Electronic-grade hydrochloric acid preparation device and preparation method

Abstract

The invention discloses an electronic grade hydrochloric acid preparation device and method, and relates to the technical field of hydrochloric acid preparation, the electronic grade hydrochloric acid preparation device comprises a raw material pump, a primary rectifying tower and a secondary rectifying tower, the bottom of the primary rectifying tower is provided with a primary reboiler, the bottom of the secondary rectifying tower is provided with a secondary reboiler, and the secondary reboiler is provided with a secondary reboiler. A cooler and a communicating pipe are connected between the first-stage rectifying tower and the second-stage rectifying tower, the first-stage reboiler and the second-stage reboiler are both connected with a feeding pipe and a steam pipe, the feeding pipe on the first-stage reboiler is connected with a raw material pump, the feeding pipe on the second-stage rectifying tower is connected with the communicating pipe, and the steam pipe is connected with a steam pipe. A first-stage heat exchanger and a second-stage heat exchanger are arranged at the bottoms of the first-stage rectifying tower and the second-stage rectifying tower respectively, the two feeding pipes penetrate through the adjacent heat exchangers respectively, the first-stage reboiler heats a hydrochloric acid solution, liquid-phase hydrochloric acid with a low boiling point is evaporated firstly, a doped solution with a high boiling point is evaporated later, and the second-stage reboiler heats the mixed solution; and steam generated by evaporation enters the first-stage rectifying tower through a feeding pipe.

Description

Technical Field

[0001] The invention relates to the technical field of hydrochloric acid preparation, and in particular to an electronic grade hydrochloric acid preparation device and a preparation method. Background Art

[0002] Electronic-grade hydrochloric acid is a core chemical in high-end electronic industries such as semiconductor manufacturing and photovoltaic cells. Its purity must reach PPT level to avoid metal ion contamination. The traditional preparation process relies on multi-stage purification by distillation towers, but there are significant defects in practical applications.

[0003] Firstly, the separation efficiency of hydrochloric acid gas and impurities during the distillation process is limited by the mass transfer effect of the packing plate. Conventional packing structures are prone to flooding or channeling, resulting in insufficient vapor-liquid contact area. It is necessary to extend the residence time or increase the tower height to meet the purity requirements. Secondly, the reboiler at the bottom of the distillation tower needs to continuously consume a large amount of steam to maintain the vaporization temperature, and the energy utilization rate is low. The waste acid liquid containing 60-80°C waste heat directly enters the cooling system, resulting in a waste of heat energy. Summary of the invention

[0004] The object of the present invention is to provide an electronic grade hydrochloric acid preparation device and a preparation method to solve the problems raised in the prior art.

[0005] To achieve the above-mentioned object, the present invention provides the following technical scheme: an electronic grade hydrochloric acid preparation device, comprising a raw material pump, a primary distillation tower and a secondary distillation tower, a primary reboiler is arranged at the bottom of the primary distillation tower, a secondary reboiler is arranged at the bottom of the secondary distillation tower, a cooler and a communication pipe are connected between the primary distillation tower and the secondary distillation tower, a feed pipe and a steam pipe are connected to the primary reboiler and the secondary reboiler, the feed pipe on the primary reboiler is connected to the raw material pump, and the secondary distillation tower is connected to the feed pipe on the primary reboiler. The feed pipe is connected to the communication pipe. A primary heat exchanger and a secondary heat exchanger are respectively arranged at the bottom of the primary distillation tower and the secondary distillation tower. The two feed pipes respectively penetrate the adjacent heat exchangers. The hydrochloric acid solution to be purified is stored in a raw material tank. The raw material pump extracts the hydrochloric acid solution and transports it to the primary reboiler through the feed pipe. The primary reboiler heats the hydrochloric acid solution. The low-boiling-point liquid hydrochloric acid evaporates first, and the high-boiling-point doping solution evaporates later. The steam generated by the evaporation enters the primary distillation tower through the feed pipe.

[0006] Furthermore, the first-level distillation tower includes a bottom tower cylinder, several middle tower cylinders and a top tower cylinder, several middle tower cylinders are connected between the bottom tower cylinder and the top tower cylinder, the bottom tower cylinder, the middle tower cylinder and the top tower cylinder are connected by flanges and bolts, and sealing rings are arranged between the flanges.

