Carbon-sequestration light composite self-insulation building block and preparation method thereof

Abstract

The invention belongs to the technical field of building materials, and discloses a carbon-sequestration lightweight composite self-insulation building block which comprises the following components in parts by weight: 300-350 parts of cement, 100-175 parts of quartz sand, 25-50 parts of quick lime, 0.3-0.8 part of aluminum powder paste, 0.7-2 parts of a water reducing agent, 14-22 parts of a catalyst, 10-20 parts of a phase change energy storage material and 170-230 parts of water. The invention also provides a preparation method of the building block, which comprises the following steps: weighing the raw materials, putting the raw materials into a closed stirrer for stirring, introducing CO2 gas into the stirrer, injecting slurry into a self-heat-preservation hollow building block test mold, filling the heat-preservation core material 8-12 hours after pouring, and naturally curing the test block to obtain the carbon-sequestration light composite self-heat-preservation building block. The self-heat-preservation building block has the characteristics of light weight and carbon sequestration on the basis of excellent heat preservation and heat insulation performance and mechanical strength, and meets the requirements of development of the green building industry nowadays.

Description

Technical Field

[0001] The invention belongs to the technical field of building materials, and particularly relates to a carbon-fixing lightweight composite self-insulating building block and a preparation method thereof. Background Art

[0002] With the rise of energy-saving and green building concepts, traditional building materials, while meeting structural requirements, often fail to effectively address thermal insulation, heat insulation, and energy consumption. Therefore, the development of new building materials, especially composite self-insulating building blocks, has become an important means of improving building energy efficiency and reducing energy consumption.

[0003] The core of self-insulating block technology is to reduce heat conduction and improve the thermal insulation performance of walls through hollow structures or specific composite materials. Hollow blocks reduce heat flow through internal pores, effectively reducing energy loss. They provide excellent insulation, especially in building exterior walls. Composite self-insulating blocks combine insulation with masonry materials to produce a composite wall material. While maintaining the structural strength of the wall, these blocks effectively reduce heat loss through internal or external insulation layers, thereby improving the wall's thermal insulation performance and achieving high energy savings. They do not require an additional exterior wall insulation layer, saving material costs and simplifying the construction process. However, traditional self-insulating blocks are formed through compression molding to increase mechanical strength, which increases their density and makes them excessively heavy.

[0004] Carbon sequestration technology involves capturing carbon dioxide from the atmosphere and fixing it in solid materials through various means, thereby reducing greenhouse gas emissions and mitigating global climate change. Incorporating carbon sequestration capabilities into self-insulating building blocks—not only effectively improving a building's insulation performance but also reducing greenhouse gas emissions by absorbing and fixing carbon dioxide—is currently an innovative approach to addressing climate change and promoting the development of green buildings. Summary of the Invention

[0005] The purpose of the present invention is to overcome at least one of the shortcomings of the prior art and provide a carbon-fixing lightweight composite self-insulating building block and a preparation method thereof. The self-insulating building block not only has excellent thermal insulation performance and mechanical strength, but also has the characteristics of lightness and carbon fixation, meeting the needs of the development of the current green building industry.

[0006] The technical solution adopted by the present invention is:

[0007] In one aspect, the present invention provides a carbon-fixing lightweight composite self-insulating building block, which includes, by weight, 300-350 parts of cement, 100-175 parts of quartz sand, 25-50 parts of quicklime, 0.3-0.8 parts of aluminum powder paste, 0.7-2 parts of water reducer, 14-22 parts of catalyst, 10-20 parts of phase change energy storage material, and 170-230 parts of water.

[0008] The present invention adopts the above-mentioned raw material ratio, which can make the self-insulating blocks have strong mechanical properties, carbon fixation properties and thermal conductivity. Among them, the addition of the above-mentioned weight parts of quicklime can increase the hardness and compressive strength of the self-insulating blocks and improve their service life on the one hand, and increase the carbon fixation effect of the self-insulating blocks on the other hand; the addition of catalysts can further improve the mechanical properties of the self-insulating blocks on the one hand, and accelerate the mineralization and curing process on the other hand, shortening the curing cycle; the phase change energy storage material has the characteristics of high energy storage density and high specific heat capacity, thereby improving the thermal conductivity and energy utilization rate of the self-insulating blocks; the addition of water reducer can also improve the mechanical strength of the slurry.

[0009] In the present application, the particle size of the quartz sand can be 50-100 mesh, and adding the above-mentioned quartz sand in parts by weight can increase the strength of the concrete.

[0010] In the present application, the strength grade of the cement is generally not less than 52.5 silicate cement. Considering the comprehensive cost, preferably, silicate cement with a strength grade of 52.5 is used.

[0011] In some feasible implementations, the silicon dioxide content in the quartz sand is ≥90%, and the mud content in the quartz sand is ≤5%. By adding the quartz sand of the above components, the strength of the building block can be increased.

