Ceramic membrane assembly and ceramic membrane component

Abstract

The invention relates to a ceramic membrane assembly and a ceramic membrane assembly. The assembly comprises a plurality of ceramic membrane tubes and a plurality of ceramic connecting pieces, the cross section of the ceramic membrane tube is in a regular hexagon shape; a plurality of first runners are arranged in the ceramic membrane tube; the ceramic membrane tubes are divided into at least three membrane tube queues, and all the membrane tube queues are stacked to form a structural body with a hexagonal cross section; the ceramic membrane tubes in the same membrane tube queue are arranged side by side, and the outer wall surfaces of every two adjacent ceramic membrane tubes are attached to each other; every two adjacent membrane tube queues are connected and fixed through a ceramic connecting piece, and the ceramic connecting piece is attached to the outer wall of the adjacent ceramic membrane tube; and a second flow channel is arranged between every two adjacent membrane tube queues, and the second flow channels are communicated with the exterior of the structural body. The assembly is stable in structure and long in service life, the filling mode of the tubular ceramic membrane and the structure of matched parts can be simplified, the structure of the ceramic membrane assembly is optimized, and the cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of ceramic membranes, and in particular to a ceramic membrane assembly and a ceramic membrane component. Background Art

[0002] Ceramic membrane, also known as inorganic ceramic membrane, is an asymmetric membrane made of inorganic ceramic materials through special processes. Ceramic membranes are divided into tubular ceramic membranes and flat ceramic membranes. The wall of tubular ceramic membranes is densely covered with micropores. Under pressure, the raw liquid flows inside the membrane tube or outside the membrane, small molecules or liquids pass through the membrane, and large molecules or solids are retained by the membrane, thereby achieving the purpose of separation, concentration, purification and environmental protection.

[0003] The current filling method of tubular ceramic membrane is generally: the ceramic membrane is filled in a stainless steel membrane shell, with flanges connected at both ends of the membrane shell, and a sealing ring is used to seal the flange and the ceramic membrane. In order to ensure the sealing and filter the second flow channel, the flange and the sealing ring need to be provided with holes corresponding to the ceramic membrane. Such a connection structure makes the processing of the flange and the sealing ring difficult and the assembly is troublesome. Summary of the invention

[0004] The object of the present invention is to provide a ceramic membrane assembly and a ceramic membrane component, which have a stable structure and a long service life, and can simplify the filling method of the tubular ceramic membrane and the structure of the ceramic membrane component.

[0005] To achieve the above object, the present invention discloses a ceramic membrane assembly, which includes a plurality of ceramic membrane tubes and a plurality of ceramic connectors; The cross section of the ceramic membrane tube is a regular hexagon; a plurality of first flow channels are arranged inside the ceramic membrane tube, and the first flow channels are arranged along the length direction of the ceramic membrane tube and penetrate the ceramic membrane tube; a filter membrane layer is provided on the inner wall of the first flow channel, or a filter membrane layer is provided on the outer wall of the ceramic membrane tube; The ceramic membrane tubes are divided into at least three membrane tube rows, and all the membrane tube rows are stacked to form a structure with a hexagonal cross-section; the ceramic membrane tubes of the same membrane tube row are arranged side by side, and the outer wall surfaces of two adjacent ceramic membrane tubes fit together; two adjacent membrane tube rows are connected and fixed by ceramic connectors, and the ceramic connectors fit together with the outer walls of the adjacent ceramic membrane tubes; there is a second flow channel between two adjacent membrane tube rows, and the second flow channel connects to the outside of the structure.

[0006] Preferably, the cross-section of the first flow channel is a regular hexagon; the first flow channels are arranged in a honeycomb structure in the ceramic diaphragm tube, and the outer edge of the figure formed by the cross-sections of all the first flow channels is parallel to the outer wall of the ceramic diaphragm tube; the diameter of the inscribed circle of the ceramic diaphragm tube is equal to 40±2mm; 91 first flow channels are arranged inside the ceramic diaphragm tube, and the diameter of the inscribed circle of the first flow channel is 2.7-3.0mm; or, 127 first flow channels are arranged inside the ceramic diaphragm tube, and the diameter of the inscribed circle of the first flow channel is 2.2-2.5mm; the inner wall corners of the first flow channel are set as arc chamfers with a radius of 0.5mm.

