Hydrofluoric acid rectification treatment purification apparatus

Abstract

The application discloses a hydrogen fluoride rectification treatment and purification equipment, and relates to the technical field of fractionation, which comprises a rectifying tower, an evaporator and a condenser. The rectifying tower is communicated with the evaporator. The rectifying tower and the condenser are communicated through a distillation pipe. A steam-water separator is communicated with the distillation pipe through a shunt pipe. A compressor is communicated with a gas outlet of the steam-water separator. A reflux pipe is communicated with a liquid outlet of the steam-water separator through a bus pipe. An output end of the compressor is communicated with an input end of a heat exchange pipe bundle of the evaporator. An output end of the heat exchange pipe bundle of the evaporator is communicated with the distillation pipe through a back cooling pipe. One end of the reflux pipe is communicated with a production pipe of an output end of the condenser. The other end of the reflux pipe is communicated with the rectifying tower. A variable-diameter pipe and a condensing element are arranged in the condenser. The variable-diameter pipe changes the cross-sectional area of the steam flow path, guides and concentrates the steam, improves the condensing effect of the condensing element on the steam, and further improves the condensing effect of the condenser on the steam.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fractionation, and in particular to a hydrogen fluoride rectification treatment and purification device. BACKGROUND

[0002] Hydrofluoric acid is a key chemical raw material, and has extremely high purity requirements in the fields of electronics and semiconductors. Rectification and purification is the core process for preparing high-purity hydrofluoric acid. The principle is as follows: industrial-grade hydrofluoric acid raw liquid is introduced into a rectification tower, and the raw liquid is evaporated to produce hydrofluoric acid vapor by heating at the bottom of the tower. The vapor rises and is in countercurrent contact with the reflux liquid in the tower, and impurities are separated by utilizing the differences in the boiling points of the components. Finally, high-purity hydrofluoric acid products are obtained by condensation in a tower top condenser.

[0003] The condenser is a key device in the purification process, and is responsible for the core function of condensing hydrofluoric acid vapor into liquid products. However, existing condensers mostly use fixed flow channel structures (such as tube-type and plate-type), and the cross-sectional area of the vapor heat exchange flow channel is fixed. This structure cannot adapt to changes in the vapor flow, and different condensers with different flow channel specifications need to be replaced during shutdown for different vapor flows, resulting in poor production continuity and increased equipment investment costs. SUMMARY

[0004] The purpose of the present application is to solve the problems in the prior art and to provide a scheme for a hydrogen fluoride rectification treatment and purification device.

[0005] To solve the above problems, the present application provides the following technical scheme: a hydrogen fluoride rectification treatment and purification device, comprising a rectification tower, an evaporator, and a condenser. The rectification tower is connected to the inlet of the evaporator through a liquid inlet pipe. The vapor outlet of the evaporator is connected to the vapor inlet of the rectification tower through a vapor pipe. The vapor outlet of the rectification tower is connected to the inlet of the condenser.

[0006] The condenser is provided with a multi-stage variable-diameter variable-diameter pipe, and a plurality of groups of condensing components with different covering diameters are arranged in the variable-diameter pipe. The variable-diameter pipe changes the cross-sectional area of the vapor flow path to guide and concentrate the vapor, thereby improving the condensing effect of the condensing components on the vapor and the condensing effect of the condenser on the vapor.

[0007] The variable diameter pipe comprises three straight sections with different diameters and two trumpet-shaped contraction sections, each of which is connected with one straight section with different diameters, one end of the contraction section with a larger diameter is provided with a separation layer, and the condenser is provided with a discharge port. The diameters of the three straight sections gradually decrease to adapt to the contraction sections after the diameter changes, and the condensed steam is concentrated again or the flow rate is slowed down, so that the steam is fully condensed by the subsequent condensing element. The separation layer is made of composite film material and has the effects of acid resistance, liquid permeation and steam barrier. The separation layer is used to separate the condensed liquid and steam. The liquid converges after passing through the separation layer and flows into the output pipe through the discharge port. The separation layer blocks the steam in the straight section and the contraction section, so that the steam cannot be discharged with the liquid, and the steam can be fully condensed in the straight section.

[0008] The large-diameter straight section is installed near the outlet of the condenser, and the small-diameter straight section is installed near the inlet of the condenser. The steam enters from the small-diameter straight section, is condensed by a group of condensing elements, and then the diameter of the contraction section gradually increases, so that the flow rate of the steam is slowed down, and the next group of condensing elements has sufficient time to condense the steam. The flow rate is slowed down several times, so that the steam is fully condensed in the condenser.

