PGMEA solvent recycling membrane system and operation method thereof

Abstract

The invention relates to membrane system engineering for recycling wet electronic chemicals, and provides a purification and recycling platform for a PGMEA (propylene glycol methyl ether acetate) solvent. The platform is sequentially provided with pretreatment, contact and phase separation, selective membrane separation, a membrane contactor and polishing filtration, and a three-way valve and a small tank are connected in parallel at the near discharge end to form a backflow branch; and arranging an online sensor at the key section, and implementing gating by a controller according to a process threshold value and a release threshold value: when the process threshold value is exceeded, switching to a small tank for isolating backflow and linking two-section type in-situ cleaning, and when the release threshold value is met, releasing and generating a tracing record with a timestamp. According to the scheme, moisture, particles, TOC and dissolved gas are cooperatively controlled on the premise that membrane materials are not limited, the probability that abnormal batches enter a finished product section is reduced, the reset time is shortened, and the one-time release stability and traceability are improved.

Description

Technical Field

[0001] This invention relates to purification and reuse technology for wet electronic chemicals, belonging to the fields of membrane system engineering and online quality control, and particularly to a reuse platform for propylene glycol methyl ether acetate (PGMEA) solvents and its operating method. Background Technology

[0002] PGMEA-type solvents are widely used in wet processes such as photoresist formulation, coating, and cleaning. Recycling typically requires moderate energy consumption while simultaneously maintaining stable control over multiple quality indicators, including trace moisture, submicron particles, dissolved gases, and volatile impurities. Existing recycling routes primarily rely on distillation, adsorption, or single-membrane units: distillation mainly targets volatility differences but has limited effectiveness in suppressing submicron particles and dissolved gases; adsorption is susceptible to the state of the adsorbent and the regeneration and activation effect; single-membrane routes involve a trade-off between transmembrane mass transfer and antifouling, making it difficult to achieve long-term simultaneous compliance with multiple indicators. In actual production, even if parameters within a single unit meet short-term standards, cross-unit coupling can still lead to problems such as the mutual attraction of moisture and particles, flux decline, and fluctuations in recycled quality.

[0003] On the other hand, quality release in many cases remains decoupled from the valve topology and online monitoring at the equipment level. Common practices include "single-point online release combined with manual release" or "offline sampling followed by decision-making." When slow drift or short-term disturbances occur within or between batches, without a material diversion and physical isolation mechanism directly linked to the release action, abnormal batches can easily enter the finished product section along the main line, causing recontamination and weakening traceability. Even with post-incident cleaning and recovery, if a closed loop is not formed with the control strategy and valve position timing, the reset time is long and the restart fluctuations are large, making it difficult to ensure batch-to-batch consistency and process capability. Even with the introduction of membrane contactors or some type of online monitoring, if improvements remain at the unit level, system-level cross-contamination risks, short-circuit flow, and integrated reset remain difficult to effectively address. Summary of the Invention

[0004] Technical problems to be solved Without pre-setting specific membrane materials or filter microstructures, a holistic system engineering approach is proposed, which couples pretreatment, organic phase contact and separation, selective membrane separation, membrane contactors and polishing units with valve topology, online monitoring and control gating in a closed loop. Under steady-state and disturbed conditions, it achieves coordinated and stable control of multiple indicators such as moisture, submicron particles, dissolved gases and organic residues; it can immediately isolate and quickly reset abnormalities when deviations occur; and it improves the stability of first-release and batch-to-batch consistency through a traceable release mechanism.

[0005] Technical solution To achieve the above objectives, this invention proposes a membrane system engineering platform and its operation method for the purification and reuse of PGMEA-type solvents. The platform sequentially sets up pretreatment, organic phase contact and separation, selective membrane separation, membrane contactor, and polishing filtration modules at the process level. A three-way valve assembly is installed near the discharge end and connected in parallel with a buffer tank to form a reflux branch, constructing a near-end physical isolation path. This reflux branch is connected to the inlet of either the organic phase contact and separation module or the inlet of the selective membrane separation module.

[0006] At the monitoring and control level, online sensor arrays are deployed at the pretreatment, membrane separation, membrane contactor, and discharge sections, including at least trace moisture and particle count sensors, and can be expanded to include parameters such as total organic carbon (TOC), temperature, pressure, and flow rate as needed. The controller and human-machine interface implement dual threshold gating of "process threshold - release threshold": when any upper limit indicator exceeds the process threshold but does not exceed the release threshold, the event drives the three-way valve to switch to the small tank buffer and return the material to the upstream inlet for reprocessing; when all indicators meet the release threshold, the finished product is released and a timestamped release record and batch traceability data are generated.

