Waste aerogel recovery thermal insulation mortar and preparation method thereof

Abstract

The invention relates to waste aerogel recycled thermal insulation mortar and a preparation method thereof. The preparation method of the waste aerogel recovery thermal insulation mortar comprises the following steps: mixing cement, silica fume and waste hydrophobic aerogel powder into a dry material, adding water into the dry material, and stirring to obtain a master batch; mixing rubber powder, glass beads, glass fiber aerogel felt leftover materials, cement and water to form cement slurry; and adding the cement slurry into the master batch, stirring, then adding the water reducing agent, and stirring. The waste aerogel powder is adopted, so that the cost of the aerogel thermal insulation mortar can be effectively reduced, and the problems of environmental pollution and high treatment cost of waste aerogel treatment can be solved. Meanwhile, the glass fiber aerogel felt leftover materials in the waste aerogel can improve the crack resistance of the thermal insulation mortar.

Description

Technical Field

[0001] The invention belongs to the technical field of thermal insulation materials, and particularly relates to a waste aerogel recycling thermal insulation mortar and a preparation method thereof. Background Art

[0002] Waste aerogel refers to waste that has no utilization value and needs to be treated during the aerogel industrial production process. It mainly includes glass fiber aerogel felt scraps and waste hydrophobic aerogel powder. With the rapid development of the aerogel industry, the amount of waste aerogel is also increasing day by day. The treatment of waste aerogel is generally carried out by landfill, but because it is a hydrophobic nanomolecular material, waste aerogel will cause serious pollution to water resources and the price of waste aerogel treatment has become one of the reasons for the high price of aerogel.

[0003] Traditional inorganic insulation mortars are mainly vitrified microsphere insulation mortar and expanded perlite insulation mortar. Vitrified microsphere insulation mortar and expanded perlite insulation mortar have large water absorption and water vapor permeability. After absorbing water, the thermal conductivity increases, the insulation effect is unstable and it is easy to crack, fall off and other defects, affecting the safety and reliability of the building.

[0004] Aerogel is a highly promising building exterior wall insulation material. Aerogel insulation mortar can be used for both internal and external wall insulation, taking into account the advantages of low thermal conductivity of organic boards and the convenient construction of insulation mortar. However, the high price of aerogel has always been the reason why it cannot be used on a large scale in the construction industry. Summary of the invention

[0005] The purpose of the present invention is to provide a waste aerogel recycling thermal insulation mortar to solve the technical problem that the existing aerogel thermal insulation mortar is too expensive to be widely used in the construction industry.

[0006] The second object of the present invention is to provide a method for preparing thermal insulation mortar recycled from waste aerogel.

[0007] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0008] A method for preparing waste aerogel recycling thermal insulation mortar comprises the following steps:

[0009] 1) Mix cement, silica fume and waste hydrophobic aerogel powder into dry material, add water to the dry material and stir to obtain a masterbatch;

[0010] 2) Mixing rubber powder, vitrified microspheres, glass fiber aerogel felt scraps, cement and water to form cement slurry;

[0011] 3) adding the cement slurry in step 2) into the masterbatch in step 1) and stirring, and then adding a water reducing agent and stirring to obtain the product.

[0012] Furthermore, the mass percentage ratios of the cement, silica fume, waste hydrophobic aerogel powder, rubber powder, vitrified microspheres, glass fiber aerogel felt scraps, and water reducing agent are: 46%: 5.5%: 5-21%: 0.58%: 26-48%: 0.18%: 0.54%.

[0014] Furthermore, the glass fiber aerogel felt scraps in step 2) are flocculent glass fiber aerogel felt scraps; the flocculent glass fiber aerogel felt scraps are prepared by separating multiple layers of glass fiber aerogel scraps into single layers of glass fiber aerogel scraps, and then beating the single layers of glass fiber aerogel scraps into flocculent form.

[0015] Furthermore, the mass content of aerogel in the glass fiber aerogel felt scraps is 50-80%.

