CN107051016B - Composite modified gas-liquid coalescing filter - Google Patents

Abstract

The application provides a composite modified gas-liquid coalescing filter, which comprises: a cylindrical skeleton; the first filter layer comprises a first nanofiber modified layer and a first micrometer fiber modified layer, the head end of the first nanofiber modified layer is wound outside the cylindrical framework, the head end edge of the first micrometer fiber modified layer is in seamless connection with the tail end edge of the first nanofiber modified layer, and the first micrometer fiber modified layer is wound outside the first nanofiber modified layer; the second filter layer comprises a second nanofiber modified layer and a second micrometer fiber modified layer, the head end edge of the second nanofiber modified layer is in seamless connection with the tail end edge of the first micrometer fiber modified layer, the second nanofiber modified layer is wound on the outer side of the first micrometer fiber modified layer, the head end edge of the second micrometer fiber modified layer is in seamless connection with the tail end edge of the second nanofiber modified layer, and the second micrometer fiber modified layer is wound on the outer side of the second nanofiber modified layer. The application can prevent the phenomenon of secondary entrainment.

Description

Composite modified gas-liquid coalescing filter

Technical field

The invention relates to the field of gas-liquid filtration devices, specifically a composite modified gas-liquid coalescing filter.

Background technique

In fields such as natural gas, coal bed methane and compressed air, liquid droplets of different sizes are usually entrained in the gas, thus affecting the cleanliness of the gas and the operational safety of related instruments and equipment. Generally, filtration and separation equipment such as gravity separator, inertial separator, cyclone separator or gas-liquid coalescing filter are used for gas-liquid separation. At present, for droplets with smaller particle sizes such as microns and sub-microns, gas-liquid coalescing filters are mostly used. The gas-liquid coalescing filter is composed of an inner skeleton and an outer layer of fiber filter material. Inorganic fibers such as metal fibers and glass fibers, and organic fiber materials such as polyester fibers and polypropylene fibers are commonly used gas-liquid coalescing filter materials. Most of them are lipophilic and generally require surface modification methods for treatment. Commonly used surface modification methods include solution dipping and plasma methods. The solution impregnation method has shortcomings such as a large amount of solvent waste, complex treatment processes, and uneven treatment effects. The plasma method plasmaizes the corresponding process gas, and the generated plasma chemically reacts with the surface of the object to achieve surface cleaning, activation or modification. Generally divided into normal pressure plasma and low pressure plasma technology, the latter can form a vacuum environment in the processing chamber, allowing the plasma to enter any surface inside the filter material, thereby achieving a very uniform and comprehensive surface treatment. For oleophilic filter materials, during the filtration process, a liquid film is easily formed on the air outlet surface. The liquid film is ruptured under the action of air flow, causing secondary entrainment of micron-sized droplets. When oleophobic filter materials are selected, It can reduce the occurrence of secondary entrainment, thereby helping to improve filtration efficiency.

With the development of instruments and equipment towards high precision and the transformation of air quality control from PM10 to PM2.5, the filtration efficiency of traditional gas-liquid coalescing filters for sub-micron droplets (especially droplets in the most easily penetrating particle size range) is relatively low. Low and unable to meet the corresponding technical or environmental requirements. Nanofibers can effectively capture droplets within this range due to their smaller fiber diameter and pore size. However, their lipophilic characteristics lead to the easy formation of liquid films during use and a large pressure drop, and their strength Weak characteristics make it difficult to be directly applied in the field of gas-liquid coalescing filtration.

The Chinese invention patent with publication number CN 104307288 A discloses a high-efficiency cyclone coalescing gas-liquid separator. The separator mainly includes a container shell and a cyclone centrifugal separation section and a rectifier set from bottom to top. The liquid plate, the nanofiber coalescence separation section, the spiral separation section and other gradient components; the container shell is provided with a mixed gas inlet, a purified gas outlet and a liquid phase outlet. This invention effectively combines three separation methods including gravity sedimentation, centrifugal separation and coalescence separation with surface modification technology. It has high separation efficiency and processing capabilities and can effectively prevent secondary entrainment. Disadvantages of this invention patent: This invention uses a swirling method to reduce secondary entrainment of droplets. The overall structure is complex and the area is too large, which is not conducive to installation and operation.

The Chinese invention patent with the publication number CN 105392544 A discloses a gradient nanofiber filter medium, which is formed of multiple layers of media materials. The multi-layer media materials include nanofiber media layers, wherein the above-mentioned multiple layers are stacked on each other. combine or otherwise compound with each other. The composite filter medium may include at least one nanofiber modified layer, the at least one nanofiber modified layer including a polymer media material with a geometric mean fiber diameter of about 100 nm to 1 μm and a plurality of fibers, the plurality of fibers configured as follows Gradient, the ratio of the geometric mean diameter of each fiber at the upstream surface of the above-mentioned nanofiber modified layer to the geometric mean diameter of each fiber at the downstream surface of the above-mentioned nanofiber modified layer is about 1.1 to 2.8, preferably about 1.2 to 2.4. Disadvantages of this invention patent: This composite filter medium directly combines nanofiber modified layers of different diameters and is mainly used for liquid-solid filtration or liquid-liquid coalescing filtration. However, the thickness of the nanofiber modified layer (at least 40 μm) is too large. There is no drainage channel inside the filter medium, and liquid can easily remain inside the medium, causing excessive pressure drop and secondary entrainment. It is not suitable for the field of gas-liquid coalescing filtration.

