Large-doping-amount lithium slag light thermal insulation building material and preparation method thereof

Abstract

The invention provides a large-volume lithium slag light thermal insulation building material and a preparation method thereof, and relates to the technical field of waste resource utilization. The large-volume lithium slag light thermal insulation building material provided by the invention is prepared from the following preparation raw materials in parts by mass: 20 to 70 parts of cement, 20 to 70 parts of lithium slag, 15 to 20 parts of water, 0.01 to 0.2 part of a water reducing agent and 6 to 16 parts of a nano foaming agent. Through formula design, the lithium slag is developed into a light thermal insulation material with excellent performance, and the light thermal insulation material has light weight, high strength and good thermal insulation performance. According to the invention, resource recycling is realized, high-value utilization of the lithium slag is realized, the production cost is reduced, and the performance and market competitiveness of the product are improved; the environmental burden of industrial waste residues can be effectively reduced, and the method conforms to the green, low-carbon and environment-friendly development trend.

Description

Technical Field

[0001] The invention relates to the technical field of waste resource utilization, and in particular to a lightweight thermal insulation building material with a large amount of lithium slag and a preparation method thereof. Background Art

[0002] In the current construction industry and industrial production, the demand for environmentally friendly, energy-saving and lightweight insulation materials is growing. Traditional building materials often have problems such as high energy consumption, poor insulation performance, and are not conducive to environmental protection.

[0003] Lithium slag is a byproduct of the lithium extraction process from spodumene. Due to the widespread application of lithium resources and the increase in lithium mining, the treatment and resource utilization of lithium slag has become an important environmental and economic issue. At present, the main treatment method for lithium slag is landfill. The landfill treatment technology is mature and the cost is relatively low, and a large amount of lithium slag can be treated. However, the harmful substances in the lithium slag may penetrate into the groundwater and cause pollution; and the landfill treatment does not realize the resource utilization of lithium slag, wasting the useful components in it. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a lightweight thermal insulation building material with a large amount of lithium slag and a preparation method thereof. The present invention develops lithium slag into a lightweight thermal insulation material with excellent performance, which has light weight, high strength, and good thermal insulation performance, realizes the large-scale disposal and high-value utilization of lithium slag, and effectively reduces the environmental burden of industrial waste slag.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a light-weight thermal insulation building material with a large amount of lithium slag, comprising the following raw materials in parts by weight:

[0007] 20-70 parts of cement, 20-70 parts of lithium slag, 15-20 parts of water, 0.01-0.2 parts of water reducing agent, 6-16 parts of nano foaming agent;

[0008] The nano foaming agent comprises the following components in percentage by weight: 0.1-1.5% of fatty alcohol polyoxyethylene ether surfactant, 0.1-3% of nano montmorillonite, 0.05-3% of cellulose reinforcing agent and the balance of water.

[0009] Preferably, the cement is PO 42.5 cement.

[0010] Preferably, the particle size of the lithium slag is 160-200 mesh.

[0011] Preferably, the particle size of the nano-montmorillonite is 40 to 100 nm.

[0012] Preferably, the light-weight thermal insulation building material with a large amount of lithium slag comprises building blocks or thermal insulation wall panels.

[0013] The present invention provides a method for preparing a lightweight thermal insulation building material with a large amount of lithium slag as described in the above technical solution, comprising the following steps:

[0014] Mechanically foaming the nano foaming agent to obtain prefabricated foam;

[0015] Mixing the cement, lithium slag, water and a water reducing agent to obtain a mixture;

[0016] mixing the mixed material with prefabricated foam to obtain concrete foam;

[0017] The concrete foam is molded and cured in sequence to obtain the light-weight thermal insulation building material with a large amount of lithium slag.

[0018] Preferably, the air pressure of the mechanical foaming is 0.3-3 MPa, and the density of the prefabricated foam is 35-70 g / L.

[0019] Preferably, the mixing of the mixed material and the prefabricated foam is carried out under stirring, and the stirring rate is 10 r / min.

[0020] Preferably, the mold forming includes mold installation and pre-curing, and the mold is removed after the pre-curing; the pre-curing is natural curing, and the time of the natural curing is 0.5 to 2 days.

[0021] Preferably, the curing is standard curing, and the time of the standard curing is 25 to 28 days.

