阅读说明：本技术 一种中空平板陶瓷膜支撑体及制备方法 (Hollow flat ceramic membrane support and preparation method thereof ) 是由 尹晓琴 于 2021-07-30 设计创作，主要内容包括：本发明公开了一种中空平板陶瓷膜支撑体及其制备方法。所述制备方法包括如下步骤：(1)将骨料、造孔剂、粘结剂和水混匀造粒、干燥后,干压成型,得到表面具有凸起物的平板陶瓷膜支撑体坯体和表面平整的平板陶瓷膜支撑体坯体；所述凸起物均匀分布在平板陶瓷膜支撑体坯体的上表面,与支撑体长度方向一致或垂直,且在支撑体长度方向和宽度方向上呈现间隔并列排布；(2)将凸起物上涂覆浆料后与表面平整的平板陶瓷膜支撑体坯体进行拼接；(3)将拼接后的支撑体坯体经过干燥、排胶、烧结得到中空平板陶瓷膜支撑体。本发明所述制备方法简单高效,成本较低,良品率高。所述中空平板陶瓷膜支撑体具有孔隙率高、抗折强度高、过滤通量大的特点。(The invention discloses a hollow flat ceramic membrane support and a preparation method thereof. The preparation method comprises the following steps: (1) uniformly mixing aggregate, a pore-forming agent, a binder and water, granulating, drying, and performing dry pressing to obtain a flat ceramic membrane support body blank with protrusions on the surface and a flat ceramic membrane support body blank with a smooth surface; the projections are uniformly distributed on the upper surface of the flat ceramic membrane support body blank, are consistent with or vertical to the length direction of the support body, and are arranged in parallel at intervals in the length direction and the width direction of the support body; (2) coating slurry on the bulges, and splicing the bulges with a flat ceramic membrane support body blank with a smooth surface; (3) and drying, removing the glue and sintering the spliced support body blank to obtain the hollow flat ceramic membrane support body. The preparation method disclosed by the invention is simple and efficient, and has the advantages of lower cost and high yield. The hollow flat ceramic membrane support has the characteristics of high porosity, high breaking strength and large filtration flux.)

1. The preparation method of the hollow flat ceramic membrane support is characterized by comprising the following steps:

(1) uniformly mixing aggregate, a pore-forming agent, a binder and water, drying, crushing, sieving, granulating, drying, and performing dry pressing to obtain a flat ceramic membrane support body blank with protrusions on the surface and a flat ceramic membrane support body blank with a smooth surface; the projections are uniformly distributed on the upper surface of the flat ceramic membrane support body blank, are consistent with or vertical to the length direction of the support body, and are arranged in parallel at intervals in the length direction and the width direction of the support body;

(2) coating slurry on the projections on the surface of the flat ceramic membrane support body blank obtained in the step (1), and splicing the blank with the flat ceramic membrane support body blank;

(3) and (3) drying, removing the glue and sintering the spliced flat ceramic membrane support body blank obtained in the step (2) to obtain the hollow flat ceramic membrane support body.

2. The method for preparing a hollow flat ceramic membrane support according to claim 1, wherein the aggregate is a mixture of mineral raw materials and ceramic single-phase powder, and the ceramic single-phase powder is at least one of alumina, zirconia, titania and silicon carbide powder; the mineral raw material comprises the following components in percentage by mass: 5-95% of clay, 0-95% of mullite, 0-95% of bauxite, 0-10% of feldspar, 0-10% of dolomite, 0-33% of cordierite, 0-10% of calcite, 0-50% of micro silicon powder and 0-20% of bentonite; the mass percentage of the mineral raw material to the ceramic single-phase powder is 5-100%: 0 to 95 percent.

3. The method for preparing a hollow flat ceramic membrane support according to claim 1, wherein the pore-forming agent is one of starch, polymethyl methacrylate microspheres, sawdust, polysilane microspheres, cotton, bamboo powder, carbon black, graphite, and carbonate; the binder is at least one of polyvinyl alcohol, carboxymethyl cellulose, hydroxyethyl cellulose and lignocellulose.

4. The method for preparing a hollow flat ceramic membrane support according to claim 1, wherein the weight ratio of the aggregate, the pore-forming agent and the binder is as follows: pore-forming agent: binder 100: 5-20: 0.3-5.

