High-temperature-resistant and wear-resistant filter material for pulverized coal collector and preparation method thereof

Abstract

The invention relates to a high-temperature-resistant and wear-resistant filter material for a pulverized coal collector and a preparation method of the high-temperature-resistant and wear-resistant filter material. The preparation method comprises the following steps: soaking a plain felt in a graphene glue solution in a flowing manner, so that the plain felt contains graphene fine particles; then carrying out oven curing treatment to cure the graphene fine particles on the surface of the plain felt fiber; then carrying out hot roll compacting and flattening treatment; finally, a PTFE film is attached to the upper surface of the plain felt, then the PTFE film and the plain felt are heated together through a high-temperature roller, the PTFE film and the plain felt are bonded, and the PTFE film and the plain felt are firmly combined through pressurization. The filter material is prepared by the preparation method. The filter material is excellent in air permeability and small in resistance, the energy consumption of a pulverized coal collector is reduced, the fine filtration PTFE film layer is firmly bonded, and the fine filtration PTFE film layer does not fall off when being pressed in the using process.

Description

Technical Field

[0001] The invention relates to a high temperature and wear resistant filter material for a coal powder collector and a preparation method thereof, belonging to the technical field of filter bag materials for coal chemical industry coal gas filtration. Background Art

[0002] The petrochemical industry is developing rapidly, and the consumption of petroleum for producing petrochemical products is increasing rapidly. my country is a country with a shortage of oil, little gas, and relatively abundant coal. The development of coal chemical industry to produce petrochemical products such as ethylene, propylene, and ethylene glycol can reduce the consumption of chemical light oil and indirectly replace oil. The development of a modern coal chemical industry is of great strategic significance for ensuring my country's energy security, reducing dependence on oil imports, promoting energy structure adjustment, and accelerating industrial independent innovation and high-tech development and application.

[0003] Coal chemical industry and coal-to-liquids are the substitution of one fossil energy source for another. Coal gasification technology is the key to the development of coal chemical industry. my country's coal gasification technology has developed rapidly, and a number of coal gasification technologies with independent intellectual property rights have been developed. The threat to the environment from coal chemical industry (coal-to-liquids) mainly comes from the waste gas, dust and toxic gas generated, high-concentration sewage, ammonium sulfate sewage, oily sewage, salty sewage and waste residue discharged. If not properly controlled, the discharge will cause serious harm to the environment.

[0004] In coal chemical production, the quality of raw coal is one of the three major factors that restrict the stable operation of gasification equipment, just as important as equipment and electrical instruments. Usually in the pulverized coal preparation process, after the raw coal and flux enter the pulverizer together, under the rolling of the grinding rollers and the blowing of hot circulating gas, small particles of coal powder are entrained by the gas and pass upward through the flow channel of the rotary separator and enter the pulverized coal collector. The collected pulverized coal is pressurized and transported into the gasifier to participate in the reaction. In this process, due to frequent leakage of the pulverized coal collector, it is necessary to frequently switch the pulverizer back and forth between the main and standby machines. The main reason for the frequent leakage of the pulverized coal collector is that the filter bags used are often damaged, resulting in coal powder leakage, which not only leads to increased loss of raw materials, but also pollutes the environment.

[0005] At present, the main materials of filter bags for coal dust collectors include polyester antistatic filter materials, acrylic antistatic filter materials, PPS antistatic filter materials, and composite fiber antistatic filter materials. Due to the material properties of the filter materials, processing technology, and working conditions of the coal dust collector, the service life of the filter bags varies. The filter bags for coal dust collectors are often damaged, resulting in frequent shutdowns, which seriously affects the continuous and stable production and operation of coal gasification. Summary of the invention

[0006] In order to solve the above problems, the present invention discloses a high temperature and wear resistant filter material for a coal powder collector and a preparation method thereof, and the specific technical scheme thereof is as follows:

[0007] A method for preparing a high temperature resistant and wear resistant filter material for a coal powder collector comprises the following steps:

[0008] Step 1: Flow impregnation operation: After the plain felt (11) is flow-impregnated with the graphene glue (12), the surface of the plain felt (11) contains graphene fine particles;

[0009] Step 2: Oven curing treatment: the plain felt (11) treated in step 1 enters the oven (13), and after high temperature treatment in the oven (13), the graphene fine particles are cured on the fiber surface of the plain felt (11);