[0022] The present invention provides a lightweight thermal insulation building material with a large amount of lithium slag, comprising the following raw materials by weight: 20 to 70 parts of cement, 20 to 70 parts of lithium slag, 15 to 20 parts of water, 0.01 to 0.2 parts of water reducer, and 6 to 16 parts of nano foaming agent. In the present invention, the lithium slag is rich in active ingredients such as silicon dioxide and aluminum oxide, and has potential value as a lightweight thermal insulation material. Cement can form a strong form of thermal insulation building materials, and the nano foaming agent can make the thermal insulation building materials have good thermal insulation, sound insulation and fire resistance, and improve the strength of the material, so that the material has high quality. The present invention develops lithium slag into a lightweight thermal insulation material with excellent performance through formula design. It has light weight, high strength, and good thermal insulation performance, meets the needs of modern buildings for high-efficiency energy-saving materials, and provides a new solution for promoting the sustainable development of the construction industry. The present invention not only realizes the recycling and reuse of resources, consumes a large amount of lithium slag and makes high-value use of it, thereby reducing production costs, but also effectively reduces the environmental burden of industrial waste slag, reduces energy consumption and carbon dioxide emissions, and conforms to the development trend of green, low-carbon and environmental protection.

[0023] The present invention provides a method for preparing a lightweight thermal insulation building material with a large amount of lithium slag as described in the above technical solution. The preparation process of the present invention is simple, the technology is mature, the production efficiency is high, and the lithium slag thermal insulation building material can be produced on a large scale.

[0024] The results of the examples show that the lightweight thermal insulation building material with a large amount of lithium slag provided by the present invention has a 28d strength of 3.7-7.2 MPa and a density of 790-1330 kg / m 3 , the thermal conductivity is 0.18~0.39W / (m·K). BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The present invention is a schematic diagram of the process of preparing lithium slag lightweight thermal insulation building materials according to an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The present invention provides a light-weight thermal insulation building material with a large amount of lithium slag, comprising the following raw materials in parts by weight:

[0027] 20-70 parts of cement, 20-70 parts of lithium slag, 15-20 parts of water, 0.01-0.2 parts of water reducing agent, 6-16 parts of nano foaming agent;

[0028] The nano foaming agent comprises the following components in percentage by weight: 0.1-1.5% of fatty alcohol polyoxyethylene ether surfactant, 0.1-3% of nano montmorillonite, 0.05-3% of cellulose reinforcing agent and the balance of water.

[0029] In the present invention, unless otherwise specified, all preparation raw materials / components are commercially available products well known to those skilled in the art.

[0030] The high-doped lithium slag lightweight thermal insulation building material provided by the present invention comprises 20 to 70 parts of cement by weight, which may be 20, 30, 40, 50, 60 or 70 parts. In the present invention, the cement is preferably PO 42.5 cement.

[0031] Based on the mass fraction of the cement, the light-weight thermal insulation building material with a large amount of lithium slag provided by the present invention includes 20 to 70 parts of lithium slag, which can be 20, 30, 40, 50, 60 or 70 parts. The present invention has no special requirements on the source of the lithium slag, and lithium slag of sources familiar to those skilled in the art can be used. In the present invention, the mass content of lithium (Li) in the lithium slag is 0.1 to 1%, and it also contains 30 to 50 wt% of silicon (SiO2), 10 to 25 wt% of aluminum (Al2O3), 1 to 10 wt% of sodium (Na2O), 1 to 5 wt% of potassium (K2O), and 1 to 5 wt% of magnesium (MgO). The lithium content in the lithium slag is relatively low, depending on the type of lithium ore and the extraction effect; the silicon content in the lithium slag is usually high, mainly derived from silicate minerals in the ore; the aluminum in the lithium slag is commonly found in aluminosilicate minerals; the sodium content in the lithium slag depends on the ore and the extraction process; the potassium in the lithium slag is in the lithium ore containing potassium minerals; and the magnesium comes from paragenetic minerals. In the present invention, the particle size of the lithium slag is preferably 160-200 meshes.

[0032] Based on the mass fraction of the cement, the lightweight thermal insulation building material with a large amount of lithium slag provided by the present invention includes 15 to 20 parts of water, which can be 15, 16, 17, 18, 19 or 20 parts.

[0033] Based on the mass fraction of the cement, the high-doped lithium slag lightweight thermal insulation building material provided by the present invention includes 0.01 to 0.2 parts of a water reducer, which may be 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.1 or 0.2 parts. In the present invention, the water reducer is preferably a polycarboxylate water reducer.