[0012] In some feasible embodiments, the water reducer is a polycarboxylate water reducer. Polycarboxylate water reducer has excellent water reduction rate, fluidity, and permeability, and its addition can significantly enhance the mechanical strength of the self-insulating building block.

[0013] In some feasible embodiments, the catalyst includes a powder catalyst and a liquid catalyst, and the weight ratio of the powder catalyst to the liquid catalyst is (15-20):(1-5), preferably 20:1.

[0014] In some feasible embodiments, the liquid catalyst includes maleic acid, hydrogen peroxide, sodium hydroxide and distilled water, and the powder catalyst includes calcium carbonate, calcium silicate and calcium hydroxide.

[0015] In some feasible embodiments, the powder catalyst is composed of calcium carbonate, calcium silicate and calcium hydroxide in a weight ratio of (2-3):(3-5):(1-2), preferably 2:2:1.

[0016] The main component of the powder catalyst used in the present invention, calcium carbonate, can regulate the crystallization behavior of precipitation in aerated concrete and induce calcium silicate (C3S and C2S) in silicate concrete to participate in the reaction. At the same time, the calcium silicate in the powder catalyst can not only react with CO2, but also increase the mineralization rate and amount of silicate concrete. The silicate doping as a dispersant strengthens the internal diffusion of CO2 gas, especially the gas permeability in the early stage of the reaction. At the same time, the calcium silicate in the powder catalyst can react with CO2 and improve the mineralization rate and amount of silicate concrete. 2+ Ions have a very high binding capacity and can form complexes with liquid catalysts, which can quickly migrate in the pores and cracks of concrete. Calcium complexes react with CO3 in the pores and cracks. 2- A reaction occurs, generating CaCO3 crystal precipitation, further optimizing the pore structure of the concrete, and promoting the mineralization reaction, further improving the mechanical strength of the self-insulating blocks.

[0017] In some feasible implementations, the phase change energy storage material is paraffin phase change microcapsules. The use of microcapsule encapsulation can prevent leakage of the phase change energy storage material, thereby improving compatibility with concrete.

[0018] In another aspect, the present invention further provides a method for preparing the above-mentioned carbon-fixing lightweight composite self-insulating building block, the method comprising the following steps:

[0019] (1) weighing raw materials according to the proportion, wherein the aluminum powder paste is prepared into an aluminum powder paste suspension, and the remaining raw materials are mixed and stirred;

[0020] (2) introducing CO2 gas into the mixed raw materials for 60-120 seconds, then adding the aluminum powder paste suspension and continuing to stir to obtain a self-insulating building block wet material;

[0021] (3) injecting the wet material of the self-insulating building block into a mold for casting, and demoulding after curing;

[0022] (4) 8-12 hours after pouring, filling the heat-insulating core material and curing to obtain the carbon-fixing lightweight composite self-insulating building block.

[0023] In the present application, the stirring device generally adopts a common mixing and stirring device in the art, such as a stirrer.

[0024] The present invention adds CO2 gas during the raw material mixing process, so that the CO2 gas undergoes a mineralization reaction with the alkaline components in the concrete, achieving microcrystallization at an earlier stage. Compared with the traditional carbon dioxide mineralization curing process in which CO2 gas is added for mineralization reaction after the pouring stage is completed, the mechanical properties of the self-insulating blocks can be further improved.

[0025] In some feasible embodiments, in step (1), the mixing and stirring includes first stirring the cement, quartz sand and quicklime at a rotation speed of 35-45 r / min for 120-200 s to obtain a dry mixed material, and then adding the water reducer, catalyst, phase change energy storage material and water to the dry mixed material and stirring it for a second time at a rotation speed of 60 r / min for 60-90 s.

[0026] In some feasible embodiments, in step (2), the amount of CO2 gas introduced is 1.9-3.8 parts by weight, and the stirring time during the introduction of CO2 gas is 100-120 seconds. By adjusting the above CO2 gas incorporation parameters, the mechanical properties of the self-insulating building block are further improved.

[0027] In some feasible implementations, the stirring time is continued for 25-35 seconds.

[0028] In some feasible implementations, the pouring temperature is 40-55°C, and the curing condition is 30-40°C for 4-6 hours.

[0029] In some feasible implementations, the maintenance period is 28 days.

[0030] In some feasible embodiments, the thermal insulation core material in step (4) is at least one of expandable polystyrene board, extruded polystyrene foam board, rigid polyurethane and basalt rock wool. DETAILED DESCRIPTION

[0031] By reference to the following detailed description, examples, it is possible to more easily understand the embodiments of the present invention. However, the materials and methods described herein are not limited to the specific embodiments presented in the detailed description, examples. It should be appreciated that the exemplary embodiments herein are merely illustrations of the principles of the present invention. Without departing from the spirit and scope of the present invention, many modifications and adjustments will be apparent to those skilled in the art.

