Method for preparing rock wool from automobile exhaust catalyst smelting tailings and thermal insulation material

Abstract

The invention discloses a method for preparing rock wool from automobile exhaust catalyst smelting tailings and a thermal insulation material. A method for preparing rock wool from automobile exhaust catalyst smelting tailings comprises the following steps that the tailings and a hardening and tempering agent are ground and mixed evenly in proportion, the mass ratio of the tailings to the hardening and tempering agent is 100: (2-13), the materials are heated to be in a molten state completely, a melt is obtained and centrifuged to generate fibers, the fibers are collected, and the rock wool is obtained; the tailings comprise CaO, SiO2, Al2O3, MgO, B2O3 and a platinum group metal oxide. The tailings further comprise heavy metal oxides, and heavy metals comprise one or more of zinc, barium, mercury or cadmium. The particle size of the tailings and the particle size of the tempering agent do not exceed 500 microns. The rock wool fiber with good performance is prepared, and the thermal insulation material plate is prepared on the basis of the rock wool fiber, so that recycling of waste resources is facilitated, and the production cost is remarkably reduced.

Description

Technical Field

[0001] The present application relates to the technical field of comprehensive utilization of waste resources, and in particular to a method for preparing rock wool from automobile exhaust catalyst smelting tailings and a thermal insulation material. Background Art

[0002] Platinum group metals are widely used in industry, especially in the catalyst industry, due to their excellent physical and chemical properties. After the service life of automobile exhaust catalysts is exhausted, the platinum group metals as catalytic components are still attached to the surface of the carrier. Therefore, waste automobile exhaust catalysts are regarded as important secondary resources of platinum group metals. Fire recovery is widely used because of its wide range of materials and simple process. The random stacking of the generated smelting tailings will cause a large amount of land resources to be wasted, so it is necessary to make high-value secondary utilization of the tailings.

[0003] The molten tailings are prepared into slag fibers, which have the advantages of light weight and good thermal insulation effect. In recent years, slag fiber boards have been widely used as thermal insulation materials. Common thermal insulation materials are generally made of natural rocks (such as basalt, diabase, etc.) as the main raw materials, which are melted at high temperature and then made into fiber materials by high-speed centrifugation and process treatment. For example, the patent document with application number 201810390756.X uses basalt and shale as the main raw materials, supplemented by glass slag to prepare thermal insulation materials. The patent document with application number 202410425282.3 uses 40% to 50% basalt as the raw material for preparing thermal insulation materials. It not only increases the production cost, but also the utilization rate of waste slag is not ideal. In addition, the waste slag produced by smelting waste automobile exhaust catalysts contains a large amount of harmful metals. Failure to carry out secondary treatment not only causes a waste of resources but also harms the environment.

[0004] The waste residue obtained from the smelting of waste automobile exhaust catalysts is treated for a second time and used as the main raw material for the production of new insulation materials, which not only saves a lot of resources but also reduces production costs, fully following the principle of circular economy. In summary, the secondary utilization of automobile exhaust catalyst smelting tailings is one of the main research directions in this field. Summary of the invention

[0005] In view of this, the purpose of the present application is to provide a method for preparing rock wool from automobile exhaust catalyst smelting tailings, which can effectively solve the problem of automobile exhaust catalyst smelting tailings disposal.

[0006] This application provides the following technical solutions:

[0007] A method for preparing rock wool from automobile exhaust catalyst smelting tailings, comprising the following steps: grinding the tailings and a conditioning agent respectively and mixing them evenly in proportion, wherein the mass ratio of the tailings to the conditioning agent is 100:(2-13), heating the material to completely melt it to obtain a melt, centrifuging it to generate fibers, and collecting the fibers to obtain rock wool;

[0008] The tailings include CaO, SiO2, Al2O3, MgO, B2O3 and platinum group metal oxides.

[0009] Preferably, the tailings further include heavy metal oxides, and the heavy metals include one or more of zinc, barium, mercury or cadmium.

[0010] Preferably, the particle size of the tailings and the conditioning agent does not exceed 500 μm.

[0011] Preferably, the conditioning agent is limestone or silica.

[0012] Preferably, the material is heated to a temperature of 1400 to 1500° C. and is kept warm for 15 to 30 minutes after heating.

[0013] Preferably, the acidity of the rock wool is 1.1 to 1.7. k The calculation is as follows:

[0014]

[0015] Preferably, the acidity of the rock wool is 1.1-1.4.

[0016] A thermal insulation material comprises the rock wool board obtained by the method for preparing rock wool from automobile exhaust catalyst smelting tailings.

[0017] Preferably, the rock wool is added with a binder and a waterproofing agent and solidified to obtain a thermal insulation material.

