Evaporative condensing apparatus for electronic grade hydrochloric acid

Abstract

The present application relates to a kind of electronic grade hydrochloric acid evaporation condensing equipment, comprising: tank, tank is provided with liquid inlet, vapor phase outlet, the bottom of tank is provided with heating pipe;Pressure regulating device, be set in tank, for producing pressure at the bottom of tank;Condenser, including vapor phase inlet, liquid phase outlet, vapor phase inlet is connected to vapor phase outlet;Demister, connect to liquid phase outlet, demister is provided with demisting efficiency adjusting device, and demisting efficiency adjusting device is used to adjust the interception efficiency of demister.This application can adjust the steam rising rate of the bottom of tank and the demisting efficiency of demister by combining pressure regulating device and demisting efficiency adjusting device, so that after the combination, the proportion of water and impurities in steam can be reduced while reducing the demisting efficiency of demister according to the change of mother liquor concentration after evaporation purification of hydrochloric acid mother liquor condensing process, to prevent demister from being blocked by liquid convergence.

Description

Technical Field

[0001] This invention relates to the field of electronic-grade hydrochloric acid condensation, specifically to an evaporation and condensation device for electronic-grade hydrochloric acid. Background Technology

[0002] Hydrochloric acid is an aqueous solution of hydrogen chloride (HCl) and is a common chemical. Depending on its application, hydrochloric acid can be classified into industrial grade, electronic grade, and reagent grade. Electronic grade hydrochloric acid refers to products that can be used in pharmaceuticals, chemicals, semiconductors, and large-scale integrated circuits.

[0003] The purification of electronic-grade hydrochloric acid generally employs a distillation column, followed by condensation of the vapor produced in the column. After condensation, most of the vapor returns to a liquid state, leaving a small amount of vapor remaining. During the distillation process, the initial HCl concentration of the hydrochloric acid mother liquor is high, resulting in a low azeotropic point, and HCl volatilizes more readily than water. As distillation progresses, the HCl concentration gradually decreases, while the concentration of impurities gradually increases. At this point, water begins to volatilize more readily than HCl, and a small amount of impurities also volatilize. In the latter half of the distillation process, the azeotropic point of the hydrochloric acid mother liquor rises, increasing the proportion of water in the vapor. This also raises the temperature of the water vapor. Current technology does not address these changes in the distillation process, resulting in a significant amount of residual vapor remaining after condensation, even after the water temperature and proportion in the vapor have increased. This residual vapor tends to accumulate in the demister, reducing its ability to intercept droplets and drastically increasing airflow resistance.

[0004] The purpose of this invention is to design an evaporation and condensation device for electronic-grade hydrochloric acid to address the problems existing in the prior art. Summary of the Invention

[0005] In view of the problems existing in the prior art, the present invention provides an evaporation and condensation device for electronic grade hydrochloric acid, which can effectively solve at least one of the problems existing in the prior art.

[0006] The technical solution of this invention is:

[0007] An evaporation and condensation device for electronic-grade hydrochloric acid, comprising:

[0008] An evaporator includes a tank body, which is provided with a liquid inlet and a vapor phase outlet, and a heating tube is provided at the bottom of the tank body;

[0009] A pressure regulating device, located inside the tank, is used to generate pressure at the bottom of the tank.

[0010] The condenser includes a vapor phase inlet and a liquid phase outlet, with the vapor phase inlet connected to the vapor phase outlet;

[0011] The demister is connected to the liquid phase outlet. The demister is equipped with a demister efficiency adjustment device, which is used to adjust the interception efficiency of the demister.

[0012] Furthermore, the demister includes an airflow duct made of an elastic material, and the airflow duct is filled with demister mesh;

[0013] The defogging efficiency adjustment device includes a spring and a foam sleeve. The foam sleeve is integrally formed with the spring in a stretched state. When the spring is not under force, it causes the foam sleeve to contract together. The foam sleeve is fitted around the airflow duct. One end of the foam sleeve is fixedly connected to the airflow duct, and the other end of the foam sleeve is stretched or relaxed by a telescopic drive. After the foam sleeve contracts, it creates wrinkles and contracts the airflow duct, reducing the gap of the defogging mesh.

