Cleaning process based on distillation separation rinsing agent regeneration cycle system

Abstract

The invention discloses a cleaning process based on a distillation separation rinsing agent regeneration cycle system. The cleaning process comprises the steps of pretreatment of a workpiece in a plate, atomization cleaning, reagent isolation wind shearing, rinsing treatment, wind shearing after rinsing, hot air drying, workpiece out-of-plate, condensation and reuse of a cleaning agent and a rinsing agent, distillation treatment of uncondensed gas and graded flow division and reuse. Pure water cleaning is not needed in the whole process, reagent closed-loop circulation is achieved through condensation recycling and distillation purification, cross contamination is effectively blocked through reagent isolation wind shear, the purity of a regenerated reagent is guaranteed through distillation separation, wastewater-free discharge is achieved so that the environmental protection pressure and the treatment cost can be reduced, reagent consumption and resource waste are reduced, and batch production requirements are met; environmental protection and economical efficiency are both considered, and the cleaning quality of the precision workpiece can be stably guaranteed.

Description

Technical Field

[0001] This invention relates to the field of industrial precision cleaning technology, specifically to a cleaning process based on a distillation separation and rinsing agent regeneration and circulation system, which is particularly suitable for cleaning flux residues from precision workpieces such as flip chips, SIP advanced packaging modules, and mobile phone battery control boards. Background Technology

[0002] In the industrial cleaning process of precision workpieces, the rinsing step is crucial for removing residual cleaning agent from the workpiece surface, directly affecting the quality of subsequent encapsulation and curing. Currently, the industry commonly uses disposable rinsing agents or simple filtration followed by recycling, but this approach has significant drawbacks: In disposable solutions, the rinsing agent contains flux residue, metallic impurities, and other contaminants after use, making it unusable and requiring direct discharge. This not only wastes a large amount of resources but also generates substantial amounts of industrial wastewater, resulting in high environmental treatment costs. Simple filtration and recycling solutions can only remove some solid particles and cannot separate organic impurities such as flux residue dissolved in the rinsing agent. This leads to a rapid decline in the purity of the rinsing agent, causing secondary contamination of the workpiece surface after reuse and affecting cleaning accuracy.

[0003] While some existing technologies involve reagent distillation recovery, they are mostly applied to the recovery of single solvents and lack specific distillation separation designs for rinsing agents (often mixed solvent systems) in cleaning processes. This results in problems such as low separation efficiency, insufficient purity of regenerated reagents, and poor system compatibility with cleaning processes. Furthermore, existing distillation recovery systems and cleaning equipment are mostly designed as separate units, lacking a closed-loop linkage for the collection, transportation, regeneration, and reflux of rinsing agents. This leads to low regeneration efficiency, high energy consumption, and difficulty in meeting the needs of industrial-scale mass production.

[0004] Therefore, developing a cleaning process that is highly compatible with the cleaning process, can efficiently separate various contaminants in the rinsing agent, and can realize a closed-loop recycling of the rinsing agent has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a cleaning process based on a distillation separation and rinsing agent regeneration and circulation system, thereby solving at least one of the above-mentioned technical problems of the prior art.

[0006] This invention discloses a cleaning process based on a distillation separation and regeneration circulation system for the rinsing agent, comprising the following steps: Step A: Pre-processing of workpieces before boarding. Precision workpieces are boarded and pre-processed to remove surface dust and large impurities. Step B, atomized cleaning: Atomized cleaning agent is sprayed onto the surface of the workpiece after step A to dissolve and remove flux residue on the surface of the workpiece. Step C, reagent isolation air cutting: The workpiece after step B is treated with reagent isolation air cutting to blow away the residual cleaning agent droplets on the surface of the workpiece and prevent the cleaning agent from mixing into subsequent processes. Step D, rinsing treatment: Atomize and spray the regenerated rinsing agent onto the surface of the workpiece after step C to remove the residual cleaning agent on the surface of the workpiece, and collect the used rinsing agent containing impurities. Step E: Air cutting after rinsing. The workpiece treated in step D is air-cut to remove the regenerated rinsing agent droplets adhering to the surface of the workpiece. Step F, hot air drying: hot air is blown onto the workpiece after step E to completely evaporate the residual regeneration rinsing agent on the workpiece surface. Step G: Workpiece removal from the plate. The dried workpiece is removed from the plate and stored. Step H, cleaning agent condensation and reuse: the cleaning agent gas generated by the atomized cleaning in step B is introduced into the cleaning agent condensation and recovery unit, and after condensation treatment, liquid cleaning agent is obtained and returned to the cleaning process for reuse; Step I, rinsing agent condensation and reuse: The rinsing agent gas generated in step D is introduced into the rinsing agent condensation and recovery unit. After condensation, liquid rinsing agent is obtained and returned to the rinsing process for reuse. Step J: Distillation of uncondensed gas. The cleaning agent gas that was not completely condensed in step H and the rinsing agent gas that was not completely condensed in step I are introduced into the distillation equipment together, and the purification of the two reagents is achieved by fractional distillation separation. Step K involves graded diversion and reuse, where the cleaning agent and rinsing agent purified by distillation in step J are diverted to their respective cleaning agent storage tanks and rinsing agent storage tanks for reuse in the atomization cleaning of step B and the rinsing treatment of step D.