[0007] Preferably, a filter membrane layer is provided on the inner wall of the first flow channel; the filter membrane layer comprises a first filter membrane layer and a second filter membrane layer, the first filter membrane layer is located between the second filter membrane layer and the inner wall of the first flow channel; the pore size of the first filter membrane layer is 500-2000nm, and the pore size of the second filter membrane layer is 20-200nm.

[0008] Preferably, a first sealing layer is provided on the outer walls of both ends of the ceramic membrane tube, one end of the first sealing layer is flush with the end face of the ceramic membrane tube, the first sealing layer has a width of 5-50 mm, a thickness of 50-500 μm, and a pore size of 0.5-5 μm.

[0009] Preferably, the filter membrane layer includes a first filter membrane layer and a second filter membrane layer, and the first filter membrane layer is located between the second filter membrane layer and the inner wall of the first flow channel; after the ceramic membrane tube is sintered, and the first flow channel is coated with the first filter membrane layer and dried, the first sealing layer is coated and dried, and then the first filter membrane layer and the first sealing layer are sintered uniformly.

[0010] Preferably, a second sealing layer is provided on the outside of both ends of the structure, the pore size of the second sealing layer is 20-200nm; one end of the second sealing layer is flush with the end face of the structure, the width of the second sealing layer is 5-20mm, and the thickness is 5-20μm.

[0011] Preferably, the filter membrane layer includes a first filter membrane layer and a second filter membrane layer, and the first filter membrane layer is located between the second filter membrane layer and the inner wall of the first flow channel; after the first sealing layer is sintered, the second filter membrane layer is coated on the first flow channel and dried, and then the second sealing layer is coated and dried, and then the second filter membrane layer and the second sealing layer are sintered uniformly.

[0012] Preferably, 10% of the main material of the second filter layer is added to the main material of the first filter layer to form the main material of the ceramic connector; at least three ceramic connectors are arranged between the two adjacent membrane tube arrays, and these ceramic connectors are arranged at equal intervals along the length direction of the ceramic membrane tube; the width of the ceramic connector is 3-10mm, and the thickness is 1-3mm; The ceramic connector is extruded. After the first filter membrane layer is coated and dried, the extruded ceramic connector is assembled with the ceramic membrane tube to form a structure. Then, a pressure of 100-1000N is applied to the periphery of the structure for 30-300min to make the ceramic membrane tube and the ceramic connector bonded to each other. Then, the temperature is raised to 105-130°C and kept warm for 4-10h to dry out the moisture. Then, the ceramic connector and the first filter membrane layer are sintered.

[0013] The present invention also discloses a ceramic membrane assembly, which includes a membrane shell, two flanges, two sealing rings and the above-mentioned ceramic membrane assembly, wherein the ceramic membrane assembly is placed in the inner cavity of the membrane shell; the flange is detachably connected to the end of the membrane shell, and the sealing ring seals the gap between the flange and the ceramic membrane assembly; one of the flanges is provided with a first inlet, the other flange is provided with a first outlet, and the membrane shell is provided with a second inlet and a second outlet, the first inlet, the first flow channel and the first outlet are connected in sequence, and the second inlet and the second outlet are both connected to the inner cavity of the membrane shell.

[0014] Preferably, the shapes of the first inlet and the first outlet are adapted to the outer shape of the structure, and the sealing ring is provided with a through hole adapted to the outer shape of the structure.

[0015] The present invention has the following beneficial effects: 1. Combining several ceramic membrane tubes into a ceramic membrane assembly can greatly simplify the loading method, making loading more convenient and quick. The structure of the matching sealing rings, flanges and other components can be simplified, making them easy to process, install and maintain, and can also reduce the use of materials such as stainless steel.

[0016] 2. The arrangement of the ceramic membrane assembly of the present invention can make the ceramic membrane tubes stacked at a high density, and the cross-sectional area of ​​the assembly is smaller. Correspondingly, the diameter of the membrane shell can be set smaller, and the accumulated cavities in the membrane shell are fewer, which can reduce the amount of cleaning liquid used during cleaning and the corresponding cleaning liquid discharge pollution.

