A density gradient PPS fiber filter material, preparation process and filter bag

Abstract

The present invention belongs to the technical field of PPS filter felt, in particular to a PPS fiber filter material with a gradient density, a preparation process and a filter bag, comprising a filter material layer, wherein the filter material layer is made of a first surface layer, a base fabric layer and a second surface layer by needle punching; the thickness ratio of the first surface layer, the base fabric layer and the second surface layer is (3-10): (1-2): (5-10), and the first surface layer is a micro-denier PPS fiber layer, a fine-denier PPS fiber layer and a medium-denier PPS fiber layer from the outside to the inside. The PPS fiber filter material with a gradient density, a preparation process and a filter bag further increase the high temperature resistance of the filter bag body by setting the first suture line and the second suture line in the filter bag body to be one or more of a PPS fiber line, a PTFE fiber line and a 316L metal fiber line, and the metal fiber has unique properties and a wide range of uses like organic and inorganic fibers. The metal fiber has good electrical conductivity, thermal conductivity, magnetic conductivity and high temperature resistance, and the manufacturing method is relatively simple and the cost is low.

Description

Technical Field

[0001] The invention relates to the technical field of PPS filter felt, and in particular to a density gradient PPS fiber filter material, a preparation process and a filter bag. Background Art

[0002] The main goal of industrial dust removal technology is to control the emission of flue gas particulate matter from pollution sources and reduce air pollution. At present, the three main methods used to treat industrial high-temperature flue gas are wet dust removal, electrostatic precipitator, and bag dust removal. Among them, bag dust collectors are superior to wet dust removal and electrostatic precipitator in terms of dust removal efficiency, one-time and long-term investment costs, equipment requirements and performance. They will gradually replace the latter two and occupy the mainstream industrial dust collector market. The core of bag dust collectors is high-temperature resistant filter materials. The performance of high-temperature resistant filter materials will directly affect the high efficiency, stability, reliability and long-term operation of dust collectors.

[0003] Bag dust collector is the main equipment for controlling fine particles, and filter material is the core consumable of bag dust collector. The filter cloth used in existing filter bags is mainly made of PPS fibers vertically interwoven with each other. Due to the performance limitations of PPS fibers themselves, existing PPS filter bags still have the problem of low high temperature resistance. Therefore, a density gradient PPS fiber filter material, preparation process and filter bag are needed. Summary of the invention

[0004] Based on the technical problem that the existing filter bags have low high temperature resistance, the present invention proposes a density gradient PPS fiber filter material, a preparation process and a filter bag.

[0005] The present invention provides a PPS fiber filter material with a gradient density, comprising a filter material layer, wherein the filter material layer is made of a first surface layer, a base fabric layer, and a second surface layer by needle punching;

[0006] The thickness ratio of the first surface layer, the base fabric layer and the second surface layer is (3-10): (1-2): (5-10), and the first surface layer is composed of a micro-denier PPS fiber layer, a fine-denier PPS fiber layer and a medium-denier PPS fiber layer from the outside to the inside;

[0007] The fiber fineness of the micro-denier PPS fiber layer is (0.6-1.0D);

[0008] The fiber fineness of the fine denier PPS fiber layer is (0.8-1.2D);

[0009] The fiber fineness of the medium denier PPS fiber layer is (1.0-1.5D);

[0010] The mass ratio of the micro-denier PPS layer, the fine-denier PPS fiber layer, and the medium-denier PPS fiber layer is (1-2): (2-4): (1-3);

[0011] The second surface layer comprises coarse-denier PPS fibers (1.5-2.0D).

[0012] Preferably, the micro-denier PPS fiber layer comprises micro-denier PPS fiber, PTFE fiber, and stainless steel metal fiber; the mass ratio of the micro-denier PPS fiber, PTFE fiber, and stainless steel metal fiber is (75-90): (1-8): (1-2);

[0013] The fine-denier PPS fiber layer comprises fine-denier PPS fibers and stainless steel metal fibers; the mass ratio of the fine-denier PPS fibers to the stainless steel metal fibers is (80-90): (2-5);

[0014] The medium-denier PPS fiber layer comprises fine-denier PPS fibers and stainless steel metal fibers; the mass ratio of the medium-denier PPS fibers to the stainless steel metal fibers is (70-90):(5-10).

[0015] Preferably, the device further comprises an impregnation layer, the thickness of the impregnation layer is 120-550 microns; the impregnation layer is formed by curing an impregnation liquid, and the impregnation liquid comprises polytetrafluoroethylene emulsion, ethanol, and methyl silicone oil.

[0016] Preferably, the coating layer further comprises a coating layer, the coating layer is located outside the impregnation layer close to the first surface layer, the coating layer has a thickness of 30-60 microns, and the coating layer is composed of a PTFE film.

[0017] Preferably, the base fabric layer is composed of warp yarn and weft yarn; the warp yarn is formed by plying and twisting fine-denier PPS fibers; the weft yarn is formed by plying and twisting fine-denier PPS fibers and fine-denier stainless steel fibers; the weight ratio of fine-denier PPS fibers to fine-denier stainless steel fibers in the weft yarn is (7-15):1.

