Refractory solid waste recycled material and preparation method thereof

Abstract

The invention discloses a preparation method of a refractory solid waste regenerated material, which comprises the following steps: S1, crushing a waste refractory material to obtain crushed particles; s2, sieving the crushed particles to obtain regenerated particles smaller than or equal to 4 meshes, and re-treating the crushed particles larger than 4 meshes in the step S1; s3, sodium carboxymethyl cellulose, ball clay and an inorganic binder are added into the regenerated granules and stirred uniformly, and a refractory mixture is obtained; and S4, carrying out dry pressing molding on the mixture to obtain the refractory solid waste regenerated material. According to the preparation method of the refractory solid waste regenerated material, sodium carboxymethyl cellulose, ball clay and an inorganic binder are added to be stirred and mixed with regenerated granules, waste refractory materials can be reused to be made into regenerated refractory bricks, and land occupation caused by landfill of the waste refractory materials is avoided; and by adopting the method, the recycling rate of the refractory material is high, high-temperature preparation is not needed, and energy is saved.

Description

Technical Field

[0001] The invention relates to the technical field of waste refractory material recycling, and in particular to a refractory solid waste recycled material and a preparation method thereof. Background Art

[0002] When using refractory materials for kiln masonry in thermal engineering, the mortar joints of the kiln need to be precisely controlled. Generally, the mortar joints need to be less than 2mm. In special cases, the mortar joints are even required to be less than 1.5mm. Moreover, refractory materials require staggered paving. Therefore, before refractory materials are laid, they need to be cut, ground, and processed according to process requirements, and a large amount of waste refractory materials will be generated in the above process.

[0003] The amount of waste refractory materials generated each year is huge, and they are extremely difficult to handle and are extremely unfriendly to the environment. The typical treatment method for most waste refractory materials is landfill or reduced usage; this not only occupies precious land resources, but also causes waste of available resources and potential environmental pollution.

[0004] In the prior art, there are reports of attempts to add waste refractory materials into the raw materials of refractory materials for recycling. However, the waste refractory materials have a specific gravity of 0.6 to 1.0 g / cm 3 , which makes it light in weight but large in volume, and the long-distance transportation cost is high. The cost of recycling is greater than the benefits of processing waste refractory materials, making it difficult to promote. In addition, there are attempts to mix waste refractory materials into lightweight cement bricks, but this will cause dust problems in the production environment and reduce the strength of lightweight cement bricks, making them difficult to apply. Summary of the invention

[0005] The purpose of the present invention is to provide a refractory solid waste recycled material and a preparation method thereof to solve the above problems.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] The present invention provides a method for preparing a refractory solid waste recycled material, comprising the following steps:

[0008] S1: crushing the waste refractory materials to obtain crushed particles;

[0009] S2: Screening the crushed particles to obtain regenerated particles with a mesh size of less than or equal to 4, and re-processing the crushed particles with a mesh size of greater than 4 in step S1;

[0010] S3: adding sodium carboxymethyl cellulose, ball clay and inorganic binder to the recycled granular material, and stirring, and after stirring evenly, obtaining a refractory mixture;

[0011] S4: dry-pressing the mixture to obtain refractory solid waste recycled materials.

[0012] The preparation method of the refractory solid waste recycled material can reuse the waste refractory material into recycled refractory bricks by adding sodium carboxymethyl cellulose, ball clay and inorganic binder and stirring and mixing with the recycled granular material, thereby avoiding the occupation of land by landfilling the waste refractory material; and the use of this method makes the recycling rate of the refractory material higher, and the preparation method is simple, and no high-temperature preparation is required, which further saves energy and reduces manufacturing costs.

[0013] In the preparation method of the refractory solid waste recycled material, in the screening process of step S2, the broken particles are screened into large broken particles, medium broken particles, small broken particles and fine broken particles; the mesh number of the large broken particles is 4 mesh to 10 mesh, the mesh number of the medium broken particles is 10 mesh to 20 mesh, the mesh number of the small broken particles is 20 mesh to 60 mesh, and the mesh number of the fine broken particles is less than 60 mesh;

[0014] Then, according to the weight proportion, 40 to 45 parts of large crushed particles, 25 to 30 parts of medium crushed particles, 20 to 25 parts of small crushed particles and 10 to 15 parts of fine crushed particles are mixed to obtain recycled granular material.

