Efficient total phosphorus filtering device and control method thereof
By designing a gradient pleated filter element and controlling the flow rate, the problem of unsatisfactory treatment effect of chemical precipitation of phosphorus-containing wastewater was solved, achieving a high-efficiency, green and self-cleaning total phosphorus filtration effect.
Patent Information
- Application Number
- CN202511296220.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-11
- Publication Date
- 2025-11-18
AI Technical Summary
In existing technologies, chemical precipitation methods for treating phosphorus-containing wastewater cannot achieve green water treatment and the phosphorus removal effect is not ideal.
The filter element consists of a PP coarse fiber filter media, a middle PP fine fiber gradient layer, and an inner PP ultra-fine fiber dense layer. It achieves efficient interception of colloidal phosphorus through a gradient folding structure and flow rate control, and performs self-cleaning by backwashing and air rinsing.
It achieves a colloidal phosphorus retention rate of over 90% without chemical additives, pioneering a new path for green water treatment and improving filtration efficiency and self-cleaning capabilities.
Smart Images
Figure CN120960874A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of wastewater / black and odorous water treatment technology, and in particular to a high-efficiency total phosphorus filtration device and its control method. Background Technology
[0002] Phosphorus pollution can cause varying degrees of harm to humans, marine life, soil, and water bodies. When the total phosphorus concentration in stagnant water exceeds 86 ug / L, the water body is considered eutrophic and polluted. Eutrophication will cause red tides, massive algal blooms, and the death of fish and shrimp, among other malignant phenomena.
[0003] Currently, the most commonly used method for treating phosphorus-containing wastewater is chemical precipitation. This typically involves adjusting the pH of the wastewater with lime / alkali, and then adding flocculants for neutralization, coagulation, flocculation, and sedimentation. However, this method uses chemical agents and cannot achieve green water treatment. Furthermore, the treated wastewater does not achieve the desired phosphorus removal effect. Summary of the Invention
[0004] The purpose of this invention is to solve the above-mentioned problems by providing a high-efficiency total phosphorus filtration device and its control method.
[0005] The technical solution of this application is implemented as follows: This invention provides a high-efficiency total phosphorus filtration device, comprising: The filter element comprises, in sequence, an outer layer of coarse PP filter media, a middle layer of fine PP gradient layer, and an inner layer of ultrafine PP dense layer; wherein, the outer layer of coarse PP filter media has a porosity of 80-90% and a pore size of 0.9-1.0 μm; the middle layer of fine PP gradient layer has a porosity of 78%-65% and a pore size of 0.8-0.5 μm; and the inner layer of ultrafine PP dense layer has a porosity of 40-60% and a pore size of 0.22-0.4 μm.
[0006] As a further improvement, the outer PP coarse fiber filter material, the middle PP fine fiber gradient layer, and the inner PP ultrafine fiber dense layer are all folded structures, and the folding height from the outer layer to the inner layer is the same, so as to ensure the throughput and flow rate of the compression channel, while enhancing inertial collision.
[0007] As a further improvement, the height of the outer PP coarse fiber filter material, the middle PP fine fiber gradient layer, and the inner PP ultrafine fiber dense layer is 8.0-30.0 mm, depending on the dimensions of the inner and outer skeletons.
[0008] As a further improvement, the number of folds is consistent from the outer layer to the inner layer to ensure the effective contact area per unit volume.
[0009] As a further improvement, the outer, middle, and inner fiber filter materials have 100 to 175 folds.
[0010] As a further improvement, the flow velocity decreases from the outer layer to the inner layer.
[0011] As a further improvement, the outer layer of PP coarse fiber filter material has wide flow channels, the middle layer of PP fine fiber gradient layer has variable diameter flow channels, and the inner layer of PP ultrafine fiber dense layer has narrow flow channels.
