A cooling crystallization kettle for electroplating grade nickel sulfate

Abstract

The utility model discloses a cooling crystallization kettle for electroplating grade nickel sulfate, the efficient cooling crystallization kettle structure design novel of utility model's electroplating grade nickel sulfate is good to nickel sulfate cooling crystallization working condition adaptability. Through circulating water cloth water main pipe, circulating water backwater main pipe, heat exchange column pipe combination screw belt type self -cooling stirring solves the low heat exchange efficiency of cooling process, and the problem of uneven heat exchange. Through the mode of screw belt type self -cooling stirring device promotes heat exchange replaces stirring high -speed rotation to promote heat exchange simultaneously, and then greatly reduces the stirring speed, avoids secondary nucleation phenomenon, solves the problem of too many fine crystals.

Description

Technical Field

[0001] This utility model belongs to the field of electroplating grade nickel sulfate crystallization, and particularly relates to a cooling crystallization kettle for electroplating grade nickel sulfate. Background Technology

[0002] Electroplating-grade nickel sulfate is widely used in the automotive, electronics, aerospace, and precision instrument industries due to its high purity, good solubility, stable chemical properties, and ability to significantly improve the corrosion resistance and hardness of the substrate. The industrial production process of electroplating-grade nickel sulfate mainly involves dissolution, extraction, degreasing, evaporation, crystallization, centrifugation, drying, sieving, and packaging. During crystallization, the traditional crystallization vessel uses a jacketed heat exchanger and relies on stirring to promote heat exchange, resulting in low fluid heat exchange efficiency, uneven heat exchange, and a large number of fine crystals. Simultaneously, excessively high stirring speeds lead to secondary nucleation, forming fine crystals and further affecting the crystal size range. Better crystal size uniformity results in higher coating quality and adhesion during electroplating. Therefore, solving the problems of fine crystal formation and low particle size uniformity during crystallization is crucial for further improving the quality of the electroplating process and meeting the stringent requirements of downstream customers. Utility Model Content

[0003] (1) Technical problem to be solved: The traditional crystallization vessel adopts a jacketed heat exchange structure and relies on stirring and rotation to promote heat exchange. However, the heat exchange efficiency is low and the heat exchange is uneven during the crystallization process of electroplating grade nickel sulfate. This utility model proposes a cooling crystallization vessel for electroplating grade nickel sulfate to solve this problem.

[0004] (2) The technical solution adopted by this utility model is as follows: A cooling crystallization vessel for electroplating grade nickel sulfate includes a crystallization vessel with a jacket inside. The jacket connects a cooling water inlet section and a cooling water outlet section. Inside the jacket are a circulating water distribution main pipe, a circulating water return main pipe, and multiple heat exchange tubes connecting the circulating water distribution main pipe and the circulating water return main pipe. The circulating water distribution main pipe is connected to a circulating water inlet section, and the circulating water return main pipe is connected to a circulating water outlet section. A spiral-type self-cooling stirring device is installed inside the crystallization vessel, which includes a stirring shaft and stirring blades. The upper and lower parts of the stirring shaft are hollow structures, and the stirring blades connect the upper and lower hollow structures of the stirring shaft. Both ends of the stirring shaft extend out of the crystallization vessel and are rotatably connected to it. A driving device is installed at the top of the crystallization vessel, which is connected to the stirring shaft to drive the stirring shaft to rotate. The driving device includes a geared motor, and the output shaft of the geared motor is connected to the stirring shaft through a transmission assembly. A feed inlet is provided at the top of the crystallization vessel, and a discharge outlet is provided at the bottom of the crystallization vessel.

[0005] A further technical solution is that the stirring blade includes multiple No. 1 support blades connected to the upper part of the stirring shaft, No. 2 support blades connected to the lower part of the stirring shaft with a number matching the number of No. 1 support blades, and a spiral blade connected between the No. 1 support blades and the No. 2 support blades. The No. 1 support blades, the spiral blades, and the No. 2 support blades are all hollow structures, and the interior of the upper part of the stirring shaft, the No. 1 support blades, the spiral blades, and the lower part of the stirring shaft are sequentially connected.