[0007] Furthermore, in step F, the waste heat generated by hot air drying is recovered and utilized through a heat exchange unit, with the waste heat temperature being 80-100℃. This waste heat is used to preheat the cleaning agent gas in step H and the rinsing agent gas in step I, resulting in a preheated gas temperature of 40-60℃, which is 15-30℃ lower than the boiling point of the corresponding reagents. The waste heat can also assist in the distillation heating in step J. This achieves resource utilization of waste heat during the drying process, reduces energy consumption for condensing and recovering the cleaning agent and rinsing agent gases, and simultaneously reduces energy consumption for distillation heating, thus improving the overall energy efficiency of the process. The preheated gas temperature precisely matches the condensation requirements, preventing premature vaporization of the reagents and ensuring efficient condensation recovery.

[0008] Furthermore, in step J, the fractional distillation is based on the difference in boiling points between the cleaning agent and the rinsing agent. The boiling point of the cleaning agent is ≥230℃, while the boiling point of the rinsing agent is 98-100℃. The operating pressure is atmospheric pressure, and the distillation temperature is controlled between 80-160℃. This utilizes the difference in boiling points to achieve precise fractional separation, avoiding reagent mixing during distillation and ensuring that the purity of the regenerated cleaning agent and rinsing agent meets the standards. The atmospheric pressure distillation design reduces the complexity and cost of equipment operation, and the distillation temperature range is adapted to the characteristics of the reagents, ensuring both separation effectiveness and preventing reagent decomposition.

[0009] Furthermore, in step B, the atomization cleaning stage employs at least three continuous processing units; in step D, the rinsing stage employs at least four continuous processing units. The workpiece sequentially passes through each processing unit to complete the corresponding process, and is replaced only when the reagent concentration reaches a set threshold. Through multi-unit gradient processing, the reagent is recycled "from dirty to clean," maintaining a stable reagent concentration in each processing unit, improving the uniformity of cleaning and rinsing; extending the reagent replacement cycle, reducing reagent waste and replacement costs, and avoiding the impact of reagent concentration fluctuations on cleaning quality.

[0010] Furthermore, in step D, the rinsing agent is circulated at a rate of 30-50 liters per hour. This rinsing agent consumption is far lower than that of traditional pure water rinsing (800-1200 liters / hour), significantly reducing reagent consumption and subsequent processing pressure. The low-volume design reduces the energy consumption and load of distillation and purification, further reducing production and operating costs, while also reducing environmental burden. The rinsing agent can be a commonly used non-aqueous rinsing agent in the industry.

[0011] Furthermore, in step J, the distillation equipment adopts an energy-saving heating method, namely air source heating or MVR heating. This replaces traditional heating rods, significantly reducing energy consumption in the distillation process and meeting energy conservation and environmental protection requirements. Air source and MVR heating methods are highly adaptable and can be flexibly adjusted according to production load, further optimizing the energy utilization efficiency of the process.

[0012] Furthermore, by adjusting the airflow through an electric butterfly valve and monitoring real-time data from an anemometer, the pressure balance of the atomized cleaning, rinsing, and isolation areas is dynamically maintained. This precisely addresses the unstable airflow conditions in customer factories, using dynamic pressure regulation to block the cross-flow of water mist between cleaning and rinsing agents, enhancing the anti-cross-liquid effect; reducing reagent evaporation losses, lowering VOC emissions to reduce their environmental impact, and ensuring the stability of process operation.

