Granules based on ceramic powder preparation, and preparation method and application thereof

Abstract

This invention relates to a granulated body prepared from ceramic powder, its preparation method, and its application. The preparation method includes using ceramic powder as raw material and using smooth micro-granules with a particle size of 400 mesh or larger and 100 mesh or smaller as a barrier. The composition of the barrier is the same as that of the ceramic powder used as raw material. The ceramic powder and the barrier are mixed and granulated using a rolling granulation method. After granulation, the granules are sieved to obtain granules with a particle size of 40-100 mesh. This method does not require the addition of any binder. By adding the barrier, the yield of 40-100 mesh granules after a single granulation of ceramic powder is significantly improved, and the yield increases with the increase of the amount of barrier added, which can significantly improve the effective utilization rate of ceramic powder. The green body obtained by pressing the 40-100 mesh granules obtained by this method has a uniform mass distribution and can be used to prepare optical glass.

Description

Technical Field

[0001] This invention relates to the field of granulation technology, and more specifically to a granulated body prepared from ceramic powder, its preparation method, and its application. Background Technology

[0002] Miniaturization of optical devices is a trend in their development, which places higher demands on the precision of the miniaturized fabrication process for optical glass. For some specialized optical glass materials, such as indium tin oxide (In₂O₃-SnO₂), the powder is finely milled to the nanometer scale (1-100nm), with mold sizes as small as 0.4-1.3mm, requiring high manufacturing precision within ±10% of the tolerance. However, the finer the powder, the lighter the particles and the worse the flowability. Simultaneously, the larger the specific surface area and volume of the powder, the more difficult it is to uniformly fill the mold during dry pressing, easily leading to voids. This results in low density and uneven volume and mass distribution in the sintered green body. To address this, a method of granulating the raw powder before use has been proposed.

[0003] Existing granulation methods include wet granulation and dry granulation. Wet granulation, as described in patent CN102482140A (Method for Manufacturing Granulated Matter and Method for Manufacturing Glass Products), involves preparing a raw material slurry from boric acid-containing glass raw materials and a boric acid-soluble liquid, followed by spray drying to obtain granules with an average particle size of 30–1000 μm. Patent CN107074603A (Method for Manufacturing Granulated Glass Raw Materials, Method for Manufacturing Molten Glass, and Method for Manufacturing Glass Articles) describes granulating a glass raw material composition in the presence of water, resulting in granules with an average particle size D50 of 412 μm–2 mm. It is evident that wet granulation generally yields granules with a wide particle size distribution, and the morphology of spray-granulated particles is difficult to control, easily leading to defects such as hollow particles and surface pits, which can reduce the flowability and sintering performance of the granules.

[0004] Dry granulation, as described in patent CN111620547A, involves mixing various glass raw materials with 1-10% neutral silica sol binder and feeding the mixture into an extrusion molding machine to obtain spherical or flake-shaped granules with a diameter of 0.5-3 mm. The resulting granules have a relatively large particle size, and a binder needs to be added during granulation. CN104114502A describes a granule and its manufacturing method, in which granules are obtained by rolling granulation without pulverizing the glass raw material mixture. The median particle size D50 is 350-5000 μm. Typically, necessary granulation components such as binders and dispersants need to be added. The binder needs to be removed later through debinding. If the removal is incomplete, it will affect the sintering performance of the green body. Therefore, the debinding requirements are high, and the debinding process needs to be precisely controlled.

[0005] However, granules vary depending on the glass application. For example, glass substrates for various displays require alkali-free glass granules that are substantially free of alkali metal oxides. Meanwhile, the preparation of high-refractive-index glass using niobium oxide and lanthanum oxide (Nb₂O₅-La₂O₃) systems and dry pressing processes require raw material powders with specific particle sizes. If the powder particles are large, the porosity is large, making the mass distribution uncontrollable after filling the mold. If the powder particles are too fine, their flowability is poor, and voids easily appear in the mold, resulting in low compactness and uneven volume and mass distribution of the preform. Although existing granules, after screening, can meet the particle size requirements of dry pressing processes (e.g., 40–100 mesh), the proportion of granules meeting these requirements is low, leading to low effective utilization of raw material powders. Furthermore, granulation usually requires the addition of binders and other organic substances, the type of which significantly affects the particle size and dispersibility of the granules. Therefore, researching a granulation method that requires no binders and has high raw material powder utilization is of great significance. Summary of the Invention