[0007] Furthermore, an air inlet is provided at the bottom of the bottom tower tube, a waste liquid hole is provided on one side of the bottom of the bottom tower tube, the air inlet is connected to the first-level reboiler through a steam pipe, the waste liquid hole is connected to the first-level heat exchanger through a waste liquid pipe, an air outlet is provided at the top of the top tower tube, an air outlet pipe is connected to the air outlet, a reflux hole is provided on one side of the top of the top tower tube, the steam flows upward in the first-level distillation tower, the packing plate intercepts the acid foam and particulate matter in the steam, the steam reaches the top of the first-level distillation tower and enters the cooler through the air outlet pipe, the high-boiling point vapor phase is first liquefied in the cooler, and the liquid phase flows back into the first-level distillation tower through the reflux pipe, the low-boiling point vapor phase is purified hydrochloric acid vapor, and the hydrochloric acid vapor enters the connecting pipe after liquefaction and flows into the secondary distillation tower.

[0008] Furthermore, several groups of packing components are evenly arranged in the bottom tower, several middle towers and top tower, each group of packing components includes a packing plate and several dripping needles, the packing plate is in the shape of an inverted bowl, a through hole is opened in the middle of the packing plate, and several annular capillary ring grooves are opened on the top of the packing plate. There is a gap between the packing plate and the wall of the tower, and the packing plate is installed on the wall of the tower through a bracket. The liquid phase of the refluxed doping solution is the original liquid phase X N-1 The steam generated in the first-stage reboiler is the original steam phase Y N+1 , original liquid phase X N-1 It flows downward along the cylinder wall, drips onto the Nth packing plate through the drainage of the dripping needle, and mixes with the original steam on the Nth packing plate. N+1 Encounter, cooling liquid phase X N-1 When heated again, the original liquid phase N-1 The low boiling point hydrochloric acid solution in the solution is evaporated, and part of the vaporized low boiling point hydrochloric acid solution is mixed with the original steam. N+1 Formation of new vapor phase Y N Rising, original steam phase Y N+1 The impurity solution with medium and high boiling points is partially condensed, and the partially condensed impurity solution with boiling points is mixed with the original solution. N-1 Formation of new liquid phase X N decline.

[0009] Furthermore, a plurality of the dripping needles are evenly distributed on the wall of the tower in an annular shape, a plurality of the dripping needles are arc-shaped, and a plurality of the dripping needles are located above the packing plate. The structure and internal arrangement of the secondary distillation tower are the same as those of the primary distillation tower. In the primary distillation tower, the low boiling point of hydrochloric acid and the high boiling point of the doping solution are utilized to pass the original liquid phase X N-1 Partial vaporization, original vapor phase Y N+1 By partial condensation, hydrochloric acid is purified step by step, and the doping solution is separated step by step. After the distillation process, the new vapor phase Y N The purity of hydrochloric acid in the vapor phase is greater than that of the original N+1 Purity of hydrochloric acid in the new liquid phase XN The hydrochloric acid concentration in the original liquid phase is less than N-1 The concentration of hydrochloric acid in the solution increases with the light component and decreases with the heavy component. The new liquid phase X N The concentration of hydrochloric acid in the solution approaches 0, and the new vapor phase Y N The concentration of hydrochloric acid is close to 100%.

[0010] Furthermore, a water-cooled circulation pipe is arranged inside the cooler, and two through holes are opened on one side of the cooler close to the primary distillation tower. The two through holes are respectively located on the upper and lower sides of the water-cooled circulation pipe. The upper through hole is connected to the exhaust pipe, and the lower through hole is connected to a reflux pipe, and the reflux pipe is connected to the reflux hole of the primary distillation tower.

