Method for recycling a security filter cartridge

Abstract

The application discloses a security filter element recycling method, relates to the recycling and reuse technical field of a security filter element, and comprises the following steps: classification and evaluation, evaluating and classifying the pollution degree of the recycled security filter element, and then distributing the security filter elements of different classifications to different regeneration treatment processes; cleaning, cleaning the security filter element, and the cleaning scheme of the security filter element of different pollution degree classifications being different; and functional regeneration, regenerating at least part of the cleaned security filter element to ensure that the security filter element can meet the mechanical performance requirement. The application integrates the intelligent evaluation of the security filter element state, multi-mode collaborative cleaning and structure function recovery technology, forms a complete security filter element regeneration solution, can realize efficient and thorough cleaning of the security filter element, and guarantees the performance of the regenerated security filter element.

Description

Technical Field

[0001] This application relates to the field of recycling and reusing security filter elements, and more specifically, to a method for recycling and reusing security filter elements. Background Technology

[0002] Security filters, as a key component of industrial water treatment systems, primarily function to trap fine suspended particles that the pretreatment system fails to remove, protecting downstream reverse osmosis membranes or other precision filtration equipment from contamination and physical damage. As the system's "last line of defense," the working condition of the security filter cartridge directly affects the overall efficiency and stability of the water treatment system. Currently, the mainstream usage mode for security filter cartridges in industry is still "replacement-based," meaning that the cartridge is discarded and replaced with a new one when it becomes clogged. This mode not only leads to high system maintenance costs, but also results in discarded cartridges often being made of non-degradable materials such as polypropylene, which, when accumulated in large quantities, puts persistent pressure on the environment.

[0003] To reduce costs and alleviate environmental pressure, existing technologies have proposed several filter element cleaning and reuse methods, mainly including physical backwashing, chemical immersion cleaning, and mechanically assisted cleaning. However, all of these existing cleaning technologies have significant drawbacks:

[0004] Physical backwashing technology uses reverse water flow or compressed air to impact the surface of the filter element to remove trapped contaminants. It is simple to operate and low in cost, but it is only effective in removing contaminants attached to the surface of the filter material. It is almost ineffective against contaminants that have penetrated into the interior of the filter material. Furthermore, the reverse water flow can easily cause irreversible physical damage to the microstructure of the filter element. It is only suitable for lightly polluted scenarios where surface deposition is the main feature.

[0005] Chemical immersion cleaning involves soaking the filter element in acid, alkali, or oxidizing solutions to dissolve specific types of dirt. This method can penetrate into the filter media to remove contaminants, but it is highly selective in terms of dirt type. If the cleaning agent is not chosen properly, it can easily accelerate the aging and degradation of the filter media. In addition, the chemical cleaning process generates a large amount of waste liquid that requires secondary treatment, which is environmentally unfriendly and is usually limited to treating specific chemical dirt such as calcium scale and organic matter.

[0006] Mechanically assisted cleaning (such as brushing and ultrasonic cleaning) enhances cleaning depth and efficiency through direct physical action. Ultrasonic cleaning offers a large cleaning depth but significantly increases equipment investment and energy consumption; while mechanical brushing can directly target the contaminant layer, it suffers from poor cleaning uniformity and can easily cause physical damage to the filter element. These technologies are mostly suitable for high-value filter elements or special scenarios involving severe contamination.

[0007] Due to the aforementioned limitations of existing cleaning technologies, truly efficient and non-destructive regeneration of filter elements cannot be achieved. Consequently, the industrial sector still primarily relies on costly and polluting direct replacement. Therefore, improving the recycling efficiency of security filter elements has become a pressing technical problem for those skilled in the art. Summary of the Invention

[0008] In view of this, the purpose of this application is to provide a method for recycling and reusing security filter elements, so as to improve the recycling and reuse efficiency of security filter elements.

[0009] A method for recycling and reusing a security filter cartridge includes:

[0010] S10. Classification and assessment: The degree of contamination of the recovered security filter cartridges is assessed and classified.

[0011] S20. Cleaning: Clean the security filter element. The cleaning schemes for security filter elements classified according to different levels of contamination are different. The cleaning schemes include at least one of chemical cleaning, ultrasonic-assisted cleaning, and physical backwashing.

[0012] S30, Functional Regeneration: Regenerating at least partially cleaned security filter cartridges.

[0013] In some embodiments, in S10, the security filter element is classified into at least three categories based on the degree of contamination: lightly contaminated, moderately contaminated, and heavily contaminated.