[0006] To address the aforementioned deficiencies or improvement needs of existing technologies, this invention provides a granulated body based on ceramic powder, its preparation method, and its application. The aim is to discover that using smooth-surfaced microgranules with a particle size of 400 mesh or larger but less than 100 mesh as a barrier, added to ceramic powder for rolling granulation, can significantly increase the mass proportion of granules with a specific particle size (40-100 mesh) in a single granulation of ceramic powder, thereby improving the effective utilization rate of the ceramic powder. Furthermore, no binder needs to be added during the preparation process. This solves the technical problem of existing dry granulation methods resulting in a wide particle size distribution after a single granulation, requiring sieving to obtain granules that meet specific pressing requirements, and resulting in a low yield of 40-100 mesh granules, leading to a low effective utilization rate of the raw material powder.

[0007] To achieve the above objectives, according to one aspect of the present invention, a method for preparing granules based on ceramic powder is provided, comprising the following steps:

[0008] Using ceramic powder as raw material, and using smooth micro-granules with a particle size of 400 mesh or more and 100 mesh or less as a barrier; the composition of the barrier is the same as that of the ceramic powder used as raw material.

[0009] After the ceramic powder and the barrier are mixed evenly, they are granulated by rolling granulation. After granulation, the granules are sieved to obtain granules with a particle size of 40 mesh or larger, 40-100 mesh, and smaller than 100 mesh. Among them, the granules with a particle size of 40-100 mesh are qualified granules.

[0010] Preferably, in the method for preparing granules based on ceramic powder, the ceramic powder has a particle size of 20-80 μm.

[0011] Preferably, the method for preparing granules based on ceramic powder involves mixing the ceramic powder and the barrier material at a mass ratio of 1:(0.2-1).

[0012] Preferably, in the method for preparing granules based on ceramic powder, the barrier is a smooth-surfaced microgranule obtained by rolling granulation and sieving of the ceramic powder used as raw material, with a particle size of 400 mesh or more and 100 mesh or less.

[0013] Preferably, the method for preparing granules based on ceramic powder involves dividing the ceramic powder into n batches, and using the smooth-surfaced micro-granules with a particle size of 400 mesh or more and less than 100 mesh after granulation of the first to i-1 batches of ceramic powder as the barrier for granulation of the i-th batch of ceramic powder, where i is 2, 3, ... n.

[0014] Preferably, the method for preparing granules based on ceramic powder further includes re-granulating the granules with a particle size of 40 mesh or more and / or granules with a particle size of 100 mesh or less after sieving.

[0015] Preferably, in the method for preparing granules based on ceramic powder, the ceramic powder is barium zirconate titanate ceramic powder, which includes BaCO3, ZrO2, and TiO2, and has a purity of 99.9% or higher.

[0016] Preferably, in the method for preparing granules based on ceramic powder, the rolling granulation is carried out using a disc granulator, wherein the disc rotation speed is 20-40 r / min and the granulation time is 3-10 min.

[0017] According to another aspect of the present invention, a granulated body based on ceramic powder is also provided, which is prepared according to the method described in the present invention.

[0018] According to another aspect of the invention, the application of the granules prepared by the method described herein in the preparation of optical glass is also provided.

[0019] In summary, compared with the prior art, the above-described technical solutions conceived by this invention, by adding smooth-surfaced microparticles of 400 mesh or less and 100 mesh or less as a barrier to the ceramic powder, and the composition of the barrier being the same as that of the ceramic powder used as raw material, can achieve the following:

[0020] Beneficial effects:

[0021] The granulation preparation method provided by this invention uses ceramic powder as raw material and smooth microgranules with a surface size of less than 400 mesh and less than 100 mesh as a barrier. The composition of the barrier is the same as that of the ceramic powder used as raw material. No binder needs to be added. Granulation is carried out by rolling granulation method. Not only can granules that meet the requirements be obtained, but the yield of 40-100 mesh granules is significantly higher than the yield of direct granulation of existing powders. Moreover, the yield of 40-100 mesh granules increases with the increase of the amount of barrier added, which can significantly improve the effective utilization rate of raw material powder. The effective utilization rate of raw material powder in a single granulation can reach more than 80%. Attached Figure Description

[0022] Figure 1 This refers to the ceramic powder obtained after ceramic pulverization in Example 1;

