A solid waste-based lightweight roofing prefabricated material and preparation method thereof

Abstract

This invention discloses a solid waste-based lightweight prefabricated roofing material and its preparation method. The solid waste-based lightweight prefabricated roofing material comprises the following components, by weight: 30-60 parts solid waste-based sulphoaluminate cement, 40-70 parts semi-hydrated desulfurized gypsum, 0.2-0.4 parts retarder, 0.02-0.2 parts water reducer, 0-0.2 parts gypsum retarder, and 5-15 parts prefabricated foam; the water-cement ratio is 0.2-0.4. The synergistic effect of the solid waste-based sulphoaluminate cement and the semi-hydrated gypsum significantly improves mechanical properties in the short term, meeting lightweighting requirements. Furthermore, its early strength and rapid hardening properties enable rapid prototyping and demolding.

Description

Technical Field

[0001] The present invention belongs to the technical field of building thermal insulation materials and photovoltaic roofing, and particularly relates to a solid waste-based lightweight roofing prefabricated material and a preparation method thereof. Background Art

[0002] The statements herein merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] Currently, building roofs generally use cement as the main cementitious material, and are prepared and molded by adding lightweight mineral admixtures such as kaolin and fly ash, as well as external admixtures and modifiers, while also introducing gas. Parameters of photovoltaic building roofing materials mainly focus on density, compressive strength, thermal conductivity, and water resistance. However, under conventional preparation processes, photovoltaic building roofing materials have problems such as high density, low compressive strength, low thermal resistance and high thermal conductivity, and long demolding and curing cycles. The use of lightweight materials and the introduction of gas makes it difficult to meet the mechanical strength requirements, and demolding usually requires 1-2 days, and curing for 28 days or more to meet factory requirements. In addition, the strength of the material will also be affected when low density is achieved through foaming, and low density will inevitably lead to low compressive strength. Therefore, to achieve better lightweight insulation effects for photovoltaic building roofs, it is necessary to do so without sacrificing mechanical strength.

[0004] Photovoltaic roofs benefit from high thermal resistance, low thermal conductivity, high compressive strength, and low density. While low density is achieved when these roofs are prepared using a variety of lightweight mineral admixtures and the introduction of gases, mechanical strength is reduced and setting times are long, making rapid demolding difficult. Furthermore, maintenance procedures are complex and demanding. Consequently, existing technologies cannot achieve the rapid demolding, on-site prefabrication, low thermal conductivity, lightweight, and high compressive strength requirements of photovoltaic roofs. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the object of the present invention is to provide a solid waste-based lightweight roofing prefabricated material and a preparation method thereof.

[0006] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0007] In a first aspect, the present invention provides a solid waste-based lightweight roofing prefabricated material, which is composed of the following components, by mass: 30-60 parts of solid waste-based sulphoaluminate cement, 40-70 parts of semi-hydrated desulfurized gypsum, 0.2-0.4 parts of retarder, 0.02-0.2 parts of water reducer, 0-0.2 parts of gypsum retarder, and 5-15 parts of prefabricated foam; the water-cement ratio is 0.2-0.4.

[0008] The solid waste-based sulphoaluminate cement of the present invention is produced by using solid waste as raw material, aiming to improve the utilization rate of solid waste.

[0009] Semi-hydrated desulfurized gypsum sets quickly in the early stage and has stable performance, which is conducive to rapid demoulding in the later stage.

[0010] The present invention uses a large amount of hemihydrate gypsum, and the gypsum sets quickly in the early stage, so the use of a targeted gypsum retarder is more effective; the addition of the retarder has a retarding effect on other components.

[0011] In some embodiments, the solid waste-based lightweight roofing prefabricated material is composed of the following components, by mass: 30-50 parts of solid waste-based sulphoaluminate cement, 40-70 parts of semi-hydrated desulfurized gypsum, 0.2-0.4 parts of retarder, 0.1-0.2 parts of water reducer, 0.1-0.2 parts of gypsum retarder, and 5-15 parts of prefabricated foam; the water-cement ratio is 0.2-0.4.

[0012] In some embodiments, the prefabricated foam is prepared from a protein foaming agent and water in a mass ratio of 1:20-40.

[0013] Protein foaming agents are made primarily from animal keratin (e.g., cattle and sheep) with a certain amount of sodium hydroxide, magnesium chloride, hydrochloric acid, and other chemical raw materials. They are then dissolved by heating, diluted, filtered, and then dehydrated at high temperatures. They are typically dark brown, viscous liquids with advantages such as high foaming multiples, high strength, good stability, and low cost.

[0014] In some embodiments, the retarder is boric acid or tartaric acid.

[0015] In some embodiments, the gypsum retarder is an amino acid gypsum retarder.

[0016] In some embodiments, the water reducer is a polycarboxylate water reducer or a naphthalene water reducer.

[0017] In some embodiments, the solid waste-based lightweight roofing prefabricated material further includes a foam stabilizer, which is calcium stearate, and the mass fraction of the foam stabilizer is 0.2-0.6 parts.