[0014] In S20, lightly contaminated security filter elements are cleaned using a physical backwashing method; moderately contaminated security filter elements are cleaned using a combination of chemical cleaning and physical backwashing; and heavily contaminated security filter elements are cleaned using a combination of chemical cleaning and ultrasonic-assisted cleaning.

[0015] In some embodiments, in S10, the classification of the contamination level of the security filter element is based on at least one of pressure drop test, weight measurement, visual inspection, and microbial detection.

[0016] In some embodiments, in S10, the security filter element is classified into at least two categories based on the degree of structural deformation: slightly deformed and heavily deformed.

[0017] S30 includes the following steps:

[0018] S31. Shaping: The structure of heavily deformed security filter elements is restored using a heat-setting process.

[0019] In some embodiments, S30 further includes:

[0020] S32. Reinforcement: The security filter element after structural restoration is reinforced with a skeleton reinforcement technique, and the reinforcement is set at the skeleton deformation position of the security filter element.

[0021] S33. Sealing: Replace the sealing structure of the security filter element after structural restoration.

[0022] In some embodiments, the step prior to S10 is further included:

[0023] S00. Pre-treatment: Inspect the recovered security filter cartridges, remove obviously damaged ones, and record relevant information about the security filter cartridges.

[0024] The relevant information includes the model of the security filter element, the service life of the security filter element, and the filter medium of the security filter element.

[0025] In some embodiments, S00 also includes surface rinsing of the recovered security filter cartridge.

[0026] In some embodiments, step S30 is followed by:

[0027] S40. Performance verification: Conduct quality testing on the regenerated security filter cartridges. Security filter cartridges that pass the test are marked with the number of regenerations and performance parameters and enter the reuse stage. Security filter cartridges that fail the test enter the material recycling process.

[0028] The quality testing includes at least one of the following: filtration accuracy test, flux test, pressure resistance test, and sealing test.

[0029] In some embodiments, step S40 is followed by:

[0030] S50. Drying: Dry the qualified security filter element.

[0031] S60. Packaging: Package the dried security filter element and attach regeneration information for the security filter element.

[0032] In some embodiments, in S50, the security filter element is dehumidified and dried under conditions below the temperature tolerance threshold of the security filter element.

[0033] In S60, composite barrier membrane material is used to seal and package the security filter element.

[0034] The security filter cartridge recycling and reuse method provided in this application includes a classification and assessment step, a cleaning step, and a functional regeneration step. The classification and assessment step specifically involves assessing and classifying the recovered security filter cartridges according to their degree of contamination. Subsequently, different categories of security filter cartridges are assigned to different regeneration processes. Classifying the security filter cartridges effectively avoids the high costs and high contamination associated with traditional methods that require the complete replacement of all security filter cartridges, as well as preventing improper or over-cleaning caused by using the same cleaning and regeneration method for all cartridges. The cleaning step involves cleaning the security filter cartridges, with different cleaning schemes for cartridges classified according to their degree of contamination. The cleaning schemes include at least one of chemical cleaning, ultrasonic-assisted cleaning, and physical backwashing. This application integrates these three cleaning modes to automatically match the optimal cleaning combination based on the contamination characteristics of the security filter cartridges. The functional regeneration step involves regenerating at least partially cleaned security filter cartridges to ensure that they meet mechanical performance requirements.

[0035] Compared to related technologies, the security filter cartridge recycling and reuse method provided in this application organically integrates intelligent assessment of the security filter cartridge status, multi-mode collaborative cleaning, and structural function restoration technology to form a complete security filter cartridge regeneration solution. This solution can achieve efficient and thorough cleaning of the security filter cartridge, ensure the performance of the regenerated security filter cartridge, significantly extend the service life and regeneration efficiency of the security filter cartridge, and reduce the operation and maintenance costs of the water treatment system. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is a flowchart of the method for recycling and reusing security filter cartridges disclosed in an embodiment of this application;

[0038] Figure 2 This is a flowchart of the functional regeneration steps disclosed in an embodiment of this application. Detailed Implementation

[0039] This application discloses a method for recycling and reusing security filter elements to improve the recycling and reuse efficiency of security filter elements.

[0040] The embodiments will now be described with reference to the accompanying drawings. Furthermore, the embodiments shown below do not limit the scope of the invention as described in the claims. Additionally, the complete contents of the structures represented in the embodiments below are not limited to those necessary for the solution of the invention as described in the claims. It should be noted that, for ease of description, only the parts relevant to the invention are shown in the drawings. Unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0041] Combination Figure 1 The method for recycling and reusing security filter cartridges disclosed in this application includes the following steps:

[0042] S10. Classification and assessment: The recovered security filter cartridges are classified according to their degree of contamination. Subsequently, the security filter cartridges of different categories are assigned to different regeneration processes. Classifying the security filter cartridges can effectively avoid the high cost and high pollution caused by the traditional solution of discarding and replacing all security filter cartridges. It can also avoid improper cleaning or over-cleaning caused by using the same cleaning and regeneration method for all security filter cartridges.