[0012] The present invention further provides a control method for the above-mentioned high-efficiency total phosphorus filtration device, comprising the following steps: Wastewater / black and odorous water is controlled to flow through the outer layer of PP coarse fiber filter media, the middle layer of PP fine fiber gradient layer, and the inner layer of PP ultrafine fiber dense layer at a predetermined flow rate. Specifically, the wastewater / black and odorous water is controlled to flow through the outer layer of PP coarse fiber filter media at a high speed of 0.45~0.55m / s; through the middle layer of PP fine fiber gradient layer at a flow rate of 0.25~0.35m / s; and through the inner layer of PP ultrafine fiber dense layer at a flow rate of 0.05~0.15m / s.
[0013] As a further improvement, the control method of the present invention further includes: Self-cleaning is achieved through backwashing and air flushing.
[0014] The advantages or beneficial effects of the above technical solutions include at least the following: The gradient pleated filter element provided by this invention achieves a colloidal phosphorus rejection rate of >90% (0.22-1μm) through purely physical structural innovation without the use of chemical modification. Furthermore, the high-efficiency total phosphorus filtration device provided by this invention achieves zero chemical addition, pioneering a new path for green water treatment. Finally, the core of this invention lies in its groundbreaking integration of fluid mechanics and precision fiber manufacturing, proving that structural design can replace material modification and opening up a completely new direction for filter element technology. Attached Figure Description
[0015] The accompanying drawings illustrate exemplary embodiments of the present application and, together with the description thereof, serve to explain the principles of the present application. These drawings are included to provide a further understanding of the present application and are incorporated in and constitute a part of this specification.
[0016] Figure 1 A schematic diagram of the filter element in the high-efficiency total phosphorus filtration device provided in an embodiment of the present invention is shown.
[0017] Figure 2 A schematic diagram of the structure of the high-efficiency total phosphorus filtration device provided in an embodiment of the present invention is shown. Detailed Implementation
[0018] Embodiments of this application will now be described in more detail with reference to the accompanying drawings. While some embodiments of this application are shown in the drawings, it should be understood that this application can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this application. It should be understood that the drawings and embodiments of this application are for illustrative purposes only and are not intended to limit the scope of protection of this application.
[0019] It should be noted that, where there is no conflict, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.
[0020] The names of the messages or information exchanged between multiple devices in the embodiments of this application are for illustrative purposes only and are not intended to limit the scope of these messages or information.
[0021] Reference Figure 1 This invention provides a high-efficiency total phosphorus filtration device, comprising: The filter element 100 comprises an outer layer of coarse PP filter material 11, a middle layer of fine PP gradient layer 12, and an inner layer of ultrafine PP dense layer 13 arranged sequentially; wherein, the outer layer of coarse PP filter material 11 has a porosity of 80-90% and a pore size of 0.9-1.0 μm; the middle layer of fine PP gradient layer has a porosity of 78%-65% and a pore size of 0.8-0.5 μm; and the inner layer of ultrafine PP dense layer 13 has a porosity of 40-60% and a pore size of 0.22-0.4 μm.
[0022] In other embodiments, the filter element 100 further includes an outer shell 10 and a central frame 14. The outer shell 10 has a plurality of inlets 101 evenly distributed on its surface, and the central frame 14 also has a plurality of outlet holes 141 on its surface, thus forming a filtration channel between the inlets 101 and the outlet holes 141. The outer PP coarse fiber filter material 11, the middle PP fine fiber gradient layer 12, and the inner PP ultrafine fiber dense layer 13 are sequentially arranged in the filtration channel. The central frame 14 also includes a second outlet (not shown in the figure), which communicates with the outlet holes 141 for overall water discharge from the filter element 100.
[0023] Preferably, the outer PP coarse fiber filter material 11 has a porosity of 84-86% and a pore size of 0.9-1.0 μm. In one embodiment, the outer PP coarse fiber filter material 11 has a porosity of approximately 85% and a pore size of approximately 1.0 μm. The outer PP coarse fiber filter material 11 is used to retain suspended matter with a particle size greater than or equal to 1 μm to form a pre-filtration layer.