[0017] 3. The second flow channel formed by connecting the membrane tube queue through ceramic connectors can reduce the dialysis resistance, increase the filtration flux of the feed liquid, and also facilitate backwashing from the dialysis end after contamination.

[0018] 4. The wall thickness of the first flow channel of the ceramic membrane tube of the present invention is basically consistent, so that the pressure of each part during extrusion molding can be basically consistent, the extrusion stress is consistent, the density and uniformity of the green body after molding are consistent, and the green body can be dried and shrunk evenly. Compared with the uneven shape of a circular first flow channel cross-section, or a hexagonal first flow channel cross-section but a circular membrane tube cross-section, the green body qualification rate and the product compressive rupture strength can be improved. The ceramic membrane tube consumes less raw materials, and the cross-sectional area of ​​the filtration membrane per square meter is smaller.

[0019] 5. The membrane tube queue is fixedly connected by ceramic connectors, and the ceramic connectors are made of the same material as the main body of the filter layer. The overall ceramic assembly has better acid and alkali corrosion resistance, consistent or close temperature expansion coefficients, and is overall stable and durable, with a longer service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of a ceramic membrane assembly according to Example 1.

[0021] Figure 2 This is a schematic diagram of the ceramic membrane assembly of Example 1 after hiding the top ceramic membrane tube.

[0022] Figure 3 Schematic diagram of the end surface of the ceramic membrane assembly of Example 1.

[0023] Figure 4 for Figure 3 Cross-sectional view along the A axis.

[0024] Figure 5 This is a schematic diagram of the end face of the ceramic membrane tube of Example 1.

[0025] Figure 6 for Figure 5 Enlarged schematic diagram of part B in the middle.

[0026] Figure 7 FIG. 1 is a schematic diagram of a ceramic connector according to the first embodiment.

[0027] Figure 8 Schematic diagram of the ceramic membrane assembly of Example 2.

[0028] Fig. 9 It is a schematic diagram of the decomposition of the ceramic membrane assembly of the present invention.

[0029] Fig.10 Comparison of different types of ceramic membrane tubes Figure 1 .

[0030] Fig.11 Comparison of different types of ceramic membrane tubes Figure 2 .

[0031] Note: The second sealing layer is thickened.

[0032] Main component symbols: Ceramic membrane tube 1, first flow channel 2, first filter layer 3, second filter layer 4, first sealing layer 5, ceramic connector 6, second sealing layer 7, second flow channel 8, membrane shell 9, ceramic membrane assembly 10, flange 11, sealing ring 12. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0034] Embodiment 1 like Figure 1-7 As shown, this embodiment discloses a ceramic membrane assembly 10, which includes a plurality of ceramic membrane tubes 1 and a plurality of ceramic connectors 6, and the cross section of the ceramic membrane tube 1 is a regular hexagonal deformation. The ceramic membrane tube 1 is divided into at least three membrane tube queues (non-equally divided), and the ceramic membrane tubes 1 of the same membrane tube queue are arranged side by side, that is, the ceramic membrane tubes 1 of the same membrane tube queue are on the same plane and parallel to each other, and at the same time, the outer wall surfaces of the ceramic membrane tubes 1 adjacent to each other are fitted together. All the membrane tube queues are stacked to form a structure with a hexagonal cross section, and the membrane tube queues adjacent to each other are connected by ceramic connectors 6. 5-10 ceramic connectors 6 can be provided between the membrane tube queues adjacent to each other, and these ceramic connectors 6 are arranged at equal intervals along the length direction of the ceramic membrane tube 1. Because of the arrangement of the ceramic connector 6, a second flow channel 8 is formed between the membrane tube queues adjacent to each other, and the second flow channel 8 is connected to the outside of the structure. The ceramic connector 6 and the outer wall of the adjacent ceramic membrane tube 1 are fitted together and sintered and fixed, and such an arrangement can integrate several ceramic membrane tubes 1 into a combination. In this case, 19 ceramic membrane tubes 1 are used as an example for explanation, and correspondingly, there are five membrane tube rows. In this case, the ceramic connector 6 is arranged in a zigzag shape, that is, one ceramic connector 6 can simultaneously connect all the ceramic membrane tubes 1 adjacent to it, and the ceramic connector 6 arranged in this way is assembled more quickly. The length and number of teeth of the ceramic connector 6 are adaptively adjusted according to the number of ceramic membrane tubes 1 adjacent to it.