[0043] S20. Cleaning: Cleaning the security filter element. Different cleaning schemes are used for security filter elements classified by different levels of contamination. The cleaning schemes include at least one of chemical cleaning, ultrasonic-assisted cleaning, and physical backwashing. This application integrates three cleaning modes—chemical cleaning, ultrasonic-assisted cleaning, and physical backwashing—to automatically match the optimal cleaning combination based on the contamination characteristics of the security filter element. For example, for complex contamination situations commonly found in greywater reuse systems, the cleaning agent formula and process parameters can be intelligently adjusted based on historical water quality data to achieve personalized treatment for each filter element.

[0044] S30, Functional Regeneration: Regenerate at least partially cleaned security filter elements to ensure that the security filter elements meet mechanical performance requirements.

[0045] Compared with existing technologies, the security filter cartridge recycling and reuse method disclosed in this application organically integrates intelligent assessment of the security filter cartridge status, multi-mode collaborative cleaning, and structural function restoration technology to form a complete security filter cartridge regeneration solution. This solution can achieve efficient and thorough cleaning of the security filter cartridge, ensure the performance of the regenerated security filter cartridge, significantly extend the service life and regeneration efficiency of the security filter cartridge, and reduce the operation and maintenance costs of the water treatment system.

[0046] In some embodiments disclosed in this application, in S10, the security filter element is classified into at least three categories based on the degree of contamination: lightly contaminated, moderately contaminated, and heavily contaminated. In S20, a differentiated cleaning strategy is implemented based on the different classification results. Specifically, the lightly contaminated security filter element can be cleaned using a physical backwashing method to ensure cleaning reliability while reducing damage to the security filter element. The moderately contaminated security filter element is cleaned using a combination of chemical cleaning and physical backwashing to effectively remove various specific types of dirt. The heavily contaminated security filter element is cleaned using a combination of chemical cleaning and ultrasonic-assisted cleaning to ensure thorough cleaning.

[0047] For example, the cleaning process of a moderately contaminated security filter element is as follows: First, a mixture of 0.5% sodium hydroxide and 0.1% sodium dodecyl sulfate is used for dynamic alkaline washing at 40°C for 20 minutes to efficiently remove and decompose the surface organic matter of the security filter element, thereby exposing the deep inorganic scale and creating penetration conditions for subsequent acid washing; then, dynamic rinsing with 2% citric acid is performed at room temperature for 15 minutes, supplemented by ultrasonic oscillation at 28kHz for 10 minutes, so as to fully dissolve the exposed inorganic salts with the acid solution. The acid washing step is performed after the alkaline washing step to prevent the organic membrane from hindering the penetration of the acid solution; finally, backwashing with water is performed to thoroughly remove the residual complex dirt through physical flushing.

[0048] A heavily contaminated security filter element undergoes the following cleaning process: First, the security filter element is pre-soaked for 30 minutes at a constant temperature of 40℃ using a mixture of pure water and 0.5% sodium dodecylbenzenesulfonate or other surfactants. During this time, the security filter element is ensured to be completely submerged to avoid cavitation residue affecting ultrasonic transmission. This step is used to fully wet and expand deep-seated silica scale and grease. Subsequently, ultrasonic mechanically assisted enhanced cleaning is performed. The ultrasonic transducer is periodically and dynamically offset along the slide rail by ±10mm to eliminate dead zones in the sound field. Simultaneously, a rotating brush operates synchronously at a speed of 15rpm to axially brush the surface of the security filter element. This cleaning process, through the synergistic effect of mechanical force and cavitation, can efficiently remove colloidal substances adhering to the surface of the security filter element.

[0049] Specifically, in S10 above, the classification of the contamination level of the security filter element includes at least one of pressure drop testing, weight measurement, visual inspection, and microbial testing. Combining multiple testing methods ensures the accuracy of the classification. Pressure drop testing can be performed using a filter element permeability tester or a differential pressure test bench with specialized fixtures to measure the resistance at both ends of the security filter element. Weight measurement can be performed using a high-precision electronic balance or a windproof precision balance to detect the weight of the security filter element. Visual inspection can automatically identify defects using a machine vision system composed of an industrial camera and a light source, or it can be manually confirmed using a magnifying glass or stereomicroscope. Microbial testing involves first collecting samples using a microbial aerosol sampler, then pre-treating them in a biosafety cabinet, and finally incubating them in a constant temperature incubator and using a colony counter to obtain the results.