[0024] The intermediate PP fine fiber gradient layer 12 is used to deeply retain colloidal phosphorus of 0.5-1 μm. In other embodiments, the intermediate PP fine fiber gradient layer 12 can be formed in multiple layers to create a multi-layered gradient pore size; for example, it can form a four-layer structure with pore sizes of 0.8 μm, 0.7 μm, 0.6 μm, and 0.5 μm respectively. In one embodiment, the pore size of the intermediate PP fine fiber gradient layer 12 is approximately 0.5 μm.
[0025] The inner PP microfiber densification layer 13 is used for fine filtration barrier to intercept 0.22-0.5μm colloids. In other embodiments, the inner PP microfiber densification layer 13 can be formed in multiple layers to create a multi-layered gradient pore size; for example, it can form a four-layer structure with pore sizes of 0.5μm, 0.4μm, 0.3μm, and 0.22μm respectively. In one embodiment, the pore size of the inner PP microfiber densification layer 13 is approximately 0.22μm.
[0026] As a further improvement, the outer PP coarse fiber filter material 11, the middle PP fine fiber gradient layer 12, and the inner PP ultrafine fiber densified layer 13 are all folded structures, and the folding height from the outer layer to the inner layer is the same, so as to ensure the throughput and flow rate of the compression channel, while enhancing inertial collision.
[0027] Preferably, as a further improvement, the height of the outer PP coarse fiber filter material 11, the middle PP fine fiber gradient layer 12, and the inner PP ultrafine fiber dense layer 13 is 8.0-30.0 mm, depending on the dimensions of the inner and outer skeletons.
[0028] As a further improvement, in the filter element 100, the number of folds from the outer layer to the inner layer is consistent to ensure the effective contact area per unit volume.
[0029] As a further improvement, the outer PP coarse fiber filter material 11 has 100-175 folds; the middle PP fine fiber gradient layer 12 has 100-175 folds; and the inner PP ultrafine fiber dense layer 13 has 100-175 folds. Preferably, the outer PP coarse fiber filter material 11 has 110-130 folds; the middle PP fine fiber gradient layer 12 has 110-130 folds; and the inner PP ultrafine fiber dense layer 13 has 110-130 folds. In one embodiment, the outer PP coarse fiber filter material 11 has 120 folds; the middle PP fine fiber gradient layer 12 has 120 folds; and the inner PP ultrafine fiber dense layer 13 has 120 folds, so that the effective area per unit volume can remain consistent, that is, the effective area per unit volume can reach 0.9m². 2 / piece (10-inch filter cartridge), 1.8m 2 / piece (20-inch filter cartridge). Experiments have shown that when the number of folds in each layer decreases, the effective area is lower; while when there are too many folds in each layer, it will greatly increase the resistance of water flow, reduce turbulence and inertial collisions, thus significantly reducing the filtration efficiency.
[0030] As a further improvement, in other embodiments, a laser can be used to ablate annular lattice microgrooves (groove width 40~60μm, spacing 200~500μm) in the inner PP microfiber densification layer 13 to form turbulence triggering points and increase the probability of inertial collisions.
[0031] As a further improvement, preferably, the flow rate decreases from the outer layer to the inner layer.
[0032] As a further improvement, the outer PP coarse fiber filter material 11 has wide flow channels, the middle PP fine fiber gradient layer 12 has variable diameter flow channels, and the inner PP ultrafine fiber dense layer 13 has narrow flow channels.
[0033] This invention, taking a 10-inch filter cartridge as an example, further provides a control method for the above-mentioned high-efficiency total phosphorus filtration device, including the following steps: Wastewater is controlled to flow through the outer PP coarse fiber filter material 11, the middle PP fine fiber gradient layer 12, and the inner PP ultrafine fiber dense layer 13 at a predetermined flow rate. For example, with a 10-inch filter cartridge, the wastewater is controlled to flow through the outer PP coarse fiber filter material 11 at a high speed of 0.5 m / s, through the middle PP fine fiber gradient layer 12 at a high speed of 0.3 m / s, and through the inner PP ultrafine fiber dense layer 13 at a flow rate of 0.1 m / s.
