Method for preparing super-light ceramic granules by using molybdenum tailings, iron tailings and waste glass powder

Abstract

The application is a method for preparing super-light ceramic granules by using molybdenum tailings, iron tailings and waste glass powder. The super-light ceramic granules are prepared from raw materials in the following mass percentages: 40-70 parts of molybdenum tailings, 10-40 parts of iron tailings, and 5-20 parts of waste glass powder. Based on the total weight of the molybdenum tailings, iron tailings and waste glass powder, 0.3-0.5 wt.% of SiC is also added. After ball milling and sieving, the molybdenum tailings, iron tailings and waste glass powder are mixed uniformly with SiC, then water is added for granulation. After drying, sintering is performed to obtain super-light ceramic granules. The density of the super-light ceramic granules is less than 500 kg / m 3 , and the water absorption is less than 4%. By utilizing the mineral composition characteristics and chemical composition differences of molybdenum tailings, iron tailings and waste glass powder, super-light ceramic granules are prepared by sintering in cooperation. This method can effectively utilize waste resources such as molybdenum tailings, iron tailings and waste glass powder, and obtain super-light ceramic granules with a density of less than 500 kg / m 3 , and a water absorption of less than 4%.

Description

Technical Field

[0001] This invention relates to the field of ultralight ceramic particle preparation technology, and in particular to a method for preparing ultralight ceramic particles using molybdenum tailings, iron tailings and waste glass powder. Background Technology

[0002] Waste glass powder is a waste material generated during the grinding and processing of flat glass. The disposal of waste glass powder has always been a major problem for glass manufacturing and processing enterprises.

[0003] Ultra-lightweight expanded clay aggregate generally refers to aggregates with a density of 300-500 kg / m³. 3 Expanded clay aggregate (ECA) has the characteristics of low density, high strength, heat insulation, fire resistance, and earthquake resistance. It can replace ordinary sand and gravel in the preparation of thermal insulation concrete and products. It can also be used as water treatment filter media, adsorbents, permeable pavement materials, soilless cultivation culture media in agriculture and landscaping, as well as building materials such as bridge decks and hollow blocks. It has good application prospects.

[0004] Currently, there are studies on the preparation of ceramsite from molybdenum tailings and iron tailings. For example, CN202011535271.9 discloses a molybdenum tailings ceramsite and its preparation method. It uses molybdenum tailings, ceramic polishing waste powder, fly ash, limestone powder, cement, gypsum and alkali activator to prepare high-strength permeable building materials. Its water absorption rate is 4-6wt%, the composition is complex, and it cannot obtain ultra-light ceramsite.

[0005] For example, patent 202210777307.7 discloses a high-strength ceramsite made from low-silicon iron tailings. It is made from 75-90 parts of low-silicon iron tailings sand with a silica content of 25-30%, 5-15 parts of copper tailings sand with a silica content of 27-35.8%, and 5-15 parts of coal powder. The density grade is 800-1200, which cannot produce ultra-light ceramsite with low water absorption.

[0006] Therefore, this invention proposes a method for obtaining ultralight ceramic particles with low density and low water absorption that can achieve both ultralight material properties, using three types of solid waste: molybdenum tailings, iron tailings, and waste glass powder. This method is low in cost and has a simple formulation. Summary of the Invention

[0007] The purpose of this invention is to provide a method for preparing ultralight ceramsite using molybdenum tailings, iron tailings, and waste glass powder. This method utilizes the mineral composition characteristics and chemical composition differences of molybdenum tailings, iron tailings, and waste glass powder for synergistic sintering to prepare ultralight ceramsite, achieving effective utilization of waste resources such as molybdenum tailings, iron tailings, and waste glass powder, and obtaining particles with a density below 500 kg / m³. 3 At the same time, it is an ultra-lightweight ceramsite with a water absorption rate of less than 4%.