5. A method for preparing a hollow flat ceramic membrane support according to claim 1, wherein in the step (1), the water content of the flat ceramic membrane support green body having the protrusions on the surface and the water content of the flat ceramic membrane support green body having a flat surface are 5% to 8%.

6. The method for preparing a hollow flat ceramic membrane support according to claim 1, wherein in the step (1), the pressure for dry pressing is 30 to 60 MPa.

7. The method for preparing a hollow flat ceramic membrane support according to claim 1, wherein in the step (3), the drying temperature is 30-150 ℃ and the drying time is 30-90 min; the temperature of the discharged glue is 600 ℃, the heat preservation time of the discharged glue is 10-120 min, and the heating rate of the discharged glue is 2-10 ℃/min; the sintering temperature is 1200-1500 ℃, and the sintering time is 30 min-3 h.

8. The method for preparing a hollow flat ceramic membrane support according to claim 1, wherein the protrusions are stripe-shaped protrusions, S-shaped protrusions, or dot-shaped protrusions.

9. The method for preparing a hollow flat ceramic membrane support according to claim 8, wherein the height of the protrusions is 0.05-1mm, and if the protrusions are stripe-shaped protrusions, the length of the protrusions is 5-1000mm, and the width of the protrusions is 0.5-30 mm; if the bulge is an S-shaped bulge, the length of the bulge is 5-1000mm, and the width of the bulge is 0.5-30 mm; if the bulge is a dot bulge, the diameter of the bulge is 2-100 mm; the interval size of the bulges in the length direction of the support body is 0.5-300mm, and the interval size in the width direction of the support body is 1-100 mm.

10. A hollow flat ceramic membrane support prepared by the method for preparing a hollow flat ceramic membrane support according to any one of claims 1 to 9.

Technical Field

The invention belongs to the technical field of ceramic membranes, and relates to a hollow flat ceramic membrane support and a preparation method thereof.

Background

The ceramic membrane support is generally composed of large-particle ceramic aggregate which has high strength, high temperature resistance, corrosion resistance and good thermal stability and a binder which is relatively easy to sinter, and the large-particle ceramic aggregate mainly provides high strength for the support. The support body forming technology includes extrusion molding, tape casting, gel casting and the like. However, the prior art has the following disadvantages: firstly, the most common technique for preparing the flat ceramic membrane is extrusion molding at present, because the moisture content of the molded blank is higher (more than 15%), the drying efficiency of the product is low, and particularly for large-size samples, the drying and sintering processes are very easy to deform and crack, so that the yield is very low. And the sample which is not deformed after being fired can also form a plurality of micro cracks, so that the product performance is reduced. Other preparation techniques include tape casting, gel casting and the like, and are only suitable for small tests of small-size products. Secondly, the ceramic membrane support body is expensive in raw material price and high in firing temperature, and aiming at the fields of separation processes which do not need strong acid resistance or strong alkali resistance, such as oil-water separation, seawater desalination, drinking water treatment and the like, the ceramic membrane support body prepared by adopting the raw materials of ceramic powder, pore-forming agent and binder is too high in price and high in energy consumption. Finally, the existing compression molding technology has the advantages that the addition amount of the pore-forming agent is small, pore channels are formed mainly by particle accumulation, the porosity is low, and the filtration flux is small; if the addition amount of the pore-forming agent is increased, phenomena such as black cores, warping, cracking and the like are easy to occur due to incomplete gel discharge; if the porosity is increased by reducing the sintering shrinkage by lowering the firing temperature or by reducing the pressing pressure to reduce the particle packing density, the strength of the support is seriously decreased.

Disclosure of Invention

In order to overcome the above disadvantages of the prior art, the present invention provides a hollow flat ceramic membrane support and a method for preparing the same.

In order to achieve the purpose, the invention adopts the technical scheme that:

a preparation method of a hollow flat ceramic membrane support comprises the following steps:

(1) uniformly mixing aggregate, a pore-forming agent, a binder and water, drying, crushing, sieving, granulating, drying, and performing dry pressing to obtain a flat ceramic membrane support body blank with protrusions on the surface and a flat ceramic membrane support body blank with a smooth surface; the projections are uniformly distributed on the upper surface of the flat ceramic membrane support body blank, are consistent with or vertical to the length direction of the support body, and are arranged in parallel at intervals in the length direction and the width direction of the support body;

(2) coating slurry on the projections on the surface of the flat ceramic membrane support body blank obtained in the step (1), and splicing with the flat ceramic membrane support body blank with a smooth surface;

(3) and (3) drying, removing the glue and sintering the spliced flat ceramic membrane support body blank obtained in the step (2) to obtain the hollow flat ceramic membrane support body.