[0018] Preferably, the base fabric layer is composed of warp yarns and weft yarns; the warp yarns are formed by plying and twisting fine-denier PPS fibers; the weft yarns include PPS weft yarns formed by plying and twisting fine-denier PPS fibers and metal weft yarns formed by twisting fine-denier stainless steel metal fibers; the ratio of the number of PPS weft yarns to fine metal weft yarns in the weft yarns is (5-15):1.

[0019] Preferably, a process for preparing a density gradient PPS fiber filter material comprises the following steps:

[0020] S1: preparing the base fabric layer, plying fine-denier PPS fibers and fine-denier stainless steel metal fibers to form warp and weft threads and weaving them into a base fabric;

[0021] S2: The mass ratio of the micro-denier PPS layer, the fine-denier PPS fiber layer, and the medium-denier PPS fiber layer from outside to inside is (1-2): (2-4): (1-3) air-laid to prepare the first surface layer; the coarse-denier PPS fiber of (1.5-2.0D) is air-laid to prepare the second surface layer;

[0022] S3: placing a prefabricated first surface layer and a prefabricated second surface layer on the upper surface and the lower surface of the base fabric layer respectively, and forming a filter fabric by needle punching;

[0023] S4: After calendering and singeing the filter fabric, put it into the impregnation liquid for impregnation;

[0024] S5: The impregnated filter fabric is subjected to high temperature shaping treatment to prepare a filter material.

[0025] Preferably, the impregnation liquid in S4 comprises polytetrafluoroethylene emulsion, ethanol and methyl silicone oil, the ratio of polytetrafluoroethylene emulsion, ethanol and methyl silicone oil is (12-16): (10-20): (20-40), and the residence time of the impregnation liquid is 0.5-2s.

[0026] The shaping treatment in S5 is carried out in three temperature ranges of 100-150°C, 150-200°C and 160-180°C from the inlet to the outlet, and the ratio of 100-150°C, 150-200°C and 160-180°C to the shaping time is 1:(2-3):(0.5-1).

[0027] Preferably, in S3, the needling process comprises a needling density of 100-300 needles / , wherein the pre-needling stage is 100-150 needles / , and the main needling stage is 150-300 needles / .

[0028] Preferably, a filter bag made of a PPS fiber filter material with a gradient density comprises a filter bag body, wherein the filter bag body comprises a cylinder and a bag bottom, wherein the cylinder body is formed by sewing the filter material through a first suture line, wherein the first suture line is one or more of a PPS fiber line, a PTFE fiber line, and a 316L metal fiber line;

[0029] The bag bottom and the cylinder are sewn together by a second suture line, and the second suture line is one or more of a PPS fiber line, a PTFE fiber line, and a 316L metal fiber line;

[0030] The outer surfaces of the first suture thread and the second suture thread are also provided with a protective layer, and the protective layer is any one of silica gel and hot melt adhesive.

[0031] The beneficial effects of the present invention are:

[0032] 1. By setting up a gradient PPS filter material, the risk that the existing PPS filter bag cannot withstand static electricity is solved;

[0033] 2. By arranging the first surface layer, the base fabric layer, the second surface layer, and the first surface layer from the outside to the inside, the micro-denier PPS fiber layer, the fine-denier PPS fiber layer, and the medium-denier PPS fiber layer, the density of the filter material layer is gradually improved, the three-dimensional filtering effect is increased, and dust particles of different sizes can be filtered to avoid clogging problems.

[0034] 3. By setting the first suture and the second suture in the filter bag body to be one or more of PPS fiber line, PTFE fiber line, and 316L metal fiber line, the high temperature resistance of the filter bag body is further increased. Metal fiber has unique properties and a wide range of uses like organic and inorganic fibers. Metal fiber has good electrical conductivity, thermal conductivity, magnetic conductivity and high temperature resistance, and the manufacturing method is relatively simple and the cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a side cross-sectional view of the filter material layer structure of the present invention;

[0036] Figure 2 It is a front view of the filter felt structure of the present invention;

[0037] Figure 3 It is a front view of the PPS fiber and ceramic fiber structure of the present invention;

[0038] Figure 4 It is a three-dimensional diagram of the structure of the filter bag body of the present invention;

[0039] Figure 5 A three-dimensional diagram of the fixing ring structure of the filter bag of the present invention;

[0040] Figure 6 A cross-sectional view of a locking ring structure of the present invention;

[0041] Figure 7 For the present invention Figure 5 A magnified view of the structure at C in the middle;

[0042] Figure 8 It is a three-dimensional diagram of the cylinder structure of the present invention.

