Composite nano-amine modified ecological brick and preparation method thereof
By incorporating nano-amine composite chemical additives into eco-bricks, the problem of low performance of eco-bricks has been solved, the strength and durability of eco-bricks have been improved, and higher value in building applications has been achieved.
Patent Information
- Application Number
- CN202511755020.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-26
- Publication Date
- 2026-02-10
AI Technical Summary
Existing eco-bricks have low performance and poor density, making it difficult to meet the strength and durability requirements of building materials, thus limiting their application in the construction field.
Nano-amine composite chemical additives, including hydrated calcium silicate nanomaterials and polycarboxylic acid ester ethers, are incorporated into construction waste and decoration waste to improve reactivity and optimize pore structure, thereby preparing composite nano-amine modified ecological bricks.
Significantly improves the strength and durability of eco-bricks, increasing the strength by 20%~25% and 10%~15% after 1 day and 7 days respectively, and optimizes the pore structure to make its performance closer to that of traditional building materials.
Smart Images
Figure CN121494443A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of environmental protection materials technology, and in particular to a composite nano-amine modified ecological brick and its preparation method. Background Technology
[0002] With the acceleration of urbanization and the rapid development of the construction industry, the amount of construction and decoration waste generated is constantly increasing, becoming a significant issue in current urban environmental management. According to statistics, construction and decoration waste has become a major component of urban solid waste, and its annual growth rate far exceeds that of other waste. Construction and decoration waste mainly includes waste materials from building demolition, decoration waste, and excavated soil from construction, and is diverse in type, containing various components such as concrete, bricks, steel bars, wood, plastics, and paper. The disorderly dumping of construction and decoration waste not only occupies a large amount of land resources but also easily causes environmental problems such as dust pollution and leachate pollution. Although there has been some progress in the recycling and treatment of construction and decoration waste, most of it is still disposed of primarily through landfill and stockpiling, resulting in low resource utilization and problems such as low processing efficiency and high costs. These wastes, due to their complex composition, uneven particle size, and high impurity content, are often difficult to use directly in the production of building materials. This results in a large amount of potential resources remaining unutilized, and the performance of these recycled materials often fails to meet the standards of traditional building materials, particularly in terms of strength, impermeability, and durability, thus limiting their application in the construction field. However, with the promotion of sustainable development concepts and the increasing demands for environmental protection, the resource utilization of construction and decoration waste has become an important task facing the global construction industry. Currently, construction and decoration waste is widely used to prepare eco-bricks, but its application remains limited due to its poor performance. Therefore, improving the performance, especially the strength, of eco-bricks prepared from construction and decoration waste is one of the current research focuses. Improving the strength of eco-bricks can not only enhance their application value in construction projects but also effectively reduce the environmental impact of construction and decoration waste, promoting the construction industry towards a green and low-carbon development direction. Therefore, developing a method to improve the performance of high-performance eco-bricks prepared from construction and decoration waste has important guiding significance for the sustainable development of building materials enterprises. Summary of the Invention
[0003] This invention proposes a composite nano-amine modified eco-brick and its preparation method, which solves the problems of low performance and poor density of eco-bricks in the prior art.
[0004] The technical solution of this invention is implemented as follows: A composite nano-amine modified ecological brick, wherein the ecological brick is made of construction waste, decoration waste, silicate cement and nano-amine composite chemical admixture; wherein the nano-amine composite chemical admixture is made of chemical admixture and nano-composite material; wherein the nano-composite material is made of hydrated calcium silicate nanomaterial and polycarboxylate ether (PCE).
[0005] In some embodiments, the construction waste includes one or more of concrete debris, bricks and slag; the decorative waste includes one or more of wall and floor material residues and glass waste.
[0006] In some embodiments, the silicate cement, by mass percentage, comprises 45% to 65% tricalcium silicate, 10% to 25% dicalcium silicate, 6% to 12% tricalcium aluminate, 6% to 20% tetracalcium aluminoferrite, and 3% to 8% other phases, the sum of which is 100% by mass; the particle size of the silicate cement is 0.3 to 75 μm.