[0006] A further technical solution is that the transmission assembly includes a driving pulley fixed on the output shaft of the geared motor and a driven pulley fixed on the stirring shaft, with the driving pulley and the driven pulley connected by a transmission belt.

[0007] A further technical solution involves installing multiple support frames below the main circulating water distribution pipe inside the jacket, with the support frames fixed to the inner wall of the jacket.

[0008] A further technical solution is that a material-gathering blade is provided below the stirring shaft inside the crystallization vessel.

[0009] (3) Due to the adoption of the above technical solution, the beneficial effects of this utility model are: 1. This utility model features a novel high-efficiency cooling crystallization kettle for electroplating-grade nickel sulfate, exhibiting excellent adaptability to nickel sulfate cooling and crystallization conditions. It addresses the issues of low heat exchange efficiency and uneven heat exchange during the cooling process by combining a circulating water distribution main pipe, a circulating water return main pipe, and heat exchange tubes with a ribbon-type self-cooling agitator. The ribbon-type self-cooling agitator promotes heat exchange while simultaneously replacing high-speed stirring, significantly reducing the stirring speed, avoiding secondary nucleation, and resolving the problem of excessive fine crystals.

[0010] 2. This invention is applicable to the crystallization of electroplating-grade nickel sulfate. It features efficient and uniform heat exchange in the nickel sulfate solution, effectively reducing stirring speed, avoiding secondary nucleation, forming fine crystals, and significantly improving the uniformity of crystal size. The innovative design of the high-efficiency cooling crystallization vessel for electroplating-grade nickel sulfate technically improves the structure and working principle of traditional crystallization vessels, effectively solving the problems of low fluid heat exchange efficiency, uneven heat exchange, a large number of fine crystals, and low particle size uniformity. This further meets the requirements of uniform nickel sulfate crystal size for coating quality and adhesion during the electroplating process. Attached Figure Description

[0011] Figure 1 This is a cross-sectional view of the overall structure of this utility model; Figure 2 This is a top view of the present invention; Figure 3 This is a schematic diagram of the circulating water distribution main pipe, circulating water return main pipe, and heat exchange tube structure of the present invention; Figure 4This is a schematic diagram of the structure of the spiral self-cooling stirring device described in this utility model; Figure 5 This is a cross-sectional schematic diagram of the ribbon-type self-cooling stirring device described in this utility model; Figure 6 This is a schematic diagram of a high-speed rotary shut-off valve. Detailed Implementation

[0012] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments.

[0013] like Figures 1-6 As shown.

[0014] Example 1: A cooling crystallization vessel for electroplating grade nickel sulfate, comprising a crystallization vessel, wherein a jacket 19 is provided inside the crystallization vessel, the jacket 19 is connected to a cooling water inlet section 14 and a cooling water outlet section 16, the jacket 19 is provided with a circulating water distribution main pipe 4, a circulating water return main pipe 21, and a plurality of heat exchange tubes 3 connecting the circulating water distribution main pipe 4 and the circulating water return main pipe 21, the circulating water distribution main pipe 4 is connected to a circulating water inlet section 6, the circulating water return main pipe 21 is connected to a circulating water outlet section 20, and a spiral self-cooling stirring device 15 is provided inside the crystallization vessel, which includes a stirring shaft 151 and a... The stirring blades and the upper and lower parts of the stirring shaft 151 are hollow structures. The stirring blades connect the upper and lower hollow structures of the stirring shaft 151. Both ends of the stirring shaft 151 extend out of the crystallization vessel and are rotatably connected to it. A driving device is provided at the top of the crystallization vessel. The driving device is connected to the stirring shaft 151 to drive the stirring shaft 151 to rotate. The driving device includes a geared motor 11. The output shaft of the geared motor 11 is connected to the stirring shaft 151 through a transmission assembly. A feed inlet 22 is provided at the top of the crystallization vessel, and a discharge outlet 18 is provided at the bottom of the crystallization vessel. The geared motor 11 is provided at the top of the crystallization vessel.