Contents of the invention

The invention provides a composite modified gas-liquid coalescing filter to achieve the purpose of reducing secondary entrainment of liquid droplets.

The technical solution adopted by the present invention to solve the technical problems is: a composite modified gas-liquid coalescing filter. The composite modified gas-liquid coalescing filter includes: a cylindrical skeleton; a first filter layer including a first nanofiber The modified layer and the first micron fiber modified layer, the first nanofiber modified layer and the first micron fiber modified layer are respectively wound around the cylindrical frame for at least one week, and the first end of the first nanofiber modified layer is wound around the cylinder. Outside the shaped skeleton, the first edge of the first micron fiber modified layer is seamlessly connected to the end edge of the first nanofiber modified layer, and the first micron fiber modified layer is wound around the outside of the first nanofiber modified layer; The second filter layer includes a second nanofiber modified layer and a second micron fiber modified layer. The second nanofiber modified layer and the second micron fiber modified layer are respectively arranged around the cylindrical frame for at least one week. The second nanofiber The first edge of the modified layer is seamlessly connected to the end edge of the first micron fiber modified layer, and the second nanofiber modified layer is wound around the outside of the first micron fiber modified layer. The first end edge is seamlessly connected to the end edge of the second nanofiber modified layer, and the second micron fiber modified layer is wound around the outside of the second nanofiber modified layer.

Further, the composite modified gas-liquid coalescing filter also includes a third filter layer. The third filter layer includes a third nanofiber modified layer and a third micron fiber modified layer. The head end of the third nanofiber modified layer The edge is seamlessly connected to the end edge of the second micron fiber modified layer, and the third micron fiber modified layer is wound around the outside of the second micron fiber modified layer, and the first edge of the third micron fiber modified layer is connected to the third The end edges of the nanofiber modified layer are seamlessly connected, and the third micron fiber modified layer is wound around the outside of the third nanofiber modified layer.

Further, along the radial direction of the cylindrical skeleton from the inside to the outside, the pore sizes of the first nanofiber modified layer, the second nanofiber modified layer and the third nanofiber modified layer gradually increase; the first micron fiber modified layer The pore sizes of the elastic layer, the second micron fiber modified layer and the third micron fiber modified layer gradually increase.

Further, the ratio of the pore diameter of the first nanofiber modified layer to the pore diameter of the second nanofiber modified layer is 0.3 to 0.9, and the ratio of the pore diameter of the first micron fiber modified layer to the pore diameter of the second micron fiber modified layer is 0.4. to 0.9.

Further, the ratio of the pore diameter of the second nanofiber modified layer to the pore diameter of the third nanofiber modified layer is 0.3 to 0.9, and the ratio of the pore diameter of the second micron fiber modified layer to the pore diameter of the third micron fiber modified layer is 0.4. to 0.9.

Further, the thickness of the first nanofiber modified layer, the second nanofiber modified layer and the third nanofiber modified layer is 5 microns to 25 microns; the first micron fiber modified layer, the second micron fiber modified layer The thickness of both the first layer and the third micron fiber modified layer is 0.1mm to 3mm.

Further, the inside of the first end of the first micron fiber modified layer is bonded to the outside of the first nanofiber modified layer through the first glue layer, and the inside of the end of the first micron fiber modified layer is bonded to the first through the second glue layer. The end of the nanofiber modified layer is bonded to the outside, and the inside of the first end of the second nanofiber modified layer is bonded to the outside of the first micron fiber modified layer through the third glue layer.

Further, the first glue layer, the second glue layer and the third glue layer are each composed of a plurality of glue spraying points, and the plurality of glue spraying points of the first glue layer and the plurality of glue spraying points of the third glue layer are arranged along the cylindrical shape. The axial offset setting of the skeleton.

Further, the composite modified gas-liquid coalescing filter also includes a liquid drainage layer, the first edge of the liquid drainage layer is seamlessly connected to the end edge of the second micron fiber modified layer.

Further, the pore diameter of the liquid drainage layer is greater than or equal to 70 μm, and the thickness of the liquid drainage layer is 0.1mm-3mm.

Further, the height direction of the first filter layer and the height direction of the second filter layer are both arranged along the axial direction of the cylindrical frame, and the height of the first filter layer and the height of the second filter layer 30 are consistent with the axial height of the cylindrical frame. same.

The beneficial effect of the present invention is that the embodiments of the present invention can ensure a lower pressure drop and at the same time have a higher sensitivity to submicron droplets (especially droplets in the most easily penetrating particle size range) and micron-sized droplets. The filtration efficiency can effectively reduce the secondary entrainment of droplets.