[0009] The small-diameter straight section is installed near the outlet of the condenser, and the large-diameter straight section is installed near the inlet of the condenser. The steam enters from the large-diameter straight section, is condensed by a group of condensing elements, and then the diameter of the contraction section gradually decreases, so that the flow rate of the steam is slowed down in the contraction section and gradually concentrated, so that the steam is fully contacted with the next group of condensing elements, so that the condensing elements fully condense the steam, and the condensing effect of the condensing elements on the steam is improved.

[0010] One end of the two straight sections at both ends is provided with a sealing disc connected with the inner wall of the condenser, and the other end of the contraction section connected with the small-diameter straight section is provided with a flow baffle, which is composed of two semicircles with different diameters. The semicircle with a larger diameter is connected with the inner wall of the condenser, and the semicircle with a smaller diameter forms a flow channel with the inside of the condenser. The sealing disc is used to connect the straight section and the condenser, and at the same time, the flow direction of the steam is closed, so that the steam can only pass through the straight section and the contraction section. When the condensed liquid flows out of the separation layer, the liquid will block the flow channel when flowing through the flow channel (i.e. there is no gap between the flow baffle and the inner wall of the condenser). When the separation layer has poor barrier effect on steam, part of the steam passes through the separation layer and flows to the outside of the variable diameter pipe. Due to the presence of the liquid, the steam is retained in the condenser, and finally the steam is condensed through heat exchange with the liquid and the outer wall of the straight section.

[0011] The outer side of each straight cylinder part of the variable diameter pipe is sleeved with two driving rings, the inside of the straight cylinder part is provided with a variable diameter mechanism, the driving ring provides power required for variable diameter, and the inside of the straight cylinder part is provided with a rubber sleeve covering the variable diameter mechanism.

[0012] The variable diameter mechanism is composed of multiple variable diameter units, the variable diameter unit includes a sleeve shell with a "C" shaped cross section and two variable diameter blocks slidingly installed on the sleeve shell, opposite ends of the two variable diameter blocks are provided with steps, and elastic members (not shown in the figure) are installed between the steps of the two variable diameter blocks; the elastic members are used to support the reset of the variable diameter blocks and the tightness of the two variable diameter blocks in contact in adjacent two variable diameter units; the elastic members are springs, spring plates or the like structure;

[0013] Two through grooves are formed on the straight cylinder part corresponding to the position of each sleeve shell, each driving ring is rotationally connected with the sleeve shell through a connecting rod, a linear motion mechanism is connected between the two driving rings, and the driving rings linearly move on the straight cylinder part. The linear motion mechanism (not shown in the figure) is a hydraulic rod structure or an electric rod structure wrapped with an acid-proof and high-temperature-resistant material. The driving ring is slidingly sleeved on the outside of the straight cylinder part, when it is necessary to change the cross-sectional area of the steam flow channel in the straight cylinder part and the structural density of the condensing member, the linear motion mechanism pushes the two driving rings in opposite directions or opposite directions; when the linear motion mechanism pushes the two driving rings in opposite directions, the sleeve shell moves towards the center of the straight cylinder part by the radial moving force of the two variable diameter blocks on the sleeve shell through the connecting rod during the approaching process, the cross-sectional area of the steam flow channel is reduced through the cooperation of multiple variable diameter units, and the condensing member is pressed by the variable diameter blocks through the rubber sleeve during the movement of the variable diameter unit, so that the condensing member shrinks along the axial direction, the density of the condensing member in the flow channel with reduced cross-sectional area is increased, and the condensing effect of the condensing member on the steam is improved.

[0014] Both ends of the inside of the condenser are provided with end plates with perforations, the centers of the two end plates are connected with a main shaft of a hollow pipe structure with closed two ends, a plurality of shaft sleeves are installed on the main shaft corresponding to each straight cylinder part of the variable diameter pipe, the condensing members are installed on each circumferential end face of the shaft sleeve, and multiple groups of condensing members with different diameters correspond to one straight cylinder part. The end plate supports the installation of the main shaft, and the main shaft supports the installation of the condensing member. The power supply wires of the condensing members are arranged in the main shaft and finally pass through the wire holes in the main shaft and the condenser.

[0015] The condensing member is made of two spring structures of metal materials in series, and the two free ends of the condensing member are electrically connected with an N-type semiconductor and a P-type semiconductor respectively.