[0007] At the maintenance and reset level, the platform, valve positions, and pump positions work together to implement a two-stage on-site cleaning process: first, a homogeneous cleaning solvent is circulated, then a polar cleaning solvent is circulated, and finally, ultrapure water (UPW) rinsing is used to finish; a unified reset criterion and observation batch management are used to restore the system to normal release status. This solution forms an executable and traceable closed loop between the device layer, monitoring layer, control layer, and quality layer.

[0008] Beneficial effects Compared to solutions that rely solely on unit-level improvements or manual release, this invention forms a stable structure-control-quality closed loop at the system level, offering the following advantages: Firstly, by connecting the near-end three-way valve assembly in parallel with the small tank for reflux, abnormal materials can be physically isolated and reprocessed, reducing the probability of abnormal batches entering the finished product section and enhancing batch-to-batch consistency and traceability. Secondly, by using a two-stage in-situ cleaning and unified reset criteria, the cleaning and reset time is shortened and the reset consistency is improved; in the embodiment, the flux recovery rate after CIP reaches or exceeds a predetermined threshold. Third, by using dual threshold gating and state machine timing, we can achieve forward-looking identification of gradual offsets and automatically generate release records and batch traceability information, thereby improving process transparency and auditing convenience. Fourth, through the coordinated feedback of process sequence and online monitoring of multiple parameters, key indicators such as moisture, particulate matter, TOC and dissolved gases can be simultaneously and stably met, taking into account both energy consumption and operational efficiency. Attached Figure Description

[0009] Figure 1This is a schematic diagram of the overall process of the platform. The platform includes pretreatment (102), organic phase contact and separation (103, 104), selective membrane separation (105), membrane contactor (106) and polishing filtration (107) in sequence. A three-way valve group (108) is set near the discharge pipeline between the outlet of the polishing filtration module and the release port (114), and is connected in parallel with the small tank buffer unit (109) to form a return branch. The return pipeline (110) returns to one of the inlets of the organic phase contact and separation module or the selective membrane separation module. Online sensors (111) are arranged in the pretreatment, membrane separation, membrane contactor and discharge sections, and are connected to the controller and human-machine interface (112) for signal communication.

[0010] Figure 2 This is a schematic diagram of the reflux topology of the three-way valve assembly and the small tank buffer. The three-way valve assembly (108) has three working positions: release position, buffer position, and bypass position. In the buffer position, the material is introduced into the small tank (109) from the upstream via the three-way valve and returns to the upstream inlet via the reflux pipeline (110). In the release position, the material goes to the release port (114) via the discharge pipeline. The reflux pipeline can be optionally equipped with a check valve (115) and a sampling valve (116) to prevent backflow and facilitate low-shear sampling.

[0011] Figure 3 This is a schematic diagram of the membrane contactor structure. It shows the shell-side inlet (1061) and shell-side outlet (1062), the interface (1063) communicating with a vacuum or inert gas, and the guide vanes (1064) arranged inside the shell to reduce bypass short-circuit flow.

[0012] Figure 4 This is a schematic diagram of the online monitoring and human-machine interface elements. The trend window sets the reference lines for process thresholds and release thresholds, and displays schematic curves for parameters such as moisture and particle size; the right side shows the event log and release record fields, with column headers including time, event, processing, and batch number / signature; the bottom displays the valve position and pump position status. The HMI (112) interacts with the online sensor (111) and valve-pump unit.

[0013] Figure 5 This is a schematic diagram of the on-site cleaning interlock and valve position sequence. The timeline sequentially displays the same-system cleaning, polarity cleaning, and UPW flushing stages; during the cleaning stage, the three-way valve (108) is in the reflux position and is locked for release. After passing the retest, it is reset and released again. The diagram shows the V108 valve position status bar and the release status bar to illustrate the correspondence between the valve position / pump position sequence and the release status.

[0014] The accompanying drawings are all schematic diagrams and are only used to illustrate the principles and structural relationships of the present invention. They are not limited to scale or dimensions.