Description of the drawings

The description and drawings that constitute a part of this application are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the attached picture:

Figure 1 is a front structural cross-sectional view of an embodiment of the composite modified gas-liquid coalescing filter of the present invention;

Figure 2 is a top structural cross-sectional view of an embodiment of the composite modified gas-liquid coalescing filter of the present invention;

Figure 3 is a schematic diagram of misplaced glue spraying in an embodiment of the composite modified gas-liquid coalescing filter of the present invention;

Figure 4 is an experimental data diagram of the liquid accumulation amount and pressure drop of the embodiment of the composite modified gas-liquid coalescing filter of the present invention;

Figure 5 is an experimental data chart showing the particle size and filtration efficiency of the embodiment of the composite modified gas-liquid coalescing filter of the present invention.

Reference numbers in the figure: 10. Cylindrical skeleton; 20. First filter layer; 21. First nanofiber modified layer; 22. First micron fiber modified layer; 30. Second filter layer; 31. Second Nanofiber modified layer; 32. Second micron fiber modified layer; 40. Third filter layer; 41. Third nanofiber modified layer; 42. Third micron fiber modified layer; 50. Liquid drainage layer; 61 , the first glue spraying point; 62. the third glue spraying point.

Detailed ways

It should be noted that, as long as there is no conflict, the embodiments and features in the embodiments of this application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and embodiments.

As shown in Figures 1 and 2, embodiments of the present invention provide a composite modified gas-liquid coalescing filter. The composite modified gas-liquid coalescing filter includes a cylindrical frame 10, a first filter layer 20 and a second filter layer. Filter layer 30. The first filter layer 20 includes a first nanofiber modified layer 21 and a first micron fiber modified layer 22. The first nanofiber modified layer 21 and the first micron fiber modified layer 22 are arranged around the cylindrical frame 10 at least once, The first end of the first nanofiber modified layer 21 is wound outside the cylindrical frame 10, and the first end edge of the first micron fiber modified layer 22 is seamlessly connected with the end edge of the first nanofiber modified layer 21. The first The microfiber modified layer 22 is wound around the outside of the first nanofiber modified layer 21 . The second filter layer 30 includes a second nanofiber modified layer 31 and a second micron fiber modified layer 32. The second nanofiber modified layer 31 and the second micron fiber modified layer 32 surround the cylindrical frame 10 at least once. The first edge of the second nanofiber modified layer 31 is seamlessly connected to the end edge of the first micron fiber modified layer 22. The first nanofiber modified layer 32 is wound around the outside of the first micron fiber modified layer 22. The first edge of the two-micron fiber modified layer 32 is seamlessly connected to the end edge of the second nanofiber modified layer 31 , and the second micron fiber modified layer 32 is wound around the outside of the second nanofiber modified layer 31 . Among them, the cylindrical frame 10 can be made of metal or non-metallic materials such as polypropylene, which is used to support the outer filter material. The airflow flows out radially from the inside of the cylindrical frame 10 . The cylindrical frame 10 is surrounded by hollow materials such as hollow metal mesh or polypropylene. The above-mentioned hollows are used to form circulation holes for gas flow on the side walls of the cylindrical frame 10. The gas flows from the upper end or the lower end of the cylindrical frame 10. Enter.

Taking the first nanofiber modified layer 21 and the first micron fiber modified layer 22 as an example, the above-mentioned seamless connection refers to the end edge of the first nanofiber modified layer 21 and the first micron fiber modified layer 22. The first edges are seamlessly connected (no overlap) and can be connected by pasting, sewing or other processing methods. Of course, it is also within the scope of the present invention to seamlessly connect the end edge of the first nanofiber modified layer 21 and the first end edge of the first microfiber modified layer 22 without fixing.

Embodiments of the present invention can achieve high filtration efficiency for both sub-micron droplets (especially droplets in the most easily penetrating particle size range) and micron-sized droplets while ensuring a lower pressure drop, and can effectively reduce Secondary entrainment of small droplets.

Embodiments of the present invention are particularly suitable for working conditions with high filtration requirements for sub-micron droplets (especially droplets in the most easily penetrating particle size range). Through the alternating composite structure and the comprehensive utilization of nanofiber modified layers, the filtration efficiency is high. It has the advantage of large liquid drainage capacity of the micron fiber modified layer, realizing multi-stage coupling of droplet coalescence, growth and discharge, and the micron fiber modified layer in the composite structure also acts as a pre-filter.

It should be noted that the nanofibers are prepared by electrospinning technology (of course, the nanofiber preparation method described in the present invention is not limited to electrospinning technology, and can be prepared by stretching, melt-blown technology or other related methods). The solutes selected for the silk solution include polyacrylonitrile, polyimide, nylon, polystyrene, polyurethane, polyvinylidene fluoride and other organic materials, inorganic materials or organic/inorganic composite materials. Each of the nanofiber modified layers is treated with low-pressure plasma to make the fiber surface hydrophobic and oleophobic, effectively preventing trapped droplets from forming a dense liquid film inside the nanofiber modified layer and causing excessive pressure drop.

