A staged cleaning device and method for silicon materials

Abstract

This invention discloses a staged cleaning device and method for silicon materials, relating to the field of silicon material cleaning technology. The device includes a housing extending along the workpiece conveying direction, divided into multiple independent processing stations along its length. At least three stations—a water washing station, an acid washing station, and a mixed acid cleaning station—are sequentially arranged along the workpiece flow direction, with an independent liquid storage tank below each station. A lead screw slide module is installed at the top of the device's operating chamber, connected to a base plate. The base plate is driven by a first cylinder to raise and lower a primary movable plate. The primary movable plate, through a sprocket and chain assembly, drives a secondary movable plate to achieve secondary raising and lowering. The secondary movable plate is adaptable to lateral displacement, and its bottom is equipped with a clamping mechanism for holding the cleaning frame. This invention can replace manual labor in completing multi-stage cleaning of silicon materials, improving the automation level of the equipment, avoiding the drawbacks of manual cleaning, and the accompanying cleaning method can significantly improve the cleaning quality of silicon material products.

Description

Technical Field

[0001] This invention relates to the field of silicon material cleaning technology, specifically to a staged silicon material cleaning device and cleaning method. Background Technology

[0002] In the silicon material processing and production process, the cleaning process is a key step in ensuring the cleanliness of the silicon surface and removing impurities and oxide layers. The quality of cleaning directly affects the product yield of subsequent processes and the performance of the final device. Currently, the industry generally uses chemical immersion to clean silicon materials, gradually removing various contaminants adhering to the silicon surface by immersing it in different types of cleaning solutions in sequence.

[0003] Current silicon material cleaning processes primarily rely on manual operation. Operators hold a basket containing the silicon material and immerse it entirely in a cleaning solution. The soaking sequence is hydrofluoric acid, a mixed acid solution (a mixture of nitric acid and hydrofluoric acid), and finally, water. After each step is completed for a specified duration, the material is transferred to the next cleaning solution tank. Once all soaking is complete, the material proceeds to the next processing stage. The entire soaking process is manually controlled by the operators, who typically rely on their experience to determine the soaking time. This reliance on subjective judgment easily leads to insufficient soaking time, resulting in inadequate corrosion and decontamination reactions on the silicon surface, ultimately affecting product quality. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a staged cleaning device for silicon materials. This device can replace manual cleaning, improve the automation level of the equipment, and overcome the drawbacks of manual cleaning. The combination of this device and the cleaning method significantly improves product quality.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A staged cleaning device for silicon materials includes a housing, a liquid storage tank, a screw slide module, a base plate, a primary movable plate, a first cylinder, a secondary movable plate, a secondary stroke plate, connecting parts, and a clamping mechanism. The housing is a cabinet structure extending along the workpiece conveying direction. The center of the front of the housing is recessed inward to form a device operating cavity extending along the length of the housing. The interior of the housing is divided into multiple independent processing stations along the length direction by vertical partitions, including at least a water washing station, an acid washing station, and a mixed acid cleaning station in sequence along the workpiece flow direction. An independent liquid storage tank is provided below each station in the device operating cavity. A screw slide module is installed on the top of the device operating cavity. The sliding parts of the screw slide module are fixedly connected to the base plate. A first cylinder is mounted on the base plate; a primary movable plate is slidably disposed below the base plate; the primary movable plate is fixedly connected to the telescopic end of the first cylinder; a second stroke plate is fixedly inserted into the surface of the primary movable plate; sprockets are rotatably disposed on both sides of the secondary stroke plate; the sprockets are driven by a chain; a through hole is opened in the middle of the primary movable plate and the base plate; a secondary movable plate is movably disposed in the vertical direction within the through hole; a connector is fixed on the chain; a support is disposed on the side of the secondary movable plate corresponding to the connector; the support and the connector are connected by a sliding rod; the secondary movable plate moves up and down driven by the chain, and can also move laterally along the body of the sliding rod; a clamping mechanism is installed at the bottom of the secondary movable plate, and the clamping mechanism clamps the cleaning frame.

[0006] Preferably, a second cylinder is fixedly installed on the outer side of the secondary movable plate; the telescopic end of the second cylinder is fixedly connected to the back of the support plate guide; the end of the support plate guide facing the secondary movable plate has an angular structure; a gap is reserved between the secondary movable plates for the support plate guide to enter; when the second cylinder extends to its maximum stroke, the angular structure of the support plate guide enters the gap, forcing the secondary movable plate to be opened.

[0007] Preferably, a support plate is fixed at the bottom of the base plate corresponding to the outer side of the secondary movable plate; a reset rod is movably inserted into the support plate; a baffle is fixed at the end of the reset rod; a reset spring is sleeved on the rod body of the reset rod; the reset spring is located between the support plate and the baffle; a ball is movably provided at the end of the reset rod, and the ball contacts the surface of the secondary movable plate.