[0010] Step 3: Hot rolling and flattening treatment: the plain felt (11) treated in step 2 is placed between two upper and lower hot rolling rollers (14) for rolling under pressure and heating, so that the dense pores inside the plain felt (11) are reduced and the surface is flat;

[0011] Step 4: PTFE membrane bonding and reinforcement treatment: The plain felt (11) treated in step 2 continues to move downstream, and the PTFE membrane (15) is bonded to its upper surface, and then they are heated together by a high-temperature roller (16) to bond the PTFE membrane (15) and the plain felt (11). A rubber roller (17) is arranged under the high-temperature roller (16). The high-temperature roller (16) and the rubber roller (17) are relatively pressurized to firmly bond the PTFE membrane (15) and the plain felt (11).

[0012] Furthermore, the components and their mass proportions in the graphene glue in step 1 are: graphene: 28% to 65%, binder: 5% to 20%, dispersant: 5% to 15%, organic solvent: 5% to 25%, and deionized water: 5% to 25%.

[0013] Furthermore, the graphene glue is also added with conductive carbon black, and the total proportion of the mixture of graphene and conductive carbon black in the graphene glue is 30% to 70%.

[0014] Furthermore, when the immersion time of the plain felt (11) is 5 to 15 minutes, the graphene fine particles are evenly attached to the surface of the felt.

[0015] Furthermore, the plain felt (11) comprises a support layer (1), an antistatic base fabric layer (2) and a coarse filter layer (3) in sequence, and the coarse filter layer (3) is bonded to a PTFE membrane (15);

[0016] The support layer (1) is composed of PPS fibers randomly connected;

[0017] The antistatic base fabric layer (2) is woven from PPS yarns with one stainless steel fiber yarn interlaced at a distance of 10 to 15 cm;

[0018] The coarse filter layer (3) is composed of 0.9-1.2 dtex and 1.5-2.2 dtex PPS fibers that are randomly linked.

[0019] Furthermore, in the step 2, the oven (13) is controlled at a temperature of 100-180° C., so that the graphene fine particles are firmly solidified on the fiber surface of the plain felt (11) within 5 to 15 minutes.

[0020] Furthermore, in step 3, the plain felt (11) passes between two hot rolling rollers (14) made of high-temperature resistant alloy steel, the extrusion pressure between the upper and lower hot rolling rollers (14) is 10MPa-20MPa, and the roller temperature is maintained at 100°C-120°C.

[0021] Furthermore, in step 4, the temperature of the high temperature roller (16) is controlled at 200°C-230°C, and the high temperature roller (16) and the rubber roller (17) provide a pressure of 10MPa-20MPa in relative extrusion.

[0022] The present invention also applies for protection of the filter material prepared by the method for preparing the high temperature resistant and wear resistant filter material for the coal powder collector.

[0023] The present invention also applies for protection of a filter bag for a coal dust collector prepared from the filter material and a coal dust collector prepared using the filter bag and / or the filter material.

[0024] The beneficial effects of the present invention are:

[0025] The present invention provides a method for preparing filter material for an ultra-low emission filter bag for a coal powder collector. The method selects excellent performance fibers and combines the advantages of gradient filter material and coated filter material to improve filtering accuracy, while also improving the filtering accuracy and extending the service life of the filter bag, so that the filter bag is suitable for ultra-low emission requirements, which not only ensures the long-term stable operation of the coal powder collector, but also reduces coal powder loss and increases economic benefits.

[0026] The filter material of the invention has excellent air permeability and small resistance, and reduces the energy consumption of the coal powder collector.

[0027] The filter material of the invention effectively eliminates friction static electricity in the coal powder collector and prevents static electricity sparks from causing dust explosions.

[0028] The fine filtration PTFE membrane layer of the invention is firmly bonded and does not fall off when subjected to pressure during use.

[0029] The fine filtration layer of the filter material of the invention has small pores and high filtration efficiency, and can effectively intercept fine coal powder particles.