Micron fiber materials can be non-metallic fiber materials such as glass fiber, polyester fiber, polypropylene fiber, and metal fiber materials such as stainless steel. Each of the micron fiber modified layers can be treated with low-pressure plasma to make the fiber surface have super-hydrophilic and super-oleophilic properties, thereby realizing that the upstream (side close to the cylindrical skeleton 10) adjacent to each micron-sized fiber modified layer will be Upstream) The liquid droplets discharged from the nanofiber modified layer are quickly absorbed and discharged downward along the fiber surface, achieving timely drainage and ensuring a low filtration pressure drop.

It should be noted that the above-mentioned low-pressure plasma treatment refers to selecting a suitable process gas as the generation source, entering through the processing gas inlet, and the radio frequency power supply provides energy to the discharge electrode, and the process gas entering through the gas inlet is plasmaized. The filter material is placed above the filter material tray, and the generated plasma reacts chemically with the surface of the filter material, so that the filter material obtains the required super-hydrophilic, super-oleophilic or hydrophobic-oleophobic properties. During the treatment process, a vacuum pump is used to evacuate air to ensure that the inside of the chamber is in a low pressure state and the absolute pressure is lower than 10Pa, thereby ensuring that each pore of the filter material can be processed evenly. The hydrophobic and oleophobic modified process gas can be a gas containing low surface energy elements or a gas obtained by evaporating the corresponding liquid, and the super hydrophilic and super oleophilic modified process gas can be a gas containing hydrophilic functional groups Or a gas obtained by evaporation of the corresponding liquid. The preferred value of the surface modification treatment time of the nanofiber filter layer is 2-8 minutes, and the preferred value of the surface modification treatment time of the microfiber filter layer is 5-15 minutes.

Among them, the above-mentioned hydrophobic and oleophobic properties are tested in accordance with international standards. The oleophobic properties reach at least level 2 (ISO14419-2010, textile oleophobic test standard), and the hydrophobic properties reach 100 points (AATCC 22-2010, hydrophobic test standard). Super hydrophilic and super lipophilic properties mean that for distilled water and different oils used in the international standard ISO 14419-2010, when 5 μL of liquid is dropped on the material surface, the initial contact angle measured by the contact angle meter is close to 0° And the liquid disappears quickly within 1 second.

Preferably, the composite modified gas-liquid coalescing filter also includes a third filter layer 40. The third filter layer 40 includes a third nanofiber modified layer 41 and a third micron fiber modified layer 42. The third nanofiber modified layer The first edge of the layer 41 is seamlessly connected to the end edge of the second micron fiber modified layer 32. The third nanofiber modified layer 41 is wound around the outside of the second micron fiber modified layer 32. The third micron fiber modified layer The first edge of 42 is seamlessly connected to the end edge of the third nanofiber modified layer 41 , and the third micron fiber modified layer 42 is wound around the outside of the third nanofiber modified layer 41 . The third filter layer 40 is also treated with low-pressure plasma. In the embodiment of the present invention, the heights of the first filter layer 20 , the second filter layer 30 and the third filter layer 40 are all set along the vertical direction in FIG. 1 . The heights of the three filter layers 40 are all the same as the axial height of the cylindrical frame 10 . Wherein, the length of the above-mentioned first filter layer 20, the second filter layer 30 and the third filter layer 40 is the length along the circumferential direction of the cylindrical frame 10 in Figure 1, and the above-mentioned first filter layer 20, second filter layer 30 and The width of the third filter layer 40 is the height in the vertical direction mentioned above.

It should be noted that in the embodiment of the present invention, the above-mentioned filter layers (the first filter layer 20, the second filter layer 30 and the third filter layer 40) may be multiple layers, such as two to six layers. Under special working conditions, Can be higher than six floors. The arrangement of the above-mentioned multi-layer filter layers can be the same as that in the above embodiment. Moreover, the processing methods of the above-mentioned multi-layer filter layers are the same as the processing methods of the first filter layer 20 , the second filter layer 30 and the third filter layer 40 , for example, using low-pressure plasma processing.

In the embodiment of the present invention, the upper end of the cylindrical frame 10 is provided with an upper annular fixing part, and the lower end of the cylindrical frame 10 is provided with a lower annular fixing part. The above-mentioned upper annular fixing part and the lower annular fixing part are both fixed on the cylindrical frame 10. The upper ends of the above-mentioned plurality of filter layers in the vertical direction in Figure 1 are bonded to the upper annular fixing part of the cylindrical frame 10. The above-mentioned plurality of filters The lower ends of the layers in the vertical direction in Figure 1 are all bonded to the lower annular fixing part of the cylindrical frame 10.

Further, along the radial direction of the cylindrical frame 10 from the inside to the outside, the pore size of the nanofiber modified layer in each filter layer gradually increases, and the pore size of the micron fiber modified layer in each filter layer also gradually increases. big. Taking the three-layer filter layer as an example, along the radial direction of the cylindrical frame 10 from the inside to the outside, the pore sizes of the first nanofiber modified layer 21, the second nanofiber modified layer 31 and the third nanofiber modified layer 41 are Gradually increase; the pore diameters of the first micron fiber modified layer 22, the second micron fiber modified layer 32 and the third micron fiber modified layer 42 gradually increase.