According to the invention, a dry pressing forming technology is adopted, the moisture content of the obtained green body is 5% -8%, which is far lower than that of the green body of more than 15% in the prior art, and the phenomenon that the green body deforms and cracks in the drying and sintering processes to cause low yield can be avoided; the preparation method of the hollow flat ceramic membrane support has wide applicability to the dimension and specification of the support product, simple and efficient process method, lower cost and high yield. In addition, the projections on the surface of the flat ceramic membrane support body blank are arranged in parallel at intervals in the length direction and the width direction of the support body, so that the obtained hollow flat ceramic membrane support body has multiple channels, and the adjacent channels are communicated with each other, thereby being beneficial to improving the water flux.

As a preferred embodiment of the invention, the aggregate is a mixture of mineral raw materials and ceramic single-phase powder, and the mass percentage ratio of the mineral raw materials to the ceramic single-phase powder is 5% -95%: 5% -95%; the ceramic single-phase powder is at least one of alumina, zirconia, titanium dioxide and silicon carbide powder; the mineral raw material comprises the following components in percentage by mass: 5-95% of clay, 0-95% of mullite, 0-95% of bauxite, 0-10% of feldspar, 0-10% of dolomite, 0-33% of cordierite, 0-10% of calcite, 0-50% of micro silicon powder and 0-20% of bentonite; the mass percentage of the mineral raw material to the ceramic single-phase powder is 5-100%: 0 to 95 percent.

According to the invention, the mineral raw material is added to replace part of the ceramic single-phase powder, so that on one hand, the raw material cost can be reduced, and the cost of the support body is about 20% of the cost of the support body with the aggregate being only the ceramic single-phase powder; on the other hand, the thermal expansion can be reduced, and the phenomena of deformation and cracking caused by later drying and sintering are reduced. The mass percentage ratio of the mineral raw material to the ceramic single-phase powder in the aggregate affects the sintering temperature and time in the step (3), and when the aggregate only contains the ceramic single-phase powder, the sintering temperature and time are both increased, which reduces the cost and efficiency.

As a preferred embodiment of the invention, the pore-forming agent is one of starch, polymethyl methacrylate microspheres, polysilane microspheres, sawdust, cotton, bamboo powder, carbon black, graphite and carbonate; the binder is at least one of polyvinyl alcohol, carboxymethyl cellulose, hydroxyethyl cellulose and lignocellulose.

As a preferred embodiment of the invention, the weight ratio of the aggregate, the pore-forming agent and the binder is as follows: pore-forming agent: binder 100: 5-20: 0.3-5.

According to the invention, the porosity and the filtration flux of the support body are improved by increasing the addition amount of the pore-forming agent. The applicant of the invention proves through a large number of experiments that the hollow flat ceramic membrane support prepared from the aggregate, the pore-forming agent and the binder in the selection range of the types and the addition amount has the effects of high porosity, high breaking strength and large filtration flux.

As a preferred embodiment of the present invention, in the step (1), the moisture content of the flat ceramic membrane support body blank having the protrusions on the surface and the moisture content of the flat ceramic membrane support body blank having the flat surface are 5% to 8%.

The slurry is common slurry with a bonding effect, is not limited by a specific model, and can be a product sold in the market or made by the public.

More preferably, the slurry is a mixture of aggregate and water, and the weight ratio of the aggregate to the water is 50-70: 30-50.

In a preferred embodiment of the present invention, in the step (1), the pressure for dry pressing is 30 to 60 MPa.

In the step (3), the drying temperature is 30-150 ℃, and the drying time is 30-90 min; the temperature of the discharged glue is 600 ℃, the heat preservation time of the discharged glue is 10-120 min, and the heating rate of the discharged glue is 2-10 ℃/min; the sintering temperature is 1200-1500 ℃, and the sintering time is 30 min-3 h.