[0030] The fine filter layer of the present invention is made of PTFE material, has a smooth surface and is not easy to wear, and the service life of the filter material is increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a schematic diagram of the preparation process of the present invention,

[0032] Figure 2 is a cross-sectional view of the filter material of the present invention,

[0033] List of reference numerals: 1—support layer, 2—antistatic base fabric layer, 3—coarse filtration layer, 4—adhesive layer, 5—fine filtration layer, 11—plain felt, 12—graphene glue, 13—oven, 14—hot rolling roller, 15—PTFE membrane, 16—high temperature roller, 17—rubber roller, 18—filter material. DETAILED DESCRIPTION

[0034] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0035] Combined with Figure 1 It can be seen that the preparation process of the present invention is as follows: Step 1: Flow impregnation operation: After the plain felt 11 is flow-impregnated with the graphene glue 12, the surface of the plain felt 11 contains graphene fine particles. The components and their mass proportions in the graphene glue are: graphene: 28% to 65%, binder: 5% to 20%, dispersant: 5% to 15%, organic solvent: 5% to 25%, deionized water: 5% to 25%. The graphene glue also adds conductive carbon black, and the total proportion of the graphene and conductive carbon black mixture in the graphene glue is: 30% to 70%. The plain felt 11 is impregnated for 5 to 15 minutes, and graphene fine particles are evenly attached to its surface.

[0036] The binder is selected from any one of polyvinylidene fluoride (PVDF), sodium carboxymethyl cellulose (CMC), polyacrylic acid (PAA), and styrene-butadiene rubber (SBR).

[0037] Dispersants are selected from organic polymers, such as polyacrylamide series, polyethylene oxide series and natural polymers such as tannin and lignin.

[0038] The organic solvent is selected from any one of N-methylpyrrolidone (NMP), dimethyl sulfoxide (DMSO), dimethylformamide (DMF), and γ-butyrolactone (GBL).

[0039] Step 2: Oven curing treatment: The plain felt 11 treated in step 1 enters the oven 13, and after high temperature treatment in the oven 13, the graphene fine particles are cured on the fiber surface of the plain felt 11. The oven 13 is controlled at a temperature of 100-180° C., so that the graphene fine particles are firmly cured on the fiber surface of the plain felt 11 within 5-15 minutes.

[0040] Step 3: Hot rolling and leveling treatment: The felt 11 treated in step 2 is rolled between two upper and lower hot rolling rollers 14 under pressure and heating to reduce the dense pores inside the felt 11 and level the surface; the felt 11 passes between two hot rolling rollers 14 made of high-temperature resistant alloy steel, the extrusion pressure between the upper and lower hot rolling rollers 14 is 10MPa-20MPa, and the roller temperature is maintained at 100℃-120℃.

[0041] Step 4: PTFE film lamination and reinforcement treatment: The plain felt 11 treated in step 2 continues to move downstream, and the PTFE film 15 is laminated on its upper surface, and then heated together by the high-temperature roller 16, the PTFE film 15 and the plain felt 11 are bonded, and a rubber roller 17 is arranged under the high-temperature roller 16, and the high-temperature roller 16 and the rubber roller 17 are relatively pressed to firmly bond the PTFE film 15 and the plain felt 11. The temperature of the high-temperature roller 16 is controlled at 200℃-230℃, and the high-temperature roller 16 and the rubber roller 17 are relatively squeezed to provide a pressure of 10MPa-20MPa.

[0042] Three embodiments of the method of the present invention are given below. The method steps are as above, and the process parameters controlled by each embodiment are as follows:

[0043] Table 1 Graphene glue formula components of Examples 1-3

[0044]

[0045] Table 2 Preparation process conditions of Examples 1-3

[0046]

[0047] Table 3 Performance parameters of filter materials prepared in Examples 1-3

[0048]

[0049] Combined with Figure 2 It can be seen that the structure of the filter material 18 prepared by the present invention is: from one side to the other side, it includes a support layer 1, an antistatic base fabric layer 2, a coarse filter layer 3, a bonding layer 4 and a fine filter layer 5 in sequence, and the adjacent layers are interwoven and tightly connected. The support layer 1, the antistatic base fabric layer 2 and the coarse filter layer 3 form a plain felt 11, and the fine filter layer 5 is formed by bonding a PTFE membrane 15 with the coarse filter layer 3 through a bonding layer 4. The support layer 1 is composed of PPS fibers that are randomly connected; the antistatic base fabric layer 2 is made of PPS yarns, and one stainless steel fiber yarn is interspersed at 10 to 15 cm; the coarse filter layer 3 is composed of 0.9 to 1.2 dtex and 1.5 to 2.2 dtex PPS fibers that are randomly connected.