[0016] Furthermore, the method for detecting the mass content of aerogel in the glass fiber aerogel felt scraps is as follows:

[0017] According to the specifications of the glass fiber felt in the glass fiber aerogel scraps, the mass of the glass fiber felt with a surface area of ​​S is m1, and a sample with a surface area of ​​S is cut out from the glass fiber aerogel felt scraps. The mass of the measured sample is m2. The calculation formula for the mass content of aerogel in the glass fiber aerogel felt scraps is shown in Formula I:

[0018]

[0019] Furthermore, the water reducer is a polycarboxylate water reducer.

[0020] Furthermore, the rubber powder is redispersible latex powder.

[0021] Furthermore, in step 1), 70% of the cement, silica fume and waste hydrophobic aerogel powder are first mixed into dry material, and 70% of water is added to the dry material and stirred to obtain a masterbatch; in step 2), the glue powder, vitrified microspheres, glass fiber aerogel felt scraps, the remaining 30% of water and cement are mixed into cement slurry.

[0022] Furthermore, the mass ratio of cement to water is 100:25.

[0023] A waste aerogel recovery thermal insulation mortar is prepared by adopting the above-mentioned waste aerogel recovery thermal insulation mortar preparation method.

[0024] Beneficial effects of the present invention:

[0025] Hydrophobic aerogel is difficult to dissolve in water. Directly adding waste hydrophobic aerogel powder into water will cause most of the waste hydrophobic aerogel powder to volatilize. Therefore, the present invention adopts the method of wrapping the waste hydrophobic aerogel powder with cement to first prepare dry material, which can effectively prevent the problem of volatilization of the waste hydrophobic aerogel powder and has a good molding effect.

[0026] The present invention uses waste aerogel, which can effectively reduce the cost of aerogel thermal insulation mortar and solve the problem of environmental pollution and high cost of waste aerogel treatment. At the same time, the glass fiber aerogel felt scraps in the waste aerogel can increase the crack resistance of the thermal insulation mortar. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is the thermal conductivity of the waste aerogel recovery insulation mortar in Examples 1-4 and Comparative Example 1;

[0028] Figure 2 The compressive strength of the waste aerogel recovery insulation mortar in Examples 1-4 and Comparative Example 1;

[0029] Figure 3 The gram weight of the thermal insulation mortar recovered from the waste aerogel in Examples 1-4 and Comparative Example 1. DETAILED DESCRIPTION

[0030] The present invention will be further described below in conjunction with the embodiments of the present invention.

[0031] The model of polycarboxylic acid water-reducing agent powder is polycarboxylic acid JQ-1.

[0032] Waste hydrophobic aerogel powder and glass fiber aerogel felt scraps come from the hydrophobic aerogel powder waste and glass fiber aerogel felt scraps generated during the production of lithium batteries. There are two main sources of waste hydrophobic aerogel powder. Method 1: Configure a hydrophobic aerogel pool, soak the glass fiber felt in the hydrophobic aerogel pool to obtain the glass fiber aerogel felt, and then scrape off the excess hydrophobic aerogel powder on the surface of the glass fiber aerogel felt to obtain the waste waste hydrophobic aerogel powder. Method 2: The configured hydrophobic aerogel pool will also be treated as waste if it is not fully used up, thereby obtaining waste waste hydrophobic aerogel powder. There are three main methods for obtaining glass fiber aerogel felt scraps. Method 1: After the whole piece of glass fiber felt is soaked in the hydrophobic aerogel pool, it needs to be cut into a fixed size. A lot of scraps will be generated during the shearing process to obtain glass fiber aerogel felt scraps. Method 2: Glass fiber aerogel felt that fails the quality inspection will also be treated as waste to obtain glass fiber aerogel felt scraps. Method 3: After the glass fiber aerogel felt reaches its service life, it becomes waste and the glass fiber aerogel felt scraps are obtained.