[0011] Furthermore, a triangular pad is provided inside the cooler, the short hypotenuse of the triangular pad is located on the side close to the primary distillation tower, and the long hypotenuse of the triangular pad is located on the side close to the secondary distillation tower. A liquid outlet is provided at the bottom of the cooler away from the primary distillation tower, and the liquid outlet is connected to a communication pipe. A plurality of filters are provided in the middle of the communication pipe. The air outlet pipe of the secondary distillation tower is also connected to the cooler. The installation method of the cooler on the secondary distillation tower is the same as that of the primary distillation tower. The triangular pad cools the new vapor phase Y N It plays the role of diversion, diverting part of the liquid phase to the primary distillation tower for distillation and purification, and the new vapor phase Y N After liquefaction, it enters the connecting pipe. The filter on the connecting pipe filters the liquefied hydrochloric acid solution again to block impurities. The hydrochloric acid is heated in the secondary reboiler, undergoes a second round of extraction in the secondary distillation tower, and is then output to the absorption tower and other subsequent processing steps.

[0012] Further, the primary heat exchanger includes a heat exchange capsule, a waste pipe and a spiral baffle plate, the spiral baffle plate is located inside the heat exchange capsule, the feed pipe connected to the primary reboiler passes through the heat exchange capsule, the spiral baffle plate is sealed and connected to the tube wall of the feed pipe and the inside of the heat exchange capsule, the waste liquid pipe at the bottom of the primary distillation tower is connected to the heat exchange capsule, the waste pipe is connected to the side of the heat exchange capsule away from the waste liquid pipe, the structure and installation method of the secondary heat exchanger are the same as those of the primary heat exchanger, and the new liquid phase X finally produced N Flows to the bottom of the primary heat exchanger and flows into the heat exchange bag through the waste liquid pipe at the bottom. N There is still a certain temperature. After flowing through the spiral baffle in the heat exchange bag, it is discharged through the waste pipe. In the heat exchange bag, the new liquid phase X N The raw material is fully contacted and exchanged with the raw material feed pipe to preheat the raw material, thereby saving the heat energy of the reboiler and achieving the effect of energy saving and environmental protection.

[0013] The preparation method used in an electronic grade hydrochloric acid preparation device comprises the following steps: S1: The hydrochloric acid raw material is transported to the primary reboiler through the feed pipe by the raw material pump, the primary reboiler is indirectly heated by steam, and the generated vapor phase hydrochloric acid is transported to the primary distillation tower through the steam pipe; S2: The first-stage distillation tower contains a packing layer inside, and the particles in the steam are intercepted after passing through the packing layer; S3: The hydrochloric acid vapor of the distillation is cooled by the cooler, and the liquefied hydrochloric acid liquid phase is transported to the secondary reboiler through the connecting pipe. The secondary reboiler is indirectly heated by steam, and the generated vapor phase hydrochloric acid is transported to the secondary distillation tower through the steam pipe; S4: The secondary distillation tower contains a packing layer inside, and the particulate matter in the hydrochloric acid vapor is intercepted after passing through the packing layer. The hydrochloric acid vapor of the secondary distillation is cooled by a cooler and then transported to the subsequent absorption tower treatment process.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. Taking advantage of the low boiling point of hydrochloric acid and the high boiling point of the doping solution, the original liquid phase N-1 Partial vaporization, original vapor phase Y N+1 By partial condensation, hydrochloric acid is purified step by step, and the doping solution is separated step by step. After the distillation process, the new vapor phase Y N The purity of hydrochloric acid in the vapor phase is greater than that of the original N+1 Purity of hydrochloric acid in the new liquid phase X N The hydrochloric acid concentration in the original liquid phase is less than N-1 The concentration of hydrochloric acid in the solution increases with the light component and decreases with the heavy component. The new liquid phase X N The concentration of hydrochloric acid in the solution approaches 0, and the new vapor phase Y N The concentration of hydrochloric acid is close to 100%.

[0015] 2. The final new liquid phase X N There is still a certain temperature. After flowing through the spiral baffle in the heat exchange bag, it is discharged through the waste pipe. In the heat exchange bag, the new liquid phase X N The raw material is fully contacted and exchanged with the raw material feed pipe to preheat the raw material, thereby saving the heat energy of the reboiler and achieving the effect of energy saving and environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The overall structure of the present invention is shown in FIG. Figure 1 ; Figure 2 The overall structure of the present invention is shown in FIG. Figure 2 ; Figure 3It is a schematic diagram of the internal structure of the cooler of the present invention; Figure 4 It is a partial structural schematic diagram of the present invention; Figure 5 This is a schematic diagram of the internal structure of the heat exchange bag of the present invention; Figure 6 The internal structure of the distillation tower of the present invention is shown in FIG. Figure 1 ; Figure 7 The internal structure of the distillation tower of the present invention is shown in FIG. Figure 2 .