[0035] In this case, the cross section of the ceramic membrane tube 1 is a regular hexagon with an inscribed circle diameter equal to 40±1mm. There are 127 first flow channels 2 inside the ceramic membrane tube 1. These first flow channels 2 are arranged along the length direction of the ceramic membrane tube 1 and penetrate the ceramic membrane tube 1. The cross section of the first flow channel 2 is a regular hexagon, and the inscribed circle diameter of the regular hexagon is 2.2-2.5mm. As an alternative, the number of first flow channels 2 is 91, and the inscribed circle diameter of the first flow channel 2 is 2.7-3.0mm. The inner wall corners of the first flow channel 2 are set as arc chamfers with a radius of 0.5mm (from the cross-sectional figure, that is, the corners of the regular hexagon are set as arc chamfers with a radius of 0.5mm) to facilitate extrusion molding. These first flow channels 2 are arranged in a honeycomb structure in the ceramic membrane tube 1, and the outer edges of the figures formed by the cross sections of all the first flow channels 2 are parallel to the outer wall of the ceramic membrane tube 1. In this way, all the first flow channels 2 are arranged in mirror symmetry in the ceramic membrane tube 1. Moreover, after such setting, the wall thickness of the first flow channel 2 is basically consistent, the pressure of each part during extrusion molding is basically consistent, the density and uniformity of the green body after molding are consistent, the extrusion stress is consistent, the drying shrinkage is uniform, and the green body qualification rate can be increased by 10%, and the product compressive rupture strength can be increased by 20 bar.

[0036] A filter membrane layer is provided on the inner wall of the first flow channel 2, and the thickness of the filter membrane layer is 5-40 μm. The pore size of the filter membrane layer is set in a gradient. Specifically, the filter membrane layer includes a first filter membrane layer and a second filter membrane layer, and the first filter membrane layer is located between the second filter membrane layer and the inner wall of the first flow channel 2. The pore size of the first filter membrane layer is 500-2000 nm; the pore size of the second filter membrane layer is 20-200 nm.

[0037] A first sealing layer 5 is provided on the outer walls of both ends of the ceramic membrane tube 1. One end of the first sealing layer 5 is flush with the end surface of the ceramic membrane tube 1. The first sealing layer 5 has a width of 5-50 mm, a thickness of 50-500 μm, and a pore size of 0.5-5 μm.

[0038] The ceramic connecting member 6 has a width of 3-10 mm, a thickness of 1-3 mm, and a pore size of 0.5-5 μm.

[0039] In addition, a second sealing layer 7 is provided on the outside of both ends of the structure, one end of the second sealing layer 7 is flush with the end surface of the structure, the width of the second sealing layer 7 is 5-50 mm, the thickness is 50-500 μm, and the pore size is 20-200 nm.

[0040] The method for preparing the ceramic membrane assembly 10 comprises the following steps: S1. Mix 100 parts of α-alumina powder with a particle size of 20-45 μm, 10-30 parts of α-alumina powder with a particle size of 0.5-2.5 μm, 2-6 parts of a binder, 1-3 parts of a lubricant and 15-30 parts of water in proportion by mass, and extrude the green ceramic membrane tube 1 through a die, and dry the green ceramic membrane tube 1 at 105°C.

[0041] S2. Put the dried ceramic membrane tube 1 embryo into a kiln, raise the temperature to 1500-1750° C., and keep the temperature for 2-6 hours, so as to sinter the ceramic membrane tube 1.

[0042] S3, 10-20 parts by mass of α-phase alumina powder with a particle size of 0.5-2.5 μm, 1-2 parts of an organic binder and 100 parts of water are uniformly stirred to form a coating liquid with a viscosity of 50-500 centipoise, the coating liquid is applied to the first flow channel 2 of the ceramic membrane tube 1, and the water is dried at 105° C. This step obtains an unsintered first filter membrane layer.