[0050] In some embodiments disclosed in this application, in step S10, the security filter elements can be divided into two categories based on their degree of deformation: slightly deformed and heavily deformed. The slightly deformed security filter elements have a lesser degree of deformation than the heavily deformed ones, and the slightly deformed ones meet the performance requirements for direct use, while the heavily deformed ones do not. For the heavily deformed security filter elements, combined with... Figure 2 The above S30 may include the following steps:

[0051] S31. Shaping: A heat-setting process is used to restore the structure of severely deformed security filter elements. Specifically, the heat-setting process can be achieved using a hot air circulating oven. By utilizing the memory effect of the filter material softening under heat, the deformed parts of the security filter element spring back to their original shape under the support of the shaping fixture. This process is simple to operate and can quickly eliminate the bending and wrinkles of the security filter element skeleton, restoring the original size and roundness of the security filter element, thereby ensuring the filtration flow rate and compressive strength of the regenerated security filter element and extending its service life.

[0052] Furthermore, S30 may also include:

[0053] S32. Reinforcement: Reinforcement technology is used to add reinforcing components to the restored security filter element. Specifically, ultrasonic welding machines or hot melt adhesive dispensing machines can be used to install the reinforcement components. These components can be metal support rings or high-strength plastic clamps. By utilizing high-frequency frictional heat or the adhesive force of hot melt adhesive, the fasteners can be fixed to the weak points of the security filter element's skeleton, forming a composite stress layer. This effectively disperses the concentrated stress caused by fluid scouring and pressure differentials, ensuring that the structural strength of the regenerated security filter element meets requirements and preventing deformation or collapse during long-term operation. This significantly improves the overall rigidity and fatigue resistance of the regenerated security filter element.

[0054] S33. Sealing: Replace the sealing structure of the security filter element after structural restoration. Specifically, after removing the original sealing structure of the security filter element, an O-ring silicone seal can be installed at the junction of the end cap and the housing using an automatic dispensing machine or sealing ring pressing equipment. This utilizes the compressive elastic deformation of the material to fill the tiny assembly gaps, thereby blocking the bypass leakage of the filtrate and ensuring the reliable operation of the regenerated security filter element.

[0055] Of course, the above S32 and S33 can be performed selectively. For example, S32 can be performed only on security filter elements with abnormally severe deformation in the heavily deformed type. In S10, the sealing performance of each security filter element is tested to classify them into low-sealing and high-sealing types. S33 can be performed only on low-sealing security filter elements with low sealing performance, while high-sealing security filter elements that meet the sealing performance requirements do not need to undergo S32.

[0056] To improve recycling efficiency, combined with Figure 1 The steps preceding S10 may also include:

[0057] S00, Pre-treatment: A preliminary inspection is performed on the recovered security filter cartridges, and obviously damaged cartridges are removed to prevent unusable cartridges from entering subsequent stages. Simultaneously, relevant information about the security filter cartridges is recorded. This information includes the cartridge model, service life, and filter medium. This information serves as a basis for classifying and evaluating the security filter cartridges in S10, and as a selection criterion for cleaning and regeneration schemes for different security filter cartridges in S20 and S30.

[0058] Furthermore, S00 also includes a surface rinsing step for the recovered security filter element to pre-remove loose contaminants from the surface of the security filter element, thereby facilitating subsequent classification, evaluation, and cleaning of the security filter element.

[0059] In some embodiments disclosed in this application, the following step is included after S30:

[0060] S40. Performance Verification: The regenerated security filter cartridges undergo quality testing. Qualified cartridges, labeled with the number of regeneration cycles and performance parameters, enter the reuse stage. Failed cartridges are recycled. Quality testing includes at least one of the following: filtration accuracy testing, flow rate testing, pressure resistance testing, and sealing performance testing. Combining multiple testing methods ensures the regenerated security filter cartridges meet usage requirements. Specifically, filtration accuracy testing uses a particle counter to measure the impurity rejection rate before and after filtration, confirming the cartridge's ability to block impurities of the target size. Flow rate testing uses a flow meter and balance to measure the water output per unit time under a certain pressure, evaluating the cartridge's permeability and dirt-holding capacity. Pressure resistance testing uses a booster pump to pressurize and maintain pressure on the cartridge, checking for cracking or deformation under high pressure or backwashing. Sealing performance testing involves inflating the cartridge and observing pressure drop or bubbles to check for leaks in the sealing structure, preventing unfiltered water from leaking directly.