[0034] As a further improvement, the control method for the high-efficiency total phosphorus filtration device provided by the present invention further includes: Self-cleaning is achieved through backwashing and air flushing.
[0035] Example 1: A high-efficiency total phosphorus filtration device includes: a filter element 100, comprising an outer layer of coarse PP filter media 11, a middle layer of fine PP filter media 12, and an inner layer of ultrafine PP filter media 13 arranged sequentially; wherein the outer layer of coarse PP filter media 11 has a porosity of 85% and a pore size of 1.0 μm; the middle layer of fine PP filter media 12 has a porosity of 65% and a pore size of 0.5 μm; the inner layer of ultrafine PP filter media 13 has a porosity of 40% and a pore size of 0.22 μm; ...0.22 μm; the outer layer of coarse PP filter media 12 has a porosity of 65% and a pore size of 0.5 μm; the inner layer of ultrafine PP filter media 12 has a porosity of 40% and a pore size of 0.22 μm; the outer layer of coarse PP filter media 12 has a porosity of 65% and a pore size of 0.5 μm; the inner layer of ultrafine PP filter media 12 has a porosity of 40% and a pore size of 0.22 μm; the outer layer of coarse PP filter media 12 has a porosity of 65% and a pore size of 0.5 μm; The outer coarse fiber filter material 11, the middle PP fine fiber gradient layer 12, and the inner PP ultrafine fiber dense layer 13 all have a folded structure. The height of the outer PP coarse fiber filter material 11, the middle PP fine fiber gradient layer 12, and the inner PP ultrafine fiber dense layer 13 is 20mm. The outer PP coarse fiber filter material 11 has 120 folds; the middle PP fine fiber gradient layer 12 has 120 folds; and the inner PP ultrafine fiber dense layer 13 has 120 folds. Testing shows that the effective area per unit volume of the filter element 100 can reach 0.9m². 2 / 10-inch filter cartridge, 1.8m 2 / 20-inch filter cartridge.
[0036] During filtration testing, taking a 10-inch filter cartridge as an example, wastewater was controlled to flow at a high speed of 0.5 m / s through the outer PP coarse fiber filter media 11, at a high speed of 0.3 m / s through the middle PP fine fiber gradient layer 12, and at a flow rate of 0.1 m / s through the inner PP ultrafine fiber dense layer 13. Tests showed that it could achieve a 94% rejection rate for colloidal phosphorus particles with a diameter of 0.22-1 μm. From the above data, it can be seen that the folded structure generates more turbulence and inertial collisions on the filter media surface, especially for larger particles (such as colloidal phosphorus around 1 μm), where inertial collisions are one of the main rejection mechanisms.
[0037] Example 2: The process is basically the same as in Example 1, except that the outer PP coarse fiber filter material 11, the middle PP fine fiber gradient layer 12, and the inner PP ultrafine fiber densified layer 13 are all folded 100 times.
[0038] During filtration testing, taking a 10-inch filter cartridge as an example, wastewater was controlled to flow at a high speed of 0.5 m / s through the outer PP coarse fiber filter media 11, and at a flow rate of 0.12 m / s through the inner PP ultrafine fiber dense layer 13. Tests showed that it could achieve a retention rate of approximately 90% for colloidal phosphorus particles with a diameter of 0.22-1 μm.
[0039] Comparative Example 1: The method is basically the same as in Example 1, except that the outer PP coarse fiber filter material 11, the middle PP fine fiber gradient layer 12, and the inner PP ultrafine fiber densified layer 13 all have 80 folds.
[0040] During filtration testing, taking a 10-inch filter cartridge as an example, wastewater was controlled to flow at a high speed of 0.5 m / s through the outer PP coarse fiber filter media 11 and at a flow rate of 0.14 m / s through the inner PP ultrafine fiber dense layer 13. The test results showed that its retention rate for colloidal phosphorus particles with a diameter of 0.22-1 μm was only about 76%.