[0018] The present application uses the tailings obtained by smelting waste automobile exhaust catalysts to recover platinum group metals as the main raw material to prepare thermal insulation materials, and mixes them with silica or limestone in a suitable ratio without adding other raw materials, to obtain rock wool fibers with good performance and prepare thermal insulation material boards on this basis, which is conducive to the recycling of waste resources and significantly reduces production costs. Specifically, on the one hand, if a special treatment method is used for the treatment of automobile exhaust catalyst smelting tailings, it will undoubtedly bring high costs. On the other hand, according to the method of the present application, the automobile exhaust catalyst smelting tailings are used to prepare high-performance thermal insulation materials, which not only realizes the recycling of waste resources, but also, compared with other waste slags, the present application does not need to add other raw materials, the utilization rate of the tailings is higher, the production cost is low, and the potential harm caused by the tailings to the environment and resources is eliminated while increasing the benefits, and the practicality is high.

[0019] In the process of adjusting the acidity of tailings in the present application, the mineral wool is in an amorphous glass state, and harmful metals are wrapped in the amorphous network structure of the mineral wool and are difficult to be leached out.

[0020] The thermal insulation material of the present application has better performance, including better thermal insulation performance, high strength, better fire resistance, lower material moisture absorption rate, lower cost, and easy to obtain raw materials. DETAILED DESCRIPTION

[0021] The technical solution of the present application will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0022] A method for preparing rock wool from automobile exhaust catalyst smelting tailings, comprising the following steps: grinding the tailings and the tempering agent respectively, wherein the particle size of the tailings and the tempering agent does not exceed 300 μm, and mixing them evenly in proportion, wherein the mass ratio of the tailings and the tempering agent is 100:(2-13), and the tempering agent is limestone or silica. Heating the material to completely enter a molten state to obtain a melt, wherein the heating temperature is 1400-1500°C, wherein 1500°C is preferred, and the melt is kept warm for 30 minutes after heating to homogenize the melt, the purpose of which is to ensure the fiber formation rate of the fiber. The melt is centrifuged to generate fibers, and the fibers are collected in a cotton collecting chamber to obtain rock wool, wherein the acidity of the rock wool is 1.1-1.7, wherein 1.1-1.4 is preferred, and when the acidity of the rock wool is 1.1-1.4, the thermal insulation performance is better, the strength is high, the fire resistance is better, and the material moisture absorption rate is lower. Adding a binder and a waterproofing agent to the rock wool, and curing it through a curing furnace to make it a plate of a certain thickness, thereby obtaining a rock wool board.

[0023] The tailings include CaO, SiO2, Al2O3, MgO, B2O3 and platinum group metal oxides.

[0024] The tailings also include heavy metal oxides, including one or more of zinc, barium, mercury or cadmium. In the process of adding the tempering agent to obtain the melt, the mass transfer resistance of the heavy metal increases, and as the fluidity of the melt increases, it is conducive to the agglomeration of particles, thereby inhibiting the volatilization of heavy metals.

[0025] Example 1

[0026] The main components of the tailings in this example are shown in Table 1.

[0027] A method for preparing rock wool from automobile exhaust catalyst smelting tailings comprises the following steps: grinding tailings and limestone respectively, wherein the particle size of tailings and conditioning agent is 500 μm. 50 kg of tailings and 6.5 kg of limestone are mixed evenly. The material is heated to completely enter a molten state to obtain a melt, the heating temperature is 1500° C., and the heat is kept for 30 minutes after heating. The hot melt is poured out and a four-roll centrifuge is opened to fiberize the slag, and the fibers are collected in a cotton collecting chamber to obtain rock wool, wherein the acidity of the rock wool is 1.1.

[0028] The formed cotton felt is obtained by a pendulum device, a binder phenolic resin and a polyurethane waterproofing agent are added, and the felt is cured in a curing furnace to obtain a rock wool board.

[0029] Example 2

[0030] The main components of the tailings in this embodiment are the same as those in Example 1.

[0031] A method for preparing rock wool from automobile exhaust catalyst smelting tailings, the steps are the same as those in Example 1, except that 50 kg of tailings and 4.5 kg of limestone are used.

[0032] Example 3

[0033] The main components of the tailings in this embodiment are the same as those in Example 1.

[0034] A method for preparing rock wool from automobile exhaust catalyst smelting tailings, the steps are the same as those in Example 1, except that 50 kg of tailings and 2.5 kg of limestone are used.

[0035] Example 4

[0036] The main components of the tailings in this embodiment are the same as those in Example 1.

[0037] A method for preparing rock wool from automobile exhaust catalyst smelting tailings, the steps are the same as those in Example 1, except that 50 kg of tailings and 1 kg of limestone are used.

[0038] Example 5

[0039] The main components of the tailings in this embodiment are the same as those in Example 1.

[0040] A method for preparing rock wool from automobile exhaust catalyst smelting tailings, the steps are the same as those in Example 1, except that 50 kg of tailings and 1 kg of silica are used.

[0041] Example 6

[0042] The main components of the tailings in this embodiment are the same as those in Example 1.