[0043] In the figure: 1. filter felt cloth; 2. filter bag cylinder; 3. filter bag body; 301. fixing ring; 302. connecting ring; 303. connecting pipe; 304. locking ring; 305. slide groove; 306. sliding ring; 307. limiting pipe; 308. sealing airbag; 309. inflation tube; 310. supporting ring; 311. sealing ring; 312. spring; 313. sealing ball; 314. sealing cover; 4. first surface layer; 5. base fabric layer; 6. second surface layer; 7. impregnation layer; 8. coating layer; 9. cylinder; 10. bag bottom; 11. PPS fiber; 12. ceramic fiber. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0045] Embodiment 1

[0046] Reference Figure 1 , a density gradient PPS fiber filter material: comprising a filter material layer, an impregnation layer, and a coating layer, wherein the filter material layer is made of a first surface layer 4, a base fabric layer 5, and a second surface layer 6 by needle punching; the thickness ratio of the first surface layer 4, the base fabric layer 5, and the second surface layer 6 is 3:1:5, and the first surface layer 4 is composed of a micro-denier PPS fiber layer, a fine-denier PPS fiber layer, and a medium-denier PPS fiber layer from the outside to the inside;

[0047] By arranging the first surface layer 4, the base fabric layer 5, the second surface layer 6, and the first surface layer (4) to be a micro-denier PPS fiber layer, a fine-denier PPS fiber layer, and a medium-denier PPS fiber layer from the outside to the inside, the density of the filter material layer is gradually improved, the three-dimensional filtering effect is increased, and dust particles of different sizes can be filtered to avoid clogging problems;

[0048] The fiber fineness of the micro-denier PPS fiber layer is (0.6-1.0D);

[0049] The fiber fineness of the fine denier PPS fiber layer is (0.8-1.2D);

[0050] The fiber fineness of the medium-denier PPS fiber layer is (1.0-1.5D);

[0051] The mass ratio of micro-denier PPS layer, fine-denier PPS fiber layer, and medium-denier PPS fiber layer is 1:2:1;

[0052] The second surface layer comprises coarse denier PPS fibers (1.5-2.0D).

[0053] The micro-denier PPS fiber layer comprises micro-denier PPS fibers, PTFE fibers, and stainless steel metal fibers; the mass ratio of the micro-denier PPS fibers, PTFE fibers, and stainless steel metal fibers is 75:1:1;

[0054] The fine-denier PPS fiber layer comprises fine-denier PPS fibers and stainless steel metal fibers; the mass ratio of the fine-denier PPS fibers to the stainless steel metal fibers is 80:2;

[0055] The medium-denier PPS fiber layer comprises medium-denier PPS fibers and stainless steel metal fibers; the mass ratio of the medium-denier PPS fibers to the stainless steel metal fibers is 70:5.

[0056] By arranging the first surface layer 4 to be a micro-denier PPS fiber layer, a fine-denier PPS fiber layer, and a medium-denier PPS fiber layer from the outside to the inside, the proportion of stainless steel metal fiber gradually increases from the outside to the inside fiber layer, which is convenient for eliminating static electricity in static electricity occasions.

[0057] The thickness of the impregnation layer 7 is 120 microns; the impregnation layer 7 is formed by curing an impregnation liquid, wherein the impregnation liquid comprises polytetrafluoroethylene emulsion, ethanol, methyl silicone oil, and of course, the impregnation liquid also comprises deionized water, and the deionized water accounts for 80% of the total mass ratio of the impregnation liquid.

[0058] The coating layer 8 is located outside the impregnation layer close to the first surface layer 4 , the coating layer 8 has a thickness of 30 microns, and the coating layer 8 is composed of a PTFE film.

[0059] The base fabric layer 5 is composed of warp yarn and weft yarn; the warp yarn is formed by plying and twisting fine-denier PPS fibers; the weft yarn is formed by plying and twisting fine-denier PPS fibers and fine-denier stainless steel fibers; the weight ratio of the fine-denier PPS fibers to the fine-denier stainless steel fibers in the weft yarn is 7:1;

[0060] Or the base fabric layer 5 is composed of warp yarn and weft yarn; the warp yarn is formed by plying and twisting fine-denier PPS fibers; the weft yarn includes PPS weft yarn formed by plying and twisting fine-denier PPS fibers and metal weft yarn formed by twisting fine-denier stainless steel metal fibers; the ratio of the number of PPS weft yarn to the fine metal weft yarn in the weft yarn is 5:1.

[0061] Embodiment 2

[0062] Reference Figure 1 A density gradient PPS fiber filter material: comprising a filter material layer, an impregnation layer 7, and a coating layer 8, wherein the filter material layer is made of a first surface layer 4, a base fabric layer, and a second surface layer 6 by needle punching; the thickness ratio of the first surface layer 4, the base fabric layer 5, and the second surface layer 6 is 10:2:10, and the first surface layer is composed of a micro-denier PPS fiber layer, a fine-denier PPS fiber layer, and a medium-denier PPS fiber layer from the outside to the inside;

[0063] By arranging the first surface layer 4, the base fabric layer 5, the second surface layer 6, and the first surface layer (4) to be a micro-denier PPS fiber layer, a fine-denier PPS fiber layer, and a medium-denier PPS fiber layer from the outside to the inside, the density of the filter material layer is gradually improved, the three-dimensional filtering effect is increased, and dust particles of different sizes can be filtered to avoid clogging problems;

[0064] The fiber fineness of the micro-denier PPS fiber layer is (0.6-1.0D);

[0065] The fiber fineness of the fine denier PPS fiber layer is (0.8-1.2D);

[0066] The fiber fineness of the medium-denier PPS fiber layer is (1.0-1.5D);

[0067] The mass ratio of micro-denier PPS layer, fine-denier PPS fiber layer, and medium-denier PPS fiber layer is 2:4:3;

[0068] The second surface layer comprises coarse denier PPS fibers (1.5-2.0D).