[0015] Figure label: 101 Feed; 102 Pretreatment; 103 Contactor; 104 Phase Separation Tank; 105 Selective Membrane Separation; 106 Membrane Contactor; 1061 Shell-side Inlet; 1062 Shell-side Outlet; 1063 Vacuum or Inert Gas Interface; 1064 Flow Guide Plate; 107 Polishing Filter; 108 Three-way Valve Assembly; 109 Small Tank Buffer; 110 Return Line; 111 Sensor Array; 112 Controller and Human-Machine Interface (HMI); 113 Clean-in-Place (CIP) Liquid Supply Unit; 114 Release Port. Detailed Implementation

[0016] Unless otherwise stated, parameters not specified in the embodiments are taken as conventional values ​​in the art; the same technical feature may be combined with each other in different embodiments. Each embodiment is developed around the system coordination of process sequence—valve group parallel small tank reflux—multi-parameter online monitoring—dual threshold gating—two-stage CIP—release traceability, in order to support the coordinated and stable control of indicators such as moisture, particulate matter, total organic carbon (TOC) and dissolved gases.

[0017] Terminology and Measurement Methods Process threshold and release threshold: Two levels of thresholds are set for upper limit quality indicators; when any indicator exceeds the process threshold but does not exceed the release threshold, it enters the abnormal path (small tank isolation reflux and on-site cleaning is performed); when all indicators meet the release threshold, it is released.

[0018] Trace moisture: Sampling is performed online / offline using the Karl Fischer method (coulometric or volumetric method), or calibrated using an online thin-film capacitance analyzer with standard materials.

[0019] Process thresholds and release thresholds: used for process gating (threshold lines / reference lines on HMI).

[0020] Control Limits (UCL / LCL): Used for SPC control charts (observation batch "Tighten Control Limits").

[0021] Center line (CL): The mean line of the control chart.

[0022] Particle counting: The light obscuration method with a threshold of ≥0.05 μm was used; the statistical standard is expressed in "particles per mL". -1 "express.

[0023] TOC: Determined using online or offline oxidation methods, expressed in mg·L⁻¹. -1 "count.

[0024] Flux: expressed in L·m -2 ·h -1 (LMH) is the unit of measurement; transmembrane pressure difference is expressed in MPa; linear velocity is expressed in m·s. -1"Calculation. In the text, HMI refers to Human-Machine Interface, CIP refers to Clean In-Place (CIP), UPW refers to Ultrapure Water, and EWMA refers to Exponentially Weighted Moving Average."

[0025] Observation batch control: After resetting, the first 1 to 3 batches can be set as observation batches, and tightened statistical control limits (UCL / LCL) can be applied to the Shewhart / EWMA control chart; after the observation period expires and the release threshold is continuously met, the normal control limits are restored.

[0026] System Structure See Figures 1-5 The platform includes sequentially connected pretreatment, organic phase contact and separation, selective membrane separation, membrane contactor and polishing filtration modules; a three-way valve group and a small tank buffer are set up near the discharge end to form a reflux branch connected in parallel with the main line, and the reflux pipeline is connected to the inlet of the contact and separation or membrane separation; an online monitoring array (including at least moisture and particle count) is arranged in the pretreatment, membrane separation, membrane contactor and discharge sections, and is linked with the controller and human-machine interface.

[0027] Preferably, the three-way valve assembly has three positions: "release, return, and close," and has a double-blocking and venting structure to prevent backflow; the effective volume of the small tank corresponds to the retention volume of the main flow rate for 1 to 10 minutes, and is equipped with liquid level and conductivity monitoring and inert gas protection interfaces; the return pipeline is equipped with a check valve and a sampling valve, with the sampling valve located in the low-shear section of the return pipeline.

[0028] Control and release gating See Figure 4 The controller periodically collects online parameters and compares them with process thresholds and release thresholds. It executes valve and pump position timing according to the state machine: when any upper limit indicator exceeds the process threshold but does not exceed the release threshold, the three-way valve is switched to the small tank buffer position and the flow is returned to the upstream inlet for reprocessing; when all indicators meet the release threshold, the finished product is released and a release record with a timestamp and batch traceability data are generated.

[0029] Two-stage in-situ cleaning and resetting See Figure 5 When the process threshold is exceeded or the planned maintenance window is entered, the platform performs a two-stage in-situ cleaning in reflux mode: first, homologous cleaning solvent is circulated, then polar cleaning solvent is circulated, and finally, UPW rinsing is used to finish; the release port is closed during CIP. After cleaning, a reset is determined based on criteria such as online retesting and throughput recovery rate. After reset, the first 1-3 batches can be set as observation batches and tightened control limits are applied; after the observation period expires and the release threshold is continuously met, the normal control limits are restored.