[0043] A method for preparing rock wool from automobile exhaust catalyst smelting tailings, the steps are the same as those in Example 1, except that 50 kg of tailings and 3 kg of silica are used.

[0044] Example 7

[0045] The main components of the tailings in this embodiment are the same as those in Example 1.

[0046] A method for preparing rock wool from automobile exhaust catalyst smelting tailings, the steps are the same as those in Example 1, except that 50 kg of tailings and 5 kg of silica are used.

[0047] The main components (wt%) of tailings and thermal insulation materials in each embodiment are shown in Table 1.

[0048] Table 1

[0049] product CaO <![CDATA[SiO2]]> <![CDATA[Al2O3]]> MgO <![CDATA[B2O3]]> Acidity coefficient Tailings 35.10 43.86 9.40 5.64 6.00 1.45 Example 1 42.65 38.76 8.31 4.98 5.30 1.1 Example 2 40.28 40.36 8.65 5.19 5.52 1.2 Example 3 38.11 41.82 8.96 5.38 5.72 1.3 Example 4 36.13 43.16 9.25 5.55 5.90 1.4 Example 5 34.46 44.88 9.23 5.54 5.89 1.5 Example 6 33.15 46.98 8.88 5.32 5.67 1.6 Example 7 31.92 49.89 8.55 5.13 5.46 1.7

[0050] Comparative Example

[0051] The commercially available thermal insulation material has the following components: SiO2: 41.6wt%; Al2O3: 14.7wt%; CaO: 23.4wt%; MgO: 11.5wt%.

[0052] The rock wool boards obtained in Examples 1 to 7 and the comparative example materials were tested for their performance according to GB / T5480-2008. The thickness of each group of tested materials was the same, which was 50 mm. The test results are shown in Table 2.

[0053] Table 2

[0054]

[0055] In the table, diameter refers to the diameter of mineral wool fibers. Slag ball refers to an irregular, large solid particle caused by incomplete high-temperature melting or uneven raw materials during the production of rock wool. It usually presents a spherical or irregular shape and is mainly composed of mineral impurities. The calculation method is: Slag ball content = [(slag ball mass) / (sample mass)] × 100%.

[0056] The above materials all comply with GB / T5480-2008. It can be seen from the data in Table 2 that the new thermal insulation material has better performance than the traditional rock wool thermal insulation material on the market. Specifically, the slag ball content of the embodiment is lower. Too high a slag ball content will lead to poor thermal insulation performance, reduced strength, poor fire resistance and other problems of rock wool. The thermal conductivity is smaller, the thermal insulation effect is better, the mass moisture absorption rate is lower, the cost is lower, and the raw materials are easier to obtain.

[0057] The above embodiments focus on the differences from other embodiments, and the same or similar parts between the various embodiments can be referenced to each other.

[0058] The above description of the disclosed embodiments enables professionals in the field to implement or use the present application. Various modifications to these embodiments will be apparent to professionals in the field, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. The embodiments are merely examples for clearly illustrating the technical solutions of the present application, and are not intended to limit the present application.

Claims

1. A method for preparing rock wool from automobile exhaust catalyst smelting tailings, characterized in that: The following steps are involved: The tailings and the conditioning agent are ground separately and mixed evenly in proportion, wherein the mass ratio of the tailings to the conditioning agent is 100:(2-13), the materials are heated to completely melt, a melt is obtained, the melt is centrifuged to generate fibers, and the fibers are collected to obtain rock wool; The tailings include CaO, SiO2, Al2O3, MgO, B2O3 and platinum group metal oxides.

2. The method for preparing rock wool from automobile exhaust catalyst smelting tailings according to claim 1, characterized in that: The tailings also include heavy metal oxides, and the heavy metals include one or more of zinc, barium, mercury or cadmium.

3. The method for preparing rock wool from automobile exhaust catalyst smelting tailings according to claim 1, characterized in that: The particle sizes of the tailings and the conditioning agent are both less than 500 μm.

4. The method for preparing rock wool from automobile exhaust catalyst smelting tailings according to claim 1, characterized in that: The conditioning agent is limestone or silica.

5. The method for preparing rock wool from automobile exhaust catalyst smelting tailings according to claim 1, characterized in that: The heating temperature of the material is 1400-1500° C., and the material is kept warm for 15-30 minutes after heating.

6. The method for preparing rock wool from automobile exhaust catalyst smelting tailings according to claim 1, characterized in that: The acidity of the rock wool is 1.1 to 1.

7.

7. The method for preparing rock wool from automobile exhaust catalyst smelting tailings according to claim 6, characterized in that: The acidity of the rock wool is 1.1 to 1.

4.

8. A thermal insulation material, characterized in that: The rock wool comprises the rock wool obtained by the method for preparing rock wool from automobile exhaust catalyst smelting tailings according to any one of claims 1 to 8.

9. The thermal insulation material according to claim 8, characterized in that: The rock wool is added with a binder and a waterproofing agent, and solidified to obtain a thermal insulation material.

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