[0033] The mass content of aerogel in the scraps of glass fiber aerogel felt is 50-80%, and the mass content of aerogel in the scraps of glass fiber aerogel felt is measured to be α%. The total mass of hydrophobic aerogel powder required for waste aerogel recycling thermal insulation mortar = the mass of aerogel in the scraps of glass fiber aerogel felt + the mass of waste hydrophobic aerogel powder, and the mass of aerogel in the scraps of glass fiber aerogel felt = the mass of required scraps of glass fiber aerogel felt × α%.

[0034] Method for measuring aerogel in glass fiber aerogel scraps: Understand the specifications of glass fiber felt in glass fiber aerogel scraps. For glass fiber felt of fixed specifications (bare felt not combined with aerogel), the mass m1 of glass fiber felt with fixed size, such as surface area S, is fixed; or select glass fiber felt of corresponding specifications, cut out glass fiber felt with surface area S, and weigh its m1; since the size of glass fiber aerogel felt scraps is relatively large, a large piece of waste glass fiber aerogel felt scraps can be cut out to produce a sample with surface area S, and its mass is measured to be m2, then the aerogel content of glass fiber aerogel felt scraps can be obtained. The calculation formula of the mass content of aerogel in glass fiber aerogel felt scraps is shown in Formula I:

[0035]

[0036] The fixed size refers to regular sizes such as triangles, rectangles or squares. For example, for glass fiber felt of fixed specifications, the weight of a 20cm*20cm glass fiber felt is known and determined, and its weight is m1. For waste glass fiber aerogel felt scraps, a 20cm*20cm piece of waste glass fiber aerogel felt scraps can be cut out and then weighed to obtain its weight m2.

[0037] Example 1

[0038] The method for preparing the waste aerogel recycling thermal insulation mortar of Example 1 comprises the following steps:

[0039] 1) First, 70% of cement, silica fume and waste hydrophobic aerogel powder are mixed into a dry material, 70% of water is added to the dry material to obtain a masterbatch, and then the waste hydrophobic aerogel powder is slowly stirred manually by a stirring rod to prevent volatilization of the waste hydrophobic aerogel powder, and the stirring is stopped after the waste hydrophobic aerogel powder is integrated into the masterbatch and no longer volatilizes;

[0040] 2) Mixing the redispersible latex powder, the vitrified microspheres, the flocculent glass fiber aerogel felt scraps, the remaining 30% of cement and water to form a cement slurry; the content of aerogel in the flocculent glass fiber aerogel felt scraps is 50%;

[0041] 3) Add the cement slurry in step 2) to the masterbatch in step 1) and stir evenly, then add the polycarboxylate water-reducing agent powder and stir to obtain. Based on 1 kg of waste aerogel recycling insulation mortar, the addition amounts of cement, silica fume, waste hydrophobic aerogel powder, redispersible latex powder, vitrified microspheres, flocculent glass fiber aerogel felt scraps, and polycarboxylate water-reducing agent powder are 460 g, 55 g, 157 g, 5.8 g, 315 g, 1.8 g, and 5.4 g, respectively.

[0042] The total amount of water added was 115 g.

[0043] The preparation method of flocculent glass fiber aerogel felt scraps is to separate multi-layer glass fiber aerogel scraps into single-layer glass fiber aerogel scraps, and then break the single-layer glass fiber aerogel scraps into flocculent to obtain flocculent glass fiber aerogel felt scraps.

[0044] Example 2

[0045] The preparation method of the waste aerogel recycling thermal insulation mortar of Example 2 is roughly the same as that of Example 1. The difference between the preparation method of the waste aerogel recycling thermal insulation mortar of Example 2 and Example 1 is that, based on 1 kg of waste aerogel recycling thermal insulation mortar, the addition amounts of cement, silica fume, waste hydrophobic aerogel powder, redispersible latex powder, vitrified microspheres, flocculent glass fiber aerogel felt scraps, and polycarboxylic acid water reducer powder are 460g, 55g, 108g, 5.8g, 364g, 1.8g, and 5.4g, respectively. The aerogel content in the flocculent glass fiber aerogel felt scraps is 60%.

