A filter with replaceable ceramic membrane, its preparation method and its usage method

Abstract

The present invention relates to a ceramic membrane material, in particular to a filter with replaceable ceramic membranes, a preparation method thereof and a usage method thereof. A filter with replaceable ceramic membranes includes a support body and a ceramic membrane disposed on the outer surface of the support body. The ceramic membrane is formed by adsorbing a slurry on the surface of the support body by creating a negative pressure in the cavity of the support body, and the ceramic membrane does not require heat treatment and can be regenerated. This ceramic membrane material does not require heat treatment, is easy to regenerate, can be used for filtering high-viscosity materials, and reduces the production cost and usage cost of the ceramic membrane.

Description

Technical Field

[0001] The present invention relates to a ceramic membrane material, in particular to a filter with a replaceable ceramic membrane, a preparation method thereof and a usage method thereof. Background Art

[0002] In recent decades, due to its high-efficiency separation performance, ceramic membranes have been increasingly widely used in various industries and have become the choice in multiple industries such as biology, chemical engineering, energy, and environmental protection. However, ceramic membrane materials are expensive, and the preparation process is complex, usually requiring firing more than twice. Moreover, during use, they are easily blocked, resulting in the failure of the membrane material, greatly increasing the use cost of the ceramic membrane. When dealing with high-viscosity materials and materials with a relatively high colloid content, the membrane material will be blocked very quickly. It is possible that after one suction filtration, the high-viscosity material will adsorb on the membrane material and cannot be restored even by backwashing, which makes the membrane material inapplicable to these working conditions in terms of economy and efficiency. Summary of the Invention

[0003] To solve the above problems, the present invention provides a filter with a replaceable ceramic membrane and low cost. The specific technical solution is as follows:

[0004] A filter with a replaceable ceramic membrane includes a support body and a ceramic membrane disposed on the outer surface of the support body. The ceramic membrane is formed by creating a negative pressure in the cavity of the support body to adsorb the slurry on the surface of the support body to form the ceramic membrane. The ceramic membrane does not require heat treatment and can be regenerated.

[0005] Preferably, the support body is made of the following materials according to mass parts: 50 - 90 parts of aggregate; 10 - 30 parts of clay powder; 5 - 10 parts of talc powder; 5 - 10 parts of calcium carbonate powder; 0.5 - 2 parts of polyvinyl alcohol; 70 - 120 parts of water.

[0006] Further, the aggregate is one of alumina, silicon carbide, silicon oxide, and titanium oxide.

[0007] Preferably, the particle size of the aggregate is 2 - 25 times the filtration accuracy.

[0008] Preferably, when the total weight of the aggregate, clay powder, talc powder, and calcium carbonate powder is 100 parts; 0.5 - 2 parts of polyvinyl alcohol; 70 - 120 parts of water.

[0009] Further, the ceramic membrane is made of the following materials according to mass parts: 60 - 90 parts of aggregate; 10 - 40 parts of clay powder; 0.2 - 0.5 parts of sodium carboxymethyl cellulose; 100 - 400 parts of water.

[0010] Among them, the particle size of the aggregate is 1-5 times the filtration accuracy; when the total weight of the aggregate and clay powder is 100 parts; 0.2-0.5 parts of sodium carboxymethyl cellulose; 100-400 parts of water.

[0011] A preparation method of a filter with a replaceable ceramic membrane, the filter with a replaceable ceramic membrane includes the following preparation steps:

[0012] 1) Spray granulation to prepare the support raw material, add the aggregate, clay, talc, calcium carbonate and water into the ball mill, the material-ball ratio is 1:1, after ball milling, add polyvinyl alcohol, continue ball milling, and then spray granulation to make the raw material;

[0013] 2) Pressurized molding to press into a support blank with a cavity;

[0014] 3) Firing, firing in a kiln, the firing temperature is 1100-1400 °C;

[0015] 4) Grinding process, through grinding process to make a support with a smooth surface and a cavity;

[0016] 5) Membrane slurry preparation, add the aggregate, clay, sodium carboxymethyl cellulose and water into the ball mill for ball milling;

[0017] 6) Membrane layer adsorption, form a negative pressure in the cavity of the support, immerse it into the membrane slurry, take it out after adsorption.

