is also resistance to the gas phase moving upward, which will further slow down the upward speed of the gas phase. In the process of the gas phase passing through the tapered opening 204 in the second filter layer 25 and flowing to the air outlet 27, not only the absorption time is increased, but the gas phase completely passes through the liquid phase above the second filter layer 25, and the contact area is also increased, and each gas phase passing through the tapered opening 204 can be absorbed, thereby improving the absorption efficiency.

[0066] The gas enters from the air inlet 26 and is located between the first filter layer 24 and the second filter layer 25.

[0067] Reference Figure 5 , a method for purifying fluorine-containing hydrogen chloride in a fluorine-containing hydrogen chloride purification device, comprising the following steps:

[0068] ① Dissolved air intake:

[0069] Calcium chloride solid is dissolved in the calcium chloride dissolving tank 1 , and after being dissolved, it is sent to the stator-rotor reaction absorber 2 through the liquid inlet pipe, and hydrogen chloride gas is sent to the stator-rotor reaction absorber 2 through the air inlet pipe 206 and the air inlet 26 .

[0070] ②Removal of hydrogen fluoride:

[0071] The stator-rotor reactor is started, and the calcium chloride solution and the hydrogen chloride gas of the stator-rotor reaction absorber 2 fully react in the stator-rotor reaction absorber 2; hydrogen fluoride and calcium chloride react to generate calcium fluoride, forming calcium fluoride particles. Since the solubility of calcium fluoride is extremely small, the calcium fluoride particles are finally formed and discharged into the circulation absorption tank 3 along with the solution, that is, the calcium fluoride particles flow out from the liquid outlet 28 and the liquid outlet pipe 208 along with the calcium chloride solution and enter the circulation absorption tank 3. The calcium fluoride slurry in the calcium chloride solution entering the circulation absorption tank 3 is discharged into the settling tank 4 for settling, and the calcium chloride solution in the circulation absorption tank 3 that does not contain the calcium fluoride slurry is again connected to the liquid inlet pipe and flows to the stator-rotor reaction absorber 2; the calcium fluoride concentrated phase after settling is sent to the plate-frame filter press 5 for filtration through a filter pump, the calcium fluoride filter cake is recycled, and the filtrate is refluxed to the settling tank 4;

[0072] ③Dehydration and drying:

[0073] The hydrogen chloride gas from which hydrogen fluoride has been removed is discharged from the gas outlet 27 of the stator-rotor reaction absorber 2 and enters the dehydration assembly 9 for dehydration and drying treatment. The hydrogen chloride gas is cooled by cooling water and refrigerated water and then passed into the concentrated sulfuric acid drying tower 10 for deep drying.

[0074] The hydrogen chloride gas enters the stator-rotor reaction absorber 2 through the gas phase inlet of the stator-rotor reaction absorber 2 and the concentrated sulfuric acid from the liquid phase inlet of the stator-rotor reaction absorber 2. Under the action of the stator-rotor enhanced mass transfer, the moisture in the hydrogen chloride fully enters the concentrated sulfuric acid solution. The gas outlet 27 of the stator-rotor reaction absorber 2 enters the concentrated sulfuric acid drying tower 10 again, and contacts and dries with the concentrated sulfuric acid from the top of the tower again, and the moisture in the hydrogen chloride is removed to below 10 ppm; the concentrated sulfuric acid enters in a countercurrent manner, and the fresh concentrated sulfuric acid enters the concentrated sulfuric acid drying tower 10, and then the concentrated sulfuric acid at the bottom of the tower enters the stator-rotor reactor again;

[0075] ④Remove hydrogen fluoride residue:

[0076] The hydrogen chloride gas after the hydrogen fluoride is removed by adsorption enters the organic fluorine adsorption tower 7 to remove the organic fluorine. The adsorption material selectively physically adsorbs the organic fluorine or gaseous organic matter in the hydrogen chloride and removes it. After the adsorption is saturated, the filler is regenerated by micro-thermal regeneration or vacuum regeneration.

[0077] Two organic fluorine adsorption towers 7 are provided, which are used for switching between adsorption and regeneration respectively.

[0078] The utility model uses a stator-rotor reaction absorber 2 to remove hydrogen fluoride, and while strengthening the reaction effect, effectively avoids the problem of reaction equipment blockage caused by calcium fluoride crystals in the system. At the same time, calcium chloride solid is dissolved to prepare a solution as liquid feed for the stator-rotor reaction absorber 2, and the liquid filtered after the reaction is used as liquid circulation. No excess water is introduced into the device, and the loss caused by the dissolution of hydrogen chloride gas in water is effectively avoided.

[0079] The utility model further dehydrates by using a solid adsorbent to further adsorb and remove hydrogen fluoride, wherein the water content in the hydrogen chloride gas is less than 10 ppm, and then the solid adsorbent is used to adsorb a trace amount of hydrogen fluoride, which greatly reduces the amount of solid adsorbent used compared to ordinary direct solid adsorption.

[0080] For the adsorption of organic fluorine, special adsorbents are screened, especially for small molecules of R22 and R23, and highly selective adsorbents are used. The HF-R23 adsorbent produced by Sinopec Catalyst Co., Ltd. is used to reduce the organic fluorine to below 10ppm after adsorption.