[0032] In the description of this embodiment, "several" means one or more, "many" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of "first" and "second" in the description is solely for the purpose of distinguishing technical features and is not to be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0033] In describing this embodiment, it should be noted that all ranges disclosed herein are to be understood to encompass any and all subranges subsumed therein. For example, the stated range "3% to 20%" should be considered to include any and all subranges beginning with a minimum of 3% or greater and ending with a maximum of 20% or less, such as 4% to 19%, or 4.5% to 15%, or 12% to 13%. Furthermore, all ranges disclosed herein are also considered to include the endpoints of the ranges, unless expressly stated otherwise. For example, the ranges "between 4 and 6," "4 to 6," or "4-6" should generally be considered to include the endpoints 4 and 6.

[0034] In the description of this embodiment, unless otherwise explicitly defined, terms such as "set," "install," and "connect" should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in this embodiment in conjunction with the specific content of the technical solution. The technical solution of the present invention is further described below with reference to exemplary embodiments.

[0035] The present embodiment provides a carbon-fixing lightweight composite self-insulating building block, which includes, by weight, 300-350 parts of cement, 100-175 parts of quartz sand, 25-50 parts of quicklime, 0.3-0.8 parts of aluminum paste, 0.7-2 parts of water reducer, 14-22 parts of catalyst, 10-20 parts of phase change energy storage material, and 170-230 parts of water.

[0036] In some embodiments, the carbon-fixing lightweight composite self-insulating building block includes, by weight, 320-350 parts of cement, 120-150 parts of quartz sand, 30-50 parts of quicklime, 0.5-0.7 parts of aluminum paste, 0.7-1 parts of water reducer, 10-15 parts of paraffin-based microcapsules, 14-20 parts of catalyst, and 170-200 parts of water.

[0037] In some embodiments, the carbon-fixing lightweight composite self-insulating building block includes, by weight, 300 parts of cement, 150 parts of quartz sand, 50 parts of quicklime, 0.5 parts of aluminum paste, 0.7 parts of water reducer, 10 parts of paraffin-based microcapsules, 14 parts of catalyst, and 200 parts of water.

[0038] In the present application, the strength grade of the cement is generally not less than 52.5 silicate cement. Considering the comprehensive cost, preferably, silicate cement with a strength grade of 52.5 is used.

[0039] In some embodiments, the silica content in the quartz sand is ≥90%, and the mud content in the quartz sand is ≤5%. Specifically, the silica content in the quartz sand can be 91%, 95%, 98%, and may be 100%, and the mud content in the quartz sand can be 4%, 3%, 2% or 1%, depending on actual needs.

[0040] In some embodiments, the water reducer is a polycarboxylate water reducer. In some embodiments, the water reduction rate of the water reducer is not less than 25%.

[0041] In other embodiments, the water reducer may be one or more of calcium lignin sulfonate, sodium lignin sulfonate, magnesium lignin sulfonate, maleic anhydride, and methacrylic acid.

[0042] In some embodiments, the catalyst includes a powder catalyst and a liquid catalyst, and the weight ratio of the powder catalyst to the liquid catalyst in the catalyst is (15-20):(1-5), for example, it can be 19:3, 15:4 or 17:5, and the value can be determined according to actual needs. Preferably, the weight ratio of the powder catalyst to the liquid catalyst is 20:1.

[0043] In some embodiments, the liquid catalyst includes maleic acid, hydrogen peroxide, sodium hydroxide, and distilled water, and the powder catalyst includes calcium carbonate, calcium silicate, and calcium hydroxide.

[0044] In some embodiments, the powder catalyst is composed of calcium carbonate, calcium silicate and calcium hydroxide in a weight ratio of (2-3):(3-5):(1-2), for example, it can be 2:3:1, 3:5:1, 2:5:1 or 3:3:2, and the value is determined according to actual needs, preferably 2:2:1.

[0045] In some embodiments, the phase change energy storage material is paraffin phase change microcapsules.

[0046] In the present application, the paraffin phase change microcapsules can adopt the following formula, which includes 70% paraffin (phase change enthalpy 180 J / g), 20% tetraethyl orthosilicate, 10% butyl titanate and 1% emulsifier (Span-80) by mass percentage. After forming the SiO2-TiO2 shell layer by the sol-gel method, it is vacuum dried at 60°C to obtain paraffin phase change microcapsules with a particle size D50 = 50±5 μm.

[0047] In some embodiments, the phase change energy storage material may also be one or more of calcium chloride hexahydrate, sodium sulfate decahydrate, and lithium nitrate trihydrate.

[0048] The present invention also provides a method for preparing the self-insulating building block, the method comprising the following steps:

[0049] (1) weighing raw materials according to the proportion, wherein the aluminum powder paste is prepared into an aluminum powder paste suspension, and the remaining raw materials are mixed and stirred;

[0050] (2) introducing CO2 gas into the mixed raw materials for 60-120 seconds, then adding the aluminum powder paste suspension and continuing to stir to obtain a self-insulating building block wet material;

[0051] (3) injecting the wet material of the self-insulating building block into a mold for casting, and demoulding after curing;

[0052] (4) 8-12 hours after pouring, filling the heat-insulating core material and curing to obtain the carbon-fixing lightweight composite self-insulating building block.