[0008] Preferably, the clamping mechanism includes: a clamping head and a lifting rod; the clamping head is fixed to the bottom of the secondary movable plate; the lifting rod is fixedly inserted through the clamping head; the length of the lifting rod is greater than the length of the cleaning frame; the cleaning frame has strip grooves on both sides; the cleaning frame has an entry notch in the middle of the corresponding strip groove; after the lifting rod enters the notch, when the support plate guide forces the secondary movable plate to open, the lifting rod moves outward and is tightened to the maximum width of the strip groove.

[0009] Preferably, the base plate and the sliding component of the lead screw slide module are fixedly connected by a connecting plate; a guide rod is vertically fixed on the surface of the first-stage movable plate; a guide hole is opened on the base plate corresponding to the position of the guide rod; and a column is fixed on the bottom surface of the base plate.

[0010] Preferably, a feeding conveyor roller and a discharging conveyor roller are respectively installed inside both ends of the box; the conveying height of the feeding conveyor roller and the discharging conveyor roller is the same as the surface height of the liquid storage tank.

[0011] Preferably, the back of the equipment operating chamber is provided with a wall panel; air inlets are provided on the wall panels corresponding to the pickling station and the mixed acid cleaning station; each station has an independent chamber on the back of the wall panel; the top of the independent chamber of the pickling station and the mixed acid cleaning station is connected to the air outlet pipe; the air outlet pipe is connected to the air inlet of the fan; a carrying tank is provided in the independent chamber of the pickling station and the mixed acid cleaning station; the bottom of the carrying tank is connected to the waste liquid main pipe; a spray pipe is provided above the carrying tank; and a spray nozzle is provided on the spray pipe.

[0012] A cleaning method for a staged cleaning device for silicon materials, comprising the following steps: S1. Process Parameter Presetting and Cleaning Solution Preparation: The pre-washing station, hydrofluoric acid washing station, mixed acid cleaning station, and final washing station are arranged sequentially along the silicon material conveying direction, with each station having its own independent storage tank; the equipment operating parameters are preset; pure water is introduced into the storage tanks of the pre-washing and final washing stations; an aqueous solution with a hydrofluoric acid to water volume ratio of 1:57 to 1:80 is prepared for the hydrofluoric acid washing station, with an initial addition of 5 to 7 liters of hydrofluoric acid every 8-hour operating cycle; a mixed acid solution with a hydrofluoric acid to nitric acid volume ratio of 1:8 to 1:15 is prepared for the mixed acid cleaning station. S2, Feeding and Positioning: The feeding conveyor rollers horizontally transport the cleaning frame carrying silicon material to the designated picking point at the feeding end of the box, completing the positioning to be picked up. The silicon material loading capacity of a single frame is matched with the cycle capacity. S3. Clamping and Picking: The lead screw slide module drives the base plate and the clamping mechanism at the bottom to move horizontally to directly above the picking point. The first cylinder drives the first-stage movable plate to descend to the picking height. The clamping mechanism is engaged with the side of the cleaning frame by the lifting frame rod and is tightened and locked. Then the first-stage movable plate rises and resets to the transfer height, completing the gripping and fixing of the cleaning frame. S4. Multi-station continuous cleaning with a 420-second production cycle: A continuous production mode employing multiple stations processing in parallel and sequentially advancing; within a single production cycle, each of the four stations—pre-washing, hydrofluoric acid washing, mixed acid washing, and final washing—contains a cleaning frame, and each station synchronously and in parallel performs its corresponding process. The first cylinder drives the first-stage movable plate to descend vertically to the preset first-stage stroke position, so that the cleaning frame stops above the liquid surface of the corresponding storage tank. At this time, it is in the first-stage lifting state. Then, the second-stage lifting motor drives the second-stage movable plate to descend precisely in the vertical direction through the sprocket and chain mechanism, so that the cleaning frame continues to descend and is completely immersed in the cleaning liquid in the storage tank. At this time, it switches to the second-stage lifting state and completes the soaking and cleaning according to the preset time of each station. After the soaking time is completed, the secondary movable plate rises and resets to the primary stroke position, the cleaning frame rises back above the liquid surface, and returns to the primary lifting state. In this state, it remains stationary for a preset time to drain, removing the residual liquid trapped between the silicon material and the surface of the cleaning frame. After the draining time is completed, the first-level movable plate rises and resets to the transfer height; the cleaning frames in all stations move forward one station at a time along the silicon material conveying direction: the cleaning frames that have completed the final water washing process are transferred to the discharge end, the cleaning frames that have completed the mixed acid washing process are transferred to the final water washing station, the cleaning frames that have completed the hydrofluoric acid pickling process are transferred to the mixed acid washing station, and the cleaning frames that have completed the pre-water washing process are transferred to the hydrofluoric acid pickling station; at the same time, a new frame of silicon material to be cleaned is added to the pre-water washing station at the feeding end, so that each station always has material in the processing state and there is no idle waiting period; During the production process, the silicon material processing volume is controlled to be 2 tons per 8-hour cycle. The acid consumption is controlled at a ratio of 1 liter of hydrofluoric acid per 290 kg of silicon material processed. The hydrofluoric acid consumption includes two parts: silicon material entrainment consumption and alkaline neutralization consumption. All waste cleaning liquids used at each workstation are collected into the waste liquid main pipe through independent pipelines. The hydrofluoric acid pickling solution and mixed acid pickling solution are replaced as a whole every 8 hours. S5. Acid Mist Negative Pressure Absorption: The negative pressure suction system is activated throughout the operation of the hydrofluoric acid pickling station and the mixed acid cleaning station. The face velocity at the station opening is controlled at 0.4-0.6 m / s to extract the hydrofluoric acid mist and nitric acid mist generated in the station. The extracted acid mist is dissolved and absorbed by pure water spraying. The pure water spraying flow rate is controlled at 8-12 L / min. The acid-containing wastewater generated by the spraying absorption is simultaneously discharged into the waste liquid main pipe. S6. Material Output and Waste Liquid Reuse: After all cleaning processes are completed, the screw slide module moves the cleaning frame to the discharge end of the box, and the clamping mechanism releases the cleaning frame to the discharge conveyor roller for output; all waste cleaning liquid and acid mist spray absorption liquid generated at all stations are collected in the waste liquid tank through the waste liquid main pipe, and an alkaline neutralizing agent is added to the waste liquid tank to adjust the pH to 6.5-8.5. After precision filtration and activated carbon adsorption treatment, it is reused to the pre-washing station, and the amount of recycled water is controlled to account for 40%-60% of the total water consumption.