Each nanofiber modified layer forms a pore diameter increasing structure between different layers from the inside to the outside to achieve a mutual match between fiber pore diameter and droplet size growth. According to the mechanism of droplet coalescence and growth, the pore diameter of each nanofiber modified layer is set to gradually increase. , ensuring high filtration efficiency while avoiding excessive pressure drop caused by completely using the smallest pore size nanofiber modified layer. Each micron fiber modified layer forms an increasing pore size structure between different layers from the inside to the outside to match the drainage channel and discharge droplet size to ensure effective drainage and reduce pressure drop and operating costs.

Specifically, the ratio of the pore diameter of the first nanofiber modified layer 21 to the pore diameter of the second nanofiber modified layer 31 is 0.3 to 0.9, wherein the ratio of the pore diameter of the first nanofiber modified layer 21 to the pore diameter of the second nanofiber modified layer 31 is 0.3 to 0.9. The preferred pore size ratio of 31 is 0.4 to 0.8. The ratio of the pore diameter of the first micron fiber modified layer 22 to the pore diameter of the second micron fiber modified layer 32 is 0.4 to 0.9, wherein the pore diameter of the first micron fiber modified layer 22 and the pore diameter of the second micron fiber modified layer 32 Preferred ratios are from 0.5 to 0.8. The ratio of the pore diameter of the second nanofiber modified layer 31 to the pore diameter of the third nanofiber modified layer 41 is 0.3 to 0.9, wherein the pore diameter of the second nanofiber modified layer 31 and the pore diameter of the third nanofiber modified layer 41 Preferred ratios are from 0.4 to 0.8. The ratio of the pore size of the second micron fiber modified layer 32 to the pore size of the third micron fiber modified layer 42 is 0.4 to 0.9, wherein the pore size of the second micron fiber modified layer 32 and the pore size of the third micron fiber modified layer 42 Preferred ratios are from 0.5 to 0.8.

In the embodiment of the present invention, the fiber diameter of the first nanofiber modified layer 21 ranges from 10 to 400 nm, and the thickness ranges from 5 to 25 μm. The fiber diameter of the second nanofiber modified layer 31 ranges from 100 to 600 nm, and the thickness ranges from 5 to 25 μm. The fiber diameter of the third nanofiber modified layer 41 ranges from 200 to 1000 nm, and the thickness ranges from 5 to 25 μm. When the number of nanofiber modified layers is more than three, the preferred fiber diameter range of the fourth layer and subsequent layers is in the range of 400-1000 nm, and the thickness range is in the range of 5-25 μm, and the fiber diameter of the latter layer must be no less than The fiber diameter of the previous layer.

The fiber diameter of the first micron fiber modified layer 22 ranges from 1 to 10 μm, and the thickness ranges from 0.1 to 3 mm. The fiber diameter of the second micron fiber modified layer 32 ranges from 5-20 μm, and the thickness ranges from 0.1-3mm. The fiber diameter of the third micron fiber modified layer 42 ranges from 10 to 30 μm, and the thickness ranges from 0.1 to 3 mm. When the number of the above-mentioned micron fiber modified layers is more than three, the preferred fiber diameter range of the fourth layer and subsequent layers is in the range of 10-30 μm, and the thickness range is 0.1-3mm, and the fiber diameter of the latter layer is ensured. smaller than the fiber diameter of the previous layer.

The embodiment of the present invention adopts a 4/3 turn winding method. The 4/3 turn winding method refers to winding 4/3 turns of nanofibers along the outer surface of the cylindrical skeleton 10 and continuing at the remaining 1/3 turns of nanofiber joining edges. Wrap the micron fiber around. Continue to wind 4/3 turns of the nanofiber modified layer at the edge of the micron fiber, and proceed in this manner alternately to form the structure shown in Figure 2, thereby realizing that the edge joints of adjacent nanofiber modified layers form a cycle with three layers, respectively. Staggered by 120° position. Preferably, according to the needs of different working conditions, the winding method can be from 6/5 turns to 3/2 turns.

In the embodiment of the present invention, each filter layer and between the nanofiber modified layer and the microfiber modified layer of the same filter layer are fixed by adhesion. Take the first filter layer and the second filter layer as an example. The first nanofiber modified layer 21 of the first filter layer is wound around the cylindrical frame 10 , and the inner end surface of the first nanofiber modified layer 21 is pasted on the outside of the first nanofiber modified layer 21 located on the inside. superior. The first end of the first micron fiber modified layer 22 is in contact with the end of the first nanofiber modified layer 21 , and the inner side of the first end of the first micron fiber modified layer 22 is pasted on the inner side of the first nanofiber modified layer 21 . on the fiber modified layer 21. The inner end of the first micron fiber modified layer 22 is pasted on the outer side of the first end of the first nanofiber modified layer 21 .