[0015] The problem of introducing a large amount of cooling water into the spiral self-cooling stirring device 15 is solved by using a "high-speed rotary shut-off valve". The stirring blades include multiple #1 support blades 152 connected to the upper part of the stirring shaft 151, and #2 support blades 154, matching the number of #1 support blades 152, connected to the lower part of the stirring shaft. Spiral blades 153 connect the #1 support blades 152 and #2 support blades 154. The #1 support blades 152, spiral blades 153, and #2 support blades 154 are all hollow structures, and the upper part of the stirring shaft 151, the #1 support blades 152, the spiral blades 153, and the lower part of the stirring shaft 151 are sequentially connected internally. The transmission assembly includes a drive pulley 12 fixed to the output shaft of the reduction motor 11 and a driven pulley 9 fixed to the stirring shaft 151. The drive pulley 12 and the driven pulley 9 are connected by a transmission belt. Both ends of the stirring shaft 151 are connected to the water supply and return pipelines via conventional rotary joints or rotating shut-off valves 10 and 17 for circulating water inlet and outlet. The rotating shut-off valves 10 and 17 are both "a type of high-speed rotary shut-off valve" (authorization announcement number: CN222229484U), designed to introduce a large amount of circulating water into the stirring shaft 151 and the rotating ribbon-type self-cooling stirring device 15. Their operating principle is not detailed here. The crystallizer jacket 19 is formed by the inner wall 1 and outer wall 2 of the crystallizer. The stirring shaft 151 and the crystallizer body are connected by a conventional bearing and mechanical seal with sealing function. The heat exchange tubes 3 are three straight tubes with a diameter of 32mm, arranged in an array around the central axis of the crystallizer. A material-collecting impeller 155 is installed below the stirring shaft 151 inside the crystallizer. The top of the crystallization vessel is a vessel cover 5, and the feed inlet 22 is located on the vessel cover 5. An observation hole 23 is provided on the top of the vessel cover 5. A reinforcing I-beam 7, a supporting steel plate 8, and a geared motor bracket 13 are provided on the top of the vessel cover 5 for mounting the geared motor 11.

[0016] Working process: The evaporated nickel sulfate solution enters the crystallization vessel through inlet 22. Cooling water enters the jacket 19 through cooling water inlet section 14. Circulating water enters the circulating water distribution main pipe 4 through circulating water inlet section 6, then enters the 240 heat exchange tubes 3, then enters the circulating water return main pipe 21 through the heat exchange tubes 3, and finally exits through the circulating water outlet section 20. The circulating water in the heat exchange tubes 3 performs large-area heat exchange and cooling of the cooling water in the jacket 19, and then the cooling water passes through the inner wall 1 of the crystallization vessel to perform heat exchange and cooling of the nickel sulfate solution. At this time, the heat exchange area of ​​the crystallization vessel is optimized from the heat exchange of the inner wall of the jacket 19 of the traditional crystallization vessel to the heat exchange of the 240 tubes, increasing the heat exchange area by about 320% and significantly improving the heat exchange efficiency. Simultaneously, circulating water enters the upper hollow part of the stirring shaft 151 of the spiral self-cooling stirring device 15 through the circulating water inlet rotary shut-off valve 10, then enters the No. 1 support blade 152 through the upper hollow part of the stirring shaft 151, then enters the spiral blade 153 through the No. 1 support blade 152, then enters the No. 2 support blade 154 through the spiral blade 153, and finally collects at the lower hollow part of the stirring shaft 151, and is discharged through the circulating water outlet shut-off valve. The bottom of the stirring shaft 151 is equipped with a material-gathering paddle 155 for gathering and discharging material at the bottom of the crystallization vessel, thus achieving heat exchange and cooling of the stirring body. The heat exchange and cooling of the stirring body optimizes the traditional crystallization vessel heat exchange area, which is concentrated on one side of the vessel body, to a heat exchange area that occurs simultaneously within the stirring rotation trajectory and on the outer perimeter of the vessel body. This achieves uniformity in the heat exchange process and prevents local overheating or overcooling. Traditional crystallization stirring operates at a higher speed, also aiming to accelerate heat conduction in the solution, making the solution temperature more uniform, preventing local overheating or overcooling, and ensuring consistent particle size during the crystallization process. Therefore, the structural design of the stirring body heat exchange can effectively replace the promoting effect of high stirring speed on the heat conduction of the solution. In other words, the stirring body heat exchange can avoid the influence of excessively high stirring speed on secondary nucleation of crystals or crystal shearing and breakage, and further ensure the consistency of crystal particle size distribution.