[0053] In some embodiments, in step (1), the mixing and stirring includes first stirring the cement, quartz sand and quicklime at a rotation speed of 35-45 r / min for 120-200 s to obtain a dry mixed material, and then adding the water reducer, catalyst, phase change energy storage material and water to the dry mixed material and stirring for a second time at a rotation speed of 60 r / min for 60-90 s.

[0054] In some embodiments, the amount of CO2 gas introduced in step (2) is 1.9-3.8 parts by weight, and the stirring time for introducing CO2 gas is 100-120s.

[0055] Preferably, in step (2), the amount of CO2 gas introduced is 1.9 parts by weight, and the stirring time for introducing CO2 gas is 120s.

[0056] In some embodiments, in step (2), the stirring time is continued for 25-35 seconds.

[0057] In some embodiments, in step (3), the pouring temperature is 40-55°C, and the curing conditions are 30-40°C for 4-6 hours.

[0058] In some embodiments, in step (4), the curing period is 28 days.

[0059] The present application is further explained below with reference to the embodiments.

[0060] The raw materials used in the examples and comparative examples of the present application are all commercially available. The quicklime used is Grade I quicklime in the JC / T621-021 standard. The manufacturer of the polycarboxylate water reducer is Jiangsu Subote New Materials Co., Ltd., and the model is PCA -R; the manufacturer of cement model P·O 52.5 is Jidong Cement; the manufacturer of quartz sand is Shaanxi Lei Ai Fende Industrial Co., Ltd., and the model is 200 mesh quartz powder.

[0061] Example 1

[0062] The present embodiment provides a carbon-fixing lightweight composite self-insulating building block and a preparation method. The carbon-fixing lightweight composite self-insulating building block includes, by weight: a first component: 300 parts of cement, 150 parts of quartz sand, 50 parts of quicklime, 0.5 parts of aluminum powder paste, 0.7 parts of polycarboxylic acid water reducer, 10 parts of paraffin-based microcapsules, 14 parts of catalyst, and 200 parts of water, wherein the silicon dioxide content in the quartz sand is 90%, and the mud content of the quartz sand is 5%, the catalyst includes a liquid catalyst of maleic acid, hydrogen peroxide, sodium hydroxide and distilled water, and a powder catalyst composed of calcium carbonate, calcium silicate and calcium hydroxide in a weight ratio of 2:2:1, and the weight ratio of the powder catalyst to the liquid catalyst is 20:1; the second component: EPS insulation board.

[0063] The preparation method of the self-insulating building block is specifically as follows:

[0064] 1) Mix cement, quartz sand and quicklime and stir at a speed of 40 r / min for 200 s to obtain a dry mix;

[0065] 2) adding a water reducer, a catalyst, paraffin-based microcapsules and water to the dry mixed material for secondary stirring, stirring at a speed of 60 r / min for 60 seconds, then introducing CO2 into the stirring chamber, and keeping the stirrer in operation for 120 seconds, and then adding aluminum powder paste and stirring for 30 seconds to obtain a self-insulating building block wet material;

[0066] 3) The self-insulating block wet material is injected into the mold at a pouring temperature of 50° C., and demoulding is performed after curing in a 40° C. environment for 4 hours. After 8 hours, the hollow of the self-insulating block is filled with an expandable polystyrene board (EPS) insulation board, and then sent to the curing site for curing.

[0067] Example 2

[0068] The present embodiment provides a carbon-fixing lightweight composite self-insulating building block and a preparation method. The carbon-fixing lightweight composite self-insulating building block comprises, by weight: a first component: 350 parts of cement, 120 parts of quartz sand, 30 parts of quicklime, 0.7 parts of aluminum paste, 0.7 parts of polycarboxylic acid water reducer, 15 parts of paraffin-based microcapsules, 14 parts of catalyst, and 200 parts of water, wherein the silicon dioxide content in the quartz sand is 95%, and the mud content of the quartz sand is 3%, the catalyst comprises a liquid catalyst of maleic acid, hydrogen peroxide, sodium hydroxide and distilled water, and a powder catalyst composed of calcium carbonate, calcium silicate and calcium hydroxide in a weight ratio of 2:2:1, and the weight ratio of the powder catalyst to the liquid catalyst is 20:1; the second component: EPS insulation board.

[0069] The preparation method of the self-insulating building block is specifically as follows:

[0070] 1) Mix cement, quartz sand and quicklime and stir at a speed of 40 r / min for 200 s to obtain a dry mix;

[0071] 2) adding a water reducer, a catalyst, paraffin-based microcapsules and water to the dry mixed material for secondary stirring, stirring at a speed of 60 r / min for 60 seconds, then introducing CO2 into the stirring chamber, and keeping the stirrer in operation for 120 seconds, and then adding aluminum powder paste and stirring for 30 seconds to obtain a self-insulating building block wet material;

[0072] 3) The wet material of the self-insulating block is injected into the mold at a pouring temperature of 50°C. After curing for 4 hours in a 40°C environment, the mold is demoulded. After 8 hours, the hollow of the self-insulating block is filled with XPS insulation board, and then the block is sent to the curing site for curing.