[0034] Based on the mass fraction of the cement, the lightweight thermal insulation building material with a large amount of lithium slag provided by the present invention includes 6 to 16 parts of nano foaming agent, which can be 6, 10, 15 or 16 parts. In the present invention, the nano foaming agent includes the following components in mass percentage: 0.1 to 1.5% of fatty alcohol polyoxyethylene ether surfactant, 0.1 to 3% of nano montmorillonite, 0.05 to 3% of cellulose reinforcing agent, and the balance of water. In the present invention, the mass percentage of fatty alcohol polyoxyethylene ether surfactant in the nano foaming agent is preferably 1 to 1.5%, more preferably 1.1 to 1.4%; the fatty alcohol polyoxyethylene ether surfactant is preferably fatty alcohol polyoxyethylene ether sulfate. In the present invention, the mass percentage of nano montmorillonite in the nano foaming agent is preferably 1.5 to 3%, more preferably 2.5 to 3%; the particle size of the nano montmorillonite is preferably 40 to 100 nm, more preferably 50 to 80 nm. In the present invention, the mass percentage of the cellulose-based reinforcing agent in the nano-foaming agent is preferably 1.5-3%, more preferably 2-2.5%; the cellulose-based reinforcing agent preferably includes cellulose and / or cellulose derivatives, the cellulose derivatives preferably include hydroxyethyl methyl cellulose, the relative molecular weight of the cellulose is preferably 50,000-300,000, more preferably 100,000-200,000, the relative molecular weight of the hydroxyethyl methyl cellulose is preferably 50,000-300,000, more preferably 100,000-200,000.

[0035] The present invention has no special requirements for the preparation method of the nano foaming agent, and the components can be mixed evenly. In the embodiment of the present invention, the fatty alcohol polyoxyethylene ether surfactant, nano montmorillonite and cellulose reinforcing agent are also called foaming powder, and the nano foaming agent is also called foaming liquid.

[0036] The nano foaming agent used in the present invention has strong stability, is not easy to break after foaming, and can still prevent foam collapse under high salt content. The density of lithium slag is relatively large. The present invention strictly controls the concentration and dosage of the nano foaming agent to eliminate the defoaming effect of lithium slag on the foaming agent. The sodium salt remaining in the lithium slag migrates to the surface of the concrete product along with the water. When the water evaporates, salt crystals are generated on the surface of the product to form frosting, which affects the appearance of the material and may expand in the near-surface area of ​​the material, causing surface damage. The high molecular polymer in the nano foaming agent used in the present invention can reduce frosting and improve the strength and durability of the product.

[0037] In the present invention, the high-doped lithium slag lightweight thermal insulation building material preferably includes blocks or thermal insulation wallboards. The lithium slag lightweight blocks or thermal insulation wallboards are light and have excellent thermal insulation properties, can be used in the field of building partition walls / thermal insulation, and also have the characteristics of environmental protection and sustainable development, which can improve the market competitiveness of the product.

[0038] The present invention provides a method for preparing a lightweight thermal insulation building material with a large amount of lithium slag as described in the above technical solution, comprising the following steps:

[0039] Mechanically foaming the nano foaming agent to obtain prefabricated foam;

[0040] Mixing the cement, lithium slag, water and a water reducing agent to obtain a mixture;

[0041] mixing the mixed material with prefabricated foam to obtain concrete foam;

[0042] The concrete foam is molded and cured in sequence to obtain the light-weight thermal insulation building material with a large amount of lithium slag.

[0043] Figure 1 This is a schematic diagram of the process of preparing lithium slag lightweight thermal insulation building materials according to an embodiment of the present invention. Figure 1 Provide detailed explanation.

[0044] The present invention performs mechanical foaming (i.e., physical foaming) on ​​the nano foaming agent to obtain prefabricated foam. In the present invention, the mechanical foaming is preferably performed by a foaming machine; the air pressure of the mechanical foaming is preferably 0.3-3 MPa, and the density of the prefabricated foam is preferably 35-70 g / L.

[0045] The present invention mixes the cement, lithium slag, water and a water reducing agent to obtain a mixture. Before use, the present invention preferably detects whether the heavy metal content of the lithium slag exceeds the standard, and uses the lithium slag whose heavy metal content meets the national standard for preparing lightweight thermal insulation building materials.