[0013] Furthermore, both the cleaning agent condensation and recovery unit and the rinsing agent condensation and recovery unit adopt a cross-coil structure. This extends the cooling path and residence time of the atomized reagent within the condensation unit, increasing the condensation recovery rate to ≥98% and reducing reagent waste. The cross-coil structure also enhances heat exchange efficiency, reduces energy consumption in the condensation process, and further improves the closed loop of reagent recycling.

[0014] Furthermore, in step H, the condensed and collected liquid cleaning agent is filtered to remove solid impurities before being returned to the cleaning process for reuse. This effectively removes solid impurities from the condensed cleaning agent, preventing impurities from clogging the atomizing components and ensuring the uniformity of atomized cleaning and the service life of the equipment; it also improves the purity of the recycled cleaning agent, avoiding the impact of residual impurities on the cleaning effect of precision workpieces.

[0015] Furthermore, in step I, the condensed and collected liquid rinsing agent is filtered to remove solid impurities and then returned to the rinsing process for reuse. Removing solid impurities from the rinsing agent ensures the cleanliness of the rinsing process, prevents impurities from adhering to the surface of precision workpieces and affecting product quality, extends the recycling cycle of the rinsing agent, reduces the frequency of reagent replacement due to impurity accumulation, and lowers production costs.

[0016] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: (1) No pure water is needed for cleaning throughout the process, achieving zero wastewater discharge, reducing environmental pollution and lowering wastewater treatment costs.

[0017] (2) Both cleaning agents and rinsing agents are recycled and reused through condensation and distillation purification, which reduces reagent consumption and lowers the cost of production consumables.

[0018] (3) The reagent isolation air cutting step effectively prevents the cleaning agent from mixing with subsequent processes, avoids cross-contamination of reagents, and ensures the cleaning effect of the rinsing process.

[0019] (4) Uncondensed gas is separated and purified by staged distillation to ensure the purity of the regenerated reagent and ensure the stability of the cleaning quality of precision workpieces.

[0020] (5) The process steps are consistent and adaptable to the needs of mass production, improving the cleaning efficiency of precision workpieces.

[0021] (6) The entire process forms a closed-loop reagent cycle, reducing resource waste and taking into account both environmental protection and economy. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.

[0023] Figure 1 This is a flowchart of the cleaning process in the embodiment. Detailed Implementation

[0024] This invention discloses a specific implementation of a cleaning process based on a distillation separation and regeneration circulation system for the rinsing agent. Please see [link / description]. Figure 1 This invention discloses a cleaning process based on a distillation separation and rinsing agent regeneration and circulation system. Its core is to solve the problems of excessive wastewater discharge, high reagent consumption, and unstable cleaning quality in traditional processes by using reagent circulation and graded separation without the participation of pure water. The specific implementation process is as follows.

[0025] 101. First, perform step A, workpiece pretreatment. Precision workpieces such as flip chips and SIP modules are smoothly placed into the board using an anti-static conveyor. At the same time, high-pressure airflow combined with flexible brush cleaning is used to pretreat the workpiece surface, thoroughly removing surface dust and large impurities. This prevents impurities from scratching the workpiece surface or affecting the contact effect between cleaning agent and flux residue during subsequent cleaning, laying a clean foundation for subsequent processes. In a preferred embodiment, the workpiece pre-processing in step A includes a first workpiece pre-processing and a second workpiece pre-processing. The first workpiece pre-processing involves pre-processing the precision workpiece before it enters the board and simultaneously pre-processing the workpiece surface, performing a first removal of surface dust and large impurities. The second workpiece pre-processing involves capturing an image of the workpiece surface after the first pre-processing to analyze the remaining amount of large impurities and / or surface sediment. Based on the analysis results, a judgment is made on whether to perform atomized cleaning. If there are still large impurities and / or surface sediment exceeding the threshold, a second removal of surface dust and large impurities is performed. If there are no large impurities or sediment, or if there are large impurities or sediment within the threshold range, step B is directly executed. The purpose of this operation is to prevent damage to the workpiece in subsequent cleaning or rinsing stages due to incomplete removal of large impurities or sediment during the pre-processing stage, as is the case in the prior art.