In the embodiment of the present invention, a misplaced glue spraying method is adopted. The misplaced glue spraying method is to atomize the adhesive with compressed air for glue spraying. The apparent pressure range of the compressed air for different adhesive settings is 0.1-0.8 bar. The apparent pressure is the optimal value and can be appropriately relaxed. The adhesive includes commonly used soluble glue and other glues that can be used for atomization. The glue spraying position is the inner position of the end of each filter material (except for the first nanofiber modified layer 21. The first nanofiber modified layer 21 is provided with a glue spraying position on the inner side of the end and not on the inner side of the head end). The optimal glue width is 6-15mm. The misalignment means that when both sides of the same material contain spray glue, for example, the positions of the glue spray points on both sides of the first end of the first micron fiber modified layer 22 mentioned above are staggered from each other along the axial direction of the cylindrical skeleton 10. As shown in Figure 3. This helps to increase gas or liquid flow channels and reduce resistance and operating costs. At the same time, it can help improve droplet interception efficiency. During the implementation process, the optimal distance between adjacent glue spraying points along the axial direction of the cylindrical frame 10 is 1-5 mm. Under appropriate conditions, glue can be sprayed between any fiber modified layers to prevent aging caused by fiber detachment or breakage, thereby further improving the overall strength of the filter. The air permeability test results show that the pressure difference of misplaced glue spray filter material increases by no more than 22% compared with ordinary filter materials. According to the filter material tensile test results, the transverse tear strength of misplaced glue spray filter material increases compared with ordinary filter materials. 55.8% larger, with better strength improvement.

Specifically, as shown in Figures 2 and 3, the inner end surface of the first nanofiber modified layer 21 is pasted on the outside of the first nanofiber modified layer 21 located in the inner ring through a fourth glue layer. The first end of the first micron fiber modified layer 22 is in contact with the end of the first nanofiber modified layer 21 , and the inner side of the first end of the first micron fiber modified layer 22 is connected to the first nanofiber modified layer 22 through the first glue layer. The outer side of the fiber modified layer 21 is bonded, the inner end of the first micron fiber modified layer 22 is bonded to the outer end of the first nanofiber modified layer 21 through the second glue layer, and the inner end of the second nanofiber modified layer 31 is bonded. The inside of the first end is bonded to the outside of the end of the first micron fiber modified layer 22 through the third glue layer. The inner side of the first end of the second micron fiber modified layer 32 is pasted on the second nanofiber modified layer 31 through the fifth glue layer. The first glue layer is composed of a plurality of first glue spraying dots 61, the second glue layer is composed of a plurality of second glue spraying dots, the third glue layer is composed of a plurality of third glue spraying dots 62, and the fourth glue layer is composed of a plurality of third glue spraying dots 62. The top layer is composed of a plurality of fourth glue spraying points, and the fifth glue layer is composed of a plurality of fifth glue spraying points. The plurality of first glue spraying points 61 and the plurality of third glue spraying points 62 are formed along the cylindrical frame 10 Axial offset setting. The plurality of second glue spraying points and the plurality of fourth glue spraying points are offset along the axial direction of the cylindrical frame 10 .

In the embodiment of the present invention, the above-mentioned positions that require misaligned glue spraying can be multiple in the present invention. For example, in Figure 3, there can be one misaligned glue spraying position every 120° along the circumferential direction. In the embodiment of the present invention, the head end and the tail end of each fiber modified layer are pasted to the outside of the adjacent fiber modified layer located in the inner ring. Whenever both sides of the same limited modified layer contain glue spraying points at the same position, the positions of the glue spraying points on both sides should be staggered from each other, and will not be described one by one here.

The composite modified gas-liquid coalescing filter also includes a liquid drainage layer 50. The head end of the liquid drainage layer 50 is seamlessly connected to the end of the second micron fiber modified layer 32. The end of the liquid drainage layer 50 is connected to the second micron fiber modified layer 32 on the inside. The fiber modified layer 32 is attached. In the embodiment of the present invention, when the inner filter layer has multiple layers, the two ends of the liquid drainage layer 50 are connected to the outermost filter layer. The liquid drainage layer 50 is made of non-woven fabric or woven fabric, with a thickness in the range of 0.1-3mm, and an average pore diameter of more than 70 μm. It plays the role of outer layer protection and liquid drainage, and can effectively avoid the problem through synergy with the micron fiber modified layer. To prevent secondary entrainment of droplets, two bonding methods, misplaced glue spraying or knitting, are used at the edge. It is best to use both bonding methods at the same time to ensure the bonding strength of the outermost layer. Under certain conditions, a metal frame such as stainless steel can be added on the outermost side. The offset glue spraying method is the same as the above-mentioned offset glue spraying method. The knitting method is to sew the liquid drainage layer 50 along the edge.

Comparative experiments were conducted between the composite modified gas-liquid coalescing filter in the embodiment of the present invention and the traditional gas-liquid coalescing filter. The filtration performance in the embodiment of the present invention is significantly improved compared to the traditional gas-liquid coalescing filter.

The specific experimental parameters are as follows: the average pore size ratio of each nanofiber modified layer of the composite modified gas-liquid coalescing filter is 0.5, the average pore size ratio of each micron fiber modified layer is 0.6, and the average pore size ratio of each micron fiber modified layer and the corresponding nanofiber The average pore size ratio of the modified layer (such as the first micron fiber modified layer and the first nanofiber modified layer) is 13. The apparent airflow speed at the filter inlet is 0.1m/s, and the oil (dioctyl sebacate, DEHS) specified in the international test standard EN779 is used to generate aerosol. The droplet size range in the inlet aerosol is 0.04-20μm. , the concentration is 500-550mg/m ³ .