[0023] Figure 2 It is the 40-100 mesh granulated body obtained by disc granulation of ceramic powder in Example 1. Detailed Implementation

[0024] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0025] In experiments, this invention discovered that using ceramic powder as raw material and smooth microgranules with a particle size of 400 mesh or more but less than 100 mesh as a barrier, wherein the composition of the barrier is the same as that of the ceramic powder used as raw material, and without adding a binder, granulation using a rolling granulation method can not only obtain granules with specific particle size requirements (40-100 mesh), but also significantly increase the mass proportion of granules with a particle size of 40-100 mesh after a single granulation. Furthermore, as the amount of barrier added increases, the proportion of granules with a particle size of 40-100 mesh after a single granulation shows a significant increase. Preferably, the ceramic powder and the barrier are mixed at a mass ratio of 1:(0.2-1), and the barrier can be reused after granulation.

[0026] This invention provides a method for preparing granules based on ceramic powder, comprising the following steps:

[0027] Using ceramic powder as raw material, micro-granules with a particle size of 400 mesh or more and a smooth surface of less than 100 mesh are used as a barrier. The composition of the barrier is the same as that of the ceramic powder used as raw material, so as to avoid the barrier and ceramic powder from affecting the performance of ceramic powder after granulation, such as sintering performance, due to different compositions.

[0028] After the ceramic powder and the barrier are mixed evenly according to a preset ratio, they are granulated by rolling granulation. After granulation, they are sieved through 40 mesh and 100 mesh sieves to obtain granules with a mesh size of 40 or larger, granules with a mesh size of 40 to 100 mesh, and granules with a mesh size of less than 100 mesh. Among them, the granules with a mesh size of 40 to 100 mesh have good fluidity during the later dry pressing and molding process, which can meet the requirements of ceramic green body pressing. In this invention, the granules with a mesh size of 40 to 100 mesh are used as qualified granules.

[0029] The ceramic powder is preferably ceramic powder with a mesh size of less than 100. According to the correspondence between mesh size and particle size, 100 mesh corresponds to a particle size of approximately 150 μm.

[0030] In some embodiments, ceramic powder obtained by crushing dried ceramics is used as raw material, preferably ceramic powder with a particle size of 20-80 μm.

[0031] More preferably, the preset ratio is used to mix the ceramic powder and the barrier body at a mass ratio of 1:(0.2~1), and granulation is carried out by rolling method.

[0032] In some embodiments, the barrier is a smooth-surfaced micro-granulation of the ceramic powder used as raw material, which is sieved through a rolling granulation process with a mesh size of 400 or larger and a mesh size of 100 or smaller. The raw material granulated in this way does not use any additives and has high purity.

[0033] The method preferably divides the ceramic powder into n batches (n≥2 and is an integer), and uses the smooth-surfaced micro-granules with a particle size of 400 mesh or more and less than 100 mesh after granulation of the ceramic powder from the first batch to the (i-1)th batch as the barrier for granulation of the ceramic powder in the i-th batch, where i is 2, 3, ... n.

[0034] In some embodiments, the ceramic powder is barium zirconate titanate ceramic powder with a particle size of 20-80 μm and a purity of 99.9% or higher.

[0035] The rolling granulation method uses a disc granulator, wherein the disc rotation speed is set to 20-40 r / min and the granulation time is 3-10 min.

[0036] Furthermore, the method further includes re-grinding the granulated particles with a particle size of 40 mesh or larger and / or granulated particles with a particle size of 100 mesh or smaller after sieving to obtain ceramic powder, and then repeating the granulation process according to the above method.

[0037] In some embodiments, the dried ceramic is pulverized into ceramic powder using a crusher and divided into n portions (n ​​is an integer and n≥2). The specific preparation method is as follows:

[0038] First granulation: Take the first part of ceramic powder and add it to the disc granulator. The disc rotation speed is 20-40 r / min during granulation, and the granulation time is 3-10 min. After the first granulation, the powder is sieved into 40-100 mesh granules, 40 mesh and above 40 mesh granules and below 100 mesh granules. Among them, the granules with a particle size of 40-100 mesh are qualified granules.

[0039] Second granulation: Take the second portion of ceramic powder and add the granules obtained from the first granulation and sieving, which are between 400 mesh and 100 mesh, as a barrier. Mix the ceramic powder and the barrier at a mass ratio of 1:(0.2~1). The disc rotation speed is 20-40 r / min during granulation, and the granulation time is 3-10 min. After the second granulation, sieve the powder into 40-100 mesh, 40 mesh and above, and 100 mesh and below.