[0026] 102. After pretreatment, the process proceeds to step B, atomization cleaning. Upon entering the cleaning zone, cleaning agent is evenly sprayed onto the workpiece surface treated in step A using an array of atomizing nozzles. The cleaning agent quickly dissolves and removes flux residue from the workpiece surface. In step B, the atomization cleaning stage employs at least three continuous processing units, each independently configured. Each independently configured processing unit has a cleaning fluid recovery unit at its bottom, and each recovery unit is equipped with an impurity filter. The workpiece sequentially passes through each processing unit to complete the cleaning operation. The cleaning agent within each unit circulates in a "dirtiest to clean" order, only being replaced when the reagent concentration reaches a set threshold. This multi-unit gradient circulation design avoids excessive accumulation of impurities in certain areas, extends reagent lifespan, and ensures the stability of the cleaning effect.

[0027] 103. After step B is completed, step C, reagent isolation air cutting, is performed. A high-pressure air knife is used to air-cut the surface of the workpiece treated in step B, removing residual cleaning agent droplets and preventing cross-contamination of the cleaning agent into subsequent rinsing processes. Considering the potential instability of the customer's factory's exhaust volume, this step uses an electric butterfly valve to adjust the exhaust volume, and, in conjunction with real-time monitoring data from an anemometer, dynamically maintains the pressure balance of the atomized cleaning, rinsing, and isolation areas. Even if the exhaust volume fluctuates, it effectively prevents water mist cross-contamination, ensuring process stability. This design solves the problem of reagent cross-contamination caused by unstable exhaust in traditional processes.

[0028] 104. After step C is completed, the process proceeds to step D, rinsing. A regenerated rinsing agent is atomized and sprayed onto the surface of the workpiece treated in step C to thoroughly remove any residual cleaning agent. Simultaneously, the used rinsing agent containing impurities is collected in the collection tank below. In a preferred embodiment, step D employs at least four independently configured continuous rinsing units. The workpiece sequentially passes through each rinsing unit to complete the rinsing process. Each rinsing unit is equipped with a rinsing liquid collection tank, and each collection tank has a filter device. The circulating usage of the rinsing agent is strictly controlled at 30-50 liters per hour, which is far lower than the 800-1200 liters / hour used in traditional pure water rinsing, significantly reducing energy consumption and environmental treatment costs. The multi-unit rinsing design is adopted to achieve efficient utilization of the rinsing agent through gradient purification, ensuring that no cleaning agent residue remains on the surface of the workpiece after the final rinsing unit. This also reduces past significant waste of the rinsing agent, enabling long-term recycling of the rinsing agent, reducing costs, and minimizing pollution.

[0029] In a preferred embodiment, a liquid-prevention isolation zone is provided between the cleaning zone and the rinsing zone to physically prevent liquid cross-contamination. This isolation zone is equipped with baffles inclined towards the cleaning and rinsing zones respectively, used to physically isolate the cleaning and rinsing solutions in their respective areas. The baffles are spaced apart and have drainage channels to guide the liquefied cleaning and rinsing solutions to their respective cleaning and rinsing storage tanks. This maximizes the prevention of workpiece contamination caused by cross-contamination between cleaning and rinsing agents, building upon the existing separate processing zones.

[0030] 105. After rinsing, perform step E, post-rinsing air cutting. Use a low-pressure, high-volume air cutting device to air-cut the workpiece treated in step D, blowing away any residual regenerated rinsing agent droplets adhering to the workpiece surface. This ensures no obvious droplet residue remains on the workpiece surface, creating conditions for the subsequent hot air drying process. The air cutting intensity in this step should be controlled to avoid damaging the workpiece surface while ensuring effective droplet removal, preventing residual droplets from affecting drying efficiency or causing water stains on the workpiece surface.

[0031] 106. Subsequently, step F, hot air drying, is performed. Hot air is blown onto the workpiece treated in step E to completely evaporate the residual regenerated rinsing agent on the workpiece surface. The hot air temperature is controlled at 80-100℃. This temperature range ensures rapid evaporation of the rinsing agent without damaging the precision workpiece. In step F, the waste heat generated by hot air drying is recovered and reused through a heat exchange unit. The waste heat temperature is stabilized at 80-100℃, and the heat exchange efficiency of the heat exchange unit is not less than 85%. The recovered waste heat is used to preheat the cleaning agent gas in subsequent step H and the rinsing agent gas in step I. After preheating, the gas temperature is controlled at 40-60℃, which is 15-30℃ lower than the boiling point of the corresponding reagent. This improves the efficiency of subsequent condensation and recovery and avoids premature vaporization of the reagent, thus preventing waste. On the other hand, it can also assist in the distillation heating in step J, accounting for 20-40% of the total heat load of distillation, significantly reducing the energy consumption of the distillation process and realizing the cascade utilization of energy.