[0016] The rectifying tower is communicated with the condenser through a distillation pipe, the distillation pipe is communicated with a water-gas separator through a shunt pipe, a gas outlet of the water-gas separator is communicated with a compressor, a liquid outlet of the water-gas separator is communicated with a reflux pipe through a collecting pipe, an output end of the compressor is communicated with an input end of a heat exchange pipe bundle of an evaporator through a compression pipe, an output end of the heat exchange pipe bundle of the evaporator is communicated with the distillation pipe through a back cooling pipe, one end of the reflux pipe is communicated with a production pipe of an output end of the condenser, and the other end of the reflux pipe is communicated with the rectifying tower, and a throttle valve is connected in series on the back cooling pipe. A part of steam at the top of the rectifying tower enters the condenser through the distillation pipe, and the other part enters the water-gas separator through the shunt pipe, the steam after water-gas separation enters the compressor, and after compression, the steam enters the heat exchange pipe bundle of the evaporator through the compression pipe, is used as a heat source, and the steam flowing out of the heat exchange pipe bundle enters the condenser through the throttle valve after the throttle valve, and is condensed in the condenser.

[0017] Compared with the prior art, the beneficial effects of the present application are that according to real-time changes of hydrogen fluoride acid steam flow and temperature, the cross-sectional area of the steam flow channel in the variable-diameter pipe is flexibly adjusted through the variable-diameter mechanism. When the steam flow increases, the cross-sectional area of the flow channel is increased to reduce the steam flow rate and prolong the heat exchange time; when the steam flow decreases, the cross-sectional area of the flow channel is reduced to increase the steam flow rate and avoid local retention; by changing the flow cross-sectional area, the steam is also fully condensed in the condenser.

[0018] Without stopping to replace the condenser, the flow channel cross-sectional area can be adjusted to adapt to changes in steam flow, without interrupting production, thereby improving production continuity, and also reducing equipment investment and maintenance costs. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is a overall perspective view of the present application;

[0020] Figure 2 It is a schematic view of the installation position of the variable-diameter pipe and the condensing part of the present application;

[0021] Figure 3 It is a schematic view of the installation position of the variable-diameter pipe and the condensing part of the present application;

[0022] Figure 4 It is an exploded view of the connection of the variable-diameter mechanism and the straight cylinder part of the present application;

[0023] Figure 5 It is an exploded view of the connection of the single variable-diameter unit and the driving ring of the present application;

[0024] Figure 6 It is an exploded view of the variable-diameter unit of the present application;

[0025] Figure 7 It is a structure view of the condensing part of the present application.

[0026] In the diagram: 1. Distillation column; 2. Evaporator; 3. Steam-water separator; 4. Compressor; 5. Condenser; 51. Straight section; 52. Contraction section; 53. Main shaft; 54. Baffle plate; 55. Separator layer; 56. Condenser; 57. Bushing; 58. End plate; 59. Drive ring; 510. Rubber sleeve; 511. Variable diameter unit; 512. Connecting rod; 513. Through groove; 514. Housing; 515. Variable diameter block; 6. Throttling valve; 7. Steam pipe; 8. Inlet pipe; 9. Compression pipe; 10. Cooling pipe; 11. Reflux pipe; 12. Diverter pipe; 13. Manifold pipe; 14. Distillation pipe; 15. Product pipe. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Example: Figure 1 - Figure 7 As shown, the present invention provides a technical solution: a hydrofluoric acid distillation purification device, comprising a distillation column 1, an evaporator 2, and a condenser 5. The distillation column 1 is provided with a liquid inlet, and the distillation column 1 is connected to the inlet of the evaporator 2 through a liquid inlet pipe 8. The vapor outlet of the evaporator 2 is connected to the vapor inlet of the distillation column 1 through a vapor pipe 7, and the vapor outlet of the distillation column 1 is connected to the inlet of the condenser 5 through a distillation pipe 14.

[0029] Temperature sensors, pressure sensors, flow sensors, and valves are installed on the pipeline (which consists of steam pipe 7, liquid inlet pipe 8, compression pipe 9, cooling return pipe 10, reflux pipe 11, branch pipe 12, manifold pipe 13, and distillation pipe 14, etc.). These are all standard configurations (not shown in the figure).

[0030] The heat source for the heat exchange tube bundle introduced into the evaporator 2 can be provided by external equipment or by the compressor 4. This can be freely switched according to actual needs.

[0031] The condenser 5 is equipped with a multi-stage reducing tube, and the reducing tube is equipped with multiple sets of condensing elements 56 with different covering diameters.