[0069] The micro-denier PPS fiber layer comprises micro-denier PPS fibers, PTFE fibers, and stainless steel metal fibers; the mass ratio of the micro-denier PPS fibers, PTFE fibers, and stainless steel metal fibers is 90:8:2;

[0070] The fine-denier PPS fiber layer comprises fine-denier PPS fibers and stainless steel metal fibers; the mass ratio of the fine-denier PPS fibers to the stainless steel metal fibers is 90:5;

[0071] The medium-denier PPS fiber layer comprises medium-denier PPS fibers and stainless steel metal fibers; the mass ratio of the medium-denier PPS fibers to the stainless steel metal fibers is 90:10.

[0072] By arranging the first surface layer 4 to be a micro-denier PPS fiber layer, a fine-denier PPS fiber layer, and a medium-denier PPS fiber layer from the outside to the inside, the fiber layers increase gradually from the outside to the inside, which facilitates the elimination of static electricity in static electricity situations.

[0073] The thickness of the impregnation layer 7 is 550 microns; the impregnation layer 7 is formed by curing an impregnation liquid, wherein the impregnation liquid comprises polytetrafluoroethylene emulsion, ethanol, methyl silicone oil, and of course, the impregnation liquid also comprises deionized water, and the deionized water accounts for 85% of the total mass ratio of the impregnation liquid.

[0074] Of course, compared with the first embodiment, the thickness of this embodiment has been increased, so the coating layer 8 is not required to meet the filtering accuracy requirements.

[0075] The base fabric layer 5 is composed of warp yarn and weft yarn; the warp yarn is formed by plying and twisting fine-denier PPS fibers; the weft yarn is formed by plying and twisting fine-denier PPS fibers and fine-denier stainless steel fibers; the weight ratio of the fine-denier PPS fibers to the fine-denier stainless steel fibers in the weft yarn is 15:1;

[0076] Or the base fabric layer 5 is composed of warp yarn and weft yarn; the warp yarn is formed by plying and twisting fine-denier PPS fibers; the weft yarn includes PPS weft yarn formed by plying and twisting fine-denier PPS fibers and metal weft yarn formed by twisting fine-denier stainless steel metal fibers; the ratio of the number of PPS weft yarns to fine metal weft yarns in the weft yarn is 15:1.

[0077] Embodiment 3

[0078] Reference Figure 1 , a density gradient PPS fiber filter material: comprising a filter material layer, an impregnation layer, and a coating layer, wherein the filter material layer is made of a first surface layer 4, a base fabric layer 5, and a second surface layer 6 by needle punching; the thickness ratio of the first surface layer 4, the base fabric layer 5, and the second surface layer 6 is 7:1.5:8, and the first surface layer 4 is composed of a micro-denier PPS fiber layer, a fine-denier PPS fiber layer, and a medium-denier PPS fiber layer from the outside to the inside;

[0079] By arranging the first surface layer 4, the base fabric layer 5, the second surface layer 6, and the first surface layer (4) to be a micro-denier PPS fiber layer, a fine-denier PPS fiber layer, and a medium-denier PPS fiber layer from the outside to the inside, the density of the filter material layer is gradually improved, the three-dimensional filtering effect is increased, and dust particles of different sizes can be filtered to avoid clogging problems;

[0080] The fiber fineness of the micro-denier PPS fiber layer is (0.6-1.0D);

[0081] The fiber fineness of the fine denier PPS fiber layer is (0.8-1.2D);

[0082] The fiber fineness of the medium-denier PPS fiber layer is (1.0-1.5D);

[0083] The mass ratio of micro-denier PPS layer, fine-denier PPS fiber layer, and medium-denier PPS fiber layer is 1.5:3:2;

[0084] The second surface layer comprises coarse denier PPS fibers (1.5-2.0D).

[0085] The micro-denier PPS fiber layer comprises micro-denier PPS fibers, PTFE fibers, and stainless steel metal fibers; the mass ratio of the micro-denier PPS fibers, PTFE fibers, and stainless steel metal fibers is 83:5:1.5;

[0086] The fine-denier PPS fiber layer comprises fine-denier PPS fibers and stainless steel metal fibers; the mass ratio of the fine-denier PPS fibers to the stainless steel metal fibers is 85:3;

[0087] The medium-denier PPS fiber layer comprises medium-denier PPS fibers and stainless steel metal fibers; the mass ratio of the medium-denier PPS fibers to the stainless steel metal fibers is 80:7.

