Developing solution recycling system

Abstract

The utility model relates to a developing solution recycling system which comprises a developing tank, a delivery pump, a collecting tank, a nano bubble removing device, a transfer tank, a rotary membrane filtering device, a backwashing collecting tank and a high-speed centrifugal device, the nano bubble removing device is used for removing hydrophobic particles in the developing solution, the developing solution is conveyed into the rotating membrane filtering device from the transfer tank, the rotating membrane filtering device is used for separating suspension liquid containing high-concentration, high-viscosity and high-solid-content materials in the developing solution to the backwashing collecting tank, and the filtered developing solution is discharged and recycled. And conveying the suspension to a high-speed centrifugal device to separate solid film residues from liquid. According to the developing solution recycling system, the developing solution can be recycled in a full-automatic operation mode, a filter element is not needed for filtering, manpower and dangerous solid waste treatment cost are saved, and therefore the problem that the yield of PCBs is gradually reduced along with pollution of the developing solution is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor manufacturing, in particular to a developer circulation recovery system. Background Art

[0002] PCB is a functional electroplating, and its quality is directly related to the cleanliness of the chemical solution. The special functions of high-density, high-precision, multi-functional, and high-aspect-ratio multi-layer PCB products require clean chemical solution filtration to play a key role in quality. The chemical solution contains mechanical impurities, and these particles must be removed in time; the presence of organic resist coatings such as green oil, solder resist, inner and outer developer / photosensitive inks, the decomposition of additives (brighteners), and the precipitation of resist coating components will all contaminate the chemical solution, causing defects in the coating.

[0003] The filtering method that the industry has been using is filter elements and filter bags. For decades, the filtering technology has not been able to make a breakthrough. In the production process of PCB circuit boards, there are problems such as: incomplete development leads to short circuits and residual copper; frequent tank changes affect production efficiency; frequent maintenance of the medicine tank has high maintenance costs; 80% of the COD wastewater from the circuit board comes from film stripping and developer; frequent tank reversal and maintenance waste a lot of manpower and material resources. Utility Model Content

[0004] The main purpose of the utility model is to provide a developer recycling system to solve the above technical problems, thereby improving the problem that the PCB yield gradually decreases due to developer contamination.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A developer recycling system comprises a developer tank, a delivery pump, a collection tank, a nano bubble removal device, a transfer tank, a rotary membrane filter device, a backwash collection tank and a high-speed centrifugal device, wherein the developer tank stores the developer, the delivery pump delivers the developer that has completed the reaction to the collection tank, the developer is delivered from the collection tank to the nano bubble removal device, the nano bubble removal device removes hydrophobic particles in the developer, the delivery pump delivers the remaining developer to the transfer tank, the developer is delivered from the transfer tank to the rotary membrane filter device, the rotary membrane filter device separates a suspension containing high-concentration, high-viscosity and high-solid content materials in the developer to the backwash collection tank, discharges and recovers the developer after filtration, and delivers the suspension from the backwash collection tank to the high-speed centrifugal device, the high-speed centrifugal device separates solid membrane residue from liquid.

[0007] As a preferred technical solution, the high-speed centrifugal device includes a base plate, a cover, a differential, a drum mechanism and a screw conveying mechanism. The cover and the differential are fixed on the base plate, the drum mechanism is installed in the cover, the screw conveying mechanism is installed in the drum mechanism, and the differential is connected to the drum mechanism and the screw conveying mechanism respectively.

[0008] As a preferred technical solution, the drum mechanism includes a drum and a first motor, the first motor is installed at one end of the differential, and the first motor drives the drum to rotate.

[0009] As a preferred technical solution, the screw conveying mechanism includes a screw conveyor and a second motor, the second motor is installed at the other end of the differential, the screw conveyor is installed in the drum, and the second motor drives the screw conveyor to rotate.

[0010] As a preferred technical solution, the four corners of the lower end of the base plate are fixedly installed with supporting feet, and the lower ends of the four supporting feet are fixedly installed with shock absorbers.