[0008] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0009] In a first aspect, the present invention provides a method for preparing ultralight ceramic granules using molybdenum tailings, iron tailings, and waste glass powder. The ultralight ceramic granules are prepared from raw materials in the following mass percentages: 40-70 parts molybdenum tailings, 10-40 parts iron tailings, and 5-20 parts waste glass powder. Based on the total weight of the molybdenum tailings, iron tailings, and waste glass powder, 0.3-0.5 wt.% SiC is also added. The molybdenum tailings, iron tailings, and waste glass powder are ball-milled, sieved, and then mixed evenly with SiC. After granulation with water, the mixture is dried and sintered to obtain ultralight ceramic granules with a density of less than 500 kg / m³. 3 The water absorption rate is less than 4%;

[0010] The sintering process is as follows: the temperature is increased to 400-600℃ at a heating rate of 5-15℃ / min, held for 10-30min, then increased to the sintering temperature of 1100-1140℃ at a heating rate of 5-15℃ / min, held for 10-30min, and then cooled to room temperature in the furnace.

[0011] Furthermore, the waste glass powder is waste generated during the grinding process of flat glass.

[0012] Furthermore, the ultralight ceramic particles contain a glass phase content of not less than 50% and a water absorption rate of less than 3%.

[0013] Furthermore, the specific steps of the method are as follows:

[0014] 1) The molybdenum tailings, iron tailings and waste glass powder were ball-milled separately and then passed through a 200-mesh sieve;

[0015] 2) Weigh out molybdenum tailings, iron tailings and waste glass powder according to mass percentage, add SiC pore-forming agent, and then ball mill for 20-60 minutes to mix them evenly to obtain mixed powder.

[0016] 3) Add 15-30% water (by weight of the mixed powder) to the mixed powder to form pellets with a particle size of 6-10 mm.

[0017] 4) Place the spherical blanks obtained in step 3) into an oven and dry them at 60-105℃ for 2-4 hours;

[0018] 5) Place the dried spherical blanks into a muffle furnace and heat them to 400-500℃ at a heating rate of 8-10℃ / min. Hold the temperature for 20-30 minutes, then heat them to the sintering temperature of 1100-1140℃ at a heating rate of 8-10℃ / min. Hold the temperature for 20-30 minutes and then cool them to room temperature with the furnace to obtain ultralight ceramic granules.

[0019] Secondly, the present invention provides an ultralight ceramic aggregate, wherein the raw material mass percentage of the ultralight ceramic aggregate is: 40-70 parts of molybdenum tailings, 10-40 parts of iron tailings, and 5-20 parts of waste glass powder.

[0020] Based on the total weight of molybdenum tailings, iron tailings, and waste glass powder, 0.3-0.5 wt.% SiC is also added;

[0021] The ultralight ceramic particles contain a glass phase content of not less than 50% by mass.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] This invention is the first to creatively prepare a material with a density of less than 500 kg / m³ using only molybdenum tailings, iron tailings, waste glass powder, and SiC as raw materials. 3 Ultra-lightweight ceramsite with a water absorption rate of less than 4%, preferably less than 3%, or even 1%, and a preferred sintering temperature of 1120℃. The use of three types of solid waste in the synergistic preparation of ultra-lightweight ceramsite maximizes the utilization of solid waste, reduces solid waste emissions, and effectively solves the problem of industrial solid waste pollution. It boasts low raw material costs and high added value, realizing the high-value application of molybdenum tailings, iron tailings, and waste glass powder. The compositions of molybdenum tailings, iron tailings, and waste glass powder are highly compatible with the raw material composition of ceramsite. Molybdenum tailings contain a large amount of silicon and aluminum, with a silicon content greater than 70%, which can serve as a skeleton component for ceramsite formation. Iron tailings and waste glass powder contain a large amount of alkali metals and alkaline earth metals, which can promote the formation of a high-temperature liquid phase, facilitating the expansion of ceramsite and reducing sintering temperature and energy consumption. The ultra-lightweight ceramsite of this invention has the characteristics of low density and low water absorption, and has broad application prospects in the fields of building thermal insulation and sound insulation.

[0024] The density of the ultralight ceramic granules in this invention is no greater than 500 kg / m³. 3 Furthermore, it is possible to obtain ultra-lightweight ceramic particles with even lower density, thus meeting the dual requirements of low density and low water absorption. In this invention, SiC is selected as the pore-forming agent, which can generate more gas during the sintering process. In the sintering system, the material is more likely to form balls, reducing the possibility of the generated gas escaping into the environment and retaining the gas inside the ceramic particles as much as possible, which is beneficial for obtaining low-density ultra-lightweight ceramic particles. Attached Figure Description

[0025] Figure 1 The images show the XRD patterns of the iron tailings, molybdenum tailings, and waste glass powder used in the examples.