[0043] S4, 20-35 parts of α-phase alumina powder with a particle size of 0.5-2.5 μm, 1-5 parts of α-phase alumina powder with a particle size of 0.05-0.3 μm, 1-2 parts of organic binder and 100 parts of water are mixed uniformly by mass to form a sealing liquid with a viscosity of 500-1000 centipoise, and the coating liquid is applied to the outside of both ends of the ceramic membrane tube 1, and the water is dried at 105° C. This step obtains the unsintered first sealing layer 5.

[0044] S5. Mix 100 parts of α-alumina powder with a particle size of 0.5-2.5 μm, 2-5 parts of a binder and 10-15 parts of water by mass, and extrude the green ceramic connector 6 through a die. The ceramic connector 6 uses the same main material (α-alumina powder) as the filter membrane layer, so that the setting of the ceramic connector 6 does not affect the filtering effect, or reduces the influence of the setting of the ceramic connector 6 on the filtering effect. In addition, the ceramic connector 6 is also the same as the main material of the ceramic membrane tube (α-alumina powder), and the two are easier to sinter together, and the connection reliability is better.

[0045] S6, stack the ceramic membrane tubes 1 processed in step S4 into a structure with a hexagonal cross section, and pad the ceramic connector 6 embryo between the adjacent layers of ceramic membrane tubes 1. Then, apply a pressure of 100-1000N on the periphery of the structure for 30-300min, so that the ceramic membrane tube 1 and the ceramic connector 6 embryo are bonded to each other, and then the temperature is raised to 105-130℃ and kept warm for 4-10h to dry the moisture. At this time, in the same membrane tube queue, the first sealing layer 5 on the adjacent ceramic membrane tubes 1 will also be closely attached to each other and sintered and fixed, and between the adjacent membrane tube queues, the gap can be sealed by the ceramic connector at the end position, so when looking along the length direction of the ceramic membrane tube 1, only the first flow channel 2 can be seen at the end of the structure, so when the end of the structure cooperates with the sealing ring 12, the through holes on the flange 11 and the sealing ring 12 only need to be adapted to the shape of the structure, and the through holes on the flange 11 and the sealing ring 12 do not need to be set as a honeycomb, thereby simplifying the structure of the flange 11 and the sealing ring 12.

[0046] S7, putting the dried structure into a kiln, heating it to 1400-1500°C, and keeping it warm for 2-6 hours. At this time, the structure is sintered into a whole, the ceramic connector 6 green embryo is sintered into the ceramic connector 6, and the first filter membrane layer and the first sealing layer 5 are also sintered.

[0047] S8, 10-20 parts by mass of α-phase alumina powder or zirconia powder with a particle size of 0.05-0.4 μm, 1-2 parts of an organic binder and 100 parts of water are uniformly stirred to form a coating liquid with a viscosity of 50-800 centipoise, and the coating liquid is applied to the first flow channel 2 of the ceramic membrane tube 1 of the sintered structure, and the water is dried at 105° C. At this time, an unsintered second filter membrane layer is obtained.

[0048] S9, pour the coating liquid in step S8 onto the ceramic connector 6 to make it saturated with adsorption. Then, coat the coating liquid in step S8 on the exterior of both ends of the structure and dry the water to prepare the unsintered second sealing layer 7.

[0049] S10, placing the structure processed in step S9 in a kiln, heating it to 900-1300°C, and keeping it warm for 2-6 hours, thereby obtaining the ceramic membrane assembly 10. At this time, the second filter membrane layer and the second sealing layer 7 are also sintered.

[0050] Embodiment 2 like Figure 8 As shown, the difference between this embodiment and the first embodiment is that the ceramic membrane assembly 10 uses only 7 ceramic membrane tubes 1, and its connection structure and preparation method are similar to those of the first embodiment, which will not be described in detail.