[0032] The reducing pipe includes three straight cylindrical sections 51 with different diameters and two flared constriction sections 52. Each end of the constriction section 52 is connected to a straight cylindrical section 51 with a different diameter. A partition layer 55 is provided at the end of the constriction section 52 with a larger diameter. The condenser 5 is provided with an outlet.

[0033] The diameters of the three straight sections 51 gradually decrease to accommodate the shrinkage section 52 after the diameter change. The shrinkage section 52, through the change in diameter, re-concentrates or slows down the flow rate of the condensed steam, thereby allowing the steam to be fully condensed by the subsequent condenser 56.

[0034] The separator 55 is made of a composite membrane material and has the effects of acid resistance, liquid permeation, and vapor barrier. The separator 55 is used to separate the condensed liquid and vapor. After the liquid passes through the separator 55, it converges and flows into the output pipe 15 through the outlet. The separator 55 blocks the vapor in the straight section 51 and the contraction section 52, so that the vapor cannot be discharged with the liquid and the vapor can be fully condensed in the straight section 51.

[0035] The condenser 5 has perforated end plates 58 installed at both ends inside. A hollow tube structure 53 with closed ends is connected to the center of the two end plates 58. Multiple bushings 57 are installed on the main shaft 53 corresponding to each straight cylindrical section 51. Condensing elements 56 are installed on each circumferential end face of the bushings 57, with multiple sets of condensing elements 56 of different diameters corresponding to one straight cylindrical section 51. The end plates 58 support the installation of the main shaft 53, which in turn supports the installation of the condensing elements 56 through the bushings 57.

[0036] The condenser 56 is made of two spring-structured metal materials connected in series. Its two free ends are electrically connected to an N-type semiconductor and a P-type semiconductor, respectively. The energizing wires of the condenser 56 are arranged in the spindle 53 and ultimately pass through wire holes on the spindle 53 and the condenser 5. The condenser 56 condenses steam using semiconductor refrigeration technology.

[0037] Example 1, as Figure 2 As shown, the small-diameter straight cylindrical section 51 is installed near the outlet of the condenser 5, and the large-diameter straight cylindrical section 51 is installed near the inlet of the condenser 5. Steam enters from the large-diameter straight cylindrical section 51, and after being condensed by a set of condensing elements 56, the diameter of the contraction section 52 gradually decreases, causing the steam to slow down its flow rate and gradually concentrate in the contraction section 52. This allows the steam to fully contact the next set of condensing elements 56, ensuring that the condensing elements 56 fully condense the steam and improving the condensation effect of the steam.

[0038] Example 2: The installation positions of the large-diameter and small-diameter straight cylindrical sections 51 are... Figure 2 The installation positions shown are reversed, specifically:

[0039] The large-diameter straight cylinder section 51 is installed near the outlet of the condenser 5, and the small-diameter straight cylinder section 51 is installed near the inlet of the condenser 5.

[0040] Steam enters from the small-diameter straight section 51, and after being condensed by a set of condensers 56, the diameter of the contraction section 52 gradually increases, slowing down the steam flow rate and allowing the next set of condensers 56 sufficient time to condense the steam. After multiple slowing down of the flow rate, the steam is fully condensed in the condenser 5.

[0041] Example 3, as Figure 2 , 4 As shown in Figure 5, one end of each of the two straight cylindrical sections 51 located at both ends is provided with a sealing disc that connects to the inner wall of the condenser 5. Each end of the constriction section 52 connecting the smaller diameter straight cylindrical section 51 is provided with a baffle plate 54. The baffle plate 54 is composed of two semicircles with different diameters. The larger diameter semicircle is connected to the inner wall of the condenser 5, and the smaller diameter semicircle forms a flow channel with the interior of the condenser 5.

[0042] The sealing disc is used to connect the straight section 51 and the condenser 5, and at the same time seals off the direction of steam flow, so that steam can only pass through the straight section 51 and the contraction section 52.

[0043] After the condensed liquid flows out from the partition layer 55, it will block the flow channel when it flows through it. When the partition layer 55 has a poor barrier effect on steam, some steam will flow through the partition layer 55 to the outside of the reducer. Due to the presence of the liquid, the steam will be retained in the condenser 5. With the heat exchange between the steam and the liquid and the outer wall of the straight cylinder 51, the steam will eventually condense.