In Figure 4, the abscissa is the liquid accumulation amount per unit area, and the ordinate is the process pressure drop. Curve 1 in Figure 4 represents the embodiment of the present invention, and curve 2 represents the prior art. In Figure 5, the abscissa is particle size, and the ordinate is filtration efficiency. Curve 1 in Figure 5 represents the embodiment of the present invention, and curve 2 represents the prior art. The experimental results are as follows: as the accumulated amount of liquid per unit area increases, the pressure drop of the filter of the present invention increases slowly. More liquid is discharged from the bottom of the filter during the filtration process, and the captured liquid will not block the air flow channel. It is beneficial to improve the operating life; at the same time, the steady-state pressure drop of the filter of the present invention is relatively low, which is reduced by about 600 Pa. The steady-state filtration efficiency of the filter of the present invention is significantly better than that of the traditional filter. The maximum value of the penetration rate (1 minus the efficiency value, that is, penetration rate + efficiency value = 1, where the efficiency value is common knowledge in the field) is reduced from 4.85% to 4.85%. It has reached 1.76%, and the filtration efficiency of droplets in the most penetrating particle size range has been significantly improved. At the same time, it can effectively reduce the secondary entrainment of droplets for droplets above 4 μm.

From the above description, it can be seen that the above-mentioned embodiments of the present invention achieve the following technical effects:

In terms of appearance design, compared with traditional gas-liquid coalescing filters or modular combined filtration and coalescing filtration equipment, the present invention has a compact structure and is easy to install and use.

In terms of structure, by adopting a new structural design in which nanofiber modified layers and micron fiber modified layers are alternately compounded, compared to the direct compounding of multiple layers of nanofibers, the present invention overcomes the internal accumulation caused by the thicker nanofiber modified layer. The problem of insufficient liquid and drain channels is eliminated, thereby ensuring high-efficiency filtration with a low pressure drop. On this basis, each nanofiber modified layer is set up with a pore size increasing structure to optimize the relative value of the average pore size, which is conducive to the coalescence and growth of droplets inside the filter material to form a matching relationship with the pore size of the nanofiber modified layer, reducing the filtration pressure. Reduce operating costs; moreover, setting up a pore size increasing structure for each micron fiber modified layer is conducive to forming a matching relationship between the drainage droplets inside the filter material and the pore size of the micron fiber modified layer, promoting the smooth discharge of the droplets, and further reducing the Filtration pressure drop and operating costs.

Through the synergistic effect of the internal micron fiber modified layers and the outermost liquid drainage layer, it can ensure that the filter can drain liquid smoothly under different working conditions of inlet gas liquid content, and reduce the possibility of secondary entrainment of droplets. occur.

In terms of processing, by setting a 4/3 turn winding method for the nanofiber modified layer, it helps to avoid leakage points and ensure the integrity of the filtration effect in all parts of the filter. By using misaligned glue spraying at the edge junctions of different layers, the strength can be ensured without affecting the effective filtration area, and the increase in filtration resistance caused by the glue is not obvious. At the same time, misplaced glue spraying can form a curved channel, which is conducive to interception. and inertial action to capture droplets and improve filtration efficiency.

In terms of material modification treatment, through low-pressure plasma surface modification technology, the nanofiber modified layer and micron fiber modified layer are treated with hydrophobic and oleophobic and super hydrophilic and super oleophilic respectively, which is environmentally friendly and eliminates waste of processing solvents. It can also ensure that the surface treatment of each fiber inside the filter material is uniform, and the effect is permanent, reducing the cost of solution treatment by more than 50%.

Compared with traditional gas-liquid coalescing filters, embodiments of the present invention can effectively reduce production and operation costs by more than 30%. Under the same working conditions, compared with the average service life of traditional filters of 3 months, the present invention can effectively extend the service life by more than 2 months.

The above are only specific embodiments of the present invention and cannot be used to limit the scope of the invention. Therefore, the replacement of equivalent components, or equivalent changes and modifications made according to the patent protection scope of the present invention, should still be covered by this patent. category. In addition, the technical features in the present invention can be freely combined with each other, between technical features and technical solutions, and between technical solutions and technical solutions.

Claims (10)