[0088] By arranging the first surface layer 4 to be a micro-denier PPS fiber layer, a fine-denier PPS fiber layer, and a medium-denier PPS fiber layer from the outside to the inside, the fiber layers increase gradually from the outside to the inside, which facilitates the elimination of static electricity in static electricity situations.

[0089] The thickness of the impregnation layer 7 is 250 microns; the impregnation layer 7 is formed by curing the impregnation liquid, the impregnation liquid includes polytetrafluoroethylene emulsion, ethanol, methyl silicone oil, and of course the impregnation liquid also includes deionized water, and the deionized water accounts for 75% of the total mass of the impregnation liquid.

[0090] The coating layer 8 is located outside the impregnation layer close to the first surface layer. The coating layer 8 has a thickness of 45 microns and is composed of a PTFE film.

[0091] The base fabric layer 5 is composed of warp yarn and weft yarn; the warp yarn is formed by plying and twisting fine-denier PPS fibers; the weft yarn is formed by plying and twisting fine-denier PPS fibers and fine-denier stainless steel fibers; the weight ratio of the fine-denier PPS fibers to the fine-denier stainless steel fibers in the weft yarn is 7:1;

[0092] Or the base fabric layer 5 is composed of warp yarn and weft yarn; the warp yarn is formed by plying and twisting fine-denier PPS fibers; the weft yarn includes PPS weft yarn formed by plying and twisting fine-denier PPS fibers and metal weft yarn formed by twisting fine-denier stainless steel metal fibers; the ratio of the number of PPS weft yarn to the fine metal weft yarn in the weft yarn is 10:1.

[0093] Embodiment 4

[0094] Reference Figure 1 , a preparation process of a density gradient PPS fiber filter material, comprising the following steps;

[0095] S1: preparing the base fabric layer 5, plying fine-denier PPS fibers and fine-denier stainless steel metal fibers to form warp and weft threads and weaving them into a base fabric;

[0096] S2: Preform the first surface layer by air-laying a micro-denier PPS layer, a fine-denier PPS fiber layer, and a medium-denier PPS fiber layer in a mass ratio of 1:2:1 from outside to inside; preform the second surface layer by air-laying a coarse-denier PPS fiber (1.5-2.0D);

[0097] S3: placing a prefabricated first surface layer and a prefabricated second surface layer on the upper surface and the lower surface of the base fabric layer respectively, and forming a filter fabric by needle punching;

[0098] S4: After calendering and singeing the filter fabric, put it into the impregnation liquid for impregnation;

[0099] S5: The impregnated filter fabric is subjected to high temperature shaping treatment to prepare a filter material.

[0100] In S3, the pre-needling stage in the needling process is 100 needles / , and the main needling stage is 150 needles / ;

[0101] In S4, the impregnation liquid includes polytetrafluoroethylene emulsion, ethanol, and methyl silicone oil, and the ratio of polytetrafluoroethylene emulsion, ethanol, and methyl silicone oil is 12:10:20. Of course, the impregnation liquid also includes deionized water, and the deionized water accounts for 75% of the total mass of the impregnation liquid. The residence time of the impregnation liquid is 0.5s.

[0102] The shaping treatment in S5 is carried out in three temperature ranges of 100-150°C, 150-200°C and 160-180°C from the inlet to the outlet, and the ratio of 100-150°C, 150-200°C and 160-180°C to the shaping time is 1:2:0.5.

[0103] Embodiment 5

[0104] Reference Figure 7 , a preparation process of a density gradient PPS fiber filter material, comprising the following steps;

[0105] S1: preparing the base fabric layer 5, plying fine-denier PPS fibers and fine-denier stainless steel metal fibers to form warp and weft threads and weaving them into a base fabric;

[0106] S2: Preform the first surface layer 4 by air-laying a micro-denier PPS layer, a fine-denier PPS fiber layer, and a medium-denier PPS fiber layer in a mass ratio of 2:4:3 from outside to inside; preform the second surface layer 6 by air-laying a coarse-denier PPS fiber (1.5-2.0D);

[0107] S3: placing a prefabricated first surface layer 4 and a prefabricated second surface layer 6 on the upper surface and the lower surface of the base fabric layer 5 respectively, and forming a filter fabric by needle punching;

[0108] S4: After calendering and singeing the filter fabric, put it into the impregnation liquid for impregnation;

[0109] S5: The impregnated filter fabric is subjected to high temperature shaping treatment to prepare a filter material.

[0110] In S3, the pre-needling stage in the needling process is 150 needles / , and the main needling stage is 300 needles / ;

[0111] In S4, the impregnation liquid includes polytetrafluoroethylene emulsion, ethanol, and methyl silicone oil, and the ratio of polytetrafluoroethylene emulsion, ethanol, and methyl silicone oil is 16:20:40. Of course, the impregnation liquid also includes deionized water, and the deionized water accounts for 85% of the total mass of the impregnation liquid. The residence time of the impregnation liquid is 2s.