[0040] Following the steps of the second granulation, granulation and sieving are completed sequentially.

[0041] That is, the i-th granulation: take the i-th part of ceramic powder, add the granules obtained from the first to (i-1)th granulation and sieving that are above 400 mesh and below 100 mesh as a barrier, and mix them according to the mass ratio of ceramic powder to barrier 1:(0.2~1). The rotation speed of the disc during granulation is set to 20~40 r / min, and the granulation time is 3~10 min. After the i-th granulation is completed, the sieving is divided into granules of 40~100 mesh, granules above 40 mesh, and granules below 100 mesh, where i is 2, 3, ... n.

[0042] Furthermore, all the granules larger than 40 mesh and smaller than 100 mesh obtained from the above n granulation and sieving processes are crushed again into ceramic powder, and the above preparation method is repeated for granulation, as follows:

[0043] The (n+1)th granulation: Granules of 40 mesh or higher and 100 mesh or lower obtained from the first to the nth granulation and sieving are crushed into powder by a crusher with the disc speed set to 20-40 r / min and granulation time 3-10 min. After the (n+1)th granulation, the granules are sieved into 40-100 mesh granules, 40 mesh or higher granules, and 100 mesh or lower granules.

[0044] The (n+2)th granulation: Take the granules above 40 mesh after the (n+1)th granulation and sieve, crush them into powder, add the granules above 400 mesh and below 100 mesh after the (n+1)th granulation and sieve as a barrier, mix them according to the mass ratio of powder to barrier 1:(0.2~1) to complete the granulation, and sieve them into granules of 40~100 mesh, granules above 40 mesh, and granules below 100 mesh;

[0045] The (n+3)th granulation: Take the granules above 40 mesh after the (n+2)th granulation and sieve, crush them into powder, and add the granules above 400 mesh and below 100 mesh after the (n+1)th and (n+2)th granulation and sieve as a barrier. Mix them according to the mass ratio of powder to barrier at 1:(0.2~1) to complete the granulation, and sieve them into granules of 40-100 mesh, granules above 40 mesh, and granules below 100 mesh.

[0046] In this invention, the above steps can be followed and so on, until the total yield of 40-100 mesh granules is greater than or equal to a preset threshold, or meets the actual requirements.

[0047] In some embodiments, the ceramic powder is barium zirconate titanate (BZT) ceramic powder with the chemical formula BaZr. x Ti 1- x O3, x = 0.1, whose main components include BaCO3, ZrO2 and TiO2, all with a purity of over 99.9%; the ceramic powder was divided into 4 parts and granulated 7 times according to the above preparation method. The final yield of granules was 92.7%, which is significantly higher than the utilization rate of existing raw material powder (generally less than 50%). After adding a barrier and performing a single granulation, the yield of 40-100 mesh granules was higher than 60%, which is significantly improved compared to the yield of 40-100 mesh granules after direct granulation of ceramic powder (less than 50%).

[0048] In addition, the present invention also provides a granulated body based on ceramic powder, which is prepared according to the preparation method described in the present invention.

[0049] The granules have a particle size of 40-100 mesh and are composed of ceramic powder; the ceramic powder includes barium zirconate titanate ceramic powder, wherein BaCO3, ZrO2, and TiO2 have a purity of 99.9% or higher.

[0050] In addition, the present invention also provides an application of the granules prepared by the preparation method described in the present invention in the preparation of optical glass.

[0051] The following are examples.

[0052] Example 1

[0053] This embodiment uses barium zirconate titanate (BZT) ceramic as raw material, with the chemical formula BaZr. x Ti 1-x O3, x = 0.1, includes BaCO3, ZrO2, and TiO2, all with a purity of 99.9%.

[0054] The total mass of barium zirconate titanate (BZT) ceramic was 400g. After ball milling and drying, it was crushed by a crusher to obtain ceramic powder as follows: Figure 1As shown, its particle size is 20-80 μm.

[0055] Take 200g of the above ceramic powder and add 65g of a barrier with a particle size of 400 mesh or more and 100 mesh or less. The composition of the barrier is the same as that of the ceramic powder used as raw material, that is, the composition of the barrier is the same as that of the raw material BZT, which includes BaCO3, ZrO2 and TiO2, all with a purity of 99.9%.