[0032] 107. After step F is completed, step G is executed to remove the workpiece from the plate. The anti-static conveying mechanism transports the dried workpiece to the anti-static storage box for storage, so as to avoid the workpiece being contaminated or damaged by static electricity during subsequent transportation and to ensure the cleanliness and integrity of the workpiece after cleaning.

[0033] 201. While all steps of workpiece processing are performed simultaneously, step H, cleaning agent condensation and reuse, is executed. The cleaning agent gas generated in step B, atomization cleaning, is introduced into the cleaning agent condensation and recovery unit through a pipeline. In step H, the condensed and collected liquid cleaning agent is filtered to remove solid impurities before being returned to the cleaning process for reuse. The cleaning agent condensation and recovery unit adopts a cross-coil structure. Its principle is to improve the condensation and recovery efficiency by extending the cooling path and residence time of the atomized reagent in the condensation unit, ensuring that the condensation and recovery rate is not less than 98%. The filtration operation can effectively prevent impurities from clogging the atomization nozzle, ensuring the uniformity of atomization cleaning, while improving the purity of the recycled cleaning agent and avoiding the impact of impurity residue on the cleaning effect of precision workpieces.

[0034] 202. Similarly, in step I, the rinsing agent is condensed and reused. The rinsing agent gas generated in step D is introduced into the rinsing agent condensation and recovery unit. In step I, the condensed and collected liquid rinsing agent is filtered to remove solid impurities and then returned to the rinsing process for reuse. The rinsing agent condensation and recovery unit also adopts a cross-coil structure. After condensation, the collected liquid rinsing agent is filtered to remove solid impurities and then returned to the rinsing process for reuse. This step, together with the rinsing agent condensation and reuse step, forms a symmetrical reagent recovery cycle, constituting the core link of the closed-loop utilization of reagents, reducing reagent consumption and resource waste.

[0035] 203. The gases that are not completely condensed in steps H and I are then subjected to uncondensed gas distillation in step J. Both types of incompletely condensed gases are introduced into the distillation equipment. In step J, the fractional distillation is achieved based on the difference in boiling points between the cleaning agent and the rinsing agent. The boiling point of the cleaning agent is ≥230℃, and the boiling point of the rinsing agent is 98-100℃. The operating pressure is atmospheric pressure, and the distillation temperature is controlled between 80-160℃. Within this temperature range, the rinsing agent will completely vaporize, while impurities such as cleaning agent and flux residues remain at the bottom of the distillation equipment, achieving efficient separation. Simultaneously, the distillation equipment employs an energy-saving heating method, which can be either air-source heat pump heating or MVR heating. Compared to traditional heating rods, energy consumption is reduced by more than 30%, meeting the process goals of energy conservation and environmental protection. Its principle is to utilize the difference in boiling points of different substances to achieve gas-liquid separation through temperature control, ensuring the purity of the regenerated reagent.

[0036] 204. Finally, perform step K for graded diversion and reuse. The cleaning agent and rinsing agent, which have been separated and purified by distillation in step J, are diverted to the corresponding cleaning agent storage tank and rinsing agent storage tank through diversion pipes. The storage tanks are equipped with concentration meters to monitor the reagent purity in real time. When the purity is lower than 99%, the distillation parameters will be automatically adjusted or the reagent will be replaced. The two reagents can be repeatedly and stably used for atomization cleaning in step B and rinsing treatment in step D, forming a complete reagent closed-loop cycle to ensure the stability of the cleaning and rinsing effect.

[0037] The entire process is as follows: First, the precision workpiece to be cleaned is placed on the anti-static conveyor. After starting the equipment, the workpiece sequentially undergoes the following steps: Step A (workpiece pretreatment), Step B (atomized cleaning), Step C (reagent isolation and air cutting), Step D (rinsing), Step E (rinsing and air cutting), Step F (hot air drying), and Step G (workpiece removal), completing the removal of surface flux residue. During this process, Step H (cleaning agent condensation and reuse) and Step I (rinsing agent condensation and reuse) operate simultaneously, achieving preliminary reagent recovery and reuse. Uncondensed gas is purified by Step J (uncondensed gas distillation) and then reused through Step K (graded diversion), forming a complete closed-loop reagent cycle. During operation, the electric butterfly valve and anemometer work together to dynamically maintain pressure balance in each area; the heat exchange unit continuously recovers waste heat from Step F, providing energy for gas preheating and distillation heating; the concentration meter monitors reagent purity in real time to ensure stable cleaning and rinsing effects; and multi-unit gradient processing and filtration operations ensure efficient reagent utilization and workpiece cleaning quality.