[0017] In the figure: 1. raw material pump; 2. primary reboiler; 3. primary distillation tower; 4. cooler; 5. secondary reboiler; 6. secondary distillation tower; 7. connecting pipe; 8. filter; 9. primary heat exchanger; 10. secondary heat exchanger; 11. feed pipe; 12. heat exchange bag; 13. waste liquid pipe; 14. waste pipe; 15. spiral baffle; 16. outlet pipe; 17. reflux pipe; 18. water-cooled circulation pipe; 19. triangular pad; 20. steam pipe; 21. packing plate; 22. drip needle; 23. flange; 24. bottom tower; 25. top tower; 26. middle tower. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] Example: Figure 1-Figure 7 As shown, the present invention provides a technical solution, an electronic grade hydrochloric acid preparation device, comprising a raw material pump 1, a primary distillation tower 3 and a secondary distillation tower 6, a primary reboiler 2 is arranged at the bottom of the primary distillation tower 3, a secondary reboiler 5 is arranged at the bottom of the secondary distillation tower 6, a cooler 4 and a communication pipe 7 are connected between the primary distillation tower 3 and the secondary distillation tower 6, a feed pipe 11 and a steam pipe 20 are connected to the primary reboiler 2 and the secondary reboiler 5, the feed pipe 11 on the primary reboiler 2 is connected to the raw material pump 1, and the feed pipe 11 on the secondary distillation tower 6 is connected to the raw material pump 1. The feed pipe 11 is connected to the communication pipe 7. A primary heat exchanger 9 and a secondary heat exchanger 10 are respectively arranged at the bottom of the primary distillation tower 3 and the secondary distillation tower 6. The two feed pipes 11 respectively penetrate the adjacent heat exchangers. The hydrochloric acid solution to be purified is stored in the raw material tank. The raw material pump 1 extracts the hydrochloric acid solution and transports it to the primary reboiler 2 through the feed pipe 11. The primary reboiler 2 heats the hydrochloric acid solution. The low-boiling-point liquid hydrochloric acid evaporates first, and the high-boiling-point doping solution evaporates later. The steam generated by the evaporation enters the primary distillation tower 3 through the feed pipe 11.

[0020] The primary distillation tower 3 includes a bottom tower barrel 24, several middle tower barrels 26 and a top tower barrel 25, wherein the several middle tower barrels 26 are connected between the bottom tower barrel 24 and the top tower barrel 25, and the bottom tower barrel 24, the middle tower barrel 26 and the top tower barrel 25 are connected by flanges 23 and bolts, and sealing rings are arranged between the flanges 23. An air inlet is provided at the bottom of the bottom tower barrel 24, and a waste liquid hole is provided on one side of the bottom of the bottom tower barrel 24. The air inlet is connected to the primary reboiler 2 through a steam pipe 20, and the waste liquid hole is connected to the primary heat exchanger 9 through a waste liquid pipe 13. The top of the tower 25 is provided with an air outlet hole, to which the air outlet pipe 16 is connected, and one side of the top of the top tower 25 is provided with a reflux hole, and a plurality of groups of packing components are evenly arranged in the bottom tower 24, the middle towers 26 and the top tower 25, and each group of packing components includes a packing plate 21 and a plurality of dripping needles 22, and the packing plate 21 is in the shape of an inverted bowl, and a through hole is provided in the middle of the packing plate 21, and a plurality of annular capillary ring grooves are provided on the top of the packing plate 21, and there is a gap between the packing plate 21 and the wall of the tower, and the packing plate 21 is installed on the wall of the tower through a bracket. The steam flows upward in the primary distillation tower 3, and the packing plate 21 intercepts the acid foam and particulate matter in the steam. The steam reaches the top of the primary distillation tower 3 and enters the cooler 4 through the outlet pipe 16. The high-boiling point vapor phase is first liquefied in the cooler 4, and the liquid phase flows back into the primary distillation tower 3 through the reflux pipe 17. The low-boiling point vapor phase is the purified hydrochloric acid vapor. After the hydrochloric acid vapor is liquefied, it enters the communication pipe 7 and flows into the secondary distillation tower 6. The refluxed doping solution liquid phase is the original liquid phase X N-1 The steam generated in the primary reboiler 2 is the original steam phase Y N+1 , original liquid phase X N-1 It flows downward along the cylinder wall, drips onto the Nth packing plate 21 through the drainage of the dripping needle 22, and mixes with the original steam on the Nth packing plate 21. N+1 Encounter, cooling liquid phase X N-1 When heated again, the original liquid phase N-1 The low boiling point hydrochloric acid solution in the solution is evaporated, and part of the vaporized low boiling point hydrochloric acid solution is mixed with the original steam. N+1 Formation of new vapor phase Y N Rising, original steam phase Y N+1 The impurity solution with medium and high boiling points is partially condensed, and the partially condensed impurity solution with boiling points is mixed with the original solution. N-1 Formation of new liquid phase X N decline.