[0014] Furthermore, a layer of rubber tubing is attached to the inner wall of the foam sleeve.

[0015] Furthermore, the rubber hose is provided with several working holes at intervals along its axial direction, the foam sleeve is provided with an inner groove at the position corresponding to the working holes, and the airflow duct is provided with several swing plates at intervals along its axial direction. The top of the swing plate is fixedly connected to a working protrusion, which protrudes from the outer surface of the airflow duct. During the process of stretching or relaxing the other end of the foam sleeve through the telescopic drive, the working holes and inner grooves pass through the working protrusion in sequence, driving the working protrusion to drive the swing plate to swing, thereby agitating the demisting wire mesh.

[0016] Furthermore, an elastic element connects the swing plate and the airflow duct, which allows the swing plate to adhere to the inner wall of the airflow duct without being subjected to force.

[0017] Furthermore, the pressure regulating device includes:

[0018] A partition plate is installed inside the tank above the heating pipe. The partition plate has several packing storage slots arranged longitudinally. Each packing storage slot has a movable plate that moves up and down. The movable plate has multiple through holes for steam to pass through. The packing storage slots are filled with packing particles. The packing particles are used to generate pressure on the bottom of the tank. The number of packing particles is positively correlated with the pressure generated on the bottom of the tank by the packing particles.

[0019] The buffer box includes a fixed box and a movable box, which are connected. The fixed box surrounds the top of the packing storage groove, and the movable box is hinged to one side of the packing storage groove. The end of the movable box away from the packing storage groove is inclined downward.

[0020] The lifting drive is located at the bottom of the tank. The telescopic end of the lifting drive is connected to the movable plate. The movable plate is equipped with a connecting rod that drives the movable box to move. When the lifting drive extends, it drives the movable plate and the connecting rod to move upward, thereby gradually pushing the filler particles into the movable box. When the lifting drive retracts, it drives the movable plate and the connecting rod to move downward, thereby gradually pushing the filler particles into the filler storage tank.

[0021] Furthermore, the filler particles have a spherical structure and multiple through-holes.

[0022] Furthermore, the end of the movable box overlaps with the end of the fixed box. The bottom of the movable box, located outside the fixed box, is hinged to one side of the fixed box. The filling storage groove protrudes from the partition plate. In the unstressed state, the end of the movable box away from the fixed box tilts downward and abuts against the partition plate. The connecting rod moves upward and then disengages from the movable box. After the connecting rod moves downward, it presses down on the movable box, causing the movable box to flip up.

[0023] Furthermore, a shielding component connects the movable box and the fixed box.

[0024] Furthermore, during the distillation process, the lifting drive first rises to the highest point to reduce the number of packing particles in the packing storage tank, and then the lifting drive is gradually lowered to increase the number of packing particles in the packing storage tank.

[0025] Therefore, the present invention provides the following effects and / or advantages:

[0026] This application combines a pressure regulating device and a demisting efficiency regulating device to adjust the steam rise rate at the bottom of the tank and the demisting efficiency of the demister. Thus, the combination of the two devices can reduce the proportion of water and impurities in the steam and reduce the demisting efficiency of the demister based on the change in the concentration of the mother liquor after the condensation process of evaporation and purification of hydrochloric acid mother liquor, thereby preventing the demister from being blocked by liquid accumulation.

[0027] This application can change the length of the foam sleeve by controlling the extension and retraction drive to stretch or relax the foam sleeve, thereby changing the gap of the demister mesh and thus changing the demister efficiency. In the later stage of hydrochloric acid mother liquor evaporation, the water content is higher and the overall evaporation rate is faster. By reducing the demister efficiency, this change can be adapted.