[0013] Beneficial effects of this invention: 1. Employing a multi-stage lifting structure combining a single-stage large-stroke lifting mechanism with a two-stage precision lifting mechanism, the system balances workpiece conveying efficiency with soaking accuracy. Combined with a side-support clamping mechanism, it ensures secure gripping and locking, smooth unlocking and resetting, and stable operation of the cleaning frame loading and unloading, as well as multi-station transfer. 2. Utilizing a multi-station sequential, synchronous, and parallel continuous production mode, each station simultaneously executes its corresponding cleaning process, eliminating idle waiting periods associated with sequential processing. This results in high equipment uptime and adaptability to the mass production needs of large-scale silicon material cleaning. 3. Each station is independently separated and equipped with its own independent liquid storage tank, ensuring stable cleaning quality. The acid pickling station is equipped with a spray system, where acid mist is dissolved in water for recovery. Waste liquid is centrally treated and can be reused, reducing water consumption and waste liquid discharge, while also meeting production safety and clean production requirements. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the external structure of the housing of the present invention.

[0016] Figure 2 This is a schematic diagram of the equipment operating cavity structure of the housing of the present invention.

[0017] Figure 3 This is a schematic diagram of the back structure of the housing of the present invention.

[0018] Figure 4 This is a schematic diagram of the internal structure of the housing of the present invention.

[0019] Figure 5 This is a schematic cross-sectional view of the side of the housing of the present invention.

[0020] Figure 6 This is a schematic diagram of the connection relationship of the lead screw slide module of the present invention.

[0021] Figure 7 This is a schematic diagram of the bottom connection relationship of the base plate of the present invention.

[0022] Figure 8 This is a schematic diagram of the clamping state of the cleaning frame according to the present invention.

[0023] Figure 9 This is a schematic diagram of the two-stage lifting and lowering state of the present invention.

[0024] Figure 10 This is a schematic diagram of the connection relationship of the box reset top rod of the present invention.

[0025] In the diagram, 1 is the housing, 1.1 is the equipment operating chamber, 1.2 is the vertical partition, 2 is the liquid storage tank, 3 is the lead screw slide module, 3.1 is the sliding component, 4 is the base plate, 4.1 is the guide hole, 4.2 is the column, 5 is the first-stage movable plate, 6 is the first cylinder, 7 is the second-stage movable plate, 7.1 is the support, 8 is the second-stage stroke plate, 9 is the connecting component, 10 is the clamping mechanism, 11 is the sprocket, 12 is the chain, 13 is the second-stage lifting motor, 14 is the slide bar, 15 is the cleaning frame, 15.1 is the strip groove, and 15 is the notch. .2, Second cylinder 16, Support plate guide 17, Angle structure 17.1, Clamping head 18, Lifting frame rod 19, Support plate 20, Reset top rod 21, Baffle 22, Reset spring 23, Ball bearing 24, Connecting plate 25, Guide rod 26, Feed conveyor roller 27, Discharge conveyor roller 28, Wall panel 29, Air inlet 29.1, Independent chamber 30, Air outlet pipe 31, Spray nozzle 32, Bearing tank 33, Waste liquid main pipe 34, Spray pipe 35. Detailed Implementation