[0081] All technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

Claims

1. A fluorine-containing hydrogen chloride purification device, characterized in that: It comprises a calcium chloride dissolving tank (1), a stator-rotor reaction absorber (2), a circulating absorption tank (3), a settling tank (4), a plate-and-frame filter (5), a hydrogen fluoride absorption tower (6), an organic fluorine absorption tower (7) and an organic fluorine absorption filler regenerator (8); The fluorine-containing hydrogen chloride purification device further comprises a dehydration component (9) and a concentrated sulfuric acid drying tower (10); the dehydration component (9) comprises a primary condenser (91), a secondary condenser (92) and a gas-liquid separator (93); the organic fluorine adsorption filler regenerator (8) comprises a heater (81), a cooler (82) and a vacuum pump (83); the outlet of the primary condenser (91) is connected to the inlet of the secondary condenser (92), the outlet of the secondary condenser (92) is connected to the inlet of the gas-liquid separator (93), and the outlet of the gas-liquid separator (93) is connected to the concentrated sulfuric acid drying tower (10); The stator-rotor reaction absorber (2) comprises a fixed cylinder (21), a rotating member (22) and a bracket (23); the rotating member (22) and the fixed cylinder (21) are coaxially sealed and rotatably connected; a first filter layer (24) and a second filter layer (25) passed through by the rotating member (22) are also arranged inside the fixed cylinder (21); an air inlet (26), an air outlet (27) and a liquid outlet (28) are also provided in the fixed cylinder (21); a rotating motor (29) is fixedly arranged below the fixed cylinder (21); and an output end of the rotating motor (29) is fixedly connected to the rotating member (22); The rotating member (22) comprises a positioning rotating shaft (221), a connecting rotating shaft (222) and a power rotating shaft (223) which are arranged in sequence from top to bottom and fixedly connected to each other. A liquid inlet cavity is arranged in the power rotating shaft (223). The liquid inlet cavity has two openings facing outwards, one opening leads to the outside of the fixed cylinder (21) and is connected to the liquid inlet pipe, and the other opening leads to the inside of the fixed cylinder (21) and a nozzle (224) is fixedly arranged at the opening.

2. The fluorine-containing hydrogen chloride purification device according to claim 1, characterized in that: The first filter layer (24) and the second filter layer (25) are arranged from top to bottom. The first filter layer (24) is provided with a plurality of conical openings (204), the radius of the upper opening of the conical opening (204) being smaller than the radius of the lower opening. The second filter layer (25) is provided with a plurality of liquid drop openings (205), the radius of the liquid drop openings (205) being larger than the radius of the upper opening of the conical opening (204).

3. The fluorine-containing hydrogen chloride purification device according to claim 1, characterized in that: The air inlet (26) is provided on the side wall of the fixed cylinder (21) and is located between the first filter layer (24) and the second filter layer (25), and the fixed cylinder (21) is fixedly and sealedly connected to an air inlet pipe (206) at the air inlet (26).

4. The fluorine-containing hydrogen chloride purification device according to claim 1, characterized in that: The air outlet (27) is located at the top end of the fixed cylinder (21), and the fixed cylinder (21) is fixedly and sealedly connected to an air outlet pipe (207) at the air outlet (27).

5. The fluorine-containing hydrogen chloride purification device according to claim 3, characterized in that: The fixed cylinder (21) comprises an upper cylinder (211) and a lower cylinder (212); the dividing portion between the upper cylinder (211) and the lower cylinder (212) is the upper surface of the first filter layer (24); a sealing ring (213) for connecting the upper cylinder (211) and the lower cylinder (212) is provided between the upper cylinder (211) and the lower cylinder (212); a liquid replenishing port (214) is also provided on the side wall of the upper cylinder (211); and a liquid replenishing tube (215) is fixedly and sealedly connected to the liquid replenishing port (214) of the fixed cylinder (21).

6. The fluorine-containing hydrogen chloride purification device according to claim 3, characterized in that: The liquid outlet (28) is located at the bottom end of the fixed cylinder (21), and the fixed cylinder (21) is fixedly and sealedly connected with a liquid outlet pipe (208) at the liquid outlet (28).

7. The fluorine-containing hydrogen chloride purification device according to claim 3, characterized in that: The outlet of the calcium chloride dissolving tank (1) is connected to the stator-rotor reaction absorber (2) via a liquid inlet pipeline, and the stator-rotor reaction absorber (2) is connected to the circulating absorption tank (3) at the liquid outlet (28) via a liquid outlet pipe (208); the liquid outlet of the circulating absorption tank (3) is connected to the inlet of the sedimentation tank (4), and the liquid outlet of the plate-frame filter (5) returns to the calcium chloride dissolving tank (1).

8. The fluorine-containing hydrogen chloride purification device according to claim 3, characterized in that: The gas outlet (27) of the stator-rotor reaction absorber (2) is for flowing out the hydrogen chloride gas after the hydrogen fluoride is removed. The gas outlet (27) is connected to the inlet of the dehydration component (9), and the outlet of the dehydration component (9) is connected to the gas phase outlet of the hydrogen fluoride absorption tower (6).

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