[0030] Example 1: Standard Operating Condition The system was run according to the parameter window settings (see Table 4). After 24 hours of continuous steady-state operation, samples were collected and tested at five nodes: feed, contact and phase separation outlet, membrane separation outlet, membrane contactor outlet, and after polishing. Moisture content was measured using the Karl Fischer method, particle size was measured using the photoresist method (threshold ≥ 0.05 μm), and TOC was measured using the oxidation method. Flux was recorded before and after CIP for recovery rate calculation (J_afterCIP / J_baseline × 100%). The test results are shown in Table 1.

[0031] Table 1. Comprehensive data for representative batches (Example 1; steady-state operation for 24 hours; parameter window shown in Table 4) Note: This table contains point-in-time measurements; the symbol "—" indicates no sampling or inapplicability (only valve / pump position and timing are recorded during the CIP phase); "ND" indicates below the method detection limit, not equivalent to 0. Units are listed in the column header.

[0032] Results and Analysis: Moisture, particulate matter, and TOC all met the release threshold after polishing; flux recovered to ≥90% after CIP, meeting the reset criterion. The five-node data show that water content mainly decreased during the contact and phase separation stages and the membrane contactor stage, from 1200 mg·kg⁻¹. -1 Reduced to 420 mg·kg -1 It further decreased to 290 mg·kg -1 The final result was 240 mg / kg. -1 The bulk decrease in particle size (≥0.05μm) also occurred during the contact and phase separation stages, from 5.0 particles per mL. -1 Reduced to 1.2 units / mL -1 It further decreased to 0.9 units / mL. -1 The final value was 0.6 units per mL. -1 TOC is reduced primarily through contact and phase separation, with membrane contactors playing a secondary role. The safety margin after polishing relative to the release threshold is approximately: moisture 20%, particles 40%, TOC 20%.

[0033] Example 2: Abnormal Isolation and Reset Based on Example 1, the feed moisture content was temporarily increased (e.g., to 600–800 mg·kg). -1 The system is maintained for 10–15 minutes to generate disturbance; when any indicator exceeds the process threshold, the system switches to small tank buffer reflux and performs a two-stage CIP. Key events, parameters, and valve position timings are shown in Table 2.

[0034] Table 2 Timeline of Abnormal Isolation and Reset (Example 2; Disturbance—Isolation Return—Two-Stage CIP—Reset) This table contains point-in-time measurements; the symbol "—" indicates no sampling or inapplicability (only valve / pump position and timing are recorded during the CIP phase); "ND" indicates below the method detection limit, not equivalent to 0. Units are listed in the column header.

[0035] Results and Analysis: After exceeding the process threshold, the system completes valve position switching and enters reflux within t_trigger; the durations of homologous cleaning, polar cleaning, and UPW rinsing are t1, t2, and t3, respectively, and the total CIP duration is T_CIP = t1 + t2 + t3. The total time from triggering to recovery is T_recovery; after reset, N_batch (1~3) observation batches are set, and key indicators continuously meet the release threshold without rebound. If the throughput is recorded, the throughput recovery rate after CIP is ≥90%.

[0036] Example 3: Statistical Performance and Control First-release rate, process capability index (Cpk), and EWMA alarm advance were evaluated during continuous batch operation. Method: Using "Control Example A" as a baseline, both used the same raw materials, target thresholds, and SOPs and equipment, differing only in control / topology: Control Example A did not employ dual-threshold gating and had no near-end recirculation; this platform employed dual-threshold gating and near-end recirculation. Results from 30 batches were compared; Cpk was calculated using a combined moisture / particle / TOC index; the EWMA smoothing coefficient λ was set to 0.1–0.3, and the sampling interval was set according to the HMI. Statistical results are shown in Table 3.

[0037] Statistical methods (1) First-pass yield: The batch was Bernoulli tested and counted as “qualified batches / total batches”. The 95% confidence interval was the Wilson score interval; the two-proportion z-test (pooled variance) was used for intergroup comparisons, and the directional one-sided and two-sided p-values ​​were reported simultaneously.