[0026] like Figure 1 , 2 As shown in Figures 5 and 6, the silicon material staged cleaning equipment mainly includes a housing 1, a liquid storage tank 2, a lead screw slide module 3, a base plate 4, a primary movable plate 5, a first cylinder 6, a secondary movable plate 7, a secondary stroke plate 8, connecting parts 9, and a clamping mechanism 10. The housing 1 is a long, horizontal cabinet structure extending along the workpiece conveying direction. The center of the front of the housing 1 is recessed inward to form an equipment operating cavity 1.1 extending along the length of the housing 1. The interior of the housing 1 is divided into multiple independent processing stations along the length direction by vertical partitions 1.2. A pre-washing station, a hydrofluoric acid pickling station, a mixed acid cleaning station, and a final washing station are arranged sequentially along the workpiece flow direction. An independent liquid storage tank 2 is set below the equipment operating cavity 1.1 corresponding to each station. The top of the equipment operating cavity 1.1 is equipped with a lead screw slide module 3 along its length. The sliding part 3.1 of the lead screw slide module 3 is fixedly connected to the base plate 4 through the connecting plate 25. The length of the connecting plate 25 is greater than the length of the first cylinder 6, so as to reserve sufficient installation and operation space between the base plate 4 and the sliding part 3.1. The lead screw slide module 3 is driven by a motor, and the motor can be a stepper motor.

[0027] like Figure 6-10As shown, a first cylinder 6 is installed on the base plate 4, and a first-stage movable plate 5 is slidably arranged below the base plate 4. The surface of the first-stage movable plate 5 is fixedly connected to the telescopic end of the first cylinder 6. A guide rod 26 is vertically fixed to the surface of the first-stage movable plate 5, and a guide hole 4.1 is opened on the base plate 4 corresponding to the position of the guide rod 26. The guide rod 26 passes through the guide hole 4.1 to provide vertical guidance for the first-stage lifting action and avoid swaying during operation. A column 4.2 is fixed to the bottom surface of the base plate 4. The column 4.2 can limit the maximum stroke of the first-stage movable plate 5. The equipment operating space is reserved between the base plate 4 and the first-stage movable plate 5 to prevent the components on the first-stage movable plate 5 from directly colliding with the bottom of the base plate 4 when the plate moves upward. A secondary travel plate 8 is fixedly inserted into the surface of the primary movable plate 5. Sprockets 11 are rotatably mounted on both sides of the secondary travel plate 8, and the two sprockets 11 are connected by a chain 12. One of the sprockets 11 is connected to the drive end of the secondary lifting motor 13. The secondary lifting motor 13 precisely controls the rotation angle, achieving high-precision adjustment of the secondary lifting mechanism. To ensure accuracy, the secondary lifting motor 13 uses a stepper motor. Through holes are respectively opened in the middle of the primary movable plate 5 and the base plate 4, and a secondary movable plate 7 is movably mounted vertically within these through holes. A connecting piece 9 is fixed on the chain 12. A support 7.1 is provided on one side of the secondary movable plate 7 corresponding to the connecting piece 9. The support 7.1 and the connecting piece 9 are connected by a sliding rod 14, allowing the secondary movable plate 7 to move laterally along the sliding rod 14 while moving up and down with the chain 12, providing lateral displacement margin for the clamping and opening action. A clamping mechanism 10 is installed at the bottom of the secondary movable plate 7 to clamp the cleaning frame 15 carrying the silicon material. The clamping mechanism 10 includes a clamping head 18, a lifting rod 19, a second cylinder 16, a support plate guide 17, a return spring 23, and a return top rod 21. The clamping head 18 is fixed to the bottom of the secondary movable plate 7, and the lifting rod 19 is fixed through the clamping head 18. The length of the lifting rod 19 is greater than the length of the cleaning frame 15. The cleaning frame 15 has strip grooves 15.1 on both sides. The cleaning frame 15 has a notch 15.2 in the middle of the strip grooves 15.1 for the lifting rod 19 to enter. After the lifting rod 19 enters the strip groove 15.1 through the notch 15.2, the support plate guide 17 forces the secondary movable plate 7 to open outward, simultaneously driving the lifting rod 19 to move outward and tighten to the maximum width position of the strip groove 15.1, thus achieving a firm lock on the cleaning frame 15.