[0044] Example 4 further optimizes the scheme based on Examples 1 to 3, such as... Figures 4-7 As shown, each straight cylindrical section 51 has two drive rings 59 slidably fitted on its outer side. The inside of the straight cylindrical section 51 is provided with a diameter changing mechanism. The drive rings 59 provide the power required for the diameter changing mechanism. The inside of the straight cylindrical section 51 is provided with a rubber sleeve 510 covering the diameter changing mechanism.

[0045] The diameter changing mechanism consists of multiple diameter changing units 511. Each diameter changing unit 511 includes a housing 514 with a "C" shaped cross section and two diameter changing blocks 515 that are slidably mounted on the housing 514. A step is provided at one end of each of the two diameter changing blocks 515, and an elastic element is installed between the two diameter changing blocks 515.

[0046] Two through slots 513 are provided on the straight cylindrical part 51 corresponding to the position of each sleeve 514. Each drive ring 59 is rotatably connected to the sleeve 514 through a connecting rod 512. A linear movement mechanism is connected between the two drive rings 59, and the drive rings 59 move linearly on the straight cylindrical part 51.

[0047] The linear motion mechanism is a hydraulic rod structure or an electric rod structure with an external coating of acid-resistant and high-temperature-resistant material.

[0048] When it is necessary to change the cross-sectional area of ​​the steam flow channel inside the straight section 51 and the structural density of the condenser 56, the control system controls the linear motion mechanism based on the data transmitted by the temperature sensor, flow sensor and other sensors, so that the linear motion mechanism drives the two drive rings 59 to move, and the linear motion mechanism pushes the two drive rings 59 in opposite directions or in the opposite direction.

[0049] When the cross-sectional area of ​​the flow channel is not changed, the condenser 56 is in a partially extended state;

[0050] When the cross-sectional area of ​​the flow channel is reduced and the structural density of the condenser 56 is increased, the linear movement mechanism pushes the two drive rings 59 toward each other and brings them closer together. During the closing process, the two drive rings 59 simultaneously apply a radial force to the housing 514 through the connecting rod 512, causing the housing 514 to move toward the center of the straight cylinder 51 along with the two variable diameter blocks 515. Through the cooperation of multiple variable diameter units 511, the cross-sectional area of ​​the steam flow channel is reduced. During the movement of the variable diameter unit 511, the variable diameter block 515 applies pressure to the condenser 56 through the rubber sleeve 510, causing the condenser 56 to contract along its own axial direction. This increases the density of the condenser 56 in the flow channel with a reduced cross-sectional area, thereby improving the condensation effect of the condenser 56 on the steam.

[0051] When the drive ring 59 is reset, the linear motion mechanism drives the drive ring 59 to reset, and the drive ring 59 drives the housing 514 to reset through the connecting rod 512, and the condenser 56 extends under its own elastic support.

[0052] Example 5: Based on Examples 1 to 4, the technical solution is optimized, such as... Figure 1 As shown, a steam-water separator 3 is connected to the distillation tube 14 via a splitter pipe 12. The gas outlet of the steam-water separator 3 is connected to a compressor 4. The liquid outlet of the steam-water separator 3 is connected to a reflux pipe 11 via a manifold 13. The output end of the compressor 4 is connected to the input end of the heat exchange tube bundle of the evaporator 2 via a compression pipe 9. The output end of the heat exchange tube bundle of the evaporator 2 is connected to the distillation tube 14 via a return cooling pipe 10. One end of the reflux pipe 11 is connected to the output pipe 15 of the condenser 5, and the other end of the reflux pipe 11 is connected to the distillation column 1. A throttling valve 6 is connected in series on the return cooling pipe 10.

[0053] The working principle of this invention is as follows: The liquid in the distillation column 1 enters the evaporator 2 through the inlet pipe 8, and the generated steam enters the bottom of the distillation column 1 through the steam pipe 7. The steam rises from the bottom to the top of the distillation column 1. After the steam at the top of the distillation column 1 enters the distillation tube 14, part of it enters the condenser 5 through the distillation tube 14. After being condensed by the condenser 56, part of the liquid produced is produced and part is returned. The other part of the steam enters the steam-water separator 3 through the split pipe 12. After being separated by steam and water, the steam enters the compressor 4. After being compressed, it enters the heat exchange tube bundle of the evaporator 2 through the compression pipe 9 and is used as a heat source. The steam flowing out of the heat exchange tube bundle passes through the throttling valve 6 and then flows back to the condenser 5 through the return cooling pipe 10 for condensation.