[0051] like Fig. 9As shown, the present invention also discloses a ceramic membrane assembly, which includes a membrane shell 9, two flanges 11, two sealing rings 12 and the above-mentioned ceramic membrane assembly 10, and the ceramic membrane assembly 10 is placed in the inner cavity of the membrane shell 9. The flange 11 is detachably connected (bolted) to the end of the membrane shell 9, wherein a first inlet is provided on one flange 11, and a first outlet is provided on the other flange 11, and the shapes of the first inlet and the first outlet are adapted to the outer shape of the structure. The membrane shell 9 is provided with a second inlet and a second outlet, and the second inlet and the second outlet are both connected to the inner cavity of the membrane shell 9. The first inlet, the first flow channel and the first outlet are connected in sequence, and the sealing ring 12 seals the gap between the flange 11 and the ceramic membrane assembly 10, and the sealing ring 12 is provided with a through hole adapted to the outer shape of the structure.

[0052] like Figure 10-11 As shown, it is a comparison between the ceramic membrane tube 1 of the present invention and several commonly used ceramic membrane tubes 1. Fig. 9 It can be seen that the 40mm honeycomb structure ceramic membrane monomer (i.e., the ceramic membrane tube 1 of the present invention) uses an average of 50% less high-energy-consuming alumina material per square meter of filtration membrane area than the 40mm inner and outer circular and 30mm circular structure ceramic membrane monomers. Fig.10 It can be seen that the 40mm honeycomb structure ceramic membrane monomer (i.e., the ceramic membrane tube 1 of the present invention) has a significantly reduced cross-sectional area per square meter of filtration membrane area compared to the 40mm inner and outer circular and 30mm circular structure ceramic membrane monomers.

[0053] When filling and using, the conventional honeycomb structure composed of 19 ceramic membrane monomers, in which the ceramic membranes are independent of each other, also needs to be provided with honeycomb structure holes on its flange 11 and sealing ring 12 to correspond to each ceramic membrane tube 1, and these holes also make each ceramic membrane have a second flow channel 8. The structure of the membrane shell 9, flange 11 and sealing ring 12 are complex, and the processing is complex. During assembly, each ceramic membrane monomer needs to be installed one by one, which is troublesome. However, the integrated honeycomb structure of the present invention only needs to be provided with a hole with the same shape as the assembly on its corresponding flange 11 and sealing ring 12, which is simpler to process and convenient to install.

[0054] In addition, the integrated honeycomb structure of the present invention maximizes the high-density stacking of each ceramic membrane tube 1, and the inner diameter of the membrane shell 9 only requires 225 mm, while the honeycomb structure composed of 19 ceramic membrane units requires a corresponding membrane shell 9 of 265 mm. Compared with the present invention, the accumulated cavity inside the membrane shell 9 increases by 38%, which increases the cleaning fluid used for cleaning and the corresponding cleaning fluid discharge pollution.

[0055] In addition, the present invention uses the material of the transition layer membrane of the ceramic membrane tube 1 as the ceramic connector 6, and combines 19 ceramic membrane tubes 1 together. Since they are all made of α-alumina material, they are equally resistant to acid and alkali corrosion, and have the same temperature expansion coefficient. The overall structure is stable and durable, and can be used for 10-20 years in a 0-14 ph environment. Compared with using organic epoxy or polyurethane glue to bond a certain number of membranes into one, the glue and ceramic have different expansion coefficients and corrosion resistance. The corrosion resistance of organic glue is much worse than that of α-alumina, and it is generally required to be used in a 2-13 pH environment. After 1-3 years, the glue is easy to fall off, resulting in the separation and leakage of the overall combination.

[0056] Prepare the samples as follows: 100 parts of 45-micron α-phase alumina powder, 30 parts of 1.5-micron α-phase alumina powder, 6 parts of binder, 3 parts of lubricant and 25 parts of water were mixed together by mass, and then 20 127-hole hexagonal honeycomb structure ceramic membrane tubes 1 were extruded through a die, and then the temperature was slowly raised to 105 degrees Celsius for 48 hours to dry the moisture.

[0057] The dried ceramic membrane tube 1 green body is placed in a kiln, heated to 1750 degrees Celsius, kept warm for 6 hours, and sintered into a ceramic membrane tube 1.

[0058] 20 parts of 2.5 micron α-phase alumina powder, 2 parts of organic binder and 100 parts of water are stirred together at high speed according to mass proportions to form a coating liquid. The coating liquid is applied in the first flow channel 2 of the ceramic membrane tube 1 and the water is dried at 105 degrees Celsius.