[0015] In the method for preparing the refractory solid waste recycled material, the inorganic binder is a silicate binder or bauxite clay.

[0016] In the preparation method of the refractory solid waste recycled material, the refractory mixture includes, by weight percentage, 0.1 to 0.5 parts of sodium carboxymethyl cellulose, 2 to 5 parts of ball clay, 5 to 15 parts of inorganic binder and 49 to 90 parts of recycled granular material.

[0017] In the method for preparing the refractory solid waste recycled material, in step S4, the pressure range of the dry pressing is 25 to 27 MPa.

[0018] In the method for preparing the refractory solid waste recycled material, in step S4, after the dry pressing, the refractory solid waste recycled material is further subjected to a curing treatment.

[0019] In the preparation method of the refractory solid waste recycled material, the curing temperature is 25 to 35° C., the curing humidity is ≥ 60%, and the curing time is 3 to 7 days.

[0020] The present invention also provides a refractory solid waste recycled material, which is prepared using the above-mentioned method for preparing the refractory solid waste recycled material.

[0021] A technical solution in the present invention can have the following beneficial effects:

[0022] The preparation method of the refractory solid waste recycled material can reuse the waste refractory material into recycled refractory bricks by adding sodium carboxymethyl cellulose, ball clay and inorganic binder and stirring and mixing with the recycled granular material, thereby avoiding the occupation of land by landfilling the waste refractory material; and the use of this method makes the recycling rate of the refractory material higher, and the preparation method is simple, and no high-temperature preparation is required, which further saves energy and reduces manufacturing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the appearance of the refractory solid waste recycled material according to Example 1 of the present invention;

[0024] Figure 2 It is a schematic diagram of the appearance of the refractory solid waste recycled material of Comparative Example 1 in the present invention. DETAILED DESCRIPTION

[0025] The technical scheme of the present invention is further illustrated by specific embodiments below. In order to facilitate understanding of the present invention, the present invention is described more comprehensively below. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0026] If no specific techniques or conditions are specified in the examples, the techniques or conditions described in the literature in the field or the product instructions are used. If no manufacturer is specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0028] The present invention provides a method for preparing a refractory solid waste recycled material, comprising the following steps:

[0029] S1: crushing the waste refractory materials to obtain crushed particles;

[0030] S2: Screening the crushed particles to obtain regenerated particles with a mesh size of less than or equal to 4, and re-processing the crushed particles with a mesh size of greater than 4 in step S1;

[0031] S3: adding sodium carboxymethyl cellulose, ball clay and inorganic binder to the recycled granular material, and stirring, and after stirring evenly, obtaining a refractory mixture;

[0032] S4: dry-pressing the mixture to obtain refractory solid waste recycled materials.

[0033] The waste refractory materials are waste materials generated during the cutting or grinding process of refractory materials. The volume of the waste materials generated by cutting or grinding is 3 to 4 times that of the refractory materials under the same mass. The specific gravity of the waste materials generated by cutting or grinding is relatively light. If they are directly mixed into the components of refractory materials to produce refractory materials, the specific gravity of the refractory materials will be reduced, the physical properties of the refractory materials will be reduced, and the use of the refractory materials will be affected.

[0034] The preparation method of the refractory solid waste recycled material can reuse the waste refractory material into recycled refractory bricks by adding sodium carboxymethyl cellulose, ball clay and inorganic binder and stirring and mixing with the recycled granular material, thereby avoiding the occupation of land by landfilling the waste refractory material; and the use of this method makes the recycling rate of the refractory material higher, and the preparation method is simple, and no high-temperature preparation is required, which further saves energy and reduces manufacturing costs.

[0035] The waste refractory materials are crushed in step S1 to be pulverized into particles, which are convenient for subsequent mixing with sodium carboxymethyl cellulose, ball clay and inorganic binder.