[0021] A plurality of dripping needles 22 are evenly distributed in a ring shape on the wall of the tower, a plurality of dripping needles 22 are arc-shaped, and a plurality of dripping needles 22 are located above the packing plate 21. The structure and internal arrangement of the secondary distillation tower 6 are the same as those of the primary distillation tower 3. In the primary distillation tower 3, the low boiling point of hydrochloric acid and the high boiling point of the doping solution are utilized to pass through the original liquid phase X N-1 Partial vaporization, original vapor phase Y N+1 By partial condensation, hydrochloric acid is purified step by step, and the doping solution is separated step by step. After the distillation process, the new vapor phase Y N The purity of hydrochloric acid in the vapor phase is greater than that of the original N+1 Purity of hydrochloric acid in the new liquid phase X N The hydrochloric acid concentration in the original liquid phase is less than N-1 The concentration of hydrochloric acid in the solution increases with the light component and decreases with the heavy component. The new liquid phase X N The concentration of hydrochloric acid in the solution approaches 0, and the new vapor phase Y N The concentration of hydrochloric acid is close to 100%.

[0022] A water-cooled circulation pipe 18 is arranged inside the cooler 4. Two through holes are provided on one side of the cooler 4 close to the primary distillation tower 3. The two through holes are respectively located on the upper and lower sides of the water-cooled circulation pipe 18. The through hole located at the upper side is connected to the gas outlet pipe 16. The through hole located at the lower side is connected to the reflux pipe 17. The reflux pipe 17 is connected to the reflux hole of the primary distillation tower 3. A triangular pad 19 is also arranged inside the cooler 4. The short hypotenuse of the triangular pad 19 is located on the side close to the primary distillation tower 3, and the long hypotenuse of the triangular pad 19 is located on the side close to the secondary distillation tower 6. A liquid outlet is provided at the bottom of the cooler 4 on the side away from the primary distillation tower 3. The liquid outlet is connected to the communication pipe 7. Several filters 8 are arranged in the middle of the communication pipe 7. The gas outlet pipe 16 of the secondary distillation tower 6 is also connected to the cooler 4. The installation method of the cooler 4 on the secondary distillation tower 6 is the same as that of the primary distillation tower 3. The triangular pad 19 cools the new vapor phase Y N It plays the role of diverting, diverting part of the liquid phase to the primary distillation tower 3 for distillation and purification, and the new vapor phase Y N After liquefaction, it enters the connecting pipe 7. The filter 8 on the connecting pipe 7 filters the liquefied hydrochloric acid solution again to block impurities. The hydrochloric acid is heated by the secondary reboiler 5, undergoes a second round of extraction in the secondary distillation tower 6, and is then output to the absorption tower and other subsequent processing steps.