[0028] The swing plate provided in this application can cooperate with the inner groove. During the expansion and contraction of the foam sleeve, the swing plate can be moved, swung, and pressed to make the swing plate strike the demisting mesh, thereby knocking down the droplets on the demisting mesh and preventing them from accumulating.

[0029] The bottom of the tank in this application is divided into upper and lower spaces by a partition plate. The packing storage tank set in the partition plate is filled with packing particles. The packing storage tank is equipped with a buffer box. Thus, after the packing particles enter or exit the packing storage tank, the number of packing particles in the packing storage tank changes. The more packing particles there are, the greater the pressure generated at the bottom of the tank below the packing storage tank. The steam generated at the bottom of the tank has to pass through a longer and narrower pore path of the packing particles. On the other hand, the weight of the packing particles themselves can squeeze the pores between the packing particles, while generating continuous pressure at the bottom of the tank, preventing the steam at the bottom of the tank from pressing open the packing particles again.

[0030] The packing particles of this application are provided with through holes, which can improve the ability of the packing particles to allow steam to pass through and prevent excessive packing particles from piling up in the packing storage tank and completely blocking the passage for steam to rise.

[0031] This application utilizes the L-shaped structure of the connecting rod, combined with the structure and connection relationship of the movable box, to drive the movable box to lower or swing upward, thereby controlling the movable box and the number of filler particles in the filler storage tank.

[0032] Based on the characteristic that the concentration of hydrochloric acid mother liquor gradually decreases and the proportion of water and impurities evaporating increases during the purification process of electronic-grade hydrochloric acid, this application designs an evaporation purification device. By gradually increasing the pressure of the vapor generated by the hydrochloric acid mother liquor during the evaporation purification process, the azeotropic point of the hydrochloric acid mother liquor is increased, and the proportion of water and impurities evaporating is reduced, thereby achieving a higher quality purification effect.

[0033] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained through the structures particularly pointed out in the description and the drawings.

[0034] It should be understood that the above summary and the following detailed description of the invention are exemplary and explanatory, and are intended to provide further explanation of the invention as claimed. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of an embodiment of the present invention.

[0036] Figure 2 This is a schematic diagram of a demister.

[0037] Figure 3 This is a cross-sectional view of the demister.

[0038] Figure 4 for Figure 3 Enlarged schematic diagram of part A.

[0039] Figure 5 This is an exploded view of the structure of the demister hidden behind its outer casing.

[0040] Figure 6 This is a structural schematic diagram of an embodiment of the tank.

[0041] Figure 7 This is a structural cross-sectional view of the tank.

[0042] Figure 8 This is a structural diagram of one of the filler storage slots and the buffer box.

[0043] Figure 9 This is a schematic diagram of the movable plate structure.

[0044] Figure 10 This is a schematic diagram showing the state of the movable panel after it has been raised.

[0045] Figure 11 This is a schematic diagram showing the state of the movable plate after it has descended.

[0046] Figure 12 This is a cross-sectional view of the filler particles. Detailed Implementation

[0047] To facilitate understanding by those skilled in the art, the structure of the present invention will now be described in further detail with reference to the accompanying drawings:

[0048] refer to Figure 1-12 An evaporation and condensation device for electronic-grade hydrochloric acid, comprising:

[0049] Evaporator 2 includes a tank 21, which is provided with a liquid inlet 211 and a vapor phase outlet 212. A heating tube 213 is provided at the bottom of the tank 21. In this embodiment, the hydrochloric acid mother liquor in the tank 21 is heated by the heating tube 213 at the bottom of the tank 21, thereby boiling the HCl and water in the hydrochloric acid mother liquor together, causing it to evaporate and flow out from the vapor phase outlet 212.

[0050] A pressure regulating device is provided inside the tank 21 to generate pressure at the bottom of the tank 21;

[0051] Condenser 3 includes a vapor phase inlet and a liquid phase outlet, wherein the vapor phase inlet is connected to the vapor phase outlet 212;

[0052] Demister 4 is connected to the liquid phase outlet. Demister 4 is equipped with a demisting efficiency adjustment device, which is used to adjust the interception efficiency of demister 4.