[0028] like Figure 6-10As shown, a second cylinder 16 is fixedly installed on the outer side of the secondary movable plate 7. The telescopic end of the second cylinder 16 is fixedly connected to the back of the support plate guide 17. The end of the support plate guide 17 facing the secondary movable plate 7 has an angled structure 17.1. A gap is reserved between the two sets of secondary movable plates 7 for the support plate guide 17 to enter. This gap is naturally formed by the width difference of the bottom clamping head 18: the width of the clamping head 18 is greater than the width of the secondary movable plate 7, so that the secondary movable plates 7 cannot be completely fitted when they move in opposite directions, forming a gap that facilitates the insertion of the support plate guide 17. When the second cylinder 16 extends to its maximum stroke, the angled structure 17.1 of the support plate guide 17 enters the gap, forcing the two sets of secondary movable plates 7 to open outward.

[0029] like Figure 6-10 As shown, a support plate 20 is fixed at the bottom of the base plate 4, corresponding to the outer position of the secondary movable plate 7. A reset rod 21 is movably inserted on the support plate 20. A baffle 22 is fixed at the end of the reset rod 21. A reset spring 23 is sleeved on the body of the reset rod 21, and the reset spring 23 is located between the support plate 20 and the baffle 22. A ball bearing 24 is movably installed at the end of the reset rod 21. The ball bearing 24 rolls in contact with the surface of the secondary movable plate 7. When the support plate guide 17 retracts with the second cylinder 16, the reset spring 23 releases its elastic force to push the reset rod 21 inward, causing the secondary movable plate 7 to move and reset in the opposite direction, reducing the distance between the two lifting frame rods 19, so that the lifting frame rods 19 can be moved out from the notch 15.2, completing the separation of the cleaning frame 15 from the equipment.

[0030] like Figure 3-5 As shown, a feeding conveyor roller 27 and a discharging conveyor roller 28 are respectively installed inside both ends of the housing 1. The conveying height of the feeding conveyor roller 27 and the discharging conveyor roller 28 is consistent with the surface height of the liquid storage tank 2, ensuring a smooth and stable handover process for the cleaning frame 15. A wall panel 29 is set on the back of the equipment operating chamber 1.1. Air inlets 29.1 are opened on the wall panels 29 corresponding to the hydrofluoric acid pickling station and the mixed acid cleaning station. An independent chamber 30 is set on the back of the wall panel 29 corresponding to each station. The top of the independent chamber 30 of the pickling station and the mixed acid cleaning station is connected to the air outlet pipe 31. The air outlet pipe 31 is connected to the air inlet of the fan to form a complete negative pressure suction passage. A carrier tank 33 is installed in the independent chamber 30 of the pickling station and the mixed acid cleaning station. The bottom of the carrier tank 33 is connected to the waste liquid main pipe 34. A spray pipe 35 is installed above the carrier tank 33. Spray nozzles 32 are arranged on the spray pipe 35, which can spray pure water to dissolve and absorb the acid mist. The wastewater generated by absorption flows into the carrier tank 33 and then into the waste liquid main pipe 34 for unified treatment.

[0031] The silicon material staged cleaning method based on the above equipment operates according to the following process: First, process parameters are preset and cleaning solution is prepared. Each station is arranged sequentially along the silicon material conveying direction and a corresponding independent liquid storage tank 2 is set. The equipment operating parameters are preset, and the corresponding cleaning solution is introduced or prepared to different stations. Then, feeding and positioning are performed. The feeding conveyor roller 27 horizontally conveys the cleaning frame 15 carrying silicon material to the designated picking point at the feeding end of the box 1, completing the positioning to be gripped. The silicon material loading capacity of a single frame is matched with the cycle capacity. After that, the clamping and picking action is performed. The lead screw slide module 3 drives the base plate 4 and the bottom clamping mechanism 10 to move horizontally to directly above the picking point. The first cylinder 6 drives the first-stage movable plate 5 to descend to the picking height. The clamping mechanism 10 is engaged with the side of the cleaning frame 15 through the lifting rod 19 and is tightened and locked. Then, the first-stage movable plate 5 rises and resets to the transfer height, completing the gripping and fixing of the cleaning frame 15.

[0032] After entering the multi-station continuous cleaning stage, a multi-station parallel processing and sequential step-by-step continuous production mode is adopted. Within a single production cycle, all stations carry the cleaning frame 15, and each station synchronously and in parallel performs its corresponding process. The first cylinder 6 first drives the primary movable plate 5 vertically downward to the preset primary stroke position, causing the cleaning frame 15 to stop above the liquid surface of the corresponding storage tank 2, in the primary lifting state. Subsequently, the secondary lifting motor 13 drives the secondary movable plate 7 to precisely descend vertically through the sprocket 11 and chain 12 mechanism, causing the cleaning frame 15 to continue descending and be completely immersed in the cleaning liquid in the storage tank 2, switching to the secondary lifting state, and completing the soaking and cleaning according to the preset time for each station. After the soaking time ends, the secondary movable plate 7 rises back to the primary stroke position, and the cleaning frame 15 rises back above the liquid surface, returning to the primary lifting state. In this state, it remains stationary for the preset time to drain, removing residual liquid from the silicon material and the surface of the cleaning frame 15. After the draining time ends, the first-level movable plate 5 rises and resets to the transfer height. The cleaning frames 15 in all stations move forward one station in sequence along the silicon material conveying direction. At the same time, a new frame of silicon material to be cleaned is added to the pre-washing station at the feeding end, so that each station always has material in the processing state and there is no idle waiting period.