[0018] A use method of a filter with a replaceable ceramic membrane, including the following steps:

[0019] 1) Filtration, immerse the filter with the adsorbed membrane layer into the material to be filtered until the filter cake layer no longer thickens, take out the filter from the material to be filtered, among which, the cavity of the support maintains a negative pressure throughout the process;

[0020] 2) Backwashing, after taking out the filter, use compressed air or water to backwash the filter cake and the membrane layer together into the recovery device, and the flux of the support is restored;

[0021] 3) Membrane layer adsorption, form a negative pressure in the cavity of the support, immerse it into the membrane slurry, take it out after adsorption, and a ceramic membrane is formed on the outer surface of the support.

[0022] Preferably, it is used for filtering high-viscosity materials.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] A filter with replaceable ceramic membranes provided by the present invention is applied to the filtration of high-viscosity materials or materials with a high colloid content. By adsorbing on the surface of the support to form a membrane layer, heat treatment is not required. After the filtration process, the retained materials and the membrane layer are blown off together by backwashing, enabling the complete regeneration of the support. The support can then form a replaceable ceramic membrane again by adsorption on its surface.

[0025] It solves the problem of difficult filtration of high-viscosity materials; moreover, the production cost of the filter with replaceable ceramic membranes is relatively low. Firstly, it uses inexpensive particles such as silica and alumina as the main materials for membrane preparation. Secondly, the membrane material does not require firing. Thirdly, the support can be reused repeatedly, effectively reducing the usage cost of the membrane material. Description of the Drawings

[0026] Figure 1 It is a schematic diagram of a tubular support;

[0027] Figure 2 It is a cross-sectional view of a disc-shaped support. Detailed Embodiments

[0028] The present invention will now be further described in conjunction with the accompanying drawings.

[0029] A filter with replaceable ceramic membranes includes a support and a ceramic membrane provided on the outer surface of the support. The ceramic membrane forms a negative pressure in the cavity of the support to adsorb the slurry on the surface of the support to form a ceramic membrane, and the ceramic membrane does not require heat treatment and is renewable.

[0030] The replaceable ceramic membrane material includes the following preparation steps:

[0031] 1) Spray granulation to prepare the support raw material. Add aggregate, clay, talc, calcium carbonate and water into a ball mill, with a material-to-ball ratio of 1:1, ball mill for 2 - 6 h, add polyvinyl alcohol, and ball mill for 5 - 10 min, then spray granulate to make the raw material.

[0032] 2) Press molding. Press into a support blank with a cavity by a hydraulic press or an isostatic press, etc.

[0033] 3) Firing. Conduct firing in a kiln, and the firing temperature is between 1100 - 1400 °C.

[0034] 4) Grinding process. Make a qualified support with a cavity through grinding.

[0035] 5) Membrane slurry preparation. Add aggregate, clay, sodium carboxymethyl cellulose and water into a ball mill, with a material-to-ball ratio of 1:1, and ball mill for 2 - 6 h.

[0036] 6) Membrane layer adsorption. Form a negative pressure in the cavity of the support, immerse it in the membrane slurry, take it out after adsorption for 1 - 10 s.

[0037] Example 1

[0038] As Figure 1 shown, Preparation and Application of Porous Tubular Replaceable Silicon Carbide Ceramic Membrane Material

[0039] Preparation:

[0040] 1) Prepare the support raw material by spray granulation. Add 70 parts of silicon carbide, 10 parts of clay, 10 parts of talc, 10 parts of calcium carbonate and 100 parts of water into a ball mill, with a material-to-ball ratio of 1:1. Ball mill for 6 h, add 2 parts of polyvinyl alcohol, and ball mill for 10 min, then spray granulate to make the raw material; the average particle size of silicon carbide is 20 microns;

[0041] 2) Press into a circular tubular blank by a dry isostatic press.

[0042] 3) Fire. Fire in a kiln at a firing temperature of 1400 °C and hold for 2 hours;

[0043] 4) Grinding process. Grind the outer circle of the support by an external cylindrical grinder to make a support with a smooth surface;

[0044] 5) Prepare the membrane slurry. Add 90 parts of silicon carbide, 10 parts of clay, 0.2 part of sodium carboxymethyl cellulose and 100 parts of water into a ball mill, with a material-to-ball ratio of 1:1. Ball mill for 6 h to make the slurry, where the average particle size of silicon carbide is 5 microns;

[0045] 6) Membrane layer adsorption. Seal one end of the porous circular tube support and leave the other end open. Form a negative pressure in the cavity by a vacuum pump, then immerse it in the membrane slurry and take it out after adsorption for 1 s.