[0053] The working principle of this embodiment is as follows: hydrochloric acid mother liquor is evaporated through tank 21, and the evaporated vapor is fed into condenser 3 for condensation to obtain distilled liquid hydrochloric acid. The distilled liquid hydrochloric acid is then passed through demister 4 to intercept part of the uncondensed vapor phase, thereby obtaining purified hydrochloric acid. To address the characteristics of the hydrochloric acid mother liquor in tank 21, such as a decrease in concentration and an increase in azeotropic point during purification, as well as an increase in the proportion of water and impurities in the evaporated vapor phase, a pressure regulating device is used to generate pressure at the bottom of tank 21. This increases the azeotropic point of the hydrochloric acid mother liquor after the concentration decreases, making it difficult for impurities to volatilize and reducing the proportion of water evaporation. Furthermore, the interception efficiency of demister 4 can be adjusted through a demister efficiency regulating device. In the first half of the purification process of hydrochloric acid mother liquor, the boiling point is low and the HCl concentration in the vapor phase is high. At this time, the temperature difference between the vapor phase and condenser 3 is small, the condensation effect is poor, and a large amount of vapor phase remains after condensation. By reducing the pressure at the bottom of tank 21 through the pressure regulating device, the high-concentration hydrochloric acid mother liquor evaporates quickly, increasing the vapor phase generation rate. The demister efficiency regulating device improves the demister effect of demister 4, which can intercept more droplets. The intercepted droplets can be collected to form waste acid for partial HCl recovery. In the second half of the purification process of hydrochloric acid mother liquor, the boiling point is high and the water ratio in the vapor phase is high. By reducing the pressure at the bottom of tank 21 through the pressure regulating device, the vapor phase generation rate is reduced, and the proportion of water and impurities in the vapor phase is reduced. The demister efficiency regulating device reduces the demister effect of demister 4, which can prevent demister 4 from being overloaded and clogged.

[0054] The condensation equipment and demisting efficiency can be adjusted dimensionally using pressure regulating devices and demisting efficiency regulating devices.

[0055] Furthermore, the demister 4 includes an airflow duct 41, which is made of an elastic material and is filled with a demisting mesh 42.

[0056] The defogging efficiency adjustment device includes a spring 43 and a foam sleeve 44. The foam sleeve 44 is integrally formed with the spring 43 in a stretched state. When the spring 43 is not under force, it causes the foam sleeve 44 to contract together. The foam sleeve 44 is sleeved around the airflow duct 41. One end of the foam sleeve 44 is fixedly connected to the airflow duct 41, and the other end of the foam sleeve 44 is stretched or relaxed by a telescopic drive 45. When the foam sleeve 44 contracts, it creates wrinkles and contracts the airflow duct 41, thereby reducing the gap of the defogging mesh 42.

[0057] In this embodiment, the principle of the demister 4 is as follows: when tiny droplets flow with the airflow, they are intercepted and adhere to the surface of the demister mesh 42. The smaller the gaps in the demister mesh 42, the higher the droplet interception efficiency. The airflow duct 41 is made of an elastic material. After the foam sleeve 44 contracts, its hardness increases and multiple wrinkles are generated. The greater the compression of the foam sleeve 44, the thicker the wrinkles, thereby exerting different degrees of compression on the airflow duct 41. The inner diameter of the compressed airflow duct 41 becomes smaller, thus reducing the gaps in the demister mesh 42.