[0056] Granulation was performed using a disc granulator. The disc rotation speed was set to 20 r / min to avoid forming large granules. Granulation lasted 3 minutes. After granulation, the granules were passed through 40-mesh and 100-mesh sieves to obtain the desired 40-100 mesh granules. Figure 2 As shown, the granules have a smooth surface, and the yield of 40-100 mesh granules is 65%, meaning that the effective utilization rate of ceramic powder after a single granulation is 65%.

[0057] The granules obtained above, after being pressed and molded, showed a high degree of sheet quality, indicating that the granules have good flowability and uniform filling of the mold.

[0058] Comparative Example 1

[0059] Take 200g of ceramic powder from Example 1 and add it to a disc granulator. The disc rotation speed is the same as in Example 1. Granulation takes 3 minutes. After granulation, the powder is sieved to obtain 40-100 mesh granules. The yield of 40-100 mesh granules is 37%, which means that the effective utilization rate of ceramic powder after a single granulation is 37%.

[0060] Example 2

[0061] This embodiment uses barium zirconate titanate (BZT) ceramic as raw material, with the chemical formula BaZr. x Ti 1-x O3, x = 0.1, includes BaCO3, ZrO2, and TiO2, all with a purity of 99.99%.

[0062] The total mass of barium zirconate titanate (BZT) ceramic was 754g. After ball milling and drying, it was crushed using a crusher, specifically as in Example 1. The obtained ceramic powder was divided into four portions: 200g, 200g, 200g, and 154g. The granulation steps for the ceramic powder are as follows:

[0063] First granulation: Take the first batch of 200g of powder and add it to the disc granulator. Set the disc speed to 40r / min during granulation to avoid forming large spheres. Granulate for 3 minutes. After granulation, sieve the granules into qualified and unqualified granules. Qualified granules are 40-100 mesh granules, and unqualified granules are granules above 40 mesh and granules below 100 mesh. The first batch of 200g of powder yielded 75g of 40-100 mesh granules, 60g of 40 mesh and above, and 65g of below 100 mesh. That is, the yield of 40-100 mesh granules after a single granulation is 37.5%, which means the effective utilization rate of ceramic powder is 37.5%.

[0064] Second granulation: Testing revealed that the particle size of granules smaller than 100 mesh obtained after the first granulation was greater than 400 mesh, which could be directly used as a barrier. Since 400 mesh corresponds to approximately 38 μm in particle size based on the relationship between mesh size and particle size, if this portion of micro-granulation consists of ceramic powder of approximately 38 μm (i.e., ungranulated raw material), and considering that finer ceramic powders have poorer flowability and lower viscosity, making granulation more difficult, there should still be ceramic powder particles smaller than 38 μm. However, the final particle size measured after granulation... The small particle size is about 38μm. It can be seen that this part of micro-granulation is obtained by granulating ceramic powder with a particle size of less than 38μm. It can be inferred that ceramic powder with a particle size of 20-80μm was basically granulated successfully, but granules with different particle size ranges were obtained. Although the particle size of the barrier used partially overlaps with the particle size of the ceramic powder raw material, the barrier is a granule obtained by granulating ceramic powder with a smaller particle size. Its physical properties are different from those of the raw ceramic powder. That is, the barrier and the ceramic powder are not the same.

[0065] Take 200g of the second batch of powder and add 65g of granules with a mesh size of 400-100 mesh obtained from the first granulation and sieving as a barrier. Mix the two together. Set the disc rotation speed to 30r / min during granulation and granulate for 3min. After granulation, sieve the granules into qualified and unqualified granules. Qualified granules are granules with a mesh size of 40-100 mesh, and unqualified granules are granules with a mesh size of 40-100 mesh and granules with a mesh size of 100 mesh or less. The second batch of 200g of powder yields 130g of granules with a mesh size of 40-100 mesh, 30g of granules with a mesh size of 40-100 mesh, and 40g of granules with a mesh size of 100 mesh or less. Compared to the first batch of powder, adding a barrier material of 400 mesh or higher and 100 mesh or lower can effectively prevent the powder from agglomerating into large balls after crushing, which is conducive to obtaining more qualified granules and reducing the formation of granules of 40 mesh or higher. That is, the yield of 40-100 mesh granules after a single granulation is 65%, the total yield is 51.25%, and the effective utilization rate of ceramic powder is 51.25%.