[0041] As can be seen from Comparative Example 1 and Examples 1 and 2 above, as the number of folded layers increases, the turbulence and inertial collisions increase, thereby greatly improving the retention rate.
[0042] Example 3: The process is basically the same as in Example 1, except that the outer PP coarse fiber filter material 11, the middle PP fine fiber gradient layer 12, and the inner PP ultrafine fiber densified layer 13 all have 150 folds.
[0043] During filtration testing, taking a 10-inch filter cartridge as an example, wastewater was controlled to flow at a high speed of 0.5 m / s through the outer PP coarse fiber filter media 11, and at a flow rate of 0.08 m / s through the inner PP ultrafine fiber dense layer 13. Tests showed that it could achieve a retention rate of approximately 92% for colloidal phosphorus particles with a diameter of 0.22-1 μm.
[0044] Example 4: The process is basically the same as in Example 1, except that the outer PP coarse fiber filter material 11, the middle PP fine fiber gradient layer 12, and the inner PP ultrafine fiber densified layer 13 all have 170 folds.
[0045] During filtration testing, taking a 10-inch filter cartridge as an example, wastewater was controlled to flow at a high speed of 0.5 m / s through the outer PP coarse fiber filter media 11, and at a flow rate of 0.05 m / s through the inner PP ultrafine fiber dense layer 13. Tests showed that it could achieve a retention rate of approximately 90% for colloidal phosphorus particles with a diameter of 0.22-1 μm.
[0046] Comparative Example 2: The method is basically the same as in Example 1, except that the outer PP coarse fiber filter material 11, the middle PP fine fiber gradient layer 12, and the inner PP ultrafine fiber densified layer 13 all have 185 folds.
[0047] During filtration testing, taking a 10-inch filter cartridge as an example, wastewater was controlled to flow at a high speed of 0.5 m / s through the outer PP coarse fiber filter media 11 and at a flow rate of 0.04 m / s through the inner PP ultrafine fiber dense layer 13. The test results showed that its retention rate for colloidal phosphorus particles with a diameter of 0.22-1 μm was only about 84%.
[0048] The data above shows that as the number of folds increases further, the flow channels inside the filter element become too narrow, the water flow resistance increases significantly, and the turbulence and inertial collisions decrease significantly, which in turn leads to a certain decrease in the retention rate.
[0049] Please see Figure 2 As shown, in other embodiments, the high-efficiency total phosphorus filtration device includes at least two filter elements 100 arranged in parallel.
[0050] In other embodiments, the high-efficiency total phosphorus filtration device further includes a raw water tank 200, which is connected to the raw water inlet of the filter element 100 via a pump 300, and the raw water inlet is connected to the inlet 101. The high-efficiency total phosphorus filtration device also includes a backwash fan 400, which is connected to a second outlet for air-flushing backwashing. The high-efficiency total phosphorus filtration device further includes a backwash pump 600 and a backwash water phase 500, which is connected to the second outlet via the backwash pump 600 for water-flushing backwashing. The high-efficiency total phosphorus filtration device also includes a sludge treatment unit 700, which is connected to a sludge outlet located at the bottom of the filter element 100, and is used to receive sludge and perform sludge concentration and dewatering during backwashing.