[0058] By controlling the extension and retraction drive 45 to stretch or loosen the foam sleeve 44, the length of the foam sleeve 44 can be changed, thereby altering the gap of the demister mesh 42. In the first half of the hydrochloric acid mother liquor evaporation stage, stretching the foam sleeve 44 with the extension and retraction drive 45 can shrink the foam sleeve 44, reducing the gap of the demister mesh 42 and improving its interception efficiency, thus intercepting more residual vapor phase. In the second half of the hydrochloric acid mother liquor evaporation stage, loosening the foam sleeve 44 with the extension and retraction drive 45 can expand the foam sleeve 44, increasing the gap of the demister mesh 42, reducing its interception efficiency, and allowing the vapor phase to pass through the demister 4 more easily, reducing the probability of liquid clogging the demister 4.

[0059] Furthermore, a layer of rubber hose is attached to the inner wall of the foam sleeve 44.

[0060] Furthermore, the rubber hose is provided with a plurality of working holes spaced apart along its axial direction, and the foam sleeve 44 is provided with an inner groove corresponding to the position of the working holes. The airflow duct 41 is provided with a plurality of swing plates 46 spaced apart along its axial direction. The top end of the swing plate 46 is fixedly connected to a working protrusion 461. The working protrusion 461 protrudes from the outer surface of the airflow duct 41. During the process of the other end of the foam sleeve 44 being stretched or relaxed by the telescopic drive member 45, the working holes and the inner groove pass through the working protrusion 461 in sequence, driving the working protrusion 461 to drive the swing plate 46 to swing, thereby agitating the demisting mesh 42.

[0061] The rubber hose can increase the rigidity of the inner wall of the foam sleeve 44, thereby generating higher hardness folds after the spring 43 contracts, improving the contraction effect on the airflow duct 41.

[0062] Simultaneously, through the designed working holes and inner grooves, the working protrusion 461 can be passed during the extension and retraction of the foam sleeve 44. The working protrusion 461 is first swung and pressed, then sinks into the inner groove. During this swaying and pressing motion, the working protrusion 461 can be tapped and pressed against the demister mesh 42, thereby knocking off the droplets gathered on the demister mesh 42 and preventing the droplets from accumulating into a planar structure, thus reducing the overall demisting effect of the demister 4. The rubber hose can enhance the swaying and pressing effect on the working protrusion 461.

[0063] Furthermore, an elastic element is connected between the swing plate 46 and the airflow duct 41, and the elastic element allows the swing plate 46 to adhere to the inner wall of the airflow duct 41 without being subjected to force.

[0064] When the elastic element can work the protrusion 461 back into the inner groove, it causes the swing plate 46 to return to the inner wall of the airflow duct 41, preventing the swing plate 46 from continuously sinking into and pressing the defogging mesh 42.

[0065] The pressure regulating device includes:

[0066] A partition plate 22 is disposed inside the tank 21 above the heating pipe 213. The partition plate 22 has a plurality of packing storage slots 221 arranged longitudinally. Each packing storage slot 221 has a movable plate 222 that moves up and down. Each movable plate 222 has a plurality of through holes for steam to pass through. The packing storage slots 221 are filled with packing particles 223. The packing particles 223 are used to generate pressure on the bottom of the tank 21, and the number of packing particles 223 is positively correlated with the pressure generated by the packing particles 223 on the bottom of the tank 21.

[0067] In this embodiment, the partition plate 22 separates the tank 21 into an upper part and a lower part. The heating pipe 213 is located below the partition plate 22. Therefore, the steam generated after the mother liquor is heated by the heating pipe 213 needs to pass through the through hole of the movable plate 222, then through the packing storage tank 221 to reach the top of the partition plate 22, and finally flow out through the vapor phase outlet 212.

[0068] Furthermore, the packing particles 223 are filled in the packing storage tank 221, with certain gaps between them. Steam must pass through these gaps to reach the partition plate 22. The more packing particles 223 there are, the higher the height they form after accumulation, and the longer the path the steam must traverse through the gaps, thus increasing the resistance to steam rise and locally increasing the steam pressure at the bottom of the tank 21. Simultaneously, the more packing particles 223 there are, the greater their total weight, which helps maintain local pressure at the bottom of the tank 21, preventing steam generated at the bottom from dislodging the packing particles 223 and releasing local pressure.