[0018] In a second aspect, the present invention provides a method for preparing the solid waste-based lightweight roofing prefabricated material, comprising the following steps:

[0019] The solid waste-based sulphoaluminate cement, hemihydrate gypsum, retarder, water reducer and gypsum retarder are mixed in proportion to prepare a composite material;

[0020] Mix water and compound materials according to the water-cement ratio to obtain slurry;

[0021] Prepare prefabricated foam by mixing a protein foaming agent with water at a ratio of 1:20-40;

[0022] The prepared prefabricated foam is mixed with slurry in proportion, and the mixture is poured, formed, demoulded and cured to obtain the lightweight prefabricated roofing material.

[0023] In some embodiments, the forming is natural forming, and the forming time is 4-6 hours.

[0024] In some embodiments, the curing time is 20-30 days.

[0025] The beneficial effects achieved by one or more embodiments of the present invention are as follows:

[0026] The synergistic effect of solid waste-based sulphoaluminate cement and hemihydrate gypsum significantly improves mechanical properties in the short term, meeting lightweighting requirements. Its early strength and rapid hardening properties enable rapid prototyping and demolding (4-6 hours). Physical foaming significantly reduces density while still meeting standard strength limits, while also creating a high thermal resistance and enhancing thermal insulation. This effectively meets the requirements for rapid demolding, on-site prefabrication, low thermal conductivity, lightweight construction, and high compressive strength for photovoltaic building roofs. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0028] Figure 1 It is a process flow chart of an embodiment of the present invention. DETAILED DESCRIPTION

[0029] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those skilled in the art to which the present invention belongs.

[0030] The present invention will be further described below with reference to the embodiments.

[0031] Example 1

[0032] A prefabricated material for a lightweight photovoltaic roof consists of the following components, measured by mass: 40 parts of solid waste-based sulphoaluminate cement, 60 parts of semi-hydrated desulfurized gypsum, 0.2 parts of a retarder, 0.04 parts of a water reducer, 0.2 parts of a gypsum retarder, 0.4 parts of a foam stabilizer, and 10 parts of prefabricated foam.

[0033] The water reducer is a polycarboxylate water reducer, the foam stabilizer is calcium stearate, and the water meets the requirements for concrete mixing water.

[0034] A method for preparing prefabricated materials for photovoltaic lightweight roofing comprises the following steps:

[0035] (1) 40 parts of solid waste-based sulphoaluminate cement and 60 parts of hemihydrate gypsum are fully premixed and set aside;

[0036] (2) adding 0.2 parts of retarder, 0.04 parts of water reducer and 0.2 parts of gypsum retarder to the raw materials prepared in step (1), stirring and mixing for 2 minutes to prepare a composite material for standby use;

[0037] (3) Take 20 parts of tap water and pour it into the premix prepared in step (2) at one time, and stir rapidly for 180 seconds;

[0038] (4) preparing fresh prefabricated foam using a physical foaming agent in a ratio of 1:40 between the mass ratio of protein foaming agent and water;

[0039] (5) The prefabricated foam prepared in step (4) is mixed with the slurry prepared in step (3), stirred and mixed, and then the mixed slurry is poured into a mold, naturally formed for 6 hours, demolded (demolding can be completely achieved within 6 hours), and cured for 28 days under standard curing conditions (temperature of 20°C ± 2°C, humidity of 95% standard curing) to obtain a lightweight photovoltaic roof prefabricated material.

[0040] Comparative Example 1

[0041] Material composition: 32 parts of desulfurization gypsum, 16 parts of red mud, 24 parts of aluminum ash, and 28 parts of calcium carbide slag.

[0042] Preparation method: Physical foaming of air and mixing with slurry to prepare foamed concrete.

[0043] The complete demoulding time is 24h.

[0044] Comparative Example 2

[0045] The semi-hydrated gypsum in Example 1 was replaced with desulfurized gypsum. Other conditions were the same as those in Example 1. Complete demoulding could be achieved in 12 hours.

[0046] Comparative Example 3

[0047] The semi-hydrated gypsum in Example 1 was replaced with solid waste-based sulphoaluminate cement. Other aspects were the same as in Example 1, and complete demoulding could be achieved in 8 hours.

[0048] Comparative Example 4

[0049] The solid waste-based sulphoaluminate cement in Example 1 was replaced with silicate cement. Other conditions were the same as in Example 1, and complete demoulding could be achieved within 24 hours.

[0050] Table 1 Relevant properties of photovoltaic lightweight roofing materials of Example 1 and Comparative Example

[0051]

[0052]

[0053] Example 2

[0054] A prefabricated material for a lightweight photovoltaic roof consists of the following components, measured by mass: 40 parts of solid waste-based sulphoaluminate cement, 60 parts of semi-hydrated desulfurized gypsum, 0.2 parts of a retarder, 0.04 parts of a water reducer, 0.2 parts of a gypsum retarder, 0.6 parts of a foam stabilizer, and 15 parts of prefabricated foam.

[0055] The water reducer is a polycarboxylate water reducer, the foam stabilizer is calcium stearate, and the water meets the requirements for concrete mixing water.