[0073] Example 3

[0074] The present embodiment provides a carbon-fixing lightweight composite self-insulating building block and a preparation method. The carbon-fixing lightweight composite self-insulating building block comprises, by weight: a first component: 320 parts of cement, 150 parts of quartz sand, 30 parts of quicklime, 0.5 parts of aluminum paste, 0.7 parts of polycarboxylic acid water reducer, 12 parts of paraffin-based microcapsules, 14 parts of catalyst, and 200 parts of water, wherein the silica content in the quartz sand is 98%, and the mud content of the quartz sand is 2%, the catalyst comprises a liquid catalyst of maleic acid, hydrogen peroxide, sodium hydroxide and distilled water, and a powder catalyst composed of calcium carbonate, calcium silicate and calcium hydroxide in a weight ratio of 2:2:1, and the weight ratio of the powder catalyst to the liquid catalyst is 20:1; the second component: rigid polyurethane.

[0075] The preparation method of the self-insulating building block is specifically as follows:

[0076] 1) Mix cement, quartz sand and quicklime and stir at a speed of 40 r / min for 200 s to obtain a dry mix;

[0077] 2) adding a water reducer, a catalyst, paraffin-based microcapsules and water to the dry mixed material for secondary stirring, stirring at a speed of 60 r / min for 60 seconds, then introducing CO2 into the stirring chamber, and keeping the stirrer in operation for 120 seconds, and then adding aluminum powder paste and stirring for 30 seconds to obtain a self-insulating building block wet material;

[0078] 3) The wet material of the self-insulating building block is injected into the mold at a pouring temperature of 50° C., and demoulded after curing in a 40° C. environment for 4 hours. After 8 hours, the hollow of the self-insulating building block is filled with rigid polyurethane, and then sent to a curing site for curing.

[0079] Example 4

[0080] The present embodiment provides a carbon-fixing lightweight composite self-insulating building block and a preparation method. The carbon-fixing lightweight composite self-insulating building block includes, by weight: a first component: 350 parts of cement, 120 parts of quartz sand, 30 parts of quicklime, 0.7 parts of aluminum paste, 0.7 parts of polycarboxylic acid water reducer, 15 parts of paraffin-based microcapsules, 16 parts of catalyst, and 200 parts of water, wherein the silicon dioxide content in the quartz sand is 99%, and the mud content of the quartz sand is 1%, the catalyst includes a liquid catalyst of maleic acid, hydrogen peroxide, sodium hydroxide and distilled water, and a powder catalyst composed of calcium carbonate, calcium silicate and calcium hydroxide in a weight ratio of 2:2:1, and the weight ratio of the powder catalyst to the liquid catalyst is 20:1; the second component: basalt rock wool insulation board.

[0081] The preparation method of the self-insulating building block is specifically as follows:

[0082] 1) Mix cement, quartz sand and quicklime and stir at a speed of 40 r / min for 200 s to obtain a dry mix;

[0083] 2) adding a water reducer, a catalyst, paraffin-based microcapsules and water to the dry mixed material for secondary stirring, stirring at a speed of 60 r / min for 60 seconds, then introducing CO2 into the stirring chamber, and keeping the stirrer in operation for 120 seconds, and then adding aluminum powder paste and stirring for 30 seconds to obtain a self-insulating building block wet material;

[0084] 3) The self-insulating block wet material is injected into the mold at a pouring temperature of 50° C., and demoulding is performed after curing in a 40° C. environment for 4 hours. After 8 hours, the hollow of the self-insulating block is filled with an extruded polystyrene foam board (XPS) insulation board, and then sent to a curing site for curing.

[0085] Example 5

[0086] The present embodiment provides a carbon-fixing lightweight composite self-insulating building block and a preparation method. The carbon-fixing lightweight composite self-insulating building block comprises, by weight: a first component: 350 parts of cement, 120 parts of quartz sand, 30 parts of quicklime, 0.57 parts of aluminum paste, 0.7 parts of polycarboxylic acid water reducer, 15 parts of paraffin-based microcapsules, 14 parts of catalyst, and 200 parts of water, wherein the silicon dioxide content in the quartz sand is 90%, and the mud content of the quartz sand is 5%, the catalyst comprises a liquid catalyst of maleic acid, hydrogen peroxide, sodium hydroxide and distilled water, and a powder catalyst composed of calcium carbonate, calcium silicate and calcium hydroxide in a weight ratio of 2:2:1, and the weight ratio of the powder catalyst to the liquid catalyst is 20:1; the second component: EPS insulation board.