[0054] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A hydrofluoric acid distillation purification device, characterized in that: It includes a distillation column (1), an evaporator (2) and a condenser (5). The distillation column (1) is connected to the inlet of the evaporator (2) through a liquid inlet pipe (8). The steam outlet of the evaporator (2) is connected to the steam inlet of the distillation column (1) through a steam pipe (7). The steam outlet of the distillation column (1) is connected to the inlet of the condenser (5). The condenser (5) is provided with a multi-stage variable diameter tube, and the variable diameter tube is provided with a multi-set condenser element (56) with different covering diameters. The variable diameter tube includes three straight sections (51) with different diameters and two flared constricted sections (52). Two drive rings (59) are fitted on the outside of each straight section (51) of the variable diameter pipe. A variable diameter mechanism is provided inside the straight section (51). The drive rings (59) provide the power required for the variable diameter mechanism to change the diameter. A rubber sleeve (510) covering the variable diameter mechanism is provided inside the straight section (51). The diameter changing mechanism is composed of multiple diameter changing units (511). Each diameter changing unit (511) includes a "C" shaped housing (514) and two diameter changing blocks (515) slidably mounted on the housing (514). A step is provided at one end of each of the two diameter changing blocks (515), and an elastic element is installed between the two diameter changing blocks (515). Two through slots (513) are provided on the straight cylindrical part (51) corresponding to the position of each sleeve (514). Each drive ring (59) is rotatably connected to the sleeve (514) through a connecting rod (512). A linear movement mechanism is connected between the two drive rings (59), and the drive rings (59) move linearly on the straight cylindrical part (51).

2. The hydrofluoric acid distillation purification equipment according to claim 1, characterized in that: The contraction section (52) is connected to a straight cylindrical section (51) with different diameters at both ends. The end of the contraction section (52) with a larger diameter is provided with a partition layer (55). The condenser (5) is provided with a discharge port.

3. The hydrofluoric acid distillation purification equipment according to claim 2, characterized in that: The large-diameter straight cylindrical section (51) is installed near the outlet of the condenser (5), and the small-diameter straight cylindrical section (51) is installed near the inlet of the condenser (5).

4. The hydrofluoric acid distillation purification equipment according to claim 2, characterized in that: The smaller diameter straight cylindrical section (51) is installed near the outlet of the condenser (5), and the larger diameter straight cylindrical section (51) is installed near the inlet of the condenser (5).

5. The hydrofluoric acid distillation purification apparatus according to any one of claims 2-4, characterized in that: The two straight cylindrical sections (51) located at both ends are provided with a sealing plate connecting to the inner wall of the condenser (5) at one end. The constriction section (52) connecting the small diameter straight cylindrical section (51) is provided with a baffle plate (54) at each end. The baffle plate (54) is composed of two semicircles with different diameters. The larger diameter semicircle is connected to the inner wall of the condenser (5), and the smaller diameter semicircle forms a flow channel between itself and the interior of the condenser (5).

6. The hydrofluoric acid distillation purification equipment according to claim 1, characterized in that: The condenser (5) has perforated end plates (58) installed at both ends inside. The two end plates (58) are connected to a main shaft (53) with a hollow tube structure closed at both ends. Multiple bushings (57) are installed on the main shaft (53) at the position of each straight section (51) of the strain diameter tube. The condensing element (56) is installed on each circumferential end face of the bushing (57). Multiple sets of condensing elements (56) with different diameters correspond to one straight section (51).

7. A hydrofluoric acid distillation purification apparatus according to claim 1 or 6, characterized in that: The condenser (56) is made of two strands of metal material connected in series with a spring structure, and the two free ends of the condenser (56) are electrically connected to an N-type semiconductor and a P-type semiconductor, respectively.

8. The hydrofluoric acid distillation purification equipment according to claim 1, characterized in that: The distillation column (1) and the condenser (5) are connected by a distillation tube (14). A steam-water separator (3) is connected to the distillation tube (14) by a splitter tube (12). The gas outlet of the steam-water separator (3) is connected to a compressor (4). The liquid outlet of the steam-water separator (3) is connected to a reflux tube (11) by a manifold (13). The output end of the compressor (4) is connected to the input end of the heat exchange tube bundle of the evaporator (2) by a compression tube (9). The output end of the heat exchange tube bundle of the evaporator (2) is connected to the distillation tube (14) by a return cooling tube (10). One end of the reflux tube (11) is connected to the output tube (15) of the condenser (5). The other end of the reflux tube (11) is connected to the distillation column (1). A throttling valve (6) is connected in series on the return cooling tube (10).

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