[0066] For the third granulation, 200g of the third batch of powder was taken, and 105g of granules with a mesh size of 400-100 mesh obtained from the first and second granulation and sieving were added as a barrier. The two were mixed, and the disc rotation speed was set to 30r / min during granulation for 3min. After granulation, the powder was sieved. The third batch of 200g of powder yielded 150g of granules with a mesh size of 40-100 mesh, 20g of granules with a mesh size of 40-100 mesh, and 30g of granules with a mesh size of 100-100 mesh. That is, the yield of granules with a mesh size of 40-100 mesh after a single granulation was 75%, and the total yield was 59.2%, which means that the effective utilization rate of ceramic powder was 59.2%.

[0067] Fourth granulation: Take 154g of the fourth batch of powder and add 135g of granules (400 mesh or finer than 100 mesh) obtained from the first, second, and third granulation sieving processes as a barrier. Mix the two together. During granulation, the disc rotation speed is set to 30r / min, and granulation takes 3min. After granulation, sieve the powder. The third batch of powder yields 134g of granules with a mesh size of 40-100 mesh, 16g of granules with a mesh size of 40 mesh or finer than 100 mesh, and 4g of granules with a mesh size of 100 mesh or finer than 100 mesh. That is, the yield of granules with a mesh size of 40-100 mesh after a single granulation is 87%, and the total yield is 64.85%, which means that the effective utilization rate of ceramic powder is 64.85%.

[0068] Fifth granulation: Take 265g of granules (above 40 mesh and below 100 mesh) obtained from the granulation of batches 1-4 and sieve them. Crush these granules to obtain 265g of powder, and add them to a disc granulator. During granulation, the disc speed is set to 20-40 r / min to avoid forming large balls. Granulation takes 3 minutes. After granulation, the granules are sieved into qualified and unqualified granules. Qualified granules are 40-100 mesh granules, and unqualified granules are granules above 40 mesh and below 100 mesh granules. The 265g of powder yields 105g of 40-100 mesh granules, 80g of 40 mesh and above, and 80g of below 100 mesh granules. That is, the yield of 40-100 mesh granules after a single granulation is 39.62%, and the total yield is 78.78%, meaning the effective utilization rate of ceramic powder is 78.78%.

[0069] The sixth granulation: 90g of granules with a mesh size of 40 or larger obtained from the fifth granulation were crushed to obtain 90g of powder. 80g of granules with a mesh size of 400 or larger but smaller than 100 mesh obtained from the fifth granulation were added as a barrier. After granulation of the 90g powder, the mass of granules with a mesh size of 40-100 mesh was 65g, the mass of granules with a mesh size of 40 or larger was 10g, and the mass of granules with a mesh size of less than 100 mesh was 5g. That is, the yield of granules with a mesh size of 40-100 mesh after a single granulation was 81.25%, and the total yield was 87.4%, which means that the effective utilization rate of ceramic powder was 87.4%.

[0070] The seventh granulation: 10g of granules larger than 40 mesh and 5g of granules smaller than 100 mesh obtained from the sixth granulation, and 80g of granules smaller than 100 mesh obtained from the fifth granulation, were crushed to obtain 95g of powder. This powder was then added to a disc granulator. The disc rotation speed was set to 20-40 r / min to avoid forming large spheres. Granulation lasted for 3 minutes. After granulation, the powder was sieved into qualified and unqualified granules. The mass of granules between 40 and 100 mesh was 40g, the mass of granules larger than 40 mesh was 35g, and the mass of granules smaller than 100 mesh was 20g. The yield of granules between 40 and 100 mesh after a single granulation was 42.1%, and the total yield was 92.7%, meaning the effective utilization rate of the ceramic powder was 92.7%.

[0071] The data from the BZT ceramic granulation process described above are summarized in the table below.