[0046] Application

[0047] 7) Filtration. Immerse the support with the adsorbed membrane layer into the material to be filtered until the filter cake layer no longer thickens (when the filtration flux is close to 0), and take out the membrane material from the material to be filtered. Keep a negative pressure in the cavity of the support throughout the process;

[0048] 8) Backwashing; After taking out, use compressed air or water to backwash the filter cake and the membrane layer together into the recovery facility, and the flux of the support can be restored;

[0049] 9) Repeat the operations of 6, 7, and 8 to realize the replacement and application of the membrane layer.

[0050] Example 2

[0051] Preparation and Application of Porous Tubular Replaceable Alumina Ceramic Membrane Material

[0052] Preparation:

[0053] 1) Preparation of the support raw material by spray granulation: Add 60 parts of alumina, 30 parts of clay, 5 parts of talc, 5 parts of calcium carbonate and 70 parts of water into a ball mill. The ratio of material to balls is 1:1. Ball mill for 6 h, add 0.5 part of polyvinyl alcohol, and ball mill for 5 min. Then, make the raw material by spray granulation. Among them, the average particle size of alumina is 50 microns;

[0054] 2) Press into a tubular green body by a dry isostatic press;

[0055] 3) Firing; Fire in a kiln. The firing temperature is 1100 °C and hold for 2 hours;

[0056] 4) Grinding process: Grind the outer circle of the support by an external cylindrical grinder to make a support with a smooth surface;

[0057] 5) Preparation of the membrane slurry. Add 60 parts of alumina, 40 parts of clay, 0.5 part of sodium carboxymethyl cellulose and 150 parts of water into a ball mill. The ratio of material to balls is 1:1. Ball mill for 2 h to make a slurry. Among them, the average particle size of alumina is 10 microns;

[0058] 6) Membrane layer adsorption; Seal one end of the porous tubular support and leave the other end open. As shown in the figure, form a negative pressure in the cavity through a vacuum pump, and then immerse it in the membrane slurry. Take it out after adsorption for 10 s. Figure 1 As shown, a negative pressure is formed in the cavity by a vacuum pump, and then it is immersed in the membrane slurry and taken out after 10 s of adsorption.

[0059] Application

[0060] 7) Filtration; Immerse the support with the adsorbed membrane layer into the material to be filtered until the filter cake layer no longer thickens (when the filtration flux is close to 0), take out the membrane material from the material to be filtered, and keep a negative pressure in the cavity of the support during the whole process;

[0061] 8) Backwashing: After taking it out, use compressed air or water to backwash the filter cake and the membrane layer together into the recovery facility, and the flux of the support can be restored;

[0062] 9) Repeat the operations of 6, 7, and 8 to realize the replacement and application of the membrane layer.

[0063] Example 3

[0064] Preparation and application of a disk-type replaceable alumina ceramic membrane material

[0065] Preparation

[0066] 1) Preparation of the support raw material by spray granulation: Add 65 parts of alumina (average particle size 3 microns), 20 parts of clay, 5 parts of talc, 10 parts of calcium carbonate and 120 parts of water into a ball mill. The ratio of material to balls is 1:1. Ball mill for 6 h, add 1 part of polyvinyl alcohol, and ball mill for 10 min. Then, make the raw material by spray granulation.

[0067] 2) A disc-shaped ceramic membrane support having a hollow structure is formed by dry pressing with a hydraulic press, such as Figure 2 As shown;

[0068] 3) Firing: Firing is carried out in a kiln at a temperature of 1250°C for 2 hours;

[0069] 4) Grinding: grinding the surface of the support body by a surface grinder to produce a disc-type ceramic membrane support body with a smooth surface;

[0070] 5) Preparation of membrane slurry: 90 parts of alumina (average particle size 0.2 μm), 10 parts of clay, 0.3 parts of sodium hydroxymethyl cellulose and 400 parts of water were added into a ball mill with a material-ball ratio of 1:1, and the mixture was ball milled for 6 hours to prepare a slurry;

[0071] 6) Membrane adsorption: vacuum is drawn through the holes at the inner diameter of the disc-type ceramic membrane support to form a negative pressure in the cavity inside the support, and then the support is immersed in the membrane slurry and taken out after adsorption for 5 seconds.