[0026] Figure 2 These are images of the appearance and cross-sectional pore structure of the ultralight ceramic particles prepared in Examples 1-8.

[0027] Figure 3 This is the XRD pattern of the ultralight ceramic particles in Example 2. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this application clearer, a detailed description will be provided below with reference to specific embodiments. The embodiments described herein are merely some examples of this application and should not be construed as limiting the scope of protection of this application.

[0029] The raw materials for preparing ultralight ceramic particles according to the present invention include the following components by weight: 40-70 parts of molybdenum tailings, 10-40 parts of iron tailings, and 5-20 parts of waste glass powder. Based on the total weight of molybdenum tailings, iron tailings, and waste glass powder, 0.3% silicon carbide is also added.

[0030] For example, 40-70 parts of molybdenum tailings, such as 40 parts, 45 parts, 50 parts, 55 parts, 60 parts, 65 parts, or 70 parts, etc.

[0031] Iron tailings, 10-40 parts, for example, 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts or 40 parts.

[0032] 5-20 parts of waste glass powder, for example, 5 parts, 10 parts, 15 parts or 20 parts.

[0033] The main chemical composition (wt.%) of the raw materials in the following examples and comparative examples is shown in Table 1;

[0034] Table 1

[0035]

[0036] The density of the ceramsite was tested according to GB / T1966-1996 Test Method for Apparent Porosity and Bulk Density of Porous Ceramics, and the water absorption rate was tested according to GB / T17431.2-2010 Lightweight Aggregates and Their Test Methods Part 2: Test Methods for Lightweight Aggregates. The compressive strength was tested according to GB / T4740-1999 Test Method for Compressive Strength of Ceramic Materials.

[0037] Example 1

[0038] This embodiment utilizes a method for preparing ultralight ceramsite from molybdenum tailings, iron tailings, and waste glass powder. The raw material composition is 70 parts molybdenum tailings, 10 parts iron tailings, and 20 parts waste glass powder. Based on the total weight of the molybdenum tailings, iron tailings, and waste glass powder, 0.3 wt.% SiC is added. The preparation process is as follows:

[0039] (1) Drying and grinding: The crushed molybdenum tailings, iron tailings and waste glass powder are dried in an oven at 105℃ to constant weight. The dried materials are then put into a ball mill for grinding and passed through a 200-mesh sieve to obtain powder.

[0040] (2) Weighing: Weigh the molybdenum tailings, iron tailings and waste glass powder in a mass ratio of 7:1:2. In addition, weigh 0.3 wt.% of SiC, which is the sum of the masses of the first three.

[0041] (3) Mixing: Put the weighed powder into the ball mill and mix for 30 minutes.

[0042] (4) Molding: Add an appropriate amount of water to the mixed materials to form a ball blank.

[0043] (5) Drying: Place all the blanks in an oven at 105℃ and dry for 4 hours.

[0044] (6) Firing: The dried spherical blanks are placed in a muffle furnace and heated to 400°C at a heating rate of 10°C / min. The temperature is held for 20 min, and then heated to 1120°C at a heating rate of 10°C / min. The temperature is held for 30 min, and then cooled to room temperature with the furnace to obtain ultralight ceramic granules.

[0045] The density of the ultralight ceramsite produced in this embodiment was tested to be 482 kg / m³. 3 The water absorption rate is 0.24%.

[0046] Example 2

[0047] This embodiment utilizes a method for preparing ultralight ceramsite from molybdenum tailings, iron tailings, and waste glass powder. The raw material composition is 60 parts molybdenum tailings, 20 parts iron tailings, and 20 parts waste glass powder. Based on the total weight of the molybdenum tailings, iron tailings, and waste glass powder, 0.3 wt.% SiC is added. The preparation process is the same as in Example 1.

[0048] The density of the ultralight ceramsite produced in this embodiment was tested to be 427 kg / m³. 3 The water absorption rate is 0.30%.