[0087] The preparation method of the self-insulating building block is specifically as follows:

[0088] 1) Mix cement, quartz sand and quicklime and stir at a speed of 40 r / min for 200 s to obtain a dry mix;

[0089] 2) adding a water reducer, a catalyst, paraffin-based microcapsules and water to the dry mixed material for secondary stirring, stirring at a speed of 60 r / min for 60 seconds, then introducing CO2 into the stirring chamber, and keeping the stirrer in operation for 120 seconds, and then adding aluminum powder paste and stirring for 30 seconds to obtain a self-insulating building block wet material;

[0090] 3) The wet material of the self-insulating block is injected into the mold at a pouring temperature of 50° C., and demoulded after curing in a 40° C. environment for 4 hours. After 8 hours, the hollow of the self-insulating block is filled with EPS insulation board, and then sent to the curing site for curing.

[0091] Comparative Example 1

[0092] This comparative example provides a carbon-fixing lightweight composite self-insulating building block and a preparation method. The carbon-fixing lightweight composite self-insulating building block comprises, by weight, the following components: a first component: 350 parts cement, 120 parts quartz sand, 30 parts quicklime, 0.7 parts aluminum paste, 0.7 parts polycarboxylate superplasticizer, 14 parts catalyst, and 200 parts water. The silica content of the quartz sand is 90%, and the mud content is 5%. The catalyst comprises a liquid catalyst composed of maleic acid, hydrogen peroxide, sodium hydroxide, and distilled water, and a powder catalyst composed of calcium carbonate, calcium silicate, and calcium hydroxide in a weight ratio of 2:2:1, with the weight ratio of the powder catalyst to the liquid catalyst being 20:1. The second component comprises EPS insulation board. The preparation method of this self-insulating building block is the same as in Example 1.

[0093] Comparative Example 2

[0094] This comparative example provides a carbon-fixing lightweight composite self-insulating building block and a preparation method. The carbon-fixing lightweight composite self-insulating building block comprises, by weight: a first component: 350 parts of cement, 120 parts of quartz sand, 30 parts of quicklime, 0.7 parts of aluminum paste, 0.7 parts of polycarboxylic acid water reducer, 15 parts of paraffin-based microcapsules, 14 parts of catalyst, and 200 parts of water, wherein the silicon dioxide content in the quartz sand is 90%, and the mud content of the quartz sand is 5%, the catalyst comprises a liquid catalyst of maleic acid, hydrogen peroxide, sodium hydroxide and distilled water, and a powder catalyst composed of calcium carbonate, calcium silicate and calcium hydroxide in a weight ratio of 2:2:1, and the weight ratio of the powder catalyst to the liquid catalyst is 20:1; the second component: EPS insulation board.

[0095] The preparation method of the self-insulating building block is specifically as follows:

[0096] 1) Mix cement, quartz sand and quicklime and stir at a speed of 40 r / min for 200 s to obtain a dry mix;

[0097] 2) adding a water reducer, a catalyst, paraffin-based microcapsules and water to the dry mixed material for secondary stirring, and stirring at a speed of 60 r / min for 200 s to obtain a self-insulating building block wet material;

[0098] 3) The wet material of the self-insulating block is injected into the mold at a pouring temperature of 50° C., and demoulded after curing in a 40° C. environment for 4 hours. After 8 hours, the hollow of the self-insulating block is filled with EPS insulation board, and then sent to the curing site for curing.

[0099] Comparative Example 3

[0100] This comparative example provides a carbon-fixing lightweight composite self-insulating building block and a preparation method. The carbon-fixing lightweight composite self-insulating building block comprises, by weight: a first component: 350 parts of cement, 120 parts of quartz sand, 30 parts of quicklime, 0.2 parts of aluminum paste, 0.7 parts of polycarboxylic acid water reducer, 15 parts of paraffin-based microcapsules, 14 parts of catalyst, and 200 parts of water, wherein the silicon dioxide content in the quartz sand is 90%, and the mud content of the quartz sand is 5%, the catalyst comprises a liquid catalyst of maleic acid, hydrogen peroxide, sodium hydroxide and distilled water, and a powder catalyst composed of calcium carbonate, calcium silicate and calcium hydroxide in a weight ratio of 2:2:1, and the weight ratio of the powder catalyst to the liquid catalyst is 20:1; the second component: EPS insulation board.

[0101] The preparation method of the self-insulating building block is the same as that of Example 1.

[0102] Comparative Example 4

[0103] This comparative example provides a carbon-fixing lightweight composite self-insulating building block and a preparation method. The carbon-fixing lightweight composite self-insulating building block comprises, by weight: a first component: 350 parts cement, 120 parts quartz sand, 30 parts quicklime, 0.7 parts aluminum paste, 0.7 parts polycarboxylate superplasticizer, 25 parts paraffin-based microcapsules, 14 parts catalyst, and 200 parts water. The quartz sand has a silica content of 90% and a mud content of 5%. The catalyst comprises a liquid catalyst composed of maleic acid, hydrogen peroxide, sodium hydroxide, and distilled water, and a powder catalyst composed of calcium carbonate, calcium silicate, and calcium hydroxide in a weight ratio of 2:2:1, with the weight ratio of the powder catalyst to the liquid catalyst being 20:1. The second component: EPS insulation board.