[0036] The crushed particles are screened in step S2 so that the crushed particles with too large particle size are re-crushed, and the regenerated particles with a size less than or equal to 4 mesh obtained by screening are processed in step S3.

[0037] The recycled granular material is mixed with sodium carboxymethyl cellulose, ball clay and an inorganic binder through step S3, and the recycled granular material and the ball clay are combined together by sodium carboxymethyl cellulose and the inorganic binder to enhance the plasticity and operability of the material during the molding process, so that the refractory solid waste recycled material can be pressed into a desired shape during the production process.

[0038] Through the dry pressing in step S4, the refractory mixture can be pressed into various specifications such as 115×230×60, 230×230×98, etc. to meet the needs of different customers.

[0039] Specifically, in the screening process of step S2, the broken particles are screened into large broken particles, medium broken particles, small broken particles and fine broken particles; the mesh number of the large broken particles is 4-10 meshes, the mesh number of the medium broken particles is 10-20 meshes, the mesh number of the small broken particles is 20-60 meshes, and the mesh number of the fine broken particles is less than 60 meshes;

[0040] Then, according to the weight proportion, 40 to 45 parts of large crushed particles, 25 to 30 parts of medium crushed particles, 20 to 25 parts of small crushed particles and 10 to 15 parts of fine crushed particles are mixed to obtain recycled granular material.

[0041] The combination ratios of the four types of granules, namely large crushed particles, medium crushed particles, small crushed particles and fine crushed particles, are different, and the final reclaimed granules have different bulk densities and large differences in compression ratio. The particle size of fine crushed particles is too small, and the fine particles are easy to fill in the tiny gaps of the mold. Although a dense structure can be formed, if the binder or curing is insufficient, it will lead to over-compaction in some areas and looseness in other areas. The molded body may become fragile and easy to break, affecting the final strength and consistency of the product.

[0042] Therefore, in the preparation method, nearly half of the broken particles of 4-10 mesh are used as the main body, and the broken particles of 10-20 mesh, 20-60 mesh and the broken particles with a mesh number less than 60 mesh are mixed, wherein the content of medium broken particles, small broken particles and fine broken particles is gradually reduced. With the above ratio, large broken particles, medium broken particles, small broken particles and fine broken particles can cooperate with each other, and fine broken particles can fill in the gaps that may exist between larger particles, and the particles are in close contact, which is convenient for compaction, reduces the molding pressure required in the dry pressing process, and ensures the strength of the refractory solid waste recycled material.

[0043] Specifically, the inorganic binder is a silicate binder or bauxite cement.

[0044] In a specific embodiment of the present invention, the bauxite mortar has high adhesion and plasticity, can combine the recycled granular material with the ball clay, and can maintain its shape at a relatively high temperature, and has good high temperature resistance.

[0045] Silicate binders include one of aluminum silicate, cement-based binder and calcium silicate, and form strong bonding force at room temperature.

[0046] Specifically, the refractory mixture includes, by weight, 0.1 to 0.5 parts of sodium carboxymethyl cellulose, 2 to 5 parts of ball clay, 5 to 15 parts of inorganic binder and 49 to 90 parts of recycled granular material.

[0047] Ball clay has good plasticity, which can help refractory materials to be shaped more easily during the forming process. Moreover, the structure and chemical properties of ball clay are stable, and it can maintain good chemical and physical properties at high temperatures, thereby improving the high-temperature oxidation resistance and corrosion resistance of refractory materials.

[0048] Inorganic binders are usually used to bind recycled particles together, enhance the plasticity and operability of the material during the molding process, enable the refractory solid waste recycled materials to be pressed into the desired shape during the production process, and ensure that the refractory solid waste recycled materials are not easy to disintegrate during molding.

[0049] Recycled granular material is the main component of refractory solid waste recycled material. After being mixed with ball clay, sodium carboxymethyl cellulose and inorganic binder and pressed, it can meet the requirements of existing refractory materials.

[0050] Specifically, in step S4, the pressure range of dry pressing is 25-27 MPa.

[0051] Through the above-mentioned high pressure, the refractory mixture can be compacted, so that it can better maintain its shape and enhance its physical and chemical properties.