[0069] The buffer box 23 includes a fixed box 231 and a movable box 232. The fixed box 231 and the movable box 232 are connected. The fixed box 231 is arranged above the packing storage groove 221. The movable box 232 is hinged to one side of the packing storage groove 221. The end of the movable box 232 away from the packing storage groove 221 is inclined downward.

[0070] In this embodiment, the fixed box 231 can be positioned above the filler storage tank 221, limiting the filler particles 223 to only move through the opening of the fixed box 231 after being output upwards, preventing them from scattering to other positions on the partition plate 22. The movable box 232 is hinged to one side of the filler storage tank 221, allowing it to swing at its hinge point, either downwards or upwards. When the movable plate 222 moves upwards, it pushes some of the filler particles 223 out of the filler storage tank 221. At this time, the movable box 232 faces downwards, and the filler particles 223 flow into the movable box 232 through the opening of the fixed box 231 and are stored there. When the movable plate 222 moves downwards, it can cause the movable box 232 to flip upwards, and the filler particles 223 flow into the filler storage tank 221 through the opening of the movable box 232. This structure allows the number of packing particles 223 in the packing storage tank 221 to be changed by the up-and-down movement of the movable plate 222, thereby achieving pressure on the bottom of the tank 21.

[0071] A lifting drive component 24 is disposed at the bottom of the tank body 21. The telescopic end of the lifting drive component 24 is connected to the movable plate 222. The movable plate 222 is provided with a connecting rod 241 that drives the movable box body 232 to move. When the lifting drive component 24 extends, it drives the movable plate 222 and the connecting rod 241 to move upward, thereby gradually pushing the filler particles 223 into the movable box body 232. When the lifting drive component 24 retracts, it drives the movable plate 222 and the connecting rod 241 to move downward, thereby gradually pushing the filler particles 223 into the filler storage tank 221.

[0072] In the purification process of hydrochloric acid, during the initial stage of evaporation and purification, the concentration of hydrochloric acid in the mother liquor is high, for example, 32%. At this point... Figure 10 The raised movable plate 222 shown can reduce the amount of packing particles 223 in the packing storage tank 221, thereby reducing the vapor pressure of the packing particles 223 on the bottom of the tank 21, allowing both HCl and water to evaporate quickly. In the subsequent purification stage, the HCl content in the mother liquor decreases (for example, the hydrochloric acid concentration is 20.2%), while the impurity concentration increases. Figure 11 As shown, by lowering the movable plate 222, the number of packing particles 223 in the packing storage tank 221 can be increased, thereby increasing the steam pressure of the packing particles 223 on the bottom of the tank 21 and reducing the evaporation ratio of water and impurities in the mother liquor, thus resulting in a higher purity of the distilled vapor phase.

[0073] Furthermore, the filler particles 223 are made of quartz.

[0074] Furthermore, the partition plate 22 and the buffer box 23 are made of polytetrafluoroethylene, and the portion of the lifting drive component 24 located inside the tank 21 is coated with a polytetrafluoroethylene layer.

[0075] In this embodiment, the filler particles 223, the partition plate 22, and the buffer box 23 are made of or coated with an inert material, which can resist corrosion in an acidic environment and prevent the substances in the filler particles 223, the partition plate 22, and the buffer box 23 from reacting with hydrochloric acid to form new impurities.

[0076] Furthermore, the filler particles 223 have a spherical structure.

[0077] Furthermore, the filler particles 223 are provided with multiple through-holes.

[0078] Furthermore, the diameter of the filler particles 223 is 1 cm or more.