[0061] To facilitate the reuse of the security filter cartridge, step S40 includes the following steps:

[0062] S50. Drying: The qualified security filter element is dried to remove residual moisture from the micropores of the filter element, so as to prevent the growth of mold and bacteria during storage.

[0063] S60. Packaging: Package the dried security filter element to ensure it remains clean before use. Also include regeneration information to accurately track the filter element's lifespan and performance degradation. This ensures filtration quality while avoiding waste or risks associated with premature filter element failure or expired use.

[0064] Specifically, in order to ensure the performance of the security filter element, in S50, the security filter element is dehumidified and dried under conditions below the temperature threshold of the security filter element. For example, the drying temperature is controlled to be more than 20°C lower than the maximum temperature of the security filter element to avoid material aging caused by high-temperature drying. In S60, the security filter element is sealed and packaged with a composite barrier membrane material to prevent the regenerated security filter element from getting damp. Specifically, the composite barrier membrane material can be an aluminum foil composite membrane, an aluminized composite membrane, a pure polymer barrier membrane, etc., and this application does not limit it.

[0065] The terms "first" and "second," etc., used in the specification and claims of this application are used to distinguish different objects, not to describe a specific order, and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units may include steps or units not listed, but rather steps or units not listed. Additionally, in the description of embodiments in this application, "a plurality of" means two or more.

[0066] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Specific technical means in some embodiments may be incorporated, in whole or in part, into another embodiment unless explicitly excluded by another embodiment. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for recycling and reusing a security filter element, characterized in that, include: S10. Classification and assessment: The degree of contamination of the recovered security filter cartridges is assessed and classified. S20. Cleaning: The security filter element is cleaned, and the cleaning schemes for the security filter elements classified according to different levels of contamination are different. The cleaning schemes include at least one of chemical cleaning, ultrasonic-assisted cleaning, and physical backwashing. S30, Functional regeneration: Regenerating the security filter element after at least partial cleaning.

2. The method for recycling and reusing the security filter element as described in claim 1, characterized in that, In S10, the security filter element is classified into at least three categories based on the degree of contamination: lightly contaminated, moderately contaminated, and heavily contaminated. In step S20, the security filter element with slight contamination is cleaned using a physical backwashing method; the security filter element with moderate contamination is cleaned using a combination of chemical cleaning and physical backwashing; and the security filter element with heavy contamination is cleaned using a combination of chemical cleaning and ultrasonic assistance.

3. The method for recycling and reusing the security filter element as described in claim 2, characterized in that, In step S10, the classification of the contamination level of the security filter element is based on at least one of pressure drop test, weight measurement, visual inspection, and microbial detection.

4. The method for recycling and reusing the security filter element as described in claim 1, characterized in that, In step S10, the security filter element is classified into at least two categories based on the degree of structural deformation: slightly deformed and heavily deformed. S30 includes the following steps: S31. Shaping: The structure of the heavily deformed security filter element is restored using a heat-setting process.

5. The method for recycling and reusing the security filter element as described in claim 4, characterized in that, S30 also includes: S32. Reinforcement: The security filter element after structural restoration is reinforced with a skeleton reinforcement technique, and the reinforcement is located at the skeleton deformation position of the security filter element. S33. Sealing: Replace the sealing structure of the security filter element after structural restoration.

6. The method for recycling and reusing the security filter element as described in claim 1, characterized in that, The step preceding S10 includes: S00. Pre-treatment: Inspect the recovered security filter cartridges, remove obviously damaged ones, and record relevant information about the security filter cartridges. The relevant information includes the model of the security filter element, the service life of the security filter element, and the filter medium of the security filter element.

7. The method for recycling and reusing the security filter element as described in claim 6, characterized in that, The S00 process also includes surface rinsing of the recovered security filter element.

8. The method for recycling and reusing the security filter element as described in claim 1, characterized in that, The step following S30 is as follows: S40. Performance verification: The regenerated security filter element is subjected to quality testing. The security filter element that passes the test is marked with the number of regenerations and performance parameters and enters the reuse stage. The security filter element that fails the test enters the material recycling process. The quality testing includes at least one of the following: filtration accuracy test, flux test, pressure resistance test, and sealing test.

9. The method for recycling and reusing the security filter element as described in claim 8, characterized in that, The step following S40 is as follows: S50. Drying: The qualified security filter element is dried. S60. Packaging: Package the dried security filter element and attach regeneration information for the security filter element.

10. The method for recycling and reusing the security filter element as described in claim 9, characterized in that, In step S50, the security filter element is dehumidified and dried under conditions below the temperature tolerance threshold of the security filter element. In step S60, a composite barrier membrane material is used to seal and package the security filter element.

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