[0059] 35 parts of 2.5-micron α-phase alumina powder, 5 parts of 0.3-micron α-phase alumina powder, 2 parts of organic binder and 100 parts of water are stirred together at high speed by mass to form a sealing liquid. The coating liquid is applied to the outside of both ends of the ceramic membrane tube 1 with a coating depth of 50 mm and a coating thickness of 100 microns. The water is dried at 105 degrees Celsius.

[0060] 100 parts of 2.5 micron α-phase alumina powder, 5 parts of a binder, and 15 parts of water are mixed together by weight and then molded, and extruded through a die to form a ceramic connector 6 green body with a width of 10 mm and a thickness of 3 mm; 19 127-hole hexagonal honeycomb structure tubular ceramic membranes are stacked into 5 layers, a hexagonal structure, and a hexagonal assembly of 19 ceramic membrane tubes 1. In the 5-layer structure, a plate-like green body is horizontally padded between every two layers to form a 3mm gap between each layer. A total of 5 ceramic connectors 6 green bodies are used as gaps along the length direction. Then, a pressure of 500N is applied to the hexagonal assembly in the horizontal direction for 300 seconds to make the ceramic membrane tube 1 and the ceramic connector 6 green bodies firmly bonded to each other. Then, the temperature is slowly raised to 105-130 degrees, kept warm for 10 hours, and the moisture is dried.

[0061] The assembled hexagonal assembly and the remaining single 127-hole hexagonal honeycomb structure tubular ceramic membrane are placed into the kiln, the temperature is raised to 1500 degrees Celsius, and the temperature is kept for 4 hours for sintering.

[0062] 20 parts of 0.4 micron α-phase alumina powder, 2 parts of organic binder and 100 parts of water are stirred together at high speed according to mass proportions to form a second coating liquid. The coating liquid is applied to the first flow channel 2 of the ceramic membrane tube 1, and then the temperature is slowly raised to 105 degrees, kept warm for 10 hours, and the moisture is dried.

[0063] The second coating liquid is slowly poured onto the ceramic cushion layer between the two layers of the dried assembly to make it saturated with adsorption, and the filter layer coating liquid is applied to the outer 50mm of both ends of the assembly. Then the moisture is dried at 105 degrees Celsius, and then the temperature is raised to 1300 degrees Celsius in a kiln and kept warm for 2 hours to sinter into an integral honeycomb ceramic membrane. The single 127-hole hexagonal honeycomb structure tubular ceramic membrane is sintered together as described above.

[0064] As a comparative example, the same formula and process as above were used to produce circular 40-37-4, 30-19-4, and 30-37-2.8 ceramic membranes for comparison. The test comparison results are shown in Table 1.

[0065] Table 1

[0066] 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 changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A ceramic membrane assembly, characterized in that: It includes a plurality of ceramic membrane tubes and a plurality of ceramic connecting parts; The cross section of the ceramic membrane tube is a regular hexagon; a plurality of first flow channels are arranged inside the ceramic membrane tube, and the first flow channels are arranged along the length direction of the ceramic membrane tube and penetrate the ceramic membrane tube; a filter membrane layer is provided on the inner wall of the first flow channel, or a filter membrane layer is provided on the outer wall of the ceramic membrane tube; The ceramic membrane tubes are divided into at least three membrane tube rows, and all the membrane tube rows are stacked to form a structure with a hexagonal cross-section; the ceramic membrane tubes of the same membrane tube row are arranged side by side, and the outer wall surfaces of two adjacent ceramic membrane tubes fit together; two adjacent membrane tube rows are connected and fixed by ceramic connectors, and the ceramic connectors fit together with the outer walls of the adjacent ceramic membrane tubes; there is a second flow channel between two adjacent membrane tube rows, and the second flow channel connects to the outside of the structure.