[0011] As a preferred technical solution, the rotary membrane filtration device includes a rotary mechanism, a blower, a water inlet mechanism and a sewage discharge pipe, and the water inlet mechanism, the blower and the sewage discharge pipe are respectively connected to the rotary mechanism.

[0012] As a preferred technical solution, the water inlet mechanism includes a water inlet pump and a water inlet pipe, and the water inlet pump is connected to the rotating mechanism through the water inlet pipe.

[0013] As a preferred technical solution, the rotating mechanism includes a rotating speed changer, a rotating component, a filter barrel and a fixed seat, the filter barrel and the rotating speed changer are installed on the fixed seat, the rotating component is rotatably set in the filter barrel, and the rotating speed changer drives the rotating component to rotate.

[0014] As a preferred technical solution, the rotating assembly includes a filter membrane, a rotating shaft and a spacer block, and the filter membrane and the spacer block are alternately installed on the rotating shaft.

[0015] The beneficial effects of the utility model are as follows: the developer recycling system removes suspended matter in the developer by means of a nano bubble removal device, recovers the developer by means of a rotary membrane filter device, separates the suspended liquid, and finally separates the solid membrane residue by means of a high-speed centrifugal device. The developer can be recycled fully automatically without the need for filtering with a filter element, thus saving manpower and hazardous solid waste treatment costs, thereby improving the problem of a gradual decrease in PCB yield as the developer is contaminated. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a wireframe diagram of the developer recycling system involved in the utility model;

[0017] Figure 2 It is a structural schematic diagram of the rotary membrane filtration device involved in the utility model;

[0018] Figure 3 It is a cross-sectional view of the rotary membrane filtration device involved in the utility model;

[0019] Figure 4 It is a three-dimensional cross-sectional view of the filter membrane of the rotary membrane filtration device involved in the utility model;

[0020] Figure 5 It is a structural schematic diagram of the high-speed centrifugal device involved in the utility model. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0022] like Figure 1 As shown, a developer recycling system includes a developer tank 1, a delivery pump 2, a collection tank 3, a nano bubble removal device 4, a transfer tank 5, a rotary membrane filter device 6, a backwash collection tank 7 and a high-speed centrifuge device 8. The developer tank 1 stores the developer, and the developer can react with the photosensitive adhesive that is not exposed to ultraviolet rays. The exposed PCB is placed in the developer tank. During the development process, the photosensitive adhesive of the unexposed part will be dissolved, while the exposed part will be retained. After the development is completed, the developer is mixed with other impurities, so it needs to be filtered and recycled. The delivery pump 2 delivers the developer that has completed the reaction to the collection tank 3, and the developer is delivered from the collection tank 3. To the nano bubble removal device 4, the nano bubble removal device 4 transports nano bubbles into the developer, and the suspended matter in the developer adheres to the bubble surface and floats, thereby separating from the developer to remove the hydrophobic particles in the developer. The delivery pump 2 transports the remaining developer to the transfer tank 5, and the developer is transported from the transfer tank 5 to the rotary membrane filter device 6. The rotary membrane filter device 6 separates the suspension containing high-concentration, high-viscosity and high-solid content materials in the developer to the backwash collection tank 7, discharges and recovers the developer after filtration, and transports the suspension from the backwash collection tank 7 to the high-speed centrifugal device 8, which separates the solid membrane residue from the liquid.

[0023] Please combine Figure 2-Figure 4As shown, the rotary membrane filtration device 6 includes a frame 61, and a rotating mechanism 62, a blower 64, a water inlet mechanism 63 and a drain pipe 65 arranged on the frame 61. The water inlet mechanism 63, the blower 64 and the drain pipe 65 are respectively connected to the rotating mechanism 62. The water inlet mechanism 63 transports the developer to the rotating mechanism 62. The rotating mechanism 62 rotates, and the blower 64 blows air into the rotating mechanism 62. The rotation, air and water mixed flushing separates the materials with high concentration, high viscosity and high solid content, and the clean developer is discharged. Then, backwashing is performed to form a suspension with the material. The drain pipe 65 transports the suspension to the backwashing collection tank 7. In addition, when the flushing method cannot meet the flushing requirements, the chemical washing function can be started for rapid recovery.