[0023] The primary heat exchanger 9 includes a heat exchange capsule 12, a waste pipe 14 and a spiral baffle 15. The spiral baffle 15 is located inside the heat exchange capsule 12. The feed pipe 11 connected to the primary reboiler 2 passes through the heat exchange capsule 12. The spiral baffle 15 is sealed and connected to the wall of the feed pipe 11 and the inside of the heat exchange capsule 12. The waste liquid pipe 13 at the bottom of the primary distillation tower 3 is connected to the heat exchange capsule 12. The waste pipe 14 is connected to the side of the heat exchange capsule 12 away from the waste liquid pipe 13. The structure and installation method of the secondary heat exchanger 10 are the same as those of the primary heat exchanger 9. The new liquid phase X generated in the end N Flows to the bottom of the primary heat exchanger 9, flows into the heat exchange bag 12 through the waste liquid pipe 13 at the bottom, and the final new liquid phase X N Still at a certain temperature, it flows through the spiral baffle plate 15 in the heat exchange capsule 12 and is discharged through the waste pipe 14. In the heat exchange capsule 12, the new liquid phase X N The raw material is fully contacted and exchanged with the raw material feed pipe 11 to preheat the raw material, thereby saving the heat energy of the reboiler and achieving the effect of energy saving and environmental protection.

[0024] The preparation method used in an electronic grade hydrochloric acid preparation device comprises the following steps: S1: The hydrochloric acid raw material is transported to the primary reboiler 2 through the feed pipe 11 by the raw material pump 1. The primary reboiler 2 is indirectly heated by steam, and the generated vapor phase hydrochloric acid is transported to the primary distillation tower 3 through the steam pipe 20; S2: The first-stage distillation tower 3 contains a packing layer inside, and the particles in the steam are intercepted after passing through the packing layer; S3: The temperature of the distilled hydrochloric acid vapor is reduced by the cooler 4, and the liquefied hydrochloric acid liquid phase is transported to the secondary reboiler 5 through the communication pipe 7. The secondary reboiler 5 is indirectly heated by steam, and the generated vapor phase hydrochloric acid is transported to the secondary distillation tower 6 through the steam pipe 20; S4: The secondary distillation tower 6 contains a packing layer inside, and the particulate matter in the hydrochloric acid vapor is intercepted after passing through the packing layer. The hydrochloric acid vapor of the secondary distillation is cooled by the cooler 4 and then transported to the subsequent absorption tower treatment process.

[0025] The working principle of the present invention is as follows: the hydrochloric acid solution to be purified is stored in a raw material tank, the raw material pump 1 extracts the hydrochloric acid solution and transports it to the primary reboiler 2 through the feed pipe 11, the primary reboiler 2 heats the hydrochloric acid solution, the low-boiling point liquid phase hydrochloric acid evaporates first, and the high-boiling point doping solution evaporates later, and the steam generated by the evaporation enters the primary distillation tower 3 through the feed pipe 11.

[0026] The steam flows upward in the primary distillation tower 3, and the packing plate 21 intercepts the acid foam and particulate matter in the steam. The steam reaches the top of the primary distillation tower 3 and enters the cooler 4 through the outlet pipe 16. The high-boiling point vapor phase is first liquefied in the cooler 4, and the liquid phase flows back into the primary distillation tower 3 through the reflux pipe 17. The low-boiling point vapor phase is the purified hydrochloric acid vapor. After liquefaction, the hydrochloric acid vapor enters the communication pipe 7 and flows into the secondary distillation tower 6.

[0027] The refluxed doping solution liquid phase is the original liquid phase X N-1 The steam generated in the primary reboiler 2 is the original steam phase Y N+1 , original liquid phase X N-1 It flows downward along the cylinder wall, drips onto the Nth packing plate 21 through the drainage of the dripping needle 22, and mixes with the original steam on the Nth packing plate 21. N+1 Encounter, cooling liquid phase X N-1 When heated again, the original liquid phase N-1 The low boiling point hydrochloric acid solution in the solution is evaporated, and part of the vaporized low boiling point hydrochloric acid solution is mixed with the original steam. N+1 Formation of new vapor phase Y N Rising, original steam phase Y N+1 The impurity solution with medium and high boiling points is partially condensed, and the partially condensed impurity solution with boiling points is mixed with the original solution. N-1 Formation of new liquid phase X N In the primary distillation tower 3, the low boiling point of hydrochloric acid and the high boiling point of the doping solution are used to separate the original liquid phase X N-1 Partial vaporization, original vapor phase Y N+1 By partial condensation, hydrochloric acid is purified step by step, and the doping solution is separated step by step. After the distillation process, the new vapor phase Y N The purity of hydrochloric acid in the vapor phase is greater than that of the original N+1 Purity of hydrochloric acid in the new liquid phase X N The hydrochloric acid concentration in the original liquid phase is less than N-1 The concentration of hydrochloric acid in the solution increases with the light component and decreases with the heavy component. The new liquid phase X N The concentration of hydrochloric acid in the solution approaches 0, and the new vapor phase Y N The concentration of hydrochloric acid is close to 100%.