2. The ceramic membrane assembly according to claim 1, characterized in that: The cross-section of the first flow channel is a regular hexagon; the first flow channels are arranged in a honeycomb structure in the ceramic membrane tube, and the outer edge of the figure formed by the cross-sections of all the first flow channels is parallel to the outer wall of the ceramic membrane tube; the diameter of the inscribed circle of the ceramic membrane tube is equal to 40±2mm; 91 first flow channels are arranged inside the ceramic membrane tube, and the diameter of the inscribed circle of the first flow channel is 2.7-3.0mm; or, 127 first flow channels are arranged inside the ceramic membrane tube, and the diameter of the inscribed circle of the first flow channel is 2.2-2.5mm; the inner wall corners of the first flow channel are set as arc chamfers with a radius of 0.5mm.

3. The ceramic membrane assembly according to claim 1, characterized in that: A filter membrane layer is provided on the inner wall of the first flow channel; the filter membrane layer includes a first filter membrane layer and a second filter membrane layer, the first filter membrane layer is located between the second filter membrane layer and the inner wall of the first flow channel; the pore size of the first filter membrane layer is 500-2000nm, and the pore size of the second filter membrane layer is 20-200nm.

4. The ceramic membrane assembly according to claim 1 or 3, characterized in that: A first sealing layer is provided on the outer walls of both ends of the ceramic membrane tube, one end of the first sealing layer is flush with the end surface of the ceramic membrane tube, the first sealing layer has a width of 5-50mm, a thickness of 50-500μm, and a pore size of 0.5-5μm.

5. The ceramic membrane assembly according to claim 4, characterized in that: The filter membrane layer includes a first filter membrane layer and a second filter membrane layer, and the first filter membrane layer is located between the second filter membrane layer and the inner wall of the first flow channel; after the ceramic membrane tube is sintered and the first flow channel is coated with the first filter membrane layer and dried, the first sealing layer is coated and dried, and then the first filter membrane layer and the first sealing layer are sintered uniformly.

6. The ceramic membrane assembly according to claim 1 or 3, characterized in that: A second sealing layer is provided on the outside of both ends of the structure, and the pore size of the second sealing layer is 20-200nm; one end of the second sealing layer is flush with the end surface of the structure, and the width of the second sealing layer is 5-20mm and the thickness is 5-20μm.

7. The ceramic membrane assembly according to claim 6, characterized in that: The filter membrane layer includes a first filter membrane layer and a second filter membrane layer, and the first filter membrane layer is located between the second filter membrane layer and the inner wall of the first flow channel; after the first sealing layer is sintered, the second filter membrane layer is coated on the first flow channel and dried, and then the second sealing layer is coated and dried, and then the second filter membrane layer and the second sealing layer are sintered uniformly.

8. The ceramic membrane assembly according to claim 3, characterized in that: 10% of the main material of the second filter layer is added to the main material of the first filter layer to form the main material of the ceramic connector; at least three ceramic connectors are arranged between the two adjacent membrane tube arrays, and these ceramic connectors are arranged at equal intervals along the length direction of the ceramic membrane tube; the width of the ceramic connector is 3-10mm, and the thickness is 1-3mm; The ceramic connector is extruded. After the first filter membrane layer is coated and dried, the extruded ceramic connector is assembled with the ceramic membrane tube to form a structure. Then, a pressure of 100-1000N is applied to the periphery of the structure for 30-300min to make the ceramic membrane tube and the ceramic connector bonded to each other. Then, the temperature is raised to 105-130°C and kept warm for 4-10h to dry out the moisture. Then, the ceramic connector and the first filter membrane layer are sintered.

9. A ceramic membrane module, characterized in that: It comprises a membrane shell, two flanges, two sealing rings and a ceramic membrane assembly as described in any one of claims 1 to 8, wherein the ceramic membrane assembly is placed in the inner cavity of the membrane shell; the flange is detachably connected to the end of the membrane shell, and the sealing ring seals the gap between the flange and the ceramic membrane assembly; one of the flanges is provided with a first inlet, the other flange is provided with a first outlet, the membrane shell is provided with a second inlet and a second outlet, the first inlet, the first flow channel and the first outlet are connected in sequence, and the second inlet and the second outlet are both connected to the inner cavity of the membrane shell.

10. The ceramic membrane assembly according to claim 9, characterized in that: The shapes of the first inlet and the first outlet are matched with the outer shape of the structure, and the sealing ring is provided with a through hole matched with the outer shape of the structure.

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