In the step (3), the temperature rise rate of sintering is 5-20 ℃/min.

As a preferred embodiment of the present invention, the protrusions are stripe-shaped protrusions, S-shaped protrusions, or dot-shaped protrusions.

The length of the flat ceramic membrane support body blank with the bulges on the surface and the flat ceramic membrane support body blank with the flat surface are 200-1200mm, the width is 50-600mm, and the height is 1-15 mm.

The size distribution of the flat ceramic membrane support body blank and the hollow flat ceramic membrane support body prepared by the preparation method of the hollow flat ceramic membrane support body is wider, so the preparation method has wide applicability to product size specifications.

As a preferred embodiment of the invention, the height of the protrusions is 0.05-1mm, if the protrusions are strip-shaped protrusions, the length of the protrusions is 5-1000mm, and the width of the protrusions is 0.5-30 mm; if the bulge is an S-shaped bulge, the length of the bulge is 5-1000mm, and the width of the bulge is 0.5-30 mm; if the bulge is a dot bulge, the diameter of the bulge is 2-100 mm; the interval size of the bulges in the length direction of the support body is 0.5-300mm, and the interval size in the width direction of the support body is 1-100 mm.

The hollow flat ceramic membrane support body has the length of 200-1200mm, the width of 50-600mm and the height of 2-30 mm.

The hole width of the hollow flat ceramic membrane support body is 1-100mm, and the height of the hollow flat ceramic membrane support body is 0.05-1 mm.

The invention also claims the hollow flat ceramic membrane support prepared by the preparation method of the hollow flat ceramic membrane support.

Compared with the prior art, the invention has the beneficial effects that:

(1) according to the invention, a dry pressing forming technology is adopted, the moisture content of the obtained green body is 5% -8%, which is far lower than that of the green body of more than 15% in the prior art, and the phenomenon that the green body deforms and cracks in the drying and sintering processes to cause low yield can be avoided; the preparation method of the hollow flat ceramic membrane support has wide applicability to the dimension and specification of the support product, simple and efficient process method, low cost and high yield.

(2) According to the invention, the mineral raw materials are added to replace part of the ceramic single-phase powder, so that the raw material cost can be greatly reduced, the thermal expansion can be reduced, and the phenomena of deformation and cracking caused by later drying and sintering can be reduced.

(3) The projections on the surface of the flat ceramic membrane support body blank are arranged in parallel at intervals in the length direction and the width direction of the support body, so that the obtained hollow flat ceramic membrane support body has a multi-hole channel in the internal structure, and the adjacent hole channels are communicated with each other, thereby being beneficial to improving the water flux.

(4) The hollow flat ceramic membrane support prepared by the preparation method has the effects of high porosity, high breaking strength and large filtration flux.

Drawings

Fig. 1 is a front view and a top view of a flat ceramic membrane support green body having protrusions on the surface thereof according to example 1 of the present invention;

FIG. 2 is a cross-sectional view and a longitudinal-sectional view of a hollow flat ceramic membrane support according to example 1 of the present invention;

FIG. 3 is a cross-sectional view and a longitudinal-sectional view of a hollow flat ceramic membrane support according to example 3 of the present invention;

FIG. 4 is a cross-sectional view and a longitudinal-sectional view of a hollow flat ceramic membrane support according to example 4 of the present invention;

FIG. 5 is a cross-sectional view and a longitudinal-sectional view of a hollow flat ceramic membrane support according to example 10 of the present invention.

Detailed Description

To better illustrate the objects, aspects and advantages of the present invention, the present invention will be further described with reference to specific examples.

In the embodiment and the comparative example of the invention, the slurry is a mixture of aggregate and water, and the aggregate comprises the following components in percentage by weight: 20 wt% of clay and 80 wt% of alumina, wherein the weight ratio of the aggregate to water is 75: 25.

example 1

The preparation method of the hollow flat ceramic membrane support in this embodiment includes the following steps:

(1) mixing 30 wt% of alumina, 20 wt% of zirconia, 20 wt% of kaolin, 20 wt% of mullite and 10 wt% of albite as aggregate of a support body, adding 5 wt% of sawdust, 10 wt% of starch and 30 wt% of carboxymethyl cellulose solution (with the concentration of 1 wt%) into the aggregate, drying, crushing, sieving and granulating, drying until the water content is 5-8%, and pressing under the pressure of 50MPa to prepare a flat ceramic membrane support body blank with the size of 1200 x 600 x 2mm and a flat surface, wherein the protrusions are uniformly distributed on the upper surface of the flat ceramic membrane support body blank, are consistent with the length direction of the support body, and are arranged at intervals in the length direction and the width direction of the support body; the length of the bulge is 30-200mm, the width is 3mm, and the thickness is 0.5 mm; the distance between the bulges is 50mm in the length direction of the support body and 100mm in the width direction;

(2) coating slurry on the projections on the surface of the flat ceramic membrane support body blank obtained in the step (1), and splicing with the flat ceramic membrane support body blank with a smooth surface;

(3) and (3) drying the spliced flat ceramic membrane support body blank obtained in the step (2) at 100 ℃ for 2 hours, heating to 600 ℃ at the speed of 10 ℃/min, discharging glue, preserving heat for 30min, heating to 1300 ℃ at the speed of 20 ℃/min, sintering and keeping for 1h to obtain the hollow flat ceramic membrane support body.

The obtained hollow flat ceramic membrane support has porosity of 36%, breaking strength of 40MPa, and pure water flux of 7600Lm^-2h^-1bar^-1。

Fig. 1 and 2 are a front view and a top view of a flat ceramic membrane support body green body and cross-sectional and longitudinal sectional views of a hollow flat ceramic membrane support body, respectively, as described in example 1. As can be seen from the figure, the strip-shaped protrusions are distributed on the surface of the flat ceramic membrane support body blank, the protrusions are distributed along the length direction of the support body, and are arranged in parallel at intervals in the length direction and the width direction of the support body, the longitudinal section of the support body comprises a plurality of rectangular holes, and according to the longitudinal section and the cross section, the support body comprises a plurality of channels which are mutually connected.

Example 2

The preparation method of the hollow flat ceramic membrane support in this embodiment includes the following steps:

(1) mixing 5 wt% of alumina and 95 wt% of kaolin serving as a support aggregate, adding 10 wt% of bamboo powder, 10 wt% of graphite and 16 wt% of lignocellulose solution (with the concentration of 5 wt%) serving as the aggregate into the aggregate, drying, crushing, sieving and granulating, drying until the water content is 5-8%, pressing under the pressure of 50MPa to prepare a flat ceramic membrane support body blank body with the size of 1200 x 600 x 2mm and a flat surface, wherein the protrusions are uniformly distributed on the upper surface of the flat ceramic membrane support body blank body, are consistent with the length direction of the support body, and are arranged at intervals in the length direction and the width direction of the support body; the length of the bulge is 30-200mm, the width is 5mm, and the thickness is 1 mm; the distance between the bulges is 30mm in the length direction of the support body and 15mm in the width direction;

(2) coating slurry on the projections on the surface of the flat ceramic membrane support body blank obtained in the step (1), and splicing with the flat ceramic membrane support body blank with a smooth surface;

(3) and (3) drying the spliced flat ceramic membrane support body blank obtained in the step (2) at 100 ℃ for 1.5 hours, heating to 600 ℃ at the speed of 10 ℃/min, discharging glue, keeping the temperature for 10min, heating to 1300 ℃ at the speed of 5 ℃/min, sintering and keeping for 1h to obtain the hollow flat ceramic membrane support body.

The obtained hollow flat ceramic membrane support has porosity of 40%, breaking strength of 34MPa, pure water flux of 6460Lm^-2h^-1bar^-1。

Example 3

The preparation method of the hollow flat ceramic membrane support in this embodiment includes the following steps:

(1) mixing 80 wt% of titanium dioxide, 15 wt% of bentonite and 5 wt% of silica fume as a support body aggregate, adding 5 wt% of carbon black and 16 wt% of lignocellulose solution (with the concentration of 5 wt%) into the aggregate, drying, crushing, sieving, granulating, drying until the water content is 5-8%, pressing under the pressure of 50MPa to prepare a flat ceramic membrane support body blank with the size of 1200 x 600 x 2mm and an S-shaped bulge on the surface and a flat ceramic membrane support body blank with the size of 1200 x 600 x 2mm and a flat surface, wherein the bulges are uniformly distributed on the upper surface of the flat ceramic membrane support body blank, are consistent with the length direction of the support body, and are arranged at intervals in the length direction and the width direction of the support body; the length of the bulge is 30-200mm, the width is 5mm, and the thickness is 0.5 mm; the distance between the bulges is 30mm in the length direction of the support body and 15mm in the width direction;