[0028] Triangular pad 19 pairs of cooling fresh gas phase Y N It plays the role of diverting, diverting part of the liquid phase to the primary distillation tower 3 for distillation and purification, and the new vapor phase Y N After liquefaction, it enters the communication pipe 7. The filter 8 on the communication pipe 7 filters the liquefied hydrochloric acid solution again to block impurities. The hydrochloric acid is heated by the secondary reboiler 5, and undergoes a second round of extraction in the secondary distillation tower 6, and then output to the absorption tower and other subsequent processing steps. The new liquid phase X is finally produced. NFlows to the bottom of the primary heat exchanger 9, flows into the heat exchange bag 12 through the waste liquid pipe 13 at the bottom, and the final new liquid phase X N Still at a certain temperature, it flows through the spiral baffle plate 15 in the heat exchange capsule 12 and is discharged through the waste pipe 14. In the heat exchange capsule 12, the new liquid phase X N The raw material is fully contacted and exchanged with the raw material feed pipe 11 to preheat the raw material, thereby saving the heat energy of the reboiler and achieving the effect of energy saving and environmental protection.

[0029] It will be apparent to those skilled in the art that the 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 the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. An electronic grade hydrochloric acid preparation device, characterized in that: The invention comprises a raw material pump (1), a primary distillation tower (3) and a secondary distillation tower (6), wherein a primary reboiler (2) is arranged at the bottom of the primary distillation tower (3), a secondary reboiler (5) is arranged at the bottom of the secondary distillation tower (6), a cooler (4) and a communication pipe (7) are connected between the primary distillation tower (3) and the secondary distillation tower (6), a feed pipe (11) and a steam pipe (20) are connected to the primary reboiler (2) and the secondary reboiler (5), the feed pipe (11) on the primary reboiler (2) is connected to the raw material pump (1), the feed pipe (11) on the secondary distillation tower (6) is connected to the communication pipe (7), a primary heat exchanger (9) and a secondary heat exchanger (10) are arranged at the bottom of the primary distillation tower (3) and the secondary distillation tower (6), respectively, and the two feed pipes (11) respectively penetrate the adjacent heat exchangers.

2. The electronic grade hydrochloric acid preparation device according to claim 1, characterized in that: The primary distillation tower (3) comprises a bottom tower barrel (24), a plurality of middle tower barrels (26) and a top tower barrel (25), wherein the plurality of middle tower barrels (26) are connected between the bottom tower barrel (24) and the top tower barrel (25), and the bottom tower barrel (24), the middle tower barrel (26) and the top tower barrel (25) are connected via flanges (23) and bolts, and sealing rings are provided between the flanges (23).

3. An electronic grade hydrochloric acid preparation device according to claim 2, characterized in that: An air inlet is provided at the bottom of the bottom tower barrel (24), a waste liquid hole is provided on one side of the bottom of the bottom tower barrel (24), the air inlet is connected to the first-stage reboiler (2) via a steam pipe (20), the waste liquid hole is connected to the first-stage heat exchanger (9) via a waste liquid pipe (13), an air outlet is provided at the top of the top tower barrel (25), an air outlet pipe (16) is connected to the air outlet, and a reflux hole is provided on one side of the top of the top tower barrel (25).