[0051] The steps for achieving self-cleaning through backwashing and air rinsing specifically include: When the filter reaches the automatic backwashing condition, close the inlet and outlet valves of the filter element 100, then open the backwash fan 400 and its corresponding pipeline valves for air flushing. Set the air flushing time. When the air flushing time is reached, close the backwash fan 400 and simultaneously open the backwash pump 600 and its corresponding valves. After the valves are fully open, perform water flushing. Set the water flushing time. When the water flushing time is reached, stop the backwash pump 600. After the automatic backwashing is completed, the filter element 100 enters the automatic filtration control program. Specifically, during air flushing, preferably, the filter element's natural frequency (42 Hz measured for a 10-inch filter element) is used as the period, and air pulses of 0.4 MPa --> 0.1 MPa are superimposed to form a resonant stripping of the sludge layer. The filter element and end caps form an elastomer. Actual measurements show it resonates around 42 Hz. During backwashing, instead of continuous air release, it repeatedly "taps" at a frequency of 42 times per second: 0.025s for 0.4MPa high pressure --> 0.025s for 0.1MPa low pressure, one cycle being 0.05s, which corresponds exactly to 42Hz. Because the tapping frequency equals the filter element's natural frequency, the minute vibrations are amplified, causing shear fatigue between the mud layer and fibers, loosening the dust like shaking a blanket, which is then carried away by the water flow.
[0052] The automatic backwashing program for the filter can only be performed when the filter backwash tank is in the middle position.
[0053] Those skilled in the art should understand that the above embodiments are merely for illustrative purposes and are not intended to limit the scope of this application. Those skilled in the art can make other changes or modifications based on the above disclosure, and these changes or modifications still fall within the scope of this application.
Claims
1. A high-efficiency total phosphorus filtration device, characterized in that, include: The filter element comprises, in sequence, an outer layer of coarse PP filter media, a middle layer of fine PP gradient layer, and an inner layer of ultrafine PP dense layer; wherein, the outer layer of coarse PP filter media has a porosity of 80-90% and a pore size of 0.9-1.0 μm; the middle layer of fine PP gradient layer has a porosity of 78%-65% and a pore size of 0.8-0.5 μm; and the inner layer of ultrafine PP dense layer has a porosity of 40-60% and a pore size of 0.22-0.4 μm.
2. The high-efficiency total phosphorus filtration device according to claim 1, characterized in that, The outer PP coarse fiber filter material, the middle PP fine fiber gradient layer, and the inner PP ultrafine fiber dense layer are all folded structures, and the folding height from the outer layer to the inner layer is the same to ensure the throughput and flow rate of the compression channel, while enhancing inertial collision.
3. The high-efficiency total phosphorus filtration device according to claim 2, characterized in that, Based on the dimensions of the inner and outer skeletons, the heights of the outer PP coarse fiber filter material, the middle PP fine fiber gradient layer, and the inner PP ultrafine fiber dense layer are 8.0-30.0 mm.
4. The high-efficiency total phosphorus filtration device according to claim 2, characterized in that, The number of folds is consistent from the outer layer to the inner layer to ensure the effective contact area per unit volume.
5. The high-efficiency total phosphorus filtration device according to claim 4, characterized in that, The outer, middle, and inner fiber filter media have 100 to 175 folds.
6. The high-efficiency total phosphorus filtration device according to claim 2, characterized in that, The flow velocity decreases from the outer layer to the inner layer.
7. The high-efficiency total phosphorus filtration device according to claim 6, characterized in that, The outer layer of PP coarse fiber filter material has wide flow channels, the middle layer of PP fine fiber gradient layer has variable diameter flow channels, and the inner layer of PP ultrafine fiber dense layer has narrow flow channels.
8. A control method for a high-efficiency total phosphorus filtration device according to any one of claims 1-7, characterized in that, Includes the following steps: Wastewater / black and odorous water is controlled to flow through the outer layer of PP coarse fiber filter material, the middle layer of PP fine fiber gradient layer and the inner layer of PP ultrafine fiber dense layer at a predetermined flow rate, wherein the wastewater / black and odorous water is controlled to flow through the outer layer of PP coarse fiber filter material at a high speed of 0.45~0.55m / s. The material flows through the intermediate PP fine fiber gradient layer at a flow rate of 0.25~0.35 m / s and through the inner PP ultrafine fiber dense layer at a flow rate of 0.05~0.15 m / s.
9. The control method for the high-efficiency total phosphorus filtration device according to claim 8, characterized in that, It also includes: Self-cleaning is achieved through backwashing and air flushing.