[0033] During operation, the hydrofluoric acid pickling station and the mixed acid cleaning station operate with a negative pressure suction system throughout. The hydrofluoric acid mist and nitric acid mist generated in the suction station are dissolved and absorbed by pure water spray. The acid-containing wastewater generated by the spray absorption is simultaneously discharged into the waste liquid main pipe 34. After all cleaning processes are completed, the screw slide module 3 moves the cleaning frame 15 to the discharge end of the box 1. The clamping mechanism 10 releases the cleaning frame 15 to the discharge conveyor roller 28 for output. The waste cleaning liquid and acid mist spray absorption liquid generated by all stations are collected and treated in a unified manner through the waste liquid main pipe 34 for reuse.

[0034] In this embodiment, the production cycle time is set to 420s, including 15s for horizontal transfer between single workstations, 10s for a single first-level lifting action, and 5s for a single second-level lifting action. The process durations for each workstation are set as follows: 180s for immersion cleaning and 30s for draining above the liquid surface at the pre-washing station; 360s for immersion cleaning and 45s for draining above the liquid surface at the hydrofluoric acid pickling station; 360s for immersion cleaning and 45s for draining above the liquid surface at the mixed acid cleaning station; and 180s for immersion cleaning and 30s for draining above the liquid surface at the final rinsing station.

[0035] During the cleaning solution preparation stage, pure water is introduced into the storage tank 2 of the pre-wash and final wash stations; an aqueous solution with a volume ratio of hydrofluoric acid to water of 1:68 is prepared for the hydrofluoric acid pickling station, with an initial addition of 6 liters of hydrofluoric acid every 8-hour operating cycle; and a mixed acid solution with a volume ratio of hydrofluoric acid to nitric acid of 1:12 is prepared for the mixed acid cleaning station.

[0036] In actual operation, the cleaning frame 15 carrying silicon material is conveyed to the picking point via the feeding conveyor roller 27. The screw slide module 3 drives the clamping mechanism 10 to move horizontally for 15 seconds to reach directly above the picking point. The first cylinder 6 drives the first-stage movable plate 5 to descend to the picking height in 10 seconds. After the lifting rod 19 aligns with the notch 15.2 on the side of the cleaning frame 15 and enters the strip groove 15.1, the second cylinder 16 extends to drive the guide plate 17 to open the second-stage movable plate 7, so that the lifting rod 19 is tightened and locked. Subsequently, the first-stage movable plate 5 rises to the transfer height in 10 seconds and is horizontally transferred to directly above the pre-washing station in 15 seconds.

[0037] At the pre-wash station, the primary movable plate 5 descends to the primary stroke position in 10 seconds, and the cleaning frame 15 remains above the liquid surface. Then, the secondary lifting mechanism lowers the cleaning frame 15 into the pure water in 5 seconds, maintaining immersion for 180 seconds. After immersion, the secondary movable plate 7 rises back to the primary stroke position in 5 seconds, and the cleaning frame 15 remains above the liquid surface to drain for 30 seconds. After draining, the primary movable plate 5 rises to the transfer height in 10 seconds and is horizontally transferred to the hydrofluoric acid pickling station in 15 seconds. The hydrofluoric acid pickling station and the mixed acid cleaning station repeat the above lifting and lowering actions, completing 360 seconds of immersion and 45 seconds of draining respectively. The final wash station completes 180 seconds of immersion and 30 seconds of draining. After each 420-second production cycle, the cleaning frames 15 in all stations move forward one station simultaneously. The cleaning frames 15 that have completed the final water washing process are transferred to the output end, and the feeding end simultaneously replenishes a new frame of silicon material to be cleaned to the pre-water washing station, thus achieving continuous parallel production across all stations.

[0038] During production, the silicon material processing volume is controlled at 2 tons per 8-hour cycle. Acid consumption is managed at a ratio of 1 liter of hydrofluoric acid per 290 kg of silicon material processed. The hydrofluoric acid pickling solution and mixed acid pickling solution are completely replaced every 8 hours. The negative pressure suction system controls the face velocity at the workstation opening to 0.5 m / s, and the pure water spray flow rate is set to 10 L / min for efficient absorption of acid mist. All waste liquids are collected, and an alkaline neutralizing agent is added to adjust the pH to 7.0–8.0. After precision filtration and activated carbon adsorption treatment, the waste liquid is reused at the pre-washing station, with recycled water accounting for 50% of the total water consumption.