(2) coating slurry on the projections on the surface of the flat ceramic membrane support body blank obtained in the step (1), and splicing with the flat ceramic membrane support body blank with a smooth surface;

(3) and (3) drying the spliced flat ceramic membrane support body blank obtained in the step (2) at 100 ℃ for 1 hour, heating to 600 ℃ at the speed of 10 ℃/min, carrying out gel removal and heat preservation for 120min, heating to 1400 ℃ at the speed of 5 ℃/min, and sintering for 2h to obtain the hollow flat ceramic membrane support body.

The obtained hollow flat ceramic membrane support has the porosity of 22 percent, the breaking strength of 35MPa and the pure water flux of 3520Lm^-2h^-1bar^-1。

FIG. 3 is a cross-sectional view and a longitudinal-sectional view of the hollow flat ceramic membrane support described in example 3, respectively. As can be seen from the figure, the S-shaped protrusions are distributed on the surface of the flat ceramic membrane support body blank, the protrusions are distributed along the length direction of the support body and are arranged in parallel at intervals in the length direction and the width direction of the support body, the longitudinal section of the support body comprises a plurality of rectangular holes, and according to the longitudinal section and the cross section, the support body comprises a plurality of channels which are mutually connected.

Example 4

The preparation method of the hollow flat ceramic membrane support in this embodiment includes the following steps:

(1) taking 10 wt% of silicon carbide powder, 10 wt% of dolomite, 10 wt% of calcite, 33 wt% of cordierite and 37 wt% of bauxite as aggregate of a support body, adding 10 wt% of graphite and 30 wt% of hydroxyethyl cellulose solution (with the concentration of 1 wt%) into the aggregate, mixing, drying, crushing, sieving and granulating, drying until the water content is 5-8%, pressing under the pressure of 60MPa to prepare a flat ceramic membrane support body blank body with the size of 1200 x 600 x 2mm and circular-point bulges on the surface and a flat ceramic membrane support body blank body with the size of 1200 x 600 x 2mm and smooth surface, wherein the bulges are uniformly distributed on the upper surface of the flat ceramic membrane support body blank body, are consistent with the length direction of the support body, and are arranged at intervals in the length direction and the width direction of the support body; the diameter of the bulges is 2mm, the bulges are spaced at intervals of 30mm in the length direction of the support body and at intervals of 15mm in the width direction;

(2) coating slurry on the bulges on the surface of the flat ceramic membrane support body blank obtained in the step (1), and splicing the bulges with the flat ceramic membrane support body blank;

(3) and (3) drying the spliced blank body of the flat ceramic membrane support body obtained in the step (2) at 100 ℃ for 1 hour, heating to 600 ℃ at the speed of 10 ℃/min, discharging glue, preserving heat for 30min, heating to 1300 ℃ at the speed of 5 ℃/min, sintering and keeping for 1h to obtain the hollow flat ceramic membrane support body.

ObtainedThe porosity of the hollow flat ceramic membrane support body is 25 percent, the breaking strength is 43MPa, and the pure water flux is 4000Lm^-2h^-1bar^-1。

FIG. 4 is a cross-sectional view and a longitudinal-sectional view of the hollow flat ceramic membrane support described in example 4, respectively. As can be seen from the figure, the surface of the flat ceramic membrane support body blank is distributed with round dot bulges, the bulges are distributed along the length direction of the support body and are arranged in parallel at intervals in the length direction and the width direction of the support body, the longitudinal section of the support body comprises a plurality of rectangular holes, and according to the longitudinal section and the cross section, the support body is seen to comprise a plurality of interconnected channels.

Example 5

The preparation method of the hollow flat ceramic membrane support in this embodiment is different from that in embodiment 2 only in that: in the step (1), the adding amount of the alumina in the aggregate of the support body is 45 wt%, and the adding amount of the kaolin is 55 wt%; and (3) heating to 1360 ℃ at the speed of 5 ℃/min, and sintering for 1h to obtain the hollow flat ceramic membrane support.