[0038] In other embodiments, the energy-saving heating method of the distillation equipment in step J can also be replaced by solar heating or geothermal heating, which can also achieve the effect of reducing energy consumption. The core is to replace the traditional heating rod with renewable energy or high-efficiency energy-saving heating technology, which meets the energy-saving goal of the process. The method of adjusting the exhaust volume by electric butterfly valve can also be replaced by adjusting the size of the ventilation opening or using a variable frequency fan. Both can dynamically maintain pressure balance. The principle is to control the air pressure in each area by different air volume adjustment methods to avoid reagent crossflow. The cross coil structure of the condensation recovery unit in steps H and I can also be replaced by a spiral coil or shell and tube structure, which can also extend the cooling path and ensure the condensation recovery rate. The core is to increase the contact time between the reagent and the cooling medium by optimizing the coil structure, thereby improving the condensation effect.

[0039] This process, through the continuous execution of steps A to K, eliminates the need for pure water rinsing, achieving zero wastewater discharge, reducing environmental pollution and wastewater treatment costs, and solving the problems of high pressure and high cost in traditional wastewater treatment processes. The recycling of cleaning and rinsing agents through steps H, I, J, and K reduces reagent consumption, lowers production consumable costs, and minimizes resource waste. The reagent isolation air cutting and dynamic pressure regulation in step C work together to effectively prevent cross-contamination of reagents, while the distillation separation in step J ensures the purity of the regenerated reagents, guaranteeing the stability of cleaning quality for precision workpieces. The entire process is seamless, adaptable to batch production needs, improving cleaning efficiency while balancing environmental friendliness and economy, and is suitable for cleaning flux residues from various precision workpieces.

[0040] Finally, it should be noted that the cleaning process based on a distillation separation and rinsing agent regeneration cycle system disclosed in the embodiments of the present invention is only a preferred embodiment of the present invention and is only used to illustrate the technical solution of the present invention, not to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A cleaning process based on a distillation separation and rinsing agent regeneration and circulation system, characterized in that, Includes the following steps: Step A: Pre-processing of workpieces before boarding. Precision workpieces are boarded and pre-processed to remove surface dust and large impurities. Step B, atomized cleaning: The workpiece is sent into the cleaning area, and the cleaning agent is atomized and sprayed onto the surface of the workpiece after Step A to dissolve and remove the flux residue on the surface of the workpiece. At the same time, the used cleaning agent is collected. Step C, reagent isolation air cutting: The workpiece after step B is treated with reagent isolation air cutting to blow away the residual cleaning agent droplets on the surface of the workpiece and prevent the cleaning agent from mixing into subsequent processes. Step D, rinsing treatment: The workpiece is sent into the rinsing area, and the regenerated rinsing agent is sprayed onto the surface of the workpiece after step C to remove the residual cleaning agent on the surface of the workpiece, while the used rinsing agent is collected. Step E: Air cutting after rinsing. The workpiece treated in step D is air-cut to remove the regenerated rinsing agent droplets adhering to the surface of the workpiece. Step F, hot air drying: hot air is blown onto the workpiece after step E to completely evaporate the residual regeneration rinsing agent on the workpiece surface. Step G: Workpiece removal. The dried workpiece is removed from the plate and stored.

2. The cleaning process according to claim 1, characterized in that, Step B, which involves simultaneously collecting the used cleaning agent, includes step H, where the cleaning agent is condensed and reused. The cleaning agent gas generated by the atomized cleaning in step B is introduced into the cleaning agent condensation and recovery unit. After condensation treatment, liquid cleaning agent is obtained and returned to the cleaning process for reuse. Step D, which involves collecting used rinsing agent, includes: Step I, rinsing agent condensation and reuse, in which the rinsing agent gas generated in Step D is introduced into the rinsing agent condensation and recovery unit, and after condensation, liquid rinsing agent is obtained and returned to the rinsing process for reuse. Also includes: Step J: Distillation of uncondensed gas. The cleaning agent gas that was not completely condensed in step H and the rinsing agent gas that was not completely condensed in step I are introduced into the distillation equipment together, and the purification of the two reagents is achieved by fractional distillation separation. Step K involves graded diversion and reuse, where the cleaning agent and rinsing agent purified by distillation in step J are diverted to their respective cleaning agent storage tanks and rinsing agent storage tanks for reuse in the atomization cleaning of step B and the rinsing treatment of step D.