[0039] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A staged cleaning device for silicon material, comprising a housing, a liquid storage tank, a lead screw slide module, a base plate, a primary movable plate, a first cylinder, a secondary movable plate, a secondary stroke plate, connecting parts, and a clamping mechanism; The housing is a cabinet structure extending along the workpiece conveying direction. The center of the front of the housing is recessed inward to form an equipment operating cavity extending along the length of the housing. The interior of the housing is divided into multiple independent processing stations along the length direction by vertical partitions, including at least a water washing station, an acid washing station, and a mixed acid cleaning station in sequence along the workpiece flow direction. Each station has an independent liquid storage tank at the bottom of the equipment operating cavity. A lead screw slide module is installed on the top of the equipment operating cavity. The sliding component of the lead screw slide module is fixedly connected to the base plate. A first cylinder is mounted on the base plate; a primary movable plate is slidably disposed below the base plate; the primary movable plate is fixedly connected to the telescopic end of the first cylinder; a second stroke plate is fixedly inserted into the surface of the primary movable plate; sprockets are rotatably disposed on both sides of the secondary stroke plate; the sprockets are driven by a chain; a through hole is opened in the middle of the primary movable plate and the base plate; a secondary movable plate is movably disposed in the vertical direction within the through hole; a connector is fixed on the chain; a support is disposed on the side of the secondary movable plate corresponding to the connector; the support and the connector are connected by a sliding rod; the secondary movable plate moves up and down driven by the chain, and can also move laterally along the body of the sliding rod; a clamping mechanism is installed at the bottom of the secondary movable plate, and the clamping mechanism clamps the cleaning frame.

2. The silicon material staged cleaning equipment according to claim 1, characterized in that: A second cylinder is fixedly installed on the outer side of the secondary movable plate; the telescopic end of the second cylinder is fixedly connected to the back of the support plate guide; the end of the support plate guide facing the secondary movable plate has an angular structure; a gap is reserved between the secondary movable plates for the support plate guide to enter; when the second cylinder extends to its maximum stroke, the angular structure of the support plate guide enters the gap, forcing the secondary movable plate to be opened.

3. The silicon material staged cleaning equipment according to claim 1, characterized in that: A support plate is fixed at the bottom of the base plate corresponding to the outer side of the secondary movable plate; a reset rod is movably inserted on the support plate; a baffle is fixed at the end of the reset rod; a reset spring is sleeved on the rod body of the reset rod; the reset spring is located between the support plate and the baffle; a ball is movably provided at the end of the reset rod, and the ball contacts the surface of the secondary movable plate.

4. The silicon material staged cleaning equipment according to claim 3, characterized in that: The clamping mechanism includes: a clamping head and a lifting rod; the clamping head is fixed to the bottom of the secondary movable plate; the lifting rod is fixedly inserted through the clamping head; the length of the lifting rod is greater than the length of the cleaning frame; the cleaning frame has strip grooves on both sides; the cleaning frame has an entry notch in the middle of the corresponding strip groove; after the lifting rod enters the notch, when the support plate guide forces the secondary movable plate to open, the lifting rod moves outward and is tightened to the maximum width of the strip groove.

5. The silicon material staged cleaning equipment according to claim 1, characterized in that: The base plate and the sliding component of the lead screw slide module are fixedly connected by a connecting plate; a guide rod is vertically fixed on the surface of the first-stage movable plate; a guide hole is opened on the base plate corresponding to the position of the guide rod; and a column is fixed on the bottom surface of the base plate.

6. The silicon material staged cleaning equipment according to claim 1, characterized in that: The two ends of the box are respectively equipped with a feeding conveyor roller and a discharging conveyor roller; the conveying height of the feeding conveyor roller and the discharging conveyor roller is the same as the surface height of the liquid storage tank.

7. The silicon material staged cleaning equipment according to claim 1, characterized in that: The back of the equipment's operating chamber is provided with a wall panel; air inlets are provided on the wall panels corresponding to the pickling and mixed acid cleaning stations; each station has an independent chamber on the back of its wall panel; the top of the independent chambers of the pickling and mixed acid cleaning stations is connected to an air outlet pipe; the air outlet pipe is connected to the air inlet of a blower; a carrying tank is provided in the independent chambers of the pickling and mixed acid cleaning stations; the bottom of the carrying tank is connected to a waste liquid main pipe; a spray pipe is provided above the carrying tank; and a spray nozzle is provided on the spray pipe.