[0104] The preparation method of the self-insulating building block is the same as that of Example 1.

[0105] Comparative Example 5

[0106] This comparative example provides a carbon-fixing lightweight composite self-insulating building block and a preparation method. The carbon-fixing lightweight composite self-insulating building block comprises, by weight: a first component: 350 parts cement, 120 parts quartz sand, 30 parts quicklime, 1 part aluminum paste, 0.7 part polycarboxylate superplasticizer, 15 parts paraffin-based microcapsules, 14 parts catalyst, and 200 parts water. The quartz sand has a silica content of 90% and a mud content of 5%. The catalyst comprises a liquid catalyst composed of maleic acid, hydrogen peroxide, sodium hydroxide, and distilled water, and a powder catalyst composed of calcium carbonate, calcium silicate, and calcium hydroxide in a weight ratio of 2:2:1, with the weight ratio of the powder catalyst to the liquid catalyst being 20:1. The second component: EPS insulation board.

[0107] The preparation method of the self-insulating building block is the same as that of Example 1.

[0108] Comparative Example 6

[0109] This comparative example provides a carbon-fixing lightweight composite self-insulating building block and its preparation method. The carbon-fixing lightweight composite self-insulating building block comprises, by weight: a first component comprising 350 parts cement, 120 parts quartz sand, 30 parts quicklime, 0.7 parts aluminum paste, 0.7 parts polycarboxylate superplasticizer, 10 parts paraffin-based microcapsules, and 200 parts water. The silica content of the quartz sand is 90%, and the mud content is 5%. A second component comprises EPS insulation board. The preparation method of this self-insulating building block is the same as that of Example 1.

[0110] The parameter comparison of the above embodiment and comparative example is shown in Table 1.

[0111] Table 1

[0112]

[0113]

[0114] The compressive strength, carbon fixation rate, dry density and thermal conductivity of the self-insulating blocks obtained in the above examples and comparative examples were tested, and the results are shown in Table 2 below:

[0115] Table 2

[0116]

[0117] Detection method

[0118] Compressive strength test method

[0119] According to the test requirements of GB / T4111 "Test Methods for Concrete Blocks and Bricks", before testing, remove particles and debris between the compressive surface of the specimen and the pressure plate. The two sections of the specimen are the compressive surfaces. The pressure position should be aligned with the center of the pressure plate and the bottom plate. Load at a relatively appropriate speed until the specimen fails. Record the failure load and the size of the compressive surface of the specimen at this time. The compressive strength f of the specimen is calculated according to the following formula, accurate to 0.01MPa:

[0120]

[0121] Where, f: compressive strength of the specimen, in megapascals, MPa;

[0122] P: maximum breaking load, in Newton, N;

[0123] S: pressure surface area, in square millimeters, mm 2

[0124] Dry density test method

[0125] According to the test requirements of GB / T11969-2020 "Test method for properties of autoclaved aerated concrete", the dry density of the specimen is measured and calculated according to the following steps.

[0126] (1) Take a set of specimens and measure the axial dimensions of length, width, and height to the nearest 0.1 mm. Calculate the volume of the specimens, denoted by V. Then weigh the mass of the specimens, denoted by M, to the nearest 1 g.

[0127] (2) Place the specimen in an electric blast drying oven and keep it at (60±5)℃ for 24h, then at (80±5)℃ for 24h, and then dry it at (105±5)℃ until it reaches constant mass, which is represented by M0. Constant mass means that the difference in mass between the two drying times does not exceed 2g at an interval of 4h.

[0128] (3) Calculate the dry density of the specimen:

[0129]

[0130] Where:

[0131] r0—dry density, unit is kg / m 3 ;

[0132] M0—mass of the specimen after drying, in g;

[0133] V—specimen volume, in mm 3 .

[0134] Carbon fixation rate test method

[0135] The carbon fixation rate is calculated using the mass method. The mineralized and unmineralized test blocks are dried and their masses are subtracted.

[0136] m CO2 =m a fter-m be fore

[0137] where m before is the drying mass of the unmineralized test block m after The drying mass of the mineralized test block, the mass after mineralization and the mass of the unmineralized test block are all taken as the average value of three test blocks.

[0138] In summary, the calculation formula for carbon fixation rate is:

[0139]

[0140] Thermal conductivity test method

[0141] After watering and curing, remove the 40mm x 40mm x 40mm cubic specimen and dry it at 105°C to constant weight. Use a 5501 probe, place it between the two sample surfaces, and secure it to the test stand within the sample compartment. Adjust the sample and probe temperatures to the same level before testing. If the test sample is a hard, bulk material, clamp the probe tightly to ensure close contact between the two sample surfaces. Thermal conductivity testing is performed using a thermal conductivity meter.