[0056] A prefabricated material for a lightweight photovoltaic roof and a preparation method thereof, the method comprising the following steps:

[0057] (1) 40 parts of solid waste-based sulphoaluminate cement and 60 parts of hemihydrate gypsum are fully premixed and set aside;

[0058] (2) adding 0.2 parts of retarder, 0.04 parts of water reducer and 0.2 parts of gypsum retarder to the raw materials prepared in step (1), stirring and mixing for 2 minutes to prepare a composite material for standby use;

[0059] (3) Take 20 parts of tap water and pour it into the premix prepared in step (2) at one time, and stir rapidly for 120 seconds;

[0060] (4) preparing fresh prefabricated foam using a physical foaming agent in a ratio of 1:30 between a protein foaming agent and water;

[0061] (5) The prefabricated foam prepared in step (4) is mixed with the slurry prepared in step (3), stirred and mixed, and then the mixed slurry is poured into a mold, naturally formed for 4 hours, demolded (complete demolding can be achieved in 4 hours), and cured under standard curing conditions for 28 days to obtain a lightweight photovoltaic roof prefabricated material.

[0062] Table 2 Performance data of photovoltaic lightweight roofing materials in Example 2

[0063]

[0064] Example 3

[0065] A prefabricated material for a lightweight photovoltaic roof consists of the following components, measured by mass: 30 parts of solid waste-based sulphoaluminate cement, 60 parts of semi-hydrated desulfurized gypsum, 0.2 parts of a retarder, 0.04 parts of a water reducer, 0.2 parts of a gypsum retarder, 0.3 parts of a foam stabilizer, and 5 parts of prefabricated foam.

[0066] The water reducer is a polycarboxylate water reducer, the foam stabilizer is calcium stearate, the foam stabilizer is hydroxypropyl methylcellulose ether, and the water meets the requirements for concrete mixing water.

[0067] A prefabricated material for a lightweight photovoltaic roof and a preparation method thereof, the method comprising the following steps:

[0068] (1) 30 parts of solid waste-based sulphoaluminate cement and 70 parts of hemihydrate gypsum are fully premixed and stirred for later use;

[0069] (2) The raw materials prepared in (1) are further mixed with 0.2 parts of retarder, 0.04 parts of water reducer, and 0.2 parts of gypsum retarder, and stirred for 2 minutes to prepare a composite material for use;

[0070] (3) Take 30 parts of tap water, pour it into the compound material of step (2) at one time, and stir rapidly for 160 seconds;

[0071] (4) preparing fresh prefabricated foam using a physical foaming agent in a ratio of 1:30 between a protein foaming agent and water;

[0072] (5) The prefabricated foam prepared in step (4) is mixed with the slurry prepared in step (3), and after stirring evenly, the mixed slurry is poured into a mold, naturally formed for 5 hours, demolded, and cured under standard curing conditions for 28 days to obtain a lightweight photovoltaic roof prefabricated material.

[0073] Table 3 Performance comparison of photovoltaic lightweight roofing materials in Example 3

[0074]

[0075] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A solid waste-based lightweight roofing prefabricated material, characterized by: The invention is composed of the following components in parts by mass: 30-40 parts of solid waste-based sulfoaluminate cement, 60 parts of semi-hydrated desulfurized gypsum, 0.2-0.4 parts of retarder, 0.02-0.2 parts of water reducer, 0.2 parts of gypsum retarder, 5-15 parts of prefabricated foam, 0.2-0.6 parts of foam stabilizer; and a water-cement ratio of 0.2-0.4, wherein the water-cement ratio is the ratio of water to the sum of the mass of solid waste-based sulfoaluminate cement and semi-hydrated desulfurized gypsum. The method for preparing the solid waste-based lightweight roofing prefabricated material comprises the following steps: The solid waste-based sulphoaluminate cement, semi-hydrated desulfurized gypsum, retarder, water reducer and gypsum retarder are mixed in proportion to prepare a composite material; Mix water and compound materials according to the water-cement ratio to obtain slurry; Prepare prefabricated foam by mixing a protein foaming agent with water at a ratio of 1:20-40; The prepared prefabricated foam is mixed with the slurry in proportion, and the mixture is poured, formed, demoulded, and cured to obtain a lightweight prefabricated roofing material; The forming is natural forming, and the forming time is 4-6 hours; The retarder is boric acid or tartaric acid; the foam stabilizer is calcium stearate; The gypsum retarder is an amino acid gypsum retarder.

2. The solid waste-based lightweight roofing prefabricated material according to claim 1, characterized in that: The invention is composed of the following components by mass: 30 parts of solid waste-based sulphoaluminate cement, 60 parts of semi-hydrated desulfurized gypsum, 0.2-0.4 parts of retarder, 0.1-0.2 parts of water reducer, 0.2 parts of gypsum retarder, 5-15 parts of prefabricated foam, 0.2-0.6 parts of foam stabilizer, and a water-cement ratio of 0.2-0.

4.

3. The solid waste-based lightweight roofing prefabricated material according to claim 1, characterized in that: The water reducer is a polycarboxylic acid water reducer or a naphthalene water reducer.

4. The solid waste-based lightweight roofing prefabricated material according to claim 1, characterized in that: The curing time is 20-30 days.

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