The obtained hollow flat ceramic membrane support has porosity of 42%, breaking strength of 35MPa, and pure water flux of 7560Lm^-2h^-1bar^-1。

Example 6

The preparation method of the hollow flat ceramic membrane support in this embodiment is different from that in embodiment 2 only in that: in the step (1), the adding amount of the alumina in the aggregate of the support body is 95 wt%, and the adding amount of the kaolin is 5 wt%; and (3) heating to 1460 ℃ at the speed of 5 ℃/min, and sintering for 2 hours to obtain the hollow flat ceramic membrane support.

The obtained hollow flat ceramic membrane support has porosity of 42%, breaking strength of 33MPa, and pure water flux of 7600Lm^-2h^-1bar^-1。

Example 7

The preparation method of the hollow flat ceramic membrane support in this embodiment is different from that in embodiment 3 only in that: in the step (1), carbon black with the aggregate amount of 20 wt% is added into the aggregate.

Obtained byThe hollow flat ceramic membrane support has the porosity of 37 percent, the breaking strength of 42MPa and the pure water flux of 5890Lm^-2h^-1bar^-1。

Example 8

The preparation method of the hollow flat ceramic membrane support in this embodiment is different from that in embodiment 3 only in that: in the step (1), carbon black accounting for 12 wt% of the aggregate is added into the aggregate.

The obtained hollow flat ceramic membrane support has porosity of 33%, breaking strength of 50MPa, and pure water flux of 4940Lm^-2h^-1bar^-1。

Example 9

The preparation method of the hollow flat ceramic membrane support in this embodiment is different from that in embodiment 3 only in that: in the step (1), carbon black with the aggregate amount of 8 wt% is added into the aggregate.

The obtained hollow flat ceramic membrane support has a porosity of 28%, a breaking strength of 56MPa, and a pure water flux of 4090Lm^-2h^-1bar^-1。

Example 10

The preparation method of the hollow flat ceramic membrane support in this embodiment is different from that in embodiment 4 only in that: in the step (1), the diameter of the dot bulge is 100 mm; the protrusions were spaced apart by 100mm in the longitudinal direction of the support and by 50mm in the width direction.

The obtained hollow flat ceramic membrane support has porosity of 25%, breaking strength of 43MPa, and pure water flux of 3980Lm^-2h^-1bar^-1。

FIG. 5 is a cross-sectional view and a longitudinal-sectional view of the hollow flat ceramic membrane support according to example 10. As can be seen from the figure, the surface of the flat ceramic membrane support body blank is distributed with round dot bulges, the bulges are distributed along the length direction of the support body and are arranged in parallel at intervals in the length direction and the width direction of the support body, the longitudinal section of the support body comprises a plurality of rectangular holes, and according to the longitudinal section and the cross section, the support body is seen to comprise a plurality of interconnected channels.

Example 11

The preparation method of the hollow flat ceramic membrane support in this embodiment includes the following steps:

(1) mixing, drying, crushing, sieving and granulating 10 wt% of potassium feldspar, 20 wt% of dolomite, 30 wt% of kaolin, 30 wt% of mullite and 10 wt% of albite serving as aggregate, adding 10 wt% of bamboo powder, 10 wt% of graphite and 16 wt% of lignocellulose solution (with the concentration of 5 wt%) into the aggregate, drying until the water content is 5-8%, pressing under the pressure of 50MPa to prepare a flat ceramic membrane support body blank body with strip-shaped protrusions on the surface and the size of 1200-600-2 mm and a flat ceramic membrane support body blank body with a flat surface, wherein the protrusions are uniformly distributed on the upper surface of the flat ceramic membrane support body blank body, are consistent with the length direction of the support body, and are arranged at intervals in the length direction and the width direction of the support body; the length of the bulge is 30-200mm, the width is 5mm, and the thickness is 1 mm; the distance between the bulges is 30mm in the length direction of the support body and 15mm in the width direction;

(2) coating slurry on the projections on the surface of the flat ceramic membrane support body blank obtained in the step (1), and splicing with the flat ceramic membrane support body blank with a smooth surface;

(3) and (3) drying the spliced flat ceramic membrane support body blank obtained in the step (2) at 100 ℃ for 1.5 hours, heating to 600 ℃ at the speed of 10 ℃/min, discharging glue, keeping the temperature for 10min, heating to 1200 ℃ at the speed of 10 ℃/min, and sintering for 10min to obtain the hollow flat ceramic membrane support body.