[0079] In this embodiment, the filler particles 223 have a spherical structure. After the filler particles 223 are stacked and stored in the filler storage tank 221, gaps naturally form between them, preventing complete blockage of the tank. Furthermore, the larger the diameter of the filler particles 223, the larger the gaps between them. Using filler particles 223 with a diameter of 1 cm or more ensures sufficient gaps between them, preventing excessive pressure from the mother liquor vapor pressure when the particles are stacked to a certain height, which would force the filler particles 223 open and eject them upwards. The filler particles 223 are provided with multiple through holes, increasing the space allowed for vapor passage.

[0080] Furthermore, the end of the movable box 232 partially overlaps with the end of the fixed box 231. The bottom end of the movable box 232, located outside the fixed box 231, is hinged to one side of the fixed box 231. The filling storage groove 221 protrudes from the partition plate 22. In the unloaded state, the end of the movable box 232 away from the fixed box 231 tilts downward and abuts against the partition plate 22. The connecting rod 241 moves upward and disengages from the movable box 232. The connecting rod 241 moves downward and presses the movable box 232, causing the movable box 232 to flip upward.

[0081] Furthermore, the connecting rod 241 has an L-shaped structure.

[0082] Furthermore, a shielding member is connected between the movable box 232 and the fixed box 231.

[0083] This structure allows the movable box 232 to form a seesaw-like structure. When the connecting rod 241 does not press one end of the movable box 232, the other end of the movable box 232 hangs down naturally to accommodate the filler particles 223 that are pushed out of the filler storage groove 221. When the movable box 232 is pressed, the other end of the movable box 232 can be lifted up, thereby retracting the filler particles 223 into the filler storage groove 221.

[0084] The shielding component can be a corrugated plate or a flexible plate, and is not limited here. It can shield the gap between the movable box 232 and the fixed box 231 to prevent the filler particles 223 from falling into the gap between the movable box 232 and the fixed box 231 and thus spilling onto the partition plate 22.

[0085] Furthermore, the control method includes: during the distillation process, the lifting drive 24 first rises to the highest point to reduce the number of packing particles 223 in the packing storage tank 221, and then the lifting drive 24 is controlled to gradually lower to increase the number of packing particles 223 in the packing storage tank 221.

[0086] Reducing the number of packing particles 223 in the packing storage tank 221 can rapidly evaporate a large amount of HCl and water from the high-concentration HCl mother liquor; reducing the number of packing particles 223 in the packing storage tank 221 can reduce the amount of water and impurities evaporated from the low-concentration HCl mother liquor, resulting in a distillate with higher purity.

[0087] It should be noted that any reference signs placed between parentheses in the claims should not be construed as limiting the claims. The word "comprising" does not exclude the presence of components or steps not listed in the claims. The word "a" or "an" preceding a component does not exclude the presence of a plurality of such components. The invention can be implemented by means of hardware comprising several different components and by means of a suitably programmed computer. In a unit claim enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

[0088] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0089] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0090] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms should not be construed as necessarily referring to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

Claims

1. An evaporation and condensation device for electronic-grade hydrochloric acid, characterized in that: include: Evaporator (2) includes tank (21), the tank (21) is provided with liquid inlet (211) and vapor phase outlet (212), and heating tube (213) is provided at the bottom of the tank (21). A pressure regulating device is installed inside the tank (21) to generate pressure at the bottom of the tank (21); The condenser (3) includes a vapor phase inlet and a liquid phase outlet, wherein the vapor phase inlet is connected to the vapor phase outlet (212). A demister (4) is connected to the liquid phase outlet. The demister (4) is equipped with a demister efficiency adjustment device, which is used to adjust the interception efficiency of the demister (4). The demister (4) includes an airflow duct (41) made of an elastic material and filled with a demister mesh (42). The demisting efficiency adjustment device includes a spring (43) and a foam sleeve (44). The foam sleeve (44) is integrally formed with the spring (43) in a stretched state. When the spring (43) is not under force, it causes the foam sleeve (44) to contract together. The foam sleeve (44) is sleeved around the airflow duct (41). One end of the foam sleeve (44) is fixedly connected to the airflow duct (41). The other end of the foam sleeve (44) is stretched or relaxed by a telescopic drive (45). After the foam sleeve (44) contracts, it generates wrinkles and contracts the airflow duct (41), thereby reducing the gap of the demisting mesh (42). The inner wall of the foam sleeve (44) is attached with a layer of rubber hose; The rubber hose is provided with a number of working holes at intervals along its axial direction. The foam sleeve (44) is provided with an inner groove corresponding to the position of the working hole. The airflow pipe (41) is provided with a number of swing plates (46) at intervals along its axial direction. The top of the swing plate (46) is fixedly connected to a working protrusion (461). The working protrusion (461) protrudes from the outer surface of the airflow pipe (41). During the process of stretching or relaxing the other end of the foam sleeve (44) through the telescopic drive (45), the working holes and the inner groove pass through the working protrusion (461) in sequence, driving the working protrusion (461) to drive the swing plate (46) to swing, thereby agitating the demisting mesh (42). An elastic element is connected between the swing plate (46) and the airflow duct (41), and the elastic element allows the swing plate (46) to be in contact with the inner wall of the airflow duct (41) without being subjected to force.