[0049] Figure 3 The image shows the XRD pattern of the ultralight ceramic particles obtained in this embodiment. The glass phase mass ratio is calculated to be about 60% from the image and the software system.

[0050] Example 3

[0051] This embodiment utilizes a method for preparing ultralight ceramic particles from molybdenum tailings, iron tailings, and waste glass powder. The raw material composition is 50 parts of molybdenum tailings, 30 parts of iron tailings, and 20 parts of waste glass powder. Based on the total weight of molybdenum tailings, iron tailings, and waste glass powder, 0.3 wt.% SiC is added.

[0052] The density of the ultralight ceramsite produced in this embodiment was tested to be 408 kg / m³. 3 The water absorption rate is 0.43%.

[0053] Example 4

[0054] This embodiment utilizes a method for preparing ultralight ceramic particles from molybdenum tailings, iron tailings, and waste glass powder. The raw material composition is 40 parts of molybdenum tailings, 40 parts of iron tailings, and 20 parts of waste glass powder. Based on the total weight of molybdenum tailings, iron tailings, and waste glass powder, 0.3 wt.% SiC is added.

[0055] The density of the ultralight ceramsite produced in this embodiment was tested to be 382 kg / m³. 3 The water absorption rate is 0.85%. The proportion of the glass phase is relatively reduced to about 54%, and the viscosity of the glass phase is reduced.

[0056] Example 5

[0057] This embodiment utilizes a method for preparing ultralight ceramic particles from molybdenum tailings, iron tailings, and waste glass powder. The raw material composition is 70 parts of molybdenum tailings, 20 parts of iron tailings, and 10 parts of waste glass powder. Based on the total weight of molybdenum tailings, iron tailings, and waste glass powder, 0.3 wt.% SiC is added.

[0058] The density of the ultralight ceramsite produced in this embodiment was tested to be 496 kg / m³. 3 The water absorption rate is 0.19%.

[0059] Example 6

[0060] This embodiment utilizes a method for preparing ultralight ceramic particles from molybdenum tailings, iron tailings, and waste glass powder. The raw material composition is 60 parts of molybdenum tailings, 20 parts of iron tailings, and 20 parts of waste glass powder. Based on the total weight of molybdenum tailings, iron tailings, and waste glass powder, 0.3 wt.% SiC is added, and the sintering final temperature is 1140℃.

[0061] The density of the ultralight ceramsite produced in this embodiment was tested to be 328 kg / m³. 3 The water absorption rate is 1.96%.

[0062] Example 7

[0063] This embodiment utilizes a method for preparing ultralight ceramic particles from molybdenum tailings, iron tailings, and waste glass powder. The raw material composition is 40 parts of molybdenum tailings, 40 parts of iron tailings, and 20 parts of waste glass powder. Based on the total weight of molybdenum tailings, iron tailings, and waste glass powder, 0.3 wt.% SiC is added, and the sintering final temperature is 1130℃.

[0064] Tests showed that the density of the ultralight ceramic granules produced in this embodiment is 280 kg / m³. 3 The water absorption rate is 2.37%.

[0065] Example 8

[0066] This embodiment utilizes a method for preparing ultralight ceramic particles from molybdenum tailings, iron tailings, and waste glass powder. The raw material composition is 40 parts of molybdenum tailings, 40 parts of iron tailings, and 20 parts of waste glass powder. Based on the total weight of molybdenum tailings, iron tailings, and waste glass powder, 0.3 wt.% SiC is added, and the sintering final temperature is 1140℃.

[0067] Tests showed that the density of the ultralight ceramsite produced in this embodiment is 230 kg / m³. 3 The water absorption rate is 2.96%.

[0068] Comparative Example 1

[0069] The raw material composition for this comparative example is 100 parts of molybdenum tailings, with 0.3 wt.% SiC added based on the weight of the molybdenum tailings. The preparation process is as follows:

[0070] (1) Drying and grinding: The crushed molybdenum tailings are dried in an oven at 105℃ to constant weight. The dried material is then put into a ball mill for grinding and passed through a 200-mesh sieve to obtain powder.

[0071] (2) Weighing: Weigh the molybdenum tailings powder, and in addition, weigh 0.3 wt.% of SiC from the molybdenum tailings.

[0072] (3) Mixing: Put the weighed powder into the ball mill and mix for 30 minutes.