[0112] In S5, the shaping treatment in S5 is carried out in three temperature ranges of 130-150°C, 150-190°C and 160-180°C from the inlet to the outlet, and the ratio of 130-150°C, 150-190°C and 160-180°C to the shaping time is 1:3:1.

[0113] Embodiment 6

[0114] Reference Figure 7 , a preparation process of a density gradient PPS fiber filter material, comprising the following steps;

[0115] S1: preparing the base fabric layer 5, plying fine-denier PPS fibers and fine-denier stainless steel metal fibers to form warp and weft threads and weaving them into a base fabric;

[0116] S2: Preform the first surface layer 4 by air-laying a micro-denier PPS layer, a fine-denier PPS fiber layer, and a medium-denier PPS fiber layer in a mass ratio of 1.5:3:2 from outside to inside; preform the second surface layer 6 by air-laying a coarse-denier PPS fiber (1.5-2.0D);

[0117] S3: placing a prefabricated first surface layer 4 and a prefabricated second surface layer 6 on the upper surface and the lower surface of the base fabric layer 5 respectively, and forming a filter fabric by needle punching;

[0118] S4: After calendering and singeing the filter fabric, put it into the impregnation liquid for impregnation;

[0119] S5: The impregnated filter fabric is subjected to high temperature shaping treatment to prepare a filter material.

[0120] In S3, the pre-needling stage in the needling process is 125 needles / , and the main needling stage is 230 needles / ;

[0121] In S4, the impregnation liquid includes polytetrafluoroethylene emulsion, ethanol, and methyl silicone oil, and the ratio of polytetrafluoroethylene emulsion, ethanol, and methyl silicone oil is 14:15:32. Of course, the impregnation liquid also includes deionized water, and the deionized water accounts for 78% of the total mass of the impregnation liquid. The residence time of the impregnation liquid is 0.8s.

[0122] In S5, the shaping treatment is carried out in three temperature intervals of 130-150°C, 150-200°C and 160-170°C from the inlet to the outlet, and the ratio of 130-150°C, 150-200°C and 160-170°C to the shaping time is 1:2.4:0.8.

[0123] Embodiment 7

[0124] Reference Figure 1 and Figure 8 , a filter bag made of a PPS fiber filter material with a gradient density, comprising a filter bag body;

[0125] The filter bag body includes a cylinder 9 and a bag bottom 10, and the cylinder body is formed by sewing the filter material through a first suture line, and the first suture line is one or more of a PPS fiber line, a PTFE fiber line, and a 316L metal fiber line;

[0126] The bag bottom 10 and the cylinder 9 are sewn together by a second suture line, and the second suture line is one or more of a PPS fiber line, a PTFE fiber line, and a 316L metal fiber line;

[0127] The outer surfaces of the first suture thread and the second suture thread are also provided with a protective layer, and the protective layer is any one of silica gel and hot melt adhesive.

[0128] Embodiment 8

[0129] Reference Figure 2-7 A filter bag made of a density gradient PPS fiber filter material, comprising a filter felt cloth 1, a filter bag tube 2 and a filter bag body 3, wherein the filter felt cloth 1 is made of PPS fiber 11, ceramic fiber 12, super absorbent fiber and chitin fiber;

[0130] The filter bag tube 2 is made by sewing the filter felt cloth 1;

[0131] The filter bag tube 2 is made by sewing the filter felt cloth 1 into a bottomed cylindrical shape by a sewing machine;

[0132] The filter bag body 3 is composed of the filter bag cylinder 2 and a connecting mechanism;

[0133] The preparation process of the filter felt cloth 1 specifically comprises the following steps:

[0134] Step 1: interweave two PPS fibers 11 and two ceramic fibers 12 in a cross-shaped pattern to form a base skeleton;

[0135] Step 2: Weaving the ceramic fiber 12, the super absorbent fiber and the PPS fiber 11 in sequence on the base skeleton in an interlaced manner to form a base fabric;

[0136] Step 3: After the PPS fiber 11 and the chitin fiber are evenly mixed, a mixed filter fiber layer is prepared by an air-laid machine;

[0137] Step 4: Laying and stacking mixed fiber layers on the upper and lower surfaces of the base fabric, and bonding the mixed fiber layers to the upper and lower surfaces of the base fabric through a needle punching machine to form a filter felt cloth 1;

[0138] Step 5: stretching treatment, stretching the filter felt cloth 1 prepared in step 4 through a stretching machine;

[0139] In step 5, the stretching treatment is to stretch the filter felt cloth 1 along the warp direction, and the width of the filter felt cloth 1 increases by 15%-20% after the stretching;

[0140] Step 6: Put the stretched filter felt cloth 1 into the mixed emulsion for impregnation;

[0141] In step 6, the mixed emulsion is 12%-16% of polytetrafluoroethylene emulsion, 1%-2% of coupling agent, 2%-4% of methyl silicone oil, and the balance is water, and the coupling agent is a silane coupling agent;

[0142] Step 7, drying and high-temperature shaping the impregnated filter felt cloth 1;