4. The electronic grade hydrochloric acid preparation device according to claim 3, characterized in that: A plurality of groups of packing components are evenly arranged in the bottom tower tube (24), the plurality of middle tower tubes (26) and the top tower tube (25), each group of the packing components comprising a packing plate (21) and a plurality of dripping needles (22), the packing plate (21) being in the shape of an inverted bowl, a through hole being provided in the middle of the packing plate (21), a plurality of annular capillary ring grooves being provided at the top of the packing plate (21), a gap being provided between the packing plate (21) and the wall of the tower tube, and the packing plate (21) being mounted on the wall of the tube via a bracket.

5. The electronic grade hydrochloric acid preparation device according to claim 4, characterized in that: A plurality of the dripping needles (22) are evenly distributed in a ring shape on the wall of the tower, a plurality of the dripping needles (22) are arc-shaped, and a plurality of the dripping needles (22) are located above the packing plate (21). The structure and internal arrangement of the secondary distillation tower (6) are the same as the structure and internal structure of the primary distillation tower (3).

6. The electronic grade hydrochloric acid preparation device according to claim 3, characterized in that: A water-cooled circulation pipe (18) is arranged inside the cooler (4), and two through holes are provided on a side of the cooler (4) close to the primary distillation tower (3), the two through holes are respectively located on the upper and lower sides of the water-cooled circulation pipe (18), the through hole located at the upper side is connected to the air outlet pipe (16), and the through hole located at the lower side is connected to a reflux pipe (17), and the reflux pipe (17) is connected to the reflux hole of the primary distillation tower (3).

7. The device for preparing electronic grade hydrochloric acid according to claim 6, characterized in that: A triangular pad (19) is further provided inside the cooler (4), wherein the short hypotenuse of the triangular pad (19) is located on a side close to the primary distillation tower (3), and the long hypotenuse of the triangular pad (19) is located on a side close to the secondary distillation tower (6). A liquid outlet is provided at the bottom of the cooler (4) on a side away from the primary distillation tower (3), wherein the liquid outlet is connected to a communication pipe (7), wherein a plurality of filters (8) are provided in the middle of the communication pipe (7), and the gas outlet pipe (16) of the secondary distillation tower (6) is also connected to the cooler (4). The installation method of the cooler (4) on the secondary distillation tower (6) is the same as the installation method of the primary distillation tower (3).

8. The electronic grade hydrochloric acid preparation device according to claim 3, characterized in that: The primary heat exchanger (9) comprises a heat exchange capsule (12), a waste pipe (14) and a spiral baffle (15), wherein the spiral baffle (15) is located inside the heat exchange capsule (12), the feed pipe (11) connected to the primary reboiler (2) passes through the heat exchange capsule (12), the spiral baffle (15) is sealedly connected to the tube wall of the feed pipe (11) and the inside of the heat exchange capsule (12), the waste liquid pipe (13) at the bottom of the primary distillation tower (3) is connected to the heat exchange capsule (12), and the waste pipe (14) is connected to a side of the heat exchange capsule (12) away from the waste liquid pipe (13). The structure and installation method of the secondary heat exchanger (10) are the same as those of the primary heat exchanger (9).

9. A method for preparing electronic grade hydrochloric acid using the device for preparing electronic grade hydrochloric acid according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: S1: the hydrochloric acid raw material is transported to a primary reboiler (2) through a feed pipe (11) by using the raw material pump (1); the primary reboiler (2) is indirectly heated by steam, and the generated vapor phase hydrochloric acid is transported to a primary distillation tower (3) through the steam pipe (20); S2: The first-stage distillation tower (3) contains a packing layer inside, and the particles in the steam are intercepted after passing through the packing layer; S3: The rectified hydrochloric acid vapor is cooled by the cooler (4), and the liquefied hydrochloric acid liquid phase is transported to the secondary reboiler (5) through the connecting pipe (7). The secondary reboiler (5) is indirectly heated by steam, and the generated vapor phase hydrochloric acid is transported to the secondary distillation tower (6) through the steam pipe (20); S4: The secondary distillation tower (6) contains a packing layer inside, and the particulate matter in the hydrochloric acid vapor is intercepted after passing through the packing layer. The hydrochloric acid vapor of the secondary distillation is cooled by the cooler (4) and then transported to the subsequent absorption tower treatment process.

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