[0072] application

[0073] 7) Filtration, immersing the support body with the adsorbed membrane layer into the material to be filtered until the filter cake layer no longer thickens (when the filtration flux is close to 0), and then taking the membrane material out of the material to be filtered. During the whole process, the cavity of the support body is kept at negative pressure;

[0074] 8) Backflush: After taking out, use compressed air or water to backflush the filter cake and membrane layer to the recovery facility, and the support can restore the flux;

[0075] 9) Repeat steps 6, 7, and 8 to replace and apply the film layer.

[0076] The technical principle of the present invention is described above in conjunction with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the protection scope of the present invention in any way. Based on the explanations herein, those skilled in the art can associate other specific implementations of the present invention without paying creative labor, and these methods will fall within the protection scope of the claims of the present invention.

Claims

1. A filter with replaceable ceramic membrane, characterized in that, It includes a support body and a ceramic membrane arranged on the outer surface of the support body, wherein the ceramic membrane forms a negative pressure in the cavity of the support body, adsorbs the slurry on the surface of the support body to form a ceramic membrane, and the ceramic membrane does not need heat treatment and can be regenerated; The ceramic membrane is made of the following materials in parts by mass: 60-90 parts of aggregate; 10-40 parts of clay powder; 0.2-0.5 parts of sodium hydroxymethyl cellulose; 100-400 parts of water.

2. The filter with replaceable ceramic membrane according to claim 1, characterized in that, The support is made of the following materials in parts by mass: 50-90 parts of aggregate; 10-30 parts of clay powder; 5-10 parts of talcum powder; 5-10 parts of calcium carbonate powder; 0.5-2 parts of polyvinyl alcohol; and 70-120 parts of water.

3. The filter with replaceable ceramic membrane according to claim 2, characterized in that, The aggregate is one of aluminum oxide, silicon carbide, silicon oxide and titanium oxide.

4. The filter with replaceable ceramic membrane according to claim 2, characterized in that, The particle size of the aggregate is 2-25 times the filtering accuracy.

5. The filter with replaceable ceramic membrane according to claim 2, wherein, When the total weight of the aggregate, clay powder, talcum powder and calcium carbonate powder is 100 parts, the polyvinyl alcohol is 0.5-2 parts, and the water is 70-120 parts.

6. The filter with replaceable ceramic membrane according to claim 5, characterized in that, The particle size of the aggregate is 1-5 times the filtration accuracy; When the total weight of the aggregate and clay powder is 100 parts, the sodium hydroxymethyl cellulose is 0.2-0.5 parts, and the water is 100-400 parts.

7. The preparation method of a filter with replaceable ceramic membrane according to claim 2, characterized in that, The filter with replaceable ceramic membrane comprises the following preparation steps: 1) Prepare the support material by spray granulation. Add aggregate, clay, talc, calcium carbonate and water into a ball mill with a material-ball ratio of 1:

1. Add polyvinyl alcohol after ball milling, continue ball milling, and then spray granulate to obtain the raw material; 2) Pressing and forming to form a support body blank with a cavity; 3) Firing: Firing is carried out in a kiln at a temperature of 1100-1400°C; 4) Grinding, through which a support body with a smooth surface and a cavity is produced; 5) Preparation of membrane slurry: add aggregate, clay, sodium hydroxymethyl cellulose and water into a ball mill for ball milling; 6) The membrane layer is adsorbed, forming a negative pressure in the cavity of the support body, immersed in the membrane slurry, and taken out after adsorption.

8. The usage method of a filter with replaceable ceramic membranes according to claim 1, characterized in that, The following steps are involved: 1) Filtration: immerse the filter with the adsorbed membrane layer into the material to be filtered until the filter cake layer no longer thickens, and then take the filter out of the material to be filtered. During the whole process, the cavity of the support body maintains negative pressure; 2) Backflush: After taking out the filter, use compressed air or water to backflush the filter cake and membrane layer into the recovery device to restore the flux of the support body; 3) The membrane layer is adsorbed, a negative pressure is formed in the cavity of the support body, and it is immersed in the membrane slurry. After adsorption, it is taken out and a ceramic membrane is formed on the outer surface of the support body.

9. The method for using a filter with replaceable ceramic membranes according to claim 8, characterized in that, Used for filtering high viscosity materials.

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