[0143] In step 7, the drying temperature is 100°C-160°C, the drying time is 0.5-1 hour, the high temperature setting temperature is 190°C-240°C, and the setting time is 8-20 minutes;

[0144] Two PPS fibers 11 and two ceramic fibers 12 are interwoven in a cross-shaped pattern to form a base frame, and then the ceramic fibers 12, super-absorbent fibers and PPS fibers 11 are interlaced and woven on the base frame in sequence to form a base cloth. When in use, the ceramic fibers 12 have the advantages of light weight, high temperature resistance, good thermal stability, low thermal conductivity, low specific heat and mechanical vibration resistance, and the super-absorbent fibers have better adsorption of particulate matter in the flue gas and water vapor generated during the cooling process of the high-temperature flue gas, thereby achieving better high temperature resistance and filtering effects, thereby solving the problem of low high temperature resistance of the existing filter bag.

[0145] The filter bag body 3 includes a fixing ring 301;

[0146] Furthermore, when in use, the fixing ring 301 is fixedly connected to the surface of the bag filter installation hole by means of a sealant, thereby achieving a better sealing connection effect;

[0147] The lower surface of the fixing ring 301 is fixedly connected with a connecting ring 302, and the surface of the connecting ring 302 is fixedly connected with a connecting pipe 303, the surface of the connecting pipe 303 is conical, and the connecting mechanism includes a locking ring 304, the inner wall of the locking ring 304 is threadedly connected with the surface of the connecting ring 302, the inner wall of the filter bag cartridge 2 is slidably connected with the surface of the connecting pipe 303, and the surface of the locking ring 304 is fixedly provided with a sliding groove 305, the inner wall of the sliding groove 305 is T-shaped, and the inner wall of the sliding groove 305 is slidably connected with a slip ring 306, the surface of the slip ring 306 extends to the lower surface of the locking ring 304, and the surface of the slip ring 306 is fixedly connected with a limiting tube 307, the inner wall of the surface of the limiting tube 307 is conical, the inner wall of the limiting tube 307 is provided with knurling, and the inner wall of the limiting tube 307 is plugged into the surface of the filter bag cartridge 2;

[0148] The inner wall of the limiting tube 307 is fixedly connected with a sealing airbag 308, the surface of the sealing airbag 308 is plugged with the surface of the filter bag tube 2, the inner wall of the sealing airbag 308 is fixedly connected with an inflation tube 309, one end of the inflation tube 309 passes through and extends to the surface of the limiting tube 307, the inner wall of the inflation tube 309 is respectively fixedly connected with a support ring 310 and a sealing ring 311, the surface of the support ring 310 is fixedly connected with a spring 312, one end of the spring 312 is fixedly connected with a spring 312, one end of the spring 312 is fixedly connected with a sealing ball 313, the surface of the sealing ball 313 is plugged with the inner wall of the sealing ring 311, the inner wall of one end of the inflation tube 309 is threadedly connected with a sealing cap 314, the surface of the sealing cap 314 is slidably connected with the surface of the inflation tube 309;

[0149] The filter bag body 3 is composed of a filter bag barrel 2 and a connecting mechanism. When in use, the filter bag body 3 is installed separately from the filter bag barrel 2 by using the installation connecting mechanism. When installing, the surface of the fixing ring 301 is plugged into the surface of the bag filter installation hole, and then the inner wall of the filter bag barrel 2 is plugged into the surface of the connecting pipe 303. Then, after the inner wall of the limiting pipe 307 is plugged into the surface of the filter bag barrel 2, the locking ring 304 is threadedly connected to the surface of the connecting ring 302 to fix the filter bag barrel 2 and connect the connecting pipe 303. Finally, the sealing cover 314 is opened and the sealing ball 313 is pressed to separate the surface of the sealing ball 313 from the inner wall of the sealing ring 311. 09 Inflate the sealing airbag 308, and the sealing airbag 308 expands after being inflated. The surface of the sealing airbag 308 is plugged and tightened with the surface of the filter bag tube 2 and the inner wall of the limiting tube 307, so as to further seal the limiting tube 307 and the filter bag tube 2. After the inflation is completed, release the sealing ball 313. Under the action of the spring 312, the sealing ball 313 automatically plugs and seals with the inner wall of the sealing ring 311, and then the sealing cover 314 is threadedly connected and sealed with the inflation tube 309, so as to achieve the effect of facilitating installation and better installing and sealing the filter bag and the dust collector, thereby solving the problem of low reuse rate of the existing filter bag installation frame, causing waste of resources and inconvenient installation.