[0072] batch 1 2 3 4 5 6 7 Powder added / g 200 200 200 154 265 80 95 Barrier body / g 0 65 105 135 0 80 0 Granulation: 40-100 mesh / g 75 130 150 134 105 65 40 Granulation / g above 40 mesh 60 30 20 16 80 10 35 Granulation below 100 mesh / g 65 40 30 4 80 5 20 40-100 mesh granulation ratio 37.5％ 65％ 75％ 87％ 39.62％ 81.25％ 42.1％ Total yield of qualified granules (%) 37.5％ 51.25％ 59.2％ 64.85％ 78.78％ 87.40％ 92.7％

[0073] In the table, "qualified granules" refers to granules of 40-100 mesh, and the yield of granules of 40-100 mesh is calculated according to the following formula:

[0074]

[0075] After adding a barrier, the granules below 100 mesh after sieving are considered as the granules below 100 mesh obtained after granulation of the powder in that batch. For example, if 65g of barrier is added to 200g of powder in the second batch, after granulation and sieving, 135g of granules below 100 mesh are obtained. Of these, 65g of granules between 400 mesh and 100 mesh are the added barrier, and the remaining 40g are the granules below 100 mesh obtained after granulation of the powder in that batch.

[0076] Comparative Example 3

[0077] Barium zirconate titanate (BZT) ceramics are used as raw materials, with the chemical formula BaZr. x Ti 1-x O3, x = 0.1, including BaCO3, ZrO2, and TiO2, all with a purity of 99.99%, was ball-milled and dried, then crushed to obtain ceramic powder. The powder granulation steps are as follows:

[0078] Take 200g of the first batch of ceramic powder and add it to the disc granulator. Set the disc speed to 40r / min and granulate for 3min. After granulation, 60g of granules with a mesh size of 40 or larger, 65g of granules with a mesh size of 40-100, and 65g of granules with a mesh size of less than 100 are sieved. The yield of 40-100 mesh granules after a single granulation is 37.5%.

[0079] In the second batch, 200g of ceramic powder was taken and 60g of granules of 40 mesh or finer obtained from the first granulation and sieving were added as a barrier. The two were mixed and the disc rotation speed was set to 30r / min during granulation for 3min. After granulation, the mass of granules of 40 mesh or finer was 85g, the mass of granules of 40-100 mesh was 60g, and the mass of granules of less than 100 mesh was 55g. The yield of granules of 40-100 mesh after a single granulation was 30%, and the effective utilization rate of ceramic powder was 31.25%.

[0080] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for producing a granulated body based on ceramic powder, characterized by, Includes the following steps: The material is ceramic powder, and the barrier is made of micro-granules with a particle size of 400 mesh or more and a smooth surface of less than 100 mesh; the composition of the barrier is the same as that of the ceramic powder used as the raw material. The ceramic powder and the barrier are mixed and granulated by rolling granulation. After granulation, the granules are sieved to obtain granules with a particle size of 40 to 100 mesh.

2. The method for preparing granules based on ceramic powder as described in claim 1, characterized in that, The ceramic powder has a particle size of 20-80 μm.

3. The method for preparing granules based on ceramic powder as described in claim 2, characterized in that, The ceramic powder and the barrier were mixed at a mass ratio of 1:(0.2~1).

4. The method for preparing granules based on ceramic powder as described in claim 3, characterized in that, The barrier is a smooth-surfaced micro-granulation of the ceramic powder used as raw material, obtained by rolling granulation and sieving, with a particle size of 400 mesh or more and 100 mesh or less.

5. The method for preparing granules based on ceramic powder as described in claim 4, characterized in that, The ceramic powder is divided into n batches. The smooth-surfaced micro-granules with a particle size of 400 mesh or more and less than 100 mesh after granulation of the ceramic powder from the first batch to the (i-1)th batch are used as the barrier for granulation of the ceramic powder in the i-th batch, where i is 2, 3, ... n.

6. The method for preparing granules based on ceramic powder as described in claim 5, characterized in that, The method further includes re-grinding the granulated particles with a particle size of 40 mesh or larger and / or granulated particles with a particle size of 100 mesh or smaller after sieving to obtain ceramic powder, and then performing repeated granulation.

7. The method for preparing granules based on ceramic powder as described in claim 6, characterized in that, The ceramic powder is barium zirconate titanate ceramic powder, which includes BaCO3, ZrO2, and TiO2, with a purity of 99.9% or higher.

8. The method for preparing granules based on ceramic powder as described in claim 7, characterized in that, The rolling granulation uses a disc granulator, wherein the disc rotation speed is 20-40 r / min and the granulation time is 3-10 min.

9. A granulated body prepared from ceramic powder, characterized in that, Prepared according to the method described in any one of claims 1 to 8.

10. The use of a granulated body prepared by the method according to any one of claims 1 to 8 in the preparation of optical glass.

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