[0007] In some embodiments, the chemical additive includes one of N,N,N',N'-tetra(2-hydroxyethyl)ethylenediamine (THEED) and N,N,N',N'-tetra(2-hydroxypropyl)ethylenediamine (THPED).
[0008] In some embodiments, the hydrated calcium silicate nanomaterial includes one or two of CSH gel, CFSH gel, and CASH gel.
[0009] In some embodiments, the chemical admixture is added at a rate of 0.02% to 0.1% of the mixture's mass. The nanocomposite material is added at a rate of 0.1% to 2% of the mixture's mass. The mixture consists of fine aggregate, powder, and silicate cement. The mass ratio of the chemical admixture to the nanocomposite material is 1:(8 to 18).
[0010] N,N,N',N'-Tetra(2-hydroxyethyl)ethylenediamine (THEED) and N,N,N',N'-Tetra(2-hydroxypropyl)ethylenediamine (THPED) have a certain reinforcing effect on cement. Hydrated calcium silicate nanomaterials (such as CSH gel) are used to significantly enhance the early strength of cement, while polycarboxylate ethers (PCE), being hydrophobic, are used as water-reducing agents. This invention further discovers that introducing the above-mentioned nano-amine composite chemical admixtures into construction waste composite materials improves cement hydration, reduces the water-cement ratio, and allows the nanomaterials to fill small pores, making the pore structure more compact. Simultaneously, it stimulates the interaction of ions in construction and decorative waste with cement, thereby significantly improving the overall mechanical properties and durability of eco-bricks.
[0011] This invention also provides a method for preparing composite nano-amine modified eco-bricks, comprising the following steps: (1) Screening construction waste and decoration waste to remove organic impurities and large particles, and then crushing and grinding them to prepare medium and fine aggregates and powder; (2) A nano-amine composite chemical admixture is obtained by mixing chemical admixtures, nanocomposite materials, and water; (3) The medium and fine aggregates and powder prepared in step (1) are thoroughly mixed with silicate cement to obtain a mixture; then the nano-amine composite chemical admixture solution is poured in and stirred to obtain cement clinker; (4) Pour the cement clinker prepared in step (3) into a mold and press it until the green body is formed; (5) Place the preform prepared in step (4) into a steam curing chamber and cure for 1-7 days to obtain the modified ecological brick finished product.
[0012] In some embodiments, the chemical admixture has a solid content of 85% to 90%, and is dispersed together with the nanocomposite material in water to form a nano-amine composite chemical admixture solution; in the nano-amine composite chemical admixture solution, the solid content of the chemical admixture is 1% to 5%, and the solid content of the nanocomposite material is 10% to 15%.
[0013] In some embodiments, the mass ratio of the chemical additive solution to the mixing water is 1:(2-6).
[0014] In some embodiments, the mixture in step (3) consists of: by mass percentage, 20% to 40% medium aggregate, 0% to 20% fine aggregate, 40% to 60% powder, and 10% to 20% silicate cement, the sum of which is 100% by mass percentage.
[0015] Compared with the prior art, the present invention has the following advantages: (1) The present invention improves the strength of modified ecological bricks by incorporating nano-amine composite chemical admixtures into a mixture of construction waste, decoration waste and silicate cement, thereby improving the reactivity of the mixture and optimizing the pore structure.
[0016] (2) The modified ecological bricks with nano-amine composite chemical admixtures have 20%~25% and 10%~15% higher strength at 1 day and 7 days, respectively, compared with ecological bricks without nano-amine composite chemical admixtures. Attached Figure Description
[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0018] Figure 1 This is the XRD pattern of silicate cement used in this invention.
[0019] Figure 2 This is a particle size distribution diagram of the silicate cement used in this invention. Detailed Implementation
[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0021] The composition of the mixtures used in the following examples and comparative examples is shown in Table 1.
[0022] Table 1. Composition of the mixture (wt%) .
[0023] Test method: Strength testing was conducted in accordance with the national standard GB / T2542-2012.
[0024] The determination of specific surface area shall be carried out in accordance with the national standard GB / T8074-2008.
[0025] The mineral content in silicate cement was obtained by XRD full spectrum fitting, and the calculation was performed using the HighScorePlus software package based on the Rietveld method.