[0052] Furthermore, in step S4, after dry pressing, the refractory solid waste recycled material is also subjected to curing treatment.

[0053] The curing process can prevent the refractory solid waste recycled materials from deformation, warping or cracking due to changes in environmental humidity and temperature, and help the refractory solid waste recycled materials maintain their original shape and size and extend their service life. At the same time, increase compressive strength and toughness: Refractory solid waste recycled materials that have been properly cured are more durable during use, have stronger compressive resistance and toughness, and are not easily damaged by external forces.

[0054] Furthermore, the curing temperature is 25-35° C., the curing humidity is ≥60%, and the curing time is 3-7 days.

[0055] Using the above-mentioned curing temperature and humidity, after 3 to 7 days of curing, the strength requirements for cutting and kiln masonry can be met.

[0056] The present invention also provides a refractory solid waste recycled material, which is prepared using the above-mentioned method for preparing the refractory solid waste recycled material.

[0057] The permissible use temperature limit of the refractory solid waste recycled material prepared by the above preparation method is 1250°C, and the material density is 1.1-1.3g / cm 3 , average specific heat 0.9~1.1kj / kg·℃, thermal conductivity 0.6~0.7W / m·℃.

[0058] The refractory temperature limit, high-temperature reburning shrinkage rate and thermal conductivity of the above-mentioned refractory solid waste recycled materials all meet the refractory process requirements and can partially replace traditional refractory materials, which not only reduces resource consumption but also protects environmental pollution.

[0059] Example Group A

[0060] A method for preparing a refractory solid waste recycled material comprises the following steps:

[0061] Crushing the waste refractory materials to obtain crushed particles;

[0062] The broken particles are screened into large broken particles, medium broken particles, small broken particles and fine broken particles; the mesh number of the large broken particles is 4-10 meshes, the mesh number of the medium broken particles is 10-20 meshes, the mesh number of the small broken particles is 20-60 meshes, and the mesh number of the fine broken particles is less than 60 meshes;

[0063] Then, according to the proportions in Table 1, large crushed particles, medium crushed particles, small crushed particles and fine crushed particles are mixed to obtain recycled granular materials, and crushed particles larger than 4 mesh are processed again in step S1;

[0064] According to the proportions in Table 1, the recycled granular material, sodium carboxymethyl cellulose, ball clay and inorganic binder are mixed and stirred until evenly mixed to obtain a refractory mixture;

[0065] S4: dry-pressing the mixture to obtain refractory solid waste recycled materials.

[0066] Table 1- Ratio and other parameters

[0067]

[0068] in, Figure 1 This is a schematic diagram of the appearance of the refractory solid waste recycled material of Example 1.

[0069] Comparative Example 1

[0070] A method for preparing a refractory solid waste recycled material comprises the following steps:

[0071] The ceramic wool waste is crushed and sieved to obtain ceramic wool recycled granular material less than or equal to 4 mesh;

[0072] Adding sodium carboxymethyl cellulose, ball clay and an inorganic binder to the ceramic wool recycled granular material, and stirring the mixture until it is uniformly stirred to obtain a refractory mixture;

[0073] The mixture is dry-pressed and cured at a temperature of 25° C., a humidity of 90%, and a curing time of 7 days to obtain ceramic cotton solid waste recycled materials. Figure 2 This is a schematic diagram of the appearance of the refractory solid waste recycled material of Example 1.

[0074] Comparative Example 2

[0075] The preparation steps of Comparative Example 2 are the same as those of Example 1, except that the recycled granular material of Comparative Example 2 is crushed to 6-10 mesh.

[0076] Comparative Example 3

[0077] The preparation steps of Comparative Example 3 are the same as those of Example 1, except that, in step S2 of Comparative Example 3, 10 to 15 parts of large crushed particles, 25 to 30 parts of medium crushed particles, 20 to 25 parts of small crushed particles and 40 to 45 parts of fine crushed particles are mixed to obtain recycled granular material.