The obtained hollow flat ceramic membrane support has porosity of 32%, breaking strength of 30MPa, pure water flux of 6900Lm^-2h^-1bar^-1。

Comparative example 1

The preparation method of the hollow flat ceramic membrane support in the comparative example comprises the following steps:

(1) adding 10 wt% of bamboo powder, 10 wt% of graphite and 16 wt% of lignocellulose solution (with the concentration of 5 wt%) into the aggregate, mixing, drying, crushing, sieving and granulating, then drying until the water content is 5-8%, pressing under the pressure of 50MPa to prepare a flat ceramic membrane support body blank body with the size of 1200 x 600 x 2mm and a flat ceramic membrane support body blank body with the size of 1200 x 600 x 2mm, wherein the protrusions are uniformly distributed on the upper surface of the flat ceramic membrane support body blank body, are consistent with the length direction of the support body, and are arranged in parallel at intervals in the length direction and the width direction of the support body; the length of the bulge is 30-200mm, the width is 5mm, and the thickness is 1 mm; the distance between the bulges is 30mm in the length direction of the support body and 15mm in the width direction;

(2) coating slurry on the projections on the surface of the flat ceramic membrane support body blank obtained in the step (1), and splicing with the flat ceramic membrane support body blank with a smooth surface;

(3) and (3) drying the spliced flat ceramic membrane support body blank obtained in the step (2) at 100 ℃ for 1.5 hours, heating to 600 ℃ at the speed of 10 ℃/min, discharging glue, keeping the temperature for 10min, heating to 1600 ℃ at the speed of 5 ℃/min, and sintering for 3h to obtain the hollow flat ceramic membrane support body.

The obtained hollow flat ceramic membrane support has porosity of 38%, breaking strength of 30MPa, and pure water flux of 6000Lm^-2h^-1bar^-1。

Comparative example 2

The preparation method of the hollow flat ceramic membrane support in the comparative example comprises the following steps:

(1) mixing 80 wt% of titanium dioxide, 15 wt% of bentonite and 5 wt% of silica fume as a support body aggregate, adding 25 wt% of carbon black and 16 wt% of lignocellulose solution (with the concentration of 5 wt%) into the aggregate, drying, crushing, sieving, granulating, drying until the water content is 5-8%, pressing under the pressure of 50MPa to prepare a flat ceramic membrane support body blank with the size of 1200 x 600 x 2mm and an S-shaped bulge on the surface and a flat ceramic membrane support body blank with the size of 1200 x 600 x 2mm and a flat surface, wherein the bulges are uniformly distributed on the upper surface of the flat ceramic membrane support body blank, are consistent with the length direction of the support body, and are arranged at intervals in the length direction and the width direction of the support body; the length of the bulge is 30-200mm, the width is 5mm, and the thickness is 0.5 mm; the distance between the bulges is 30mm in the length direction of the support body and 15mm in the width direction;

(2) coating slurry on the projections on the surface of the flat ceramic membrane support body blank obtained in the step (1), and splicing with the flat ceramic membrane support body blank with a smooth surface;

(3) and (3) drying the spliced flat ceramic membrane support body blank obtained in the step (2) at 100 ℃ for 1 hour, heating to 600 ℃ at the speed of 10 ℃/min, carrying out gel removal and heat preservation for 120min, heating to 1400 ℃ at the speed of 5 ℃/min, and sintering for 2h to obtain the hollow flat ceramic membrane support body.

The obtained hollow flat ceramic membrane support has a porosity of 45%, a breaking strength of 15MPa and a pure water flux of 4800Lm^-2h^-1bar^-1。

Comparative example 3

The preparation method of the hollow flat ceramic membrane support in the proportion is only different from that of the hollow flat ceramic membrane support in the embodiment 3: in the step (1), the amount of carbon black is 1 wt% of the aggregate.

The obtained hollow flat ceramic membrane support has a porosity of 13%, a breaking strength of 42MPa and a pure water flux of 2200Lm^-2h^-1bar^-1。

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the protection scope of the present invention, and although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.