[0017] Example 2: Multiple support frames 24 are installed below the circulating water distribution main pipe 4 inside the jacket 19. The support frames 24 are fixed to the inner wall of the jacket 19 to realize the installation of the circulating water distribution main pipe 4. The circulating water inlet section 6 passes through the top of the vessel cover 5 and is welded to it (the vessel cover 5 has reserved installation holes for the circulating water inlet section 6). The circulating water outlet section 20 passes through the outer wall 2 of the crystallization vessel and is welded to it (the outer wall 2 of the crystallization vessel has reserved installation holes for the circulating water outlet section 20).

[0018] The above are merely preferred embodiments of this utility model.

Claims

1. A cooling crystallization vessel for electroplating grade nickel sulfate, comprising a crystallization vessel, characterized in that, The crystallizer is equipped with a jacket (19), which connects the cooling water inlet section (14) and the cooling water outlet section (16). Inside the jacket (19) are a circulating water distribution main pipe (4), a circulating water return main pipe (21), and multiple heat exchange tubes (3) connecting the circulating water distribution main pipe (4) and the circulating water return main pipe (21). The circulating water distribution main pipe (4) is connected to the circulating water inlet section (6), and the circulating water return main pipe (21) is connected to the circulating water outlet section (20). The crystallizer is equipped with a spiral self-cooling stirring device (15), which includes a stirring shaft (151) and stirring blades. The upper and lower parts of the stirring shaft (151) are hollow structures, and the stirring blades connect the upper and lower hollow structures of the stirring shaft (151). The upper and lower ends of the stirring shaft (151) extend out of the crystallizer and are rotatably connected to it. The top of the crystallizer is equipped with a driving device, which is connected to the stirring shaft (151) to drive the stirring shaft (151) to rotate.

2. The cooling crystallization kettle for electroplating grade nickel sulfate according to claim 1, characterized in that, The stirring blades include multiple No. 1 support blades (152) connected to the upper part of the stirring shaft (151), and No. 2 support blades (154) connected to the lower part of the stirring shaft (151) in number matching the No. 1 support blades (152). A spiral blade (153) is connected between the No. 1 support blades (152) and the No. 2 support blades (154). The No. 1 support blades (152), the spiral blades (153), and the No. 2 support blades (154) are all hollow structures, and the interior of the upper part of the stirring shaft (151), the No. 1 support blades (152), the spiral blades (153), and the lower part of the stirring shaft (151) are sequentially connected.

3. The cooling crystallization kettle for electroplating grade nickel sulfate according to claim 1, characterized in that, The drive unit includes a geared motor (11), the output shaft of the geared motor (11) is connected to the stirring shaft (151) through a transmission assembly, the top of the crystallizer is provided with a feed port (22), and the bottom of the crystallizer is provided with a discharge port (18).

4. The cooling crystallization kettle for electroplating grade nickel sulfate according to claim 2, characterized in that, The transmission assembly includes a drive pulley (12) fixed on the output shaft of the geared motor (11) and a driven pulley (9) fixed on the stirring shaft (151). The drive pulley (12) and the driven pulley (9) are connected by a transmission belt.

5. The cooling crystallization kettle for electroplating grade nickel sulfate according to claim 1, characterized in that, Multiple support frames (24) are installed inside the jacket (19) below the circulating water distribution main pipe (4), and the support frames (24) are fixed to the inner wall of the jacket (19).

6. The cooling crystallization kettle for electroplating grade nickel sulfate according to claim 1, characterized in that, The crystallizer is equipped with a material-gathering blade (155) at the lower part of the stirring shaft (151).

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