[0046] In the present invention, the specific operation of mixing the cement, lithium slag, water and water reducing agent is preferably: adding water to the mixer, then adding the water reducing agent for the first stirring and mixing, and then adding cement and lithium slag for the second stirring and mixing. In the present invention, the speed of the first stirring and mixing is preferably 20r / min, and the stirring time is preferably 2min; the speed of the second stirring and mixing is preferably 50r / min, and the clockwise and counterclockwise stirring are respectively 2 to 5min. After the cement, lithium slag, water and water reducing agent are mixed, a uniform slurry is obtained, that is, the mixture.

[0047] After obtaining the mixture and the prefabricated foam, the present invention mixes the mixture and the prefabricated foam to obtain concrete foam. In the present invention, the mixing of the mixture and the prefabricated foam is preferably carried out under stirring, and the stirring rate is preferably 10r / min; the specific operation of mixing the mixture and the prefabricated foam is preferably: reducing the speed of the mixer containing the mixture to 10r / min, injecting the prefabricated foam into the mixture, stirring clockwise and counterclockwise for 1 to 2 minutes respectively, so that a uniform foam structure is formed in the concrete, that is, the concrete foam is obtained.

[0048] After obtaining the concrete foam, the present invention sequentially performs mold forming and curing curing on the concrete foam to obtain the light-weight thermal insulation building material with a large amount of lithium slag. In the present invention, the mold forming preferably includes mold filling (i.e., pouring the concrete foam into a pre-prepared mold) and pre-curing, and the mold filling can also be vibrated, and the mold is removed after the pre-curing; the pre-curing is preferably natural curing, and the time of the natural curing is preferably 0.5 to 2 days. In the present invention, the curing curing is preferably standard curing (i.e., standard curing), and the time of the standard curing is preferably 25 to 28 days. The present invention ensures that the material obtains sufficient strength and stability during the hardening process through the curing curing. In the present invention, when preparing blocks, the time of natural curing is more preferably 12 hours, and after natural curing, wire cutting is performed to the desired size, and then standard curing is performed, and the time of standard curing is more preferably 27.5 days; when preparing thermal insulation wallboards, the time of natural curing is more preferably 1 day, and the time of standard curing is more preferably 27 days.

[0049] The process flow of preparing lightweight thermal insulation building materials using lithium slag is simple and efficient, and large-scale production can be quickly realized. The thermal insulation building materials prepared by using foamed concrete have low density, excellent thermal insulation performance and good compressive strength, and are lighter, more environmentally friendly and more energy-efficient than traditional thermal insulation materials. In addition, the foam structure of foamed concrete enables the wall panels to have better thermal insulation performance, which can effectively reduce the energy consumption of the building and improve the energy utilization rate of the building.

[0050] In order to further illustrate the present invention, the lightweight thermal insulation building material with a large amount of lithium slag and the preparation method thereof provided by the present invention are described in detail below in conjunction with examples, but they should not be understood as limiting the scope of protection of the present invention.

[0051] The preparation process of the nano foaming agent used in the following examples is as follows:

[0052] The surfactant sodium polyoxyethylene fatty alcohol ether sulfate (AES) is dissolved in water and stirred with a glass rod until it is dissolved to prepare a surfactant solution with a concentration of 1.5wt% (solution 1); nano-montmorillonite (particle size 50-80nm) is dispersed in solution 1 and stirred with a glass rod until it is evenly dispersed, and the mass ratio of the nano-montmorillonite to the surfactant is 2:1 (solution 2); hydroxyethyl methylcellulose (relative molecular weight 100000) is added to solution 2, wherein the amount of hydroxyethyl methylcellulose is 90wt% of the nano-montmorillonite, and stirred with a glass rod until it is evenly dispersed, and the stirring speed is 20r / min to obtain a nano foaming agent.

[0053] Example 1

[0054] A light-weight building block / insulating wallboard with a large amount of lithium slag is prepared from the following materials: 560 kg of P.O42.5 cement, 240 kg of lithium slag (160-200 meshes), 160 kg of water, 560 g of polycarboxylic acid water-reducing agent, and 80 kg of nano foaming agent.

[0055] The preparation steps are as follows (process as Figure 1 shown):

[0056] (1) Weigh the required water and add it into a blender;

[0057] (2) Weigh the required polycarboxylate water reducer and pour it into a mixer at a speed of 20 r / min for 2 min;

[0058] (3) Weigh the required cement and lithium slag, pour them into a mixer, and stir at 50 r / min in clockwise and counterclockwise directions for 2 to 5 min respectively until the slurry is uniform.