[0073] (4) Molding: Add an appropriate amount of water to the mixed materials to form a ball blank.

[0074] (5) Drying: Place all the blanks in an oven at 105℃ and dry for 4 hours.

[0075] (6) Firing: The dried spherical blanks are placed in a muffle furnace and heated to 400°C at a heating rate of 10°C / min. The temperature is held for 20 min, and then heated to 1120°C at a heating rate of 10°C / min. The temperature is held for 30 min, and then cooled to room temperature with the furnace to obtain ceramsite.

[0076] The density of the expanded clay aggregate produced in this comparative example was tested to be 1993 kg / m³. 3 The water absorption rate is 0.06%.

[0077] Comparative Example 2

[0078] The raw material composition of this comparative example is 100 parts of iron tailings, with 0.3 wt.% SiC added based on the weight of the iron tailings. The preparation process is the same as that of Comparative Example 1.

[0079] The density of the expanded clay aggregate produced in this comparative example was tested to be 2296 kg / m³. 3 The water absorption rate is 11.2%.

[0080] Comparative Example 3

[0081] The raw material composition of this comparative example is 80 parts of molybdenum tailings and 20 parts of waste glass powder. Based on the total weight of molybdenum tailings and waste glass powder, 0.3 wt.% SiC is added. The preparation process is the same as that of Comparative Example 1.

[0082] The density of the expanded clay aggregate produced in this comparative example was tested to be 921 kg / m³. 3 The water absorption rate is 0.34%.

[0083] Comparative Example 4

[0084] The raw material composition of this comparative example is 80 parts iron tailings and 20 parts waste glass powder. Based on the total weight of iron tailings and waste glass powder, 0.3 wt.% SiC is added.

[0085] The density of the expanded clay aggregate produced in this comparative example was tested to be 2514 kg / m³. 3 The water absorption rate is 4.51%.

[0086] Comparative Example 5

[0087] The raw material composition of this comparative example is 50 parts of molybdenum tailings and 50 parts of iron tailings, with 0.3 wt.% SiC added based on the total weight of the molybdenum tailings and iron tailings.

[0088] The density of the expanded clay aggregate produced in this comparative example was tested to be 1535 kg / m³. 3 The water absorption rate is 0.23%.

[0089] Table 2 shows a comparison of the performance of the ceramsite in the above embodiments and comparative examples.

[0090] Table 2

[0091]

[0092]

[0093] As can be seen from the above embodiments and comparative examples, under the same experimental conditions, molybdenum tailings, iron tailings and waste glass powder have a synergistic effect, and their performance is better than that of a single solid waste or the combination of two solid wastes, achieving a 1+1+1 greater than 3 effect. The method of the present invention obtains ultra-light ceramic particles with low water absorption and excellent performance, realizing the high-value utilization of molybdenum tailings, iron tailings and waste glass powder.

[0094] The appearance and cross-sectional pore structure of the ceramsite prepared in Examples 1-8 are as follows: Figure 2 As shown. From Figure 2It can be seen that when the ratio of molybdenum tailings, iron tailings, and waste glass powder is 6:2:2, the internal pore diameter of the ceramsite gradually increases and the density gradually decreases with increasing sintering temperature. When the sintering temperature is 1120℃, and the ratios of molybdenum tailings, iron tailings, and waste glass powder are 7:1:1 and 6:2:2, the internal pore diameter of the ceramsite is smaller and more uniformly distributed. However, when the ratios are 5:3:2 and 4:4:2, the internal pore diameter of the ceramsite increases, but the uniformity deteriorates. When the ratio of molybdenum tailings, iron tailings, and waste glass powder is 4:4:2 and the sintering temperature is 1140℃, the internal pore diameter of the ceramsite increases significantly, its density decreases, and its water absorption rate increases somewhat.

[0095] Furthermore, the compressive strength test revealed that the compressive strength of the ceramsite in this embodiment of the invention is approximately 1-6 MPa. The appropriate formula for ultralight ceramics can be selected based on the strength requirements of the actual application.