[0046] In Example 2: the mass percentage ratios of the cement, silica fume, waste hydrophobic aerogel powder, rubber powder, vitrified microspheres, glass fiber aerogel felt scraps, and water reducing agent are: 46%: 5.5%: 5.7%: 0.58%: 41.5%: 0.18%: 0.54%.

[0047] Example 3

[0048] The preparation method of the waste aerogel recycling thermal insulation mortar of Example 3 is roughly the same as that of Example 1. The difference between the preparation method of the waste aerogel recycling thermal insulation mortar of Example 3 and Example 1 is that, based on 1 kg of waste aerogel recycling thermal insulation mortar, the addition amounts of cement, silica fume, waste hydrophobic aerogel powder, redispersible latex powder, vitrified microspheres, glass fiber aerogel felt scraps, and polycarboxylic acid water reducer powder are 460g, 55g, 157g, 5.8g, 315g, 1.8g, and 5.4g, respectively. The content of aerogel in the glass fiber aerogel felt scraps is 70%.

[0049] In Example 3: the mass percentage ratios of the cement, silica fume, waste hydrophobic aerogel powder, rubber powder, vitrified microspheres, glass fiber aerogel felt scraps, and water reducing agent are: 46%: 5.5%: 10.8%: 0.58%: 36.4%: 0.18%: 0.54%.

[0050] Example 4

[0051] The preparation method of the waste aerogel recycling thermal insulation mortar of Example 4 is roughly the same as that of Example 1. The difference between the preparation method of the waste aerogel recycling thermal insulation mortar of Example 4 and Example 1 is that, based on 1 kg of waste aerogel recycling thermal insulation mortar, the added masses of cement, silica fume, waste hydrophobic aerogel powder, redispersible latex powder, vitrified microspheres, glass fiber aerogel felt scraps, and polycarboxylic acid water reducer powder are 460g, 55g, 208g, 5.8g, 264g, 1.8g, and 5.4g, respectively. The content of aerogel in the glass fiber aerogel felt scraps is 80%.

[0052] In Example 4, the mass percentage of cement, silica fume, waste hydrophobic aerogel powder, rubber powder, vitrified microspheres, glass fiber aerogel felt scraps, and water reducer is: 46%: 5.5%: 15.7%: 0.58%: 31.5%: 0.18%: 0.54%. Example 4 is the best mix ratio, and its softening coefficient is 0.61.

[0053] Embodiment 5:

[0054] In Example 5, the mass percentage ratios of cement, silica fume, waste hydrophobic aerogel powder, rubber powder, vitrified microspheres, glass fiber aerogel felt scraps, and water reducing agent are: 46%: 5.5%: 20.8%: 0.58%: 26.4%: 0.18%: 0.54%.

[0055] Comparative Example 1

[0056] The preparation method of the thermal insulation mortar of Comparative Example 1 comprises the following steps:

[0057] 1) First, mix 70% of cement and silica fume into dry materials, add 70% of water to the dry materials to obtain a masterbatch, and then stir manually with a stirring rod;

[0058] 2) Mixing the redispersible latex powder, the vitrified microspheres, the flocculent glass fiber aerogel felt scraps, the remaining 30% of cement, and water to form a cement slurry; the aerogel content in the glass fiber aerogel felt scraps is 50%;

[0059] 3) Add the cement slurry in step 2) to the masterbatch in step 1) and stir evenly, then add polycarboxylate water-reducing agent powder and stir to obtain. Based on 1 kg of thermal insulation mortar, the addition amounts of cement, silica fume, redispersible latex powder, vitrified microspheres, glass fiber aerogel felt scraps, and polycarboxylate water-reducing agent powder are 460 g, 55 g, 5.8 g, 472 g, 1.8 g, and 5.4 g, respectively.

[0060] In Comparative Example 1, the mass percentages of the cement, silica fume, waste hydrophobic aerogel powder, rubber powder, vitrified microspheres, glass fiber aerogel felt scraps, and water reducing agent are: 46%: 5.5%: 25.8%: 0.58%: 21.4%: 0.18%: 0.54%.