8. A cleaning method based on the silicon material staged cleaning equipment according to claim 7, comprising the following steps: S1. Process Parameter Presetting and Cleaning Solution Preparation: The pre-washing station, hydrofluoric acid washing station, mixed acid cleaning station, and final washing station are arranged sequentially along the silicon material conveying direction, with each station having its own independent storage tank; the equipment operating parameters are preset; pure water is introduced into the storage tanks of the pre-washing and final washing stations; an aqueous solution with a hydrofluoric acid to water volume ratio of 1:57 to 1:80 is prepared for the hydrofluoric acid washing station, with an initial addition of 5 to 7 liters of hydrofluoric acid every 8-hour operating cycle; a mixed acid solution with a hydrofluoric acid to nitric acid volume ratio of 1:8 to 1:15 is prepared for the mixed acid cleaning station. S2, Feeding and Positioning: The feeding conveyor rollers horizontally transport the cleaning frame carrying silicon material to the designated picking point at the feeding end of the box, completing the positioning to be picked up. The silicon material loading capacity of a single frame is matched with the cycle capacity. S3. Clamping and Picking: The lead screw slide module drives the base plate and the clamping mechanism at the bottom to move horizontally to directly above the picking point. The first cylinder drives the first-stage movable plate to descend to the picking height. The clamping mechanism is engaged with the side of the cleaning frame by the lifting frame rod and is tightened and locked. Then the first-stage movable plate rises and resets to the transfer height, completing the gripping and fixing of the cleaning frame. S4. Multi-station continuous cleaning with a 420-second production cycle: A continuous production mode employing multiple stations processing in parallel and sequentially advancing; within a single production cycle, each of the four stations—pre-washing, hydrofluoric acid washing, mixed acid washing, and final washing—contains a cleaning frame, and each station synchronously and in parallel performs its corresponding process. The first cylinder drives the first-stage movable plate to descend vertically to the preset first-stage stroke position, so that the cleaning frame stops above the liquid surface of the corresponding storage tank. At this time, it is in the first-stage lifting state. Then, the second-stage lifting motor drives the second-stage movable plate to descend precisely in the vertical direction through the sprocket and chain mechanism, so that the cleaning frame continues to descend and is completely immersed in the cleaning liquid in the storage tank. At this time, it switches to the second-stage lifting state and completes the soaking and cleaning according to the preset time of each station. After the soaking time is completed, the secondary movable plate rises and resets to the primary stroke position, the cleaning frame rises back above the liquid surface, and returns to the primary lifting state. In this state, it remains stationary for a preset time to drain, removing the residual liquid trapped between the silicon material and the surface of the cleaning frame. After the draining time is completed, the first-level movable plate rises and resets to the transfer height; the cleaning frames in all stations move forward one station at a time along the silicon material conveying direction: the cleaning frames that have completed the final water washing process are transferred to the discharge end, the cleaning frames that have completed the mixed acid washing process are transferred to the final water washing station, the cleaning frames that have completed the hydrofluoric acid pickling process are transferred to the mixed acid washing station, and the cleaning frames that have completed the pre-water washing process are transferred to the hydrofluoric acid pickling station; at the same time, a new frame of silicon material to be cleaned is added to the pre-water washing station at the feeding end, so that each station always has material in the processing state and there is no idle waiting period; During the production process, the silicon material processing volume is controlled to be 2 tons per 8-hour cycle. The acid consumption is controlled at a ratio of 1 liter of hydrofluoric acid per 290 kg of silicon material processed. The hydrofluoric acid consumption includes two parts: silicon material entrainment consumption and alkaline neutralization consumption. All waste cleaning liquids used at each workstation are collected into the waste liquid main pipe through independent pipelines. The hydrofluoric acid pickling solution and mixed acid pickling solution are replaced as a whole every 8 hours. S5. Acid Mist Negative Pressure Absorption: The negative pressure suction system is activated throughout the operation of the hydrofluoric acid pickling station and the mixed acid cleaning station. The face velocity at the station opening is controlled at 0.4-0.6 m / s to extract the hydrofluoric acid mist and nitric acid mist generated in the station. The extracted acid mist is dissolved and absorbed by pure water spraying. The pure water spraying flow rate is controlled at 8-12 L / min. The acid-containing wastewater generated by the spraying absorption is simultaneously discharged into the waste liquid main pipe. S6. Material Output and Waste Liquid Reuse: After all cleaning processes are completed, the screw slide module moves the cleaning frame to the discharge end of the box, and the clamping mechanism releases the cleaning frame to the discharge conveyor roller for output; all waste cleaning liquid and acid mist spray absorption liquid generated at all stations are collected in the waste liquid tank through the waste liquid main pipe, and an alkaline neutralizing agent is added to the waste liquid tank to adjust the pH to 6.5-8.

5. After precision filtration and activated carbon adsorption treatment, it is reused to the pre-washing station, and the amount of recycled water is controlled to account for 40%-60% of the total water consumption.

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