[0038] (2) Cpk (Comprehensive): Based on batch Cpk i Using a sample of (i = 1…30), calculate the within-group mean and standard deviation; the 95% CI is calculated using the t-score confidence interval; between-group comparisons are performed using the Welch t-test or the Mann-Whitney test (when the distribution is skewed). This example reports a point estimate of the aggregated Cpk; for statistical inference, the 95% CI and p-value can be obtained using the aforementioned method based on batch Cpk data.

[0039] (3) EWMA alarm lead time: The lead time in each disturbance experiment is used as the sample (n=5n for this platform). The 95% CI of the median of a single group can be given by the order statistic; the significance test adopts the single-sample sign test (direction hypothesis "lead time > 0min").

[0040] (4) Significance threshold and expression: Unless otherwise stated, the significance threshold α = 0.05; p-values ​​are rounded to three decimal places; confidence intervals are rounded to one percentage point for proportional classes and to one decimal place for time classes.

[0041] Table 3 Statistical Performance and Controls (30 batches; Control Example A is "without dual threshold gating and no backflow") Results and Analysis Taking 30 batches as an example, the first-pass release rate of this platform was 28 / 30 (93.3%), while the control group was 23 / 30 (76.7%); Wilson 95% CI is shown in Table 3. The two-proportion z-test showed a two-sided p=0.071, and a one-sided p=0.035 under the directional superiority hypothesis, indicating a statistically significant upward trend in the first-pass release rate. The median EWMA alarm lead time was approximately 11 minutes; if positive lead time was observed in 5 / 5 disturbances, the one-sided p=0.031, indicating a significant forward-looking alarm capability. The combined Cpk (1.45 vs 1.12) showed improved process capability; its significance can be calculated using the above method while retaining batch-by-batch CpkiCpk_iCpki for further quantification.

[0042] Parameter window (representative) To facilitate engineering setup and verification, representative parameter windows for each unit / stage are provided. These windows can be adjusted according to the standard operating procedure (SOP) and do not constitute a limitation of the present invention (see Table 4). For ease of comparison and reproduction, the selected points in the examples are: transmembrane pressure difference 0.60 MPa, flux setting 25 L·m⁻². -2 ·h -1 (LMH), small tank residence time τ=6min; corresponding data and statistical results are shown in Tables 1 to 3.

[0043] Table 4 Parameter Window (Representative; can be adjusted according to SOP, and does not constitute a limitation of the present invention) Note: "Example settings" are used to illustrate the selected points of the embodiment; those skilled in the art can make equivalent adjustments within the listed scope without departing from the spirit and scope of the invention. "—" indicates not detected or not applicable.

[0044] This window covers key variables for operation, monitoring, and maintenance; tightening the process threshold by 5%–15% relative to the release threshold without significantly impacting release efficiency can improve gating sensitivity and response speed. It is recommended to clearly define permissible deviations, deviation handling rules, and reset criteria in the Standard Operating Procedure (SOP).

[0045] Valve position state matrix To facilitate understanding of the correspondence between valve / pump position and release status, an exemplary matrix for common operating conditions is provided, as shown in Table 5 (see Table 5). Figure 2 and Figure 5 ).

[0046] Table 5 Valve Position Status Matrix (Example; see also) Figure 2 and Figure 5 ) Explanation and Analysis: When any upper limit indicator exceeds the process threshold, the valve position switches to the buffer position, the material is introduced into the small tank and reprocessed through the reflux pipeline; after retesting and meeting the release threshold, it switches to the release position. This logic is similar to... Figure 2 The return topology and Figure 5 The timing should be consistent. It is recommended to specify the power failure / gas failure safety position (preferably the return position with release interlock) in the SOP.

[0047] Optional implementation methods and variations Without departing from the spirit of this invention, adjustments can be made to the reflux connection location, the three-state structure of the valve assembly, the online parameter configuration, and the CIP timing and reset criteria. For example, the reflux can be connected to one of the inlets before or after contact and phase separation. In addition to moisture and particles, online monitoring can include TOC, temperature, pressure, and flow rate as needed on site. The number of observation batches and control limits after reset can be optimized according to the operating conditions. The parameter window is for engineering setting reference and does not constitute a limitation on membrane material, pore size, differential pressure, or timing unless otherwise specified in the claims.

[0048] Industrial applicability The platform and method of this invention can be implemented in semiconductor, display and other recycling production lines that use PGMEA-type solvents. The required components and instruments are readily available or conventionally manufactured. The parameter window and threshold strategy can be equivalently adjusted with the SOP. The control algorithm details, valve group microstructure details and two-stage CIP formulations in this application and the parallel application are clearly defined, which facilitates modular integration and large-scale deployment and has clear industrial applicability.