[0078] The refractory solid waste recycled materials obtained in Example Group A, Comparative Examples 2 and 3 and the ceramic wool solid waste recycled materials obtained in Comparative Example 1 were observed, and the material density, average specific heat, thermal conductivity and extreme temperature 1250°C / 24h firing experiments were conducted, and the results are shown in Table 2. The extreme temperature 1250°C / 24h firing experiment steps are as follows: placing the refractory solid waste recycled materials or the ceramic wool solid waste recycled materials in a kiln for 5 to 6 hours, heating them to 1250°C, and then keeping them warm for 24 hours; after cooling to room temperature, taking out the samples for observation, and checking whether the shrinkage rate is less than 0.5%.

[0079] Table 2 - Test results

[0080]

[0081]

[0082] According to the results in Table 2, the allowable use temperature limit of the refractory solid waste recycled material prepared by the above preparation method is 1250°C, and the material density is 1.1-1.3 g / cm 3 , average specific heat 0.9 ~ 1.1 kj / kg · ° C, thermal conductivity 0.6 ~ 0.7 W / m · ° C. Comparative Example 1 uses ceramic cotton waste as raw material, and the effect is poor compared with the present application. The fineness of the recycled particles in Comparative Example 2 is large, resulting in poor compression effect. In Comparative Example 3, the amount of large crushed particles used is small, and the amount of fine crushed particles used is large, which is not conducive to compaction, resulting in poor overall performance of refractory solid waste recycled materials.

[0083] Moreover, by comparison Figure 1 and Figure 2 It can be seen that the refractory solid waste recycled material prepared by the above preparation method is more dense.

[0084] The technical principle of the present invention is described above in conjunction with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the scope of protection of the present invention in any way. Based on the explanations herein, those skilled in the art can associate other specific embodiments of the present invention without creative work, and these equivalent variations or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A method for preparing refractory solid waste recycled materials, characterized in that: The following steps are involved: S1: crushing the waste refractory materials to obtain crushed particles; S2: Screening the crushed particles to obtain regenerated particles with a mesh size of less than or equal to 4, and re-processing the crushed particles with a mesh size of greater than 4 in step S1; S3: adding sodium carboxymethyl cellulose, ball clay and inorganic binder to the recycled granular material, and stirring, and after stirring evenly, obtaining a refractory mixture; S4: dry-pressing the mixture to obtain refractory solid waste recycled materials.

2. The method for preparing a refractory solid waste recycled material according to claim 1, characterized in that: In the screening process of step S2, the broken particles are screened into large broken particles, medium broken particles, small broken particles and fine broken particles; the mesh number of the large broken particles is 4-10 meshes, the mesh number of the medium broken particles is 10-20 meshes, the mesh number of the small broken particles is 20-60 meshes, and the mesh number of the fine broken particles is less than 60 meshes; Then, according to the weight proportion, 40 to 45 parts of large crushed particles, 25 to 30 parts of medium crushed particles, 20 to 25 parts of small crushed particles and 10 to 15 parts of fine crushed particles are mixed to obtain recycled granular material.

3. The method for preparing a refractory solid waste recycled material according to claim 1, characterized in that: The inorganic binder is a silicate binder or alumina cement.

4. The method for preparing a refractory solid waste recycled material according to claim 1, characterized in that: The refractory mixture comprises, by weight percentage, 0.1 to 0.5 parts of sodium carboxymethyl cellulose, 2 to 5 parts of ball clay, 5 to 15 parts of inorganic binder and 49 to 90 parts of recycled granular material.

5. The method for preparing a refractory solid waste recycled material according to claim 1, characterized in that: In step S4, the pressure range of dry pressing is 25-27 MPa.

6. The method for preparing a refractory solid waste recycled material according to claim 1, characterized in that: In step S4, after dry pressing, the refractory solid waste recycled materials are also subjected to curing treatment.

7. The method for preparing refractory solid waste recycled materials according to claim 6, characterized in that: The curing temperature is 25-35° C., the curing humidity is ≥60%, and the curing time is 3-7 days.

8. A refractory solid waste recycled material, characterized in that: The refractory solid waste recycled material is prepared using the method for preparing the refractory solid waste recycled material according to any one of claims 1 to 7.

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