2. The evaporation and condensation equipment for electronic-grade hydrochloric acid according to claim 1, characterized in that: The pressure regulating device includes: A partition plate (22) is disposed inside the tank (21) above the heating pipe (213). The partition plate (22) is longitudinally provided with a plurality of packing storage slots (221). The packing storage slots (221) are provided with movable plates (222) that move up and down. The movable plates (222) are provided with a plurality of through holes for steam to pass through. The packing storage slots (221) are filled with packing particles (223). The packing particles (223) are used to generate pressure on the bottom of the tank (21), and the number of packing particles (223) is positively correlated with the pressure generated by the packing particles (223) on the bottom of the tank (21). The buffer box (23) includes a fixed box (231) and a movable box (232). The fixed box (231) and the movable box (232) are connected. The fixed box (231) surrounds the packing storage groove (221) above. The movable box (232) is hinged to one side of the packing storage groove (221). The end of the movable box (232) away from the packing storage groove (221) is inclined downward. A lifting drive component (24) is located at the bottom of the tank body (21). The telescopic end of the lifting drive component (24) is connected to the movable plate (222). The movable plate (222) is provided with a connecting rod (241) that drives the movable box body (232) to move. When the lifting drive component (24) extends, it drives the movable plate (222) and the connecting rod (241) to move upward, thereby gradually pushing the filler particles (223) into the movable box body (232). When the lifting drive component (24) retracts, it drives the movable plate (222) and the connecting rod (241) to move downward, thereby gradually pushing the filler particles (223) into the filler storage tank (221).

3. The evaporation and condensation equipment for electronic-grade hydrochloric acid according to claim 2, characterized in that: The filler particles (223) have a spherical structure and are provided with multiple through holes.

4. The evaporation and condensation equipment for electronic-grade hydrochloric acid according to claim 2, characterized in that: The end of the movable box (232) overlaps with the end of the fixed box (231). The bottom end of the movable box (232) located outside the fixed box (231) is hinged to one side of the fixed box (231). The filling storage groove (221) protrudes from the partition plate (22). In the unloaded state, the end of the movable box (232) away from the fixed box (231) tilts downward and abuts against the partition plate (22). The connecting rod (241) moves upward and disengages from the movable box (232). The connecting rod (241) moves downward and presses the movable box (232) to make the movable box (232) flip up.

5. The evaporation and condensation equipment for electronic-grade hydrochloric acid according to claim 2, characterized in that: A shielding element connects the movable box (232) and the fixed box (231).

6. The evaporation and condensation equipment for electronic-grade hydrochloric acid according to claim 2, characterized in that: The control method includes: during the distillation process, the lifting drive (24) is first raised to the highest point to reduce the number of packing particles (223) in the packing storage tank (221), and then the lifting drive (24) is controlled to gradually lower to increase the number of packing particles (223) in the packing storage tank (221).

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