[0024] The water inlet mechanism 63 includes a water inlet pump 631 and a water inlet pipe 632. The water inlet pump 631 is connected to the rotating mechanism 62 through the water inlet pipe 632. The rotating mechanism 62 includes a rotating speed changer 621, a rotating assembly 624, a filter barrel 623 and a fixed seat 622. The fixed seat 622 is fixed on the frame 61. The filter barrel 623 and the rotating speed changer 621 are installed on the fixed seat 622. The rotating assembly 624 is rotatably arranged in the filter barrel 623. The rotating speed changer 621 drives the rotating assembly 624 to rotate. The rotating assembly 624 includes a filter membrane 627, a drain pipe 628, a rotating shaft 625 and a partition block 626. The filter membrane 627 and the partition block 626 are alternately installed on the rotating shaft 625. The drain pipe 628 is connected to the rotating shaft 625. The rotating shaft 625 is a hollow shaft. The filter membrane 627 includes a fixed hole 6273, a filter cake layer 6271 and a filter channel 6272. The filter cake layer 6271 is arranged on the outer surface of the filter channel 6272, the fixed hole 6273 is arranged in the middle of the filter cake layer 6271, and the rotating shaft 625 passes through the fixed hole 6273. The filter channel 6272 is connected to the rotating shaft 625. The filter cake layer 6271 can perform double-sided filtration, and the effective filtration area is increased within the equivalent volume, thereby improving the filtration efficiency and stability, and is easier to clean. The swirling flushing generates high shear force on the surface of the filter membrane 627 to form a swirling sweep flow. The shear force removes impurities in the filter cake layer 6271, forming an efficient cleaning of the surface of the filter membrane 627, while maintaining a large flux, which is suitable for the concentration and separation of materials containing high concentration, high viscosity and high solid content. The filter pore size of the filter layer 627 is ≥1500 mesh, so that the developer can enter the filter cake 6271, enter the rotating shaft 625 through the filter channel 6272, and then be discharged and recovered from the drain pipe 628. The filter membrane 627 does not require replacement costs, which greatly saves labor costs and hazardous solid waste treatment costs.

[0025] In this embodiment, the power of the water inlet pump 631 is 5.5 kW, the frequency is 50 Hz, and the independent test flow rate is 60-70 M 3 / H, the diameter of the water inlet pipe 632 is DN100, the diameter of the sewage pipe 65 is DN50, and the diameter of the drainage pipe 628 is DN80.

[0026] like Figure 5 As shown, the high-speed centrifugal device 8 includes a base plate 81, a cover shell 82, a differential 83, a drum mechanism 84 and a screw conveying mechanism 85. The cover shell 82 and the differential 83 are fixed on the base plate 81, the drum mechanism 84 is installed in the cover shell 82, and the screw conveying mechanism 85 is installed in the drum mechanism 84. The differential 83 is connected to the drum mechanism 84 and the screw conveying mechanism 85 respectively. The drum mechanism 84 rotates, and the screw conveying mechanism 85 rotates in the same direction as the drum mechanism 84, and the rotation speed is slightly lower than that of the drum mechanism 84. The differential 83 plays a role in changing the rotation speed of the drum mechanism 84 and the screw conveying mechanism 85.