3. The cleaning process according to claim 2, characterized in that, In step F, the waste heat generated by hot air drying is recovered and reused through a heat exchange unit, and the temperature of the waste heat is 80-100℃; the waste heat is used to preheat the cleaning agent gas in step H and the rinsing agent gas in step I, and the temperature of the gas after preheating is 40-60℃ and 15-30℃ lower than the boiling point of the corresponding reagent; the waste heat can also assist in the distillation heating in step J.

4. The cleaning process according to claim 2, characterized in that, In step J, the fractional distillation is based on the difference in boiling points between the cleaning agent and the rinsing agent. The boiling point of the cleaning agent is ≥230℃, and the boiling point of the rinsing agent is 98-100℃. The operating pressure is atmospheric pressure, and the distillation temperature is controlled at 80-160℃.

5. The cleaning process according to claim 1 or 2, characterized in that, In step B, the atomization cleaning stage employs at least three continuous cleaning units, each set up relatively independently; in step D, the rinsing stage employs at least four continuous rinsing units, each set up relatively independently, with the workpiece sequentially passing through each unit to complete the corresponding process; in step B, the step of simultaneously collecting the used cleaning agent includes: each cleaning unit is equipped with a cleaning fluid collection area, where the used liquid cleaning fluid is collected, and each collection area is equipped with a filtration device, with the filtered cleaning fluid collected in a cleaning fluid storage tank; in step D, the step of simultaneously collecting the used rinsing agent includes: each rinsing unit is equipped with a rinsing fluid collection area, where the used liquid rinsing fluid is collected, and each collection area is equipped with a filtration device, with the filtered rinsing fluid collected in a rinsing fluid storage tank.

6. The cleaning process according to claim 5, characterized in that, In step A, the workpiece board preprocessing includes a first workpiece board preprocessing and a second workpiece board preprocessing. The first workpiece board preprocessing performs boarding processing on the precision workpiece and preprocesses the workpiece surface to remove surface dust and large impurities. The second workpiece board preprocessing is performed after the first workpiece board preprocessing. The workpiece surface image is captured for large impurity analysis. Based on the analysis results, a judgment is made on whether to perform atomization cleaning. If there are still large impurities exceeding the threshold, a second process to remove surface dust and large impurities is performed. If there are no large impurities or there are large impurities within the threshold range, proceed directly to step B; in step D, the rinsing agent is circulated at a rate of 30-50 liters per hour.

7. The cleaning process according to claim 2, characterized in that, A liquid-prevention isolation zone is set up between the cleaning zone and the rinsing zone to physically prevent liquid cross-contamination. The liquid-prevention isolation zone is equipped with baffles that are inclined towards the cleaning zone and the rinsing zone respectively, for physically isolating the cleaning liquid and rinsing liquid in their respective areas. The baffles are spaced apart and have diversion channels. The liquefied cleaning liquid and rinsing liquid are guided to their respective cleaning liquid storage tanks and rinsing liquid storage tanks through the diversion channels. In step J, the distillation equipment adopts an energy-saving heating method, which is air source heating or MVR heating.

8. The cleaning process according to claim 2, characterized in that, The air volume is adjusted by an electric butterfly valve, and the pressure balance of the atomized cleaning, rinsing and isolation areas is dynamically maintained in conjunction with the real-time data monitored by the anemometer.

9. The cleaning process according to claim 2, characterized in that, Both the cleaning agent condensation recovery unit and the rinsing agent condensation recovery unit adopt a cross-coil structure.

10. The cleaning process according to claim 2, characterized in that, In step H, the condensed and collected liquid cleaning agent is filtered to remove solid impurities and then returned to the cleaning process for reuse. In step I, the condensed and collected liquid rinsing agent is filtered to remove solid impurities and then returned to the rinsing process for reuse.

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