[0061] The comparison of thermal conductivity, compressive strength, gram weight, tensile bond strength, compressive shear bond strength and water absorption of the thermal insulation mortars of Examples 1-5 and Comparative Example 1 is shown in Table 1.

[0062] Table 1 Thermal conductivity, compressive strength, finished product weight, rope bond strength, compression shear bond strength, water absorption of thermal insulation mortar of Examples 1-5 and Comparative Example 1

[0063]

[0064] In the present invention:

[0065] The relationship between the cumulative sieving rate of vitrified microspheres and aerogels is:

[0066]

[0067] The relationship between the proportion of aerogel in the thermal insulation aggregate mass and the bulk density, apparent density and porosity is:

Claims

1. A method for preparing waste aerogel recycling thermal insulation mortar, characterized in that: The following steps are involved: 1) Mix cement, silica fume and waste hydrophobic aerogel powder into dry material, add water to the dry material and stir to obtain a masterbatch; 2) Mixing rubber powder, vitrified microspheres, glass fiber aerogel felt scraps, cement and water to form cement slurry; 3) adding the cement slurry in step 2) into the masterbatch in step 1) and stirring, and then adding a water reducing agent and stirring to obtain the product.

2. The method for preparing waste aerogel recycling thermal insulation mortar according to claim 1, characterized in that: The mass percentages of the cement, silica fume, waste hydrophobic aerogel powder, rubber powder, vitrified microspheres, glass fiber aerogel felt scraps and water reducing agent are: 46%: 5.5%: 5-21%: 0.58%: 26-48%: 0.18%: 0.54%.

3. The method for preparing waste aerogel recycling thermal insulation mortar according to claim 1, characterized in that: The glass fiber aerogel felt scraps in step 2) are flocculent glass fiber aerogel felt scraps; the flocculent glass fiber aerogel felt scraps are prepared by separating multiple layers of glass fiber aerogel scraps into single layers of glass fiber aerogel scraps, and then beating the single layers of glass fiber aerogel scraps into flocculent form.

4. The method for preparing waste aerogel recycling thermal insulation mortar according to claim 1, characterized in that: The mass content of aerogel in the glass fiber aerogel felt scraps is 50-80%.

5. The method for preparing waste aerogel recycling thermal insulation mortar according to claim 4, characterized in that: The method for detecting the mass content of aerogel in glass fiber aerogel felt scraps is as follows: According to the specifications of the glass fiber felt in the glass fiber aerogel scraps, the mass of the glass fiber felt with a surface area of ​​S is m1, and a sample with a surface area of ​​S is cut out from the glass fiber aerogel felt scraps. The mass of the measured sample is m2. The calculation formula for the mass content of aerogel in the glass fiber aerogel felt scraps is shown in Formula I:

6. The method for preparing waste aerogel recycling thermal insulation mortar according to claim 1, characterized in that: The water reducer is a polycarboxylate water reducer.

7. The method for preparing waste aerogel recycling thermal insulation mortar according to claim 1, characterized in that: The rubber powder is redispersible latex powder.

8. The method for preparing waste aerogel recycling thermal insulation mortar according to claim 1, characterized in that: In step 1), 70% of the cement, silica fume and waste hydrophobic aerogel powder are first mixed into dry material, and 70% of water is added to the dry material and stirred to obtain a masterbatch; in step 2), the rubber powder, vitrified microspheres, glass fiber aerogel felt scraps, the remaining 30% of water and cement are mixed into cement slurry.

9. The method for preparing waste aerogel recycling thermal insulation mortar according to claim 1 or 8, characterized in that: The mass ratio of cement to water is 100:

25.

10. A waste aerogel recycling thermal insulation mortar, characterized in that: The thermal insulation mortar is prepared by the method for preparing the waste aerogel recovery mortar according to any one of claims 1 to 8.

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