[0027] The drum mechanism 84 includes a drum 841 and a first motor 842. The first motor 842 is installed at one end of the differential 83, and the first motor 842 drives the drum 841 to rotate. The screw conveying mechanism 85 includes a screw conveyor 851 and a second motor 852. The second motor 852 is installed at the other end of the differential 83. The screw conveyor 851 is installed in the drum 841. The screw conveyor 851 is provided with a hollow shaft. The second motor 852 drives the screw conveyor 851 to rotate. The suspension to be separated is fed into the inner cavity of the screw conveyor 851 through a feeding pipe. The first motor 842 and the second motor 852 are turned on to make the drum 841 and the screw conveyor 851 rotate at different speeds. The high-speed rotating drum 841 generates a strong centrifugal force to throw the solid phase particles with a density greater than that of the liquid phase onto the inner wall of the drum 841, so as to separate the suspension into solid and liquid. Support legs 811 are fixedly installed at the four corners of the lower end of the bottom plate 81, and shock absorbers 812 are fixedly installed at the lower ends of the four support legs 811 to reduce the vibration force generated during separation.

[0028] The above-described embodiments are only preferred examples of the present invention and are not intended to limit the scope of implementation of the present invention. Therefore, any equivalent changes or modifications made based on the structures, features and principles described in the patent application scope of the present invention should be included in the scope of the patent application of the present invention.

Claims

1. A developer recycling system, characterized in that: The invention comprises a developing tank, a delivery pump, a collecting tank, a nano bubble removal device, a transfer tank, a rotary membrane filter device, a backwashing collecting tank and a high-speed centrifugal device, wherein the developing tank stores a developer, the delivery pump delivers the developer that has completed the reaction to the collecting tank, the developer is delivered from the collecting tank to the nano bubble removal device, the nano bubble removal device removes hydrophobic particles in the developer, the delivery pump delivers the remaining developer to the transfer tank, the developer is delivered from the transfer tank to the rotary membrane filter device, the rotary membrane filter device separates a suspension containing high-concentration, high-viscosity and high-solid content materials in the developer to the backwashing collecting tank, discharges and recovers the developer after filtration, and delivers the suspension from the backwashing collecting tank to the high-speed centrifugal device, the high-speed centrifugal device separates solid membrane residue from liquid.

2. The developer recycling system according to claim 1, characterized in that: The high-speed centrifugal device comprises a bottom plate, a cover, a differential, a drum mechanism and a screw conveying mechanism. The cover and the differential are fixed on the bottom plate, the drum mechanism is installed in the cover, the screw conveying mechanism is installed in the drum mechanism, and the differential is connected to the drum mechanism and the screw conveying mechanism respectively.

3. The developer recycling system according to claim 2, characterized in that: The drum mechanism includes a drum and a first motor, wherein the first motor is installed at one end of the differential, and the first motor drives the drum to rotate.

4. The developer recycling system according to claim 3, characterized in that: The screw conveying mechanism includes a screw conveyor and a second motor, wherein the second motor is installed at the other end of the differential, the screw conveyor is installed in the rotating drum, and the second motor drives the screw conveyor to rotate.

5. The developer recycling system according to claim 4, characterized in that: The four corners of the lower end of the bottom plate are all fixedly installed with supporting feet, and the lower ends of the four supporting feet are all fixedly installed with shock absorbers.

6. The developer recycling system according to claim 5, characterized in that: The rotary membrane filtration device comprises a rotary mechanism, a blower, a water inlet mechanism and a sewage discharge pipe, wherein the water inlet mechanism, the blower and the sewage discharge pipe are respectively connected to the rotary mechanism.

7. The developer recycling system according to claim 6, characterized in that: The water inlet mechanism comprises a water inlet pump and a water inlet pipe, and the water inlet pump is connected with the rotating mechanism through the water inlet pipe.

8. The developer recycling system according to claim 7, characterized in that: The rotating mechanism includes a rotating speed changer, a rotating assembly, a filter barrel and a fixed seat. The filter barrel and the rotating speed changer are installed on the fixed seat. The rotating assembly is rotatably arranged in the filter barrel, and the rotating speed changer drives the rotating assembly to rotate.

9. The developer recycling system according to claim 8, characterized in that: The rotating assembly comprises a filter membrane, a rotating shaft and a spacer block, and the filter membrane and the spacer block are alternately installed on the rotating shaft.

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