[0026] Construction and decoration waste from a certain area was screened to remove organic impurities and large particles, then crushed and ground to prepare medium and fine aggregates and powder. The specific surface area of the powder was 340-360 m² / kg; the particle size of the fine aggregate was greater than 0.1 mm and less than or equal to 5 mm; the particle size of the medium aggregate was greater than 5 mm and less than or equal to 10 mm; the particle size of the powder was 0.3~75 μm; the chemical composition and mineral composition are shown in Table 2. The XRD pattern of silicate cement is shown below. Figure 1 As shown, the particle size distribution of silicate cement is as follows: Figure 2 As shown, by mass percentage, it includes 59% tricalcium silicate, 14% dicalcium silicate, 8% tricalcium aluminate, 12% tetracalcium aluminoferrite, and 7% other phases.
[0027] Table 2. Cement chemical composition and mineral composition (wt / %) .
[0028] Example 1 A CSH / PCE-THEED nano-amine composite chemical admixture with a dosage of 0.02% and 0.2% was stirred at a stirring speed of 100 r / min for 10 min to obtain a CSH / PCE-THEED nano-amine composite chemical admixture with a dosage of 0.02%-0.5%. Then, it was added to a mixer with medium and fine aggregates, powder and silicate cement according to the composition in Table 1 and a water-cement ratio of 0.25. After thorough mixing, a mixture was obtained. The prepared mixture was poured into a pressing mold, pressed and shaped, and steam cured for 1-7 days.
[0029] Example 2 A 0.04% THEED and a 0.5% CSH / PCE were mixed at a stirring speed of 100 r / min for 10 min to obtain a 0.04%-0.5% CSH / PCE-THEED nano-amine composite chemical admixture. Then, it was mixed with medium and fine aggregates, powder and silicate cement according to the composition in Table 1 and a water-cement ratio of 0.25 in a mixer to obtain a mixture. The prepared mixture was poured into a pressing mold, pressed and molded, and steam cured for 1-7 days.
[0030] Example 3 0.06% THEED and 0.8% CSH / PCE were stirred at a stirring speed of 100 r / min for 10 min to obtain a CSH / PCE-THEED nano-amine composite chemical admixture with a dosage of 0.02%-1%. Then, it was added to a mixer with medium and fine aggregates, powder and silicate cement according to the composition in Table 1 and a water-cement ratio of 0.25. After thorough mixing, the mixture was obtained. The prepared mixture was poured into a pressing mold, pressed and shaped, and steam cured for 1-7 days.
[0031] Example 4 0.08% THEED and 1.25% CSH / PCE were stirred at a stirring speed of 100 r / min for 10 min to obtain a CSH / PCE-THEED nano-amine composite chemical admixture with a dosage of 0.04%-1%. Then, it was added to a mixer with medium and fine aggregates, powder and silicate cement according to the composition in Table 1 and a water-cement ratio of 0.25. After thorough mixing, the mixture was obtained. The prepared mixture was poured into a pressing mold, pressed and shaped, and steam cured for 1-7 days.
[0032] Comparative Example 1 Deionized water, medium and fine aggregates, powder, and silicate cement are mixed in a mixer according to the composition in Table 1 and a water-cement ratio of 0.25 to obtain a mixture. The prepared mixture is poured into a pressing mold, pressed, and steam-cured for 1-7 days.
[0033] Comparative Example 2 Add 0.5% CSH / PCE, medium and fine aggregates, powder, and silicate cement to a mixer according to the composition in Table 1 and a water-cement ratio of 0.25. Mix thoroughly to obtain a mixture. Pour the prepared mixture into a pressing mold, press it into shape, and steam cure it for 1-7 days.
[0034] Comparative Example 3 THEED at a dosage of 0.04% was mixed with medium and fine aggregates and powder, and silicate cement according to the composition in Table 1 and a water-cement ratio of 0.25 in a mixer to obtain a mixture. The prepared mixture was poured into a pressing mold, pressed, and steam-cured for 1-7 days. The mass percentage of the mixture is shown in Table 1.
[0035] Table 3 Compressive strength of eco-bricks .
[0036] Table 3 shows the intensity comparison between the comparative example and the embodiment after 1 day and 7 