[0096] In the sintering process of the ceramsite in this invention, the sintering temperature cannot be too high, otherwise the pore structure will collapse; if the sintering temperature is too low, the ceramsite will not expand. The ratio of molybdenum tailings, iron tailings, and waste glass powder determines the amount and viscosity of the high-temperature liquid phase generated during sintering. If the amount of liquid phase generated is too small, it will not be enough to encapsulate the gas, and the ceramsite will not expand; if there is too much liquid phase and the viscosity is too low, it will cause the ceramsite to melt and collapse, filling the pore structure and increasing the density of the ceramsite. The raw material ratio and sintering temperature set in this application are more conducive to the uniformity of the internal pore structure of the ceramsite in this application. This low-density and low-water-absorption ultralight ceramic has more closed pores, which can play a very good role in thermal insulation, and therefore shows good application prospects in the fields of building thermal insulation and sound insulation.

[0097] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the implementation methods. For those skilled in the art, modifications or equivalent substitutions to the technical solutions of the present invention will not depart from the spirit and scope of the present invention, and all such modifications and substitutions should be covered within the scope of the claims.

[0098] Any aspects not covered in this invention are applicable to existing technologies.

Claims

1. A method for preparing ultralight ceramsite using molybdenum tailings, iron tailings, and waste glass powder, characterized in that, The ultralight ceramsite is prepared from the following raw materials in parts by weight: 40-70 parts molybdenum tailings, 10-40 parts iron tailings, and 5-20 parts waste glass powder. Based on the total weight of the molybdenum tailings, iron tailings, and waste glass powder, 0.3-0.5 wt.% SiC is also added. The molybdenum tailings, iron tailings, and waste glass powder are ball-milled, sieved, and then mixed evenly with SiC. After granulation with water, the mixture is dried and sintered to obtain ultralight ceramsite with a density of less than 500 kg / m³. 3 The water absorption rate is less than 4%; The sintering process is as follows: the temperature is increased to 400-600℃ at a heating rate of 5-15℃ / min, held for 10-30min, then increased to the sintering temperature of 1100-1140℃ at a heating rate of 5-15℃ / min, held for 10-30min, and then cooled to room temperature in the furnace.

2. The method for preparing ultralight ceramsite using molybdenum tailings, iron tailings, and waste glass powder according to claim 1, characterized in that, The waste glass powder mentioned is waste generated during the grinding process of flat glass.

3. The method for preparing ultralight ceramsite using molybdenum tailings, iron tailings, and waste glass powder according to claim 1, characterized in that, The ultralight ceramic particles contain a glass phase content of not less than 50% and a water absorption rate of less than 3%.

4. The method for preparing ultralight ceramsite using molybdenum tailings, iron tailings, and waste glass powder according to claim 1, characterized in that, The specific steps of the method are as follows: 1) The molybdenum tailings, iron tailings and waste glass powder were ball-milled separately and then passed through a 200-mesh sieve; 2) Weigh out molybdenum tailings, iron tailings and waste glass powder according to mass percentage, add SiC pore-forming agent, and then ball mill for 20-60 minutes to mix them evenly to obtain mixed powder. 3) Add 15-30% water (by weight of the mixed powder) to the mixed powder to form pellets with a particle size of 6-10 mm. 4) Place the spherical blanks obtained in step 3) into an oven and dry them at 60-105℃ for 2-4 hours; 5) Place the dried spherical blanks into a muffle furnace and heat them to 400-500℃ at a heating rate of 8-10℃ / min. Hold the temperature for 20-30 minutes, then heat them to the sintering temperature of 1100-1140℃ at a heating rate of 8-10℃ / min. Hold the temperature for 20-30 minutes and then cool them to room temperature with the furnace to obtain ultralight ceramic granules.

5. A type of ultralight ceramic aggregate, characterized in that, The raw material mass fractions of the ultralight ceramic granules are: 40-70 parts of molybdenum tailings, 10-40 parts of iron tailings, and 5-20 parts of waste glass powder. Based on the total weight of molybdenum tailings, iron tailings, and waste glass powder, 0.3-0.5 wt.% SiC is also added; The ultralight ceramic particles contain a glass phase content of not less than 50% by mass.

6. The ultralight ceramic aggregate according to claim 5, characterized in that, The chemical composition of molybdenum tailings, iron tailings, and waste glass powder, in mass percentage, is as follows: 。

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