[0142] By comparing the relevant test results of the self-insulating building blocks of the examples and comparative examples, it can be seen that the parameters related to the catalyst, aluminum powder paste, phase change energy storage material, and CO2 gas have a significant impact on the mechanical strength, carbon fixation rate, and thermal conductivity of the self-insulating building blocks. Specifically, by comparing Example 1 with Comparative Examples 1 and 4, it can be seen that the self-insulating building blocks without the addition of the phase change energy storage material paraffin-based microcapsules, although the mechanical properties and carbon fixation rate are improved, the thermal conductivity is significantly increased, further reducing the thermal insulation performance of the building blocks. However, if the amount of paraffin-based microcapsules added is too much, exceeding the range defined by the claims of the present invention, the mechanical properties of the self-insulating building blocks will be significantly reduced.

[0143] Comparing Example 1 with Comparative Example 2 shows that not introducing CO2 gas can affect the dry density of the blocks to some extent, thereby reducing their water retention. Comparing Example 1 with Comparative Examples 3 and 5 shows that the addition of aluminum paste has a positive effect on the carbon fixation rate of the blocks. However, adding an amount exceeding the claimed range significantly reduces the mechanical strength of the self-insulating blocks.

[0144] By comparing Example 1 and Comparative Example 6, it can be seen that the addition of the catalyst can significantly improve the compressive strength of the self-insulating building block.

[0145] The above is a further detailed description of the present invention and should not be considered as a limitation on the specific implementation of the present invention. For those skilled in the art, simple deductions or substitutions that do not depart from the concept of the present invention are within the scope of protection of the present invention.

Claims

1. A carbon-fixing lightweight composite self-insulating building block, characterized in that: The carbon-fixing lightweight composite self-insulating building block comprises, by weight, 300-350 parts of cement, 100-175 parts of quartz sand, 25-50 parts of quicklime, 0.3-0.8 parts of aluminum paste, 0.7-2 parts of water reducer, 14-22 parts of catalyst, 10-20 parts of phase change energy storage material, and 170-230 parts of water.

2. The carbon-fixing lightweight composite self-insulating building block according to claim 1, characterized in that: The cement is silicate cement with a strength grade not less than 52.

5.

3. The carbon-fixing lightweight composite self-insulating building block according to claim 1, characterized in that: The silicon dioxide content in the quartz sand is ≥90%, and the mud content in the quartz sand is ≤5%.

4. The carbon-fixing lightweight composite self-insulating building block according to claim 1, characterized in that: The water reducer is a polycarboxylate water reducer.

5. The carbon-fixing lightweight composite self-insulating building block according to claim 1, characterized in that: The catalyst includes a powder catalyst and a liquid catalyst, and the weight ratio of the powder catalyst to the liquid catalyst is (15-20):(1-5).

6. The carbon-fixing lightweight composite self-insulating building block according to claim 5, characterized in that: The liquid catalyst includes maleic acid, hydrogen peroxide, sodium hydroxide and distilled water, and the powder catalyst includes calcium carbonate, calcium silicate and calcium hydroxide.

7. The carbon-fixing lightweight composite self-insulating building block according to claim 6, characterized in that: The powder catalyst consists of calcium carbonate, calcium silicate and calcium hydroxide in a weight ratio of (2-3):(3-5):(1-2).

8. The carbon-fixing lightweight composite self-insulating building block according to claim 1, characterized in that: The phase change energy storage material is paraffin phase change microcapsule.

9. A method for preparing a carbon-fixing lightweight composite self-insulating building block according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: (1) Weighing raw materials according to the proportion, wherein the aluminum powder paste is prepared into an aluminum powder paste suspension, and the remaining raw materials are mixed and stirred; (2) introducing CO2 gas into the mixed raw materials for 60-120 seconds, then adding the aluminum powder paste suspension and continuing to stir to obtain a self-insulating building block wet material; (3) injecting the wet material of the self-insulating building block into a mold for casting, and demoulding after curing; (4) 8-12 hours after pouring, filling the heat-insulating core material and curing to obtain the carbon-fixing lightweight composite self-insulating building block.

10. The preparation method according to claim 9, characterized in that The following conditions must be met: a. In step (1), the mixing and stirring comprises first stirring the cement, quartz sand and quicklime at a rotation speed of 35-45 r / min for 120-200 s to obtain a dry mixed material, then adding the water reducer, catalyst, phase change energy storage material and water to the dry mixed material and stirring for a second time at a rotation speed of 60 r / min for 60-90 s; b. In the step (2), the amount of CO2 gas introduced is 1.9-3.8 parts by weight, and the stirring time of the CO2 gas introduction is 100-120s; c. In step (2), the stirring time is continued for 25-35s; d. In step (3), the pouring temperature is 40-55°C, and the curing condition is 30-40°C for 4-6h; e. In step (4), the curing period is 28 days.

11. The preparation method according to claim 10, characterized in that: The thermal insulation core material in step (4) is at least one of expandable polystyrene board, extruded polystyrene foam board, rigid polyurethane and basalt rock wool.

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