[0059] (4) The speed of the mixer was reduced to 10 r / min, and the nano foaming agent was foamed using a foaming machine (the foaming pressure was 0.6 MPa, and the density was 60 g / L), and then injected into the mixer, and stirred clockwise and counterclockwise for 1 to 2 min respectively.

[0060] (5) For foam insulation wall panels, simply inject the mixed slurry into the required mold, naturally cure for 24 hours, remove the mold, and then continue standard curing for 27 days; for lightweight blocks, simply inject the mixed slurry into the required mold, naturally cure for 12 hours, remove the mold, and then perform wire cutting to the required size. After cutting, continue standard curing for 27.5 days.

[0061] The 28d (natural curing + standard curing) strength of lithium slag lightweight blocks / insulation wall panels is 4.8-5.2MPa, and the density is 790-810kg / m 3 , the thermal conductivity is 0.18~0.21W / (m·K).

[0062] Example 2

[0063] A light-weight building block / insulating wallboard with a large amount of lithium slag is prepared from the following materials: 320 kg of P.O42.5 cement, 480 kg of lithium slag (160-200 meshes), 160 kg of water, 320 g of polycarboxylic acid water-reducing agent, and 80 kg of nano foaming agent.

[0064] The preparation steps are the same as those in Example 1.

[0065] The 28d strength of lithium slag lightweight blocks / insulation wall panels is 3.7-5.1MPa, and the density is 990-1080kg / m 3 , the thermal conductivity is 0.26~0.27W / (m·K).

[0066] Example 3

[0067] A light-weight building block / insulating wallboard with a large amount of lithium slag is prepared from the following materials: 240 kg of P.O42.5 cement, 560 kg of lithium slag (160-200 meshes), 160 kg of water, 240 g of polycarboxylic acid water-reducing agent, and 80 kg of nano foaming agent.

[0068] The preparation steps are the same as those in Example 1.

[0069] The 28d strength of lithium slag lightweight blocks / insulation wall panels is 5.5-7.2MPa, and the density is 1250-1330kg / m 3 , the thermal conductivity is 0.37~0.39W / (m·K).

[0070] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A lightweight thermal insulation building material with a large amount of lithium slag, characterized in that: The preparation comprises the following raw materials in parts by weight: 20-70 parts of cement, 20-70 parts of lithium slag, 15-20 parts of water, 0.01-0.2 parts of water reducing agent, 6-16 parts of nano foaming agent; The nano foaming agent comprises the following components in percentage by weight: 0.1-1.5% of fatty alcohol polyoxyethylene ether surfactant, 0.1-3% of nano montmorillonite, 0.05-3% of cellulose reinforcing agent and the balance of water.

2. The light-weight thermal insulation building material with high lithium content according to claim 1, characterized in that: The cement is P.O42.5 cement.

3. The light-weight thermal insulation building material with high lithium content according to claim 1, characterized in that: The particle size of the lithium slag is 160-200 meshes.

4. The light-weight thermal insulation building material with a large amount of lithium slag according to claim 1, characterized in that: The particle size of the nano-montmorillonite is 40-100 nm.

5. The light-weight thermal insulation building material with a large amount of lithium slag according to claim 1, characterized in that: The light-weight heat-insulating building material with a large amount of lithium slag comprises building blocks or heat-insulating wall panels.

6. The method for preparing the lightweight thermal insulation building material with a large amount of lithium slag as claimed in any one of claims 1 to 5, characterized in that: The following steps are involved: Mechanically foaming the nano foaming agent to obtain prefabricated foam; Mixing the cement, lithium slag, water and a water reducing agent to obtain a mixture; mixing the mixed material with prefabricated foam to obtain concrete foam; The concrete foam is molded and cured in sequence to obtain the light-weight thermal insulation building material with a large amount of lithium slag.

7. The preparation method according to claim 6, characterized in that: The air pressure of the mechanical foaming is 0.3-3 MPa, and the density of the prefabricated foam is 35-70 g / L.

8. The preparation method according to claim 6, characterized in that: The mixing of the mixed material and the prefabricated foam is carried out under stirring, and the stirring rate is 10 r / min.

9. The preparation method according to claim 6, characterized in that: The mold forming includes mold installation and pre-curing, and the mold is removed after the pre-curing; the pre-curing is natural curing, and the time of the natural curing is 0.5 to 2 days.

10. The preparation method according to claim 6, characterized in that: The curing process is standard curing, and the time of the standard curing is 25 to 28 days.

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