Claims

1. A membrane system engineering platform for the purification and reuse of propylene glycol methyl ether acetate (PGMEA) solvents, characterized in that: The platform includes a pretreatment module, an organic phase contact and phase separation module, a selective membrane separation module, a membrane contactor module, and a polishing and filtration module connected in sequence. A three-way valve assembly is installed between the near end of the discharge pipeline and the return pipeline between the outlet and the release port of the polishing and filtering module. The three-way valve assembly is connected in parallel with the small tank buffer unit to form a return branch. The return pipeline is connected to at least one of the inlet of the organic phase contact and phase separation module or the inlet of the selective membrane separation module. An online sensor array is installed in the pretreatment section, membrane separation section, membrane contactor section and discharge section. The online sensor array includes at least one or more of a trace moisture sensor and a particle counting sensor. It also includes an on-site cleaning and supply unit connected to the pipeline; and a controller and human-machine interface (HMI) electrically connected to the three-way valve group, pump equipment and the online sensor array. The controller is configured to make gating decisions based on process thresholds and release thresholds: when any upper limit quality index exceeds the process threshold but does not exceed the release threshold, the three-way valve group is driven to allow the material to flow back to the upstream inlet through the small tank buffer unit for reprocessing. When all indicators meet the release threshold, the finished product release is initiated; and a release record containing a timestamp and batch traceability data are generated. The controller is also configured to, in the reflux state, execute the valve position and pump position timing of in-situ cleaning through the cleaning loop formed by the in-situ cleaning supply unit and the pipeline.

2. The platform according to claim 1, wherein, The online sensor array also includes at least one of total organic carbon (TOC), temperature, pressure, and / or flow rate.

3. The platform according to claim 1, wherein, The effective volume of the small tank buffer unit corresponds to the retention rate of the main flow rate of the system from 1 to 10 minutes, and it is equipped with interfaces for liquid level and conductivity monitoring and inert gas protection.

4. The platform according to claim 1, wherein, The three-way valve assembly has three working positions: release position, backflow position, and closed position, and has a double blocking and venting structure to prevent backflow.

5. The platform according to claim 1, wherein, The selective membrane separation module has a transmembrane pressure difference of 0.20–1.50 MPa and a flux of 5–50 L·m⁻¹. -2 ·h -1 .

6. The platform according to claim 1, wherein, The membrane contactor module operates under negative pressure conditions on the housing side (absolute value of vacuum gauge pressure ≥ 0.05 MPa), or under inert gas replacement conditions, or under a combination of both conditions. A guide vane is installed inside the housing to reduce bypass short-circuit flow.

7. The platform according to claim 1, wherein, The nominal pore size of the polishing filter module is 0.05 to 0.10 μm, and the replacement criterion is a pressure difference ≥ 0.12 MPa or cumulative operation ≥ 100 h.

8. The platform according to claim 1, wherein, The reflux line is equipped with a check valve and a sampling valve. The sampling valve is located in the low-shear section upstream of the reflux pump, and the reflux line is connected to the inlet of the contact and phase separation unit or the membrane separation unit.

9. A method for operating the platform as described in any one of claims 1 to 8, characterized in that, include: (S1) Perform preprocessing; (S2) Perform organic phase contact and phase separation; (S3) Perform selective membrane separation under the set transmembrane pressure difference; (S4) Dissolved gases and / or trace impurities are removed via a membrane contactor under shell-side negative pressure or inert gas scavenging conditions; (S5) After polishing and filtration, the finished product is released or the small tank is returned based on the gating judgment of the process threshold and the release threshold. The on-site cleaning process, which is connected to the pipeline, includes a homologous cleaning solvent stage and a polar cleaning solvent stage, and ends with rinsing with ultrapure water (UPW).

10. The method according to claim 9, wherein, The release threshold for upper limit quality indicators includes moisture ≤300 mg·kg -1 Particle size (≥0.05 μm) ≤1.0 particles / mL -1 TOC ≤ 10 mg·L -1 The corresponding process threshold is tightened by 5% to 15%; the observation batch is set to 1 to 3 batches, the exponential weighted moving average (EWMA) smoothing coefficient λ is 0.1 to 0.3, and the reset criterion is that the throughput recovery rate is ≥90% and the release threshold is met.

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