[0150] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A PPS fiber filter material with a gradient density, comprising a filter material layer, wherein the filter material layer is made of a first surface layer (4), a base fabric layer (5), and a second surface layer (6) by needle punching; characterized in that: The thickness ratio of the first surface layer (4), the base fabric layer (5), and the second surface layer (6) is (3-10): (1-2): (5-10). The first surface layer (4) comprises a micro-denier PPS fiber layer, a fine-denier PPS fiber layer, and a medium-denier PPS fiber layer from the outside to the inside. The fiber fineness of the micro-denier PPS fiber layer is (0.6-1.0D); the fiber fineness of the fine-denier PPS fiber layer is (0.8-1.2D); the fiber fineness of the medium-denier PPS fiber layer is (1.0-1.5D). The mass ratio of the micro-denier PPS layer, the fine-denier PPS fiber layer, and the medium-denier PPS fiber layer is (1-2): (2-4): (1-3). The second surface layer comprises coarse-denier PPS fibers of (1.5-2.0D). The micro-denier PPS fiber layer comprises micro-denier PPS fibers, PTFE fibers, and stainless steel. The base fabric layer (5) is composed of warp yarn and weft yarn; the warp yarn is formed by combining and twisting fine denier PPS fibers; the weft yarn is formed by combining fine denier PPS fibers and fine denier stainless steel fibers; the weight ratio of fine denier PPS fibers to fine denier stainless steel fibers is (75-90): (1-8): (1-2); the fine denier PPS fiber layer comprises fine denier PPS fibers and stainless steel fibers; the weight ratio of fine denier PPS fibers to stainless steel fibers is (80-90): (2-5); the medium denier PPS fiber layer comprises medium denier PPS fibers and stainless steel fibers; the weight ratio of medium denier PPS fibers to stainless steel fibers is (70-90): (5-10); the base fabric layer (5) is composed of warp yarn and weft yarn; the warp yarn is formed by combining and twisting fine denier PPS fibers; the weft yarn is formed by combining and twisting fine denier PPS fibers and fine denier stainless steel fibers; the weight ratio of fine denier PPS fibers to fine denier stainless steel fibers in the weft yarn is (7-15):

1.

2. The PPS fiber filter material with a gradient density according to claim 1, characterized in that: It also comprises an impregnation layer (7), the thickness of the impregnation layer (7) is 120-550 micrometers; the impregnation layer (7) is formed by curing an impregnation liquid, the impregnation liquid comprising polytetrafluoroethylene emulsion, ethanol and methyl silicone oil.

3. The PPS fiber filter material with a gradient density according to claim 1, characterized in that: It also comprises a coating layer (8), the coating layer (8) being located on the outside of the impregnation layer close to the first surface layer (4), the coating layer (8) having a thickness of 30-60 microns, and the coating layer (8) being composed of a PTFE film.

4. The process for preparing a density gradient PPS fiber filter material according to claims 1-3, characterized in that: The method comprises the following steps: S1: preparing a base fabric layer (5), wherein fine-denier PPS fibers and fine-denier stainless steel fibers are twisted together to form warp and weft threads and then woven into a base fabric; S2: preparing a micro-denier PPS layer, a fine-denier PPS fiber layer, and a medium-denier PPS fiber layer in a mass ratio of (1-2): (2-4): (1-3) air-laid to preform a first surface layer; preparing a second surface layer by air-laid coarse-denier PPS fibers of (1.5-2.0D); S3: placing a preformed first surface layer (4) and a preformed second surface layer (6) on the upper surface and the lower surface of the base fabric layer (5), respectively, and forming a filter fabric by needle punching; S4: calendering and singeing the filter fabric, and then placing the filter fabric in an impregnation liquid for impregnation; S5: The impregnated filter fabric is subjected to high temperature shaping treatment to prepare a filter material.

5. The process for preparing a density gradient PPS fiber filter material according to claim 4, characterized in that: The impregnation liquid in S4 comprises polytetrafluoroethylene emulsion, ethanol and methyl silicone oil, the ratio of polytetrafluoroethylene emulsion, ethanol and methyl silicone oil is (12-16): (10-20): (20-40), and the residence time of the impregnation liquid is 0.5-2s.

6. The process for preparing a density gradient PPS fiber filter material according to claim 5, characterized in that: The shaping treatment in S5 is carried out in three temperature intervals of 100-150°C, 150-200°C and 160-180°C from the inlet to the outlet, and the ratio of 100-150°C, 150-200°C and 160-180°C to the shaping time is 1:(2-3):(0.5-1).

7. The process for preparing a PPS fiber filter material with a gradient density according to claim 6, characterized in that: In S3, the needling process comprises a needling density of 100-300 needles / , wherein the pre-needling stage is 100-150 needles / , and the main needling stage is 150-300 needles / .

8. A filter bag made of PPS fiber filter material with gradient density, made according to any one of the preparation processes of claims 4-6, characterized in that: The invention comprises a filter bag body; the filter bag body comprises a cylinder (9) and a bag bottom (10); the cylinder body is formed by sewing the filter material through a first suture thread, the first suture thread is one or more of a PPS fiber thread, a PTFE fiber thread, and a 316L metal fiber thread; the bag bottom (10) and the cylinder (9) are sewn through a second suture thread, the second suture thread is one or more of a PPS fiber thread, a PTFE fiber thread, and a 316L metal fiber thread; the outer surfaces of the first suture thread and the second suture thread are also provided with a protective layer, the protective layer being any one of silicone and hot melt adhesive.

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