1. A composite modified gas-liquid coalescing filter, characterized in that the composite modified gas-liquid coalescing filter includes: Tubular skeleton (10); The first filter layer (20) includes a first nanofiber modified layer (21) and a first micron fiber modified layer (22), a first nanofiber modified layer (21) and a first micron fiber modified layer (21). 22) Wrap the cylindrical frame (10) at least once, the head end of the first nanofiber modified layer (21) is set on the outer wall surface of the cylindrical frame (10), and the first micron fiber modified layer (22) The first end edge is seamlessly connected to the end edge of the first nanofiber modified layer (21), and the first micron fiber modified layer (22) is wound around the outside of the first nanofiber modified layer (21); The second filter layer (30) includes a second nanofiber modified layer (31) and a second micron fiber modified layer (32), a second nanofiber modified layer (31) and a second micron fiber modified layer (31). 32) Wrap the cylindrical frame (10) for at least one week, the first edge of the second nanofiber modified layer (31) is seamlessly connected with the end edge of the first micron fiber modified layer (22), and the second nanofiber modified layer (31) is seamlessly connected to the end edge of the first micron fiber modified layer (22). The fiber modified layer (31) is wound around the outside of the first micron fiber modified layer (22), and the first edge of the second micron fiber modified layer (32) and the end edge of the second nanofiber modified layer (31) Seamlessly connected, and the second micron fiber modified layer (32) is wound around the outside of the second nanofiber modified layer (31); The pore diameters of the first nanofiber modified layer and the second nanofiber modified layer gradually increase; the pore diameters of the first micron fiber modified layer and the second micron fiber modified layer gradually increase; The first nanofiber modified layer (21) and the second nanofiber modified layer (31) have hydrophobic and oleophobic properties, and the first micron fiber modified layer (22) and the second micron fiber modified layer (32) have super Hydrophilic and super lipophilic properties; The ratio of the pore diameter of the first nanofiber modified layer (21) to the pore diameter of the second nanofiber modified layer (31) is 0.3 to 0.9, and the ratio of the pore diameter of the first micron fiber modified layer (22) to the pore diameter of the second micron fiber modified layer The aperture ratio of layer (32) ranges from 0.4 to 0.9. 2. The composite modified gas-liquid coalescing filter according to claim 1, characterized in that the composite modified gas-liquid coalescing filter further includes a third filter layer (40), the third filter layer (40) includes a third nanofiber modified layer (41) and a third micron fiber modified layer (42). The first edge of the third nanofiber modified layer (41) is in contact with the second micron fiber modified layer (32). ) are seamlessly connected, and the third nanofiber modified layer (41) is wound around the outside of the second micron fiber modified layer (32), and the first edge of the third micron fiber modified layer (42) is connected to the first end edge of the second micron fiber modified layer (42). The end edges of the three nanofiber modified layers (41) are seamlessly connected, and the third micron fiber modified layer (42) is wound around the outside of the third nanofiber modified layer (41). 3. The composite modified gas-liquid coalescing filter according to claim 2, characterized in that, along the radial direction of the cylindrical frame (10) from the inside to the outside, The pore sizes of the first nanofiber modified layer (21), the second nanofiber modified layer (31) and the third nanofiber modified layer (41) gradually increase; The pore sizes of the first micron fiber modified layer (22), the second micron fiber modified layer (32) and the third micron fiber modified layer (42) gradually increase. 4. The composite modified gas-liquid coalescing filter according to claim 2, characterized in that the pore diameter ratio of the second nanofiber modified layer (31) and the pore diameter of the third nanofiber modified layer (41) is 0.3 to 0.9, and the ratio of the pore diameter of the second micron fiber modified layer (32) to the pore diameter of the third micron fiber modified layer (42) is 0.4 to 0.9. 5. The composite modified gas-liquid coalescing filter according to claim 1, characterized in that, The thicknesses of the first nanofiber modified layer (21), the second nanofiber modified layer (31) and the third nanofiber modified layer (41) are all from 5 microns to 25 microns; The thicknesses of the first micron fiber modified layer (22), the second micron fiber modified layer (32) and the third micron fiber modified layer (42) are all from 0.1mm to 3mm. 6. The composite modified gas-liquid coalescing filter according to claim 1, characterized in that the inside of the first end of the first micron fiber modified layer (22) is connected by the first glue layer and the first nanofiber modified layer. (21) is bonded to the outside, the inner end of the first micron fiber modified layer (22) is bonded to the outer end of the first nanofiber modified layer (21) through the second glue layer, and the second nanofiber modified layer The inner side of the first end of (31) is bonded to the outer side of the first micron fiber modified layer (22) through the third glue layer. 7. The composite modified gas-liquid coalescing filter according to claim 6, characterized in that the first glue layer, the second glue layer and the third glue layer are each composed of a plurality of glue spraying points. The structure is such that the plurality of glue spraying points of the first glue layer and the plurality of glue spraying points of the third glue layer are disposed offset along the axial direction of the cylindrical frame (10). 8. The composite modified gas-liquid coalescing filter according to claim 1, characterized in that the composite modified gas-liquid coalescing filter further includes a liquid drainage layer (50), and the liquid drainage layer (50) The first end edge is seamlessly connected to the end edge of the second micron fiber modified layer (32), and the inner end of the liquid drainage layer (50) is attached to the outer side of the second micron fiber modified layer (32). 9. The composite modified gas-liquid coalescing filter according to claim 1, characterized in that the pore size of the liquid drainage layer (50) is greater than or equal to 70 μm, and the thickness of the liquid drainage layer (50) is 0.1 mm to 3 mm. 10. The composite modified gas-liquid coalescing filter according to claim 1, characterized in that the height direction of the first filter layer (20) and the height direction of the second filter layer (30) are along the cylindrical skeleton ( 10), the height of the first filter layer (20) and the height of the second filter layer (30) are the same as the axial height of the cylindrical frame (10).