[0050] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by those skilled in the art to which this application belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless defined as herein.

[0051] The meaning of "and / or" described in this application means that the situations where each exists alone or both exist at the same time are included.

[0052] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A method for preparing a high temperature and wear resistant filter material for a coal powder collector, characterized in that: The following steps are involved: Step 1: Flow impregnation operation: After the plain felt (11) is flow-impregnated with the graphene glue (12), the surface of the plain felt (11) contains graphene fine particles; Step 2: Oven curing treatment: the plain felt (11) treated in step 1 enters the oven (13), and after high temperature treatment in the oven (13), the graphene fine particles are cured on the fiber surface of the plain felt (11); Step 3: Hot rolling and flattening treatment: the plain felt (11) treated in step 2 is placed between two upper and lower hot rolling rollers (14) for rolling under pressure and heating, so that the dense pores inside the plain felt (11) are reduced and the surface is flat; Step 4: PTFE membrane bonding and reinforcement treatment: The plain felt (11) treated in step 2 continues to move downstream, and the PTFE membrane (15) is bonded to its upper surface, and then they are heated together by a high-temperature roller (16) to bond the PTFE membrane (15) and the plain felt (11). A rubber roller (17) is arranged under the high-temperature roller (16). The high-temperature roller (16) and the rubber roller (17) are relatively pressurized to firmly bond the PTFE membrane (15) and the plain felt (11).

2. The method for preparing the high temperature and wear resistant filter material for coal powder collector according to claim 1, characterized in that: The components and their mass proportions in the graphene glue in step 1 are: graphene: 28% to 65%, binder: 5% to 20%, dispersant: 5% to 15%, organic solvent: 5% to 25%, and deionized water: 5% to 25%.

3. The method for preparing the high temperature and wear resistant filter material for coal powder collector according to claim 2, characterized in that: The graphene glue is also added with conductive carbon black, and the total proportion of the mixture of graphene and conductive carbon black in the graphene glue is 30% to 70%.

4. The method for preparing the high temperature and wear resistant filter material for coal powder collector according to claim 2, characterized in that: The immersion time of the plain felt (11) is 5 to 15 minutes, and graphene fine particles are evenly attached to the surface of the felt.

5. The method for preparing the high temperature and wear resistant filter material for coal powder collector according to claim 1, characterized in that: The plain felt (11) comprises a support layer (1), an antistatic base fabric layer (2) and a coarse filter layer (3) in sequence, and the coarse filter layer (3) is bonded to a PTFE membrane (15); The support layer (1) is composed of PPS fibers randomly connected; The antistatic base fabric layer (2) is woven from PPS yarns with one stainless steel fiber yarn interlaced at a distance of 10 to 15 cm; The coarse filter layer (3) is composed of 0.9-1.2 dtex and 1.5-2.2 dtex PPS fibers that are randomly linked.

6. The method for preparing the high temperature and wear resistant filter material for coal powder collector according to claim 1, characterized in that: In the step 2, the oven (13) is controlled at a temperature of 100-180° C., so that the graphene fine particles are firmly solidified on the fiber surface of the plain felt (11) within 5-15 minutes.

7. The method for preparing the high temperature and wear resistant filter material for coal powder collector according to claim 1, characterized in that: In step 3, the plain felt (11) passes between two hot rolling rollers (14) made of high-temperature resistant alloy steel, the extrusion pressure between the upper and lower hot rolling rollers (14) is 10MPa-20MPa, and the roller temperature is maintained at 100°C-120°C.

8. The method for preparing the high temperature and wear resistant filter material for coal powder collector according to claim 1, characterized in that: In step 4, the temperature of the high temperature roller (16) is controlled at 200°C-230°C, and the high temperature roller (16) and the rubber roller (17) provide a pressure of 10MPa-20MPa in relative extrusion.

9. The filter material prepared by the method for preparing the high temperature resistant and wear resistant filter material for coal powder collector according to any one of claims 1 to 8.

10. A filter bag for a coal dust collector prepared using the filter material according to claim 9 and a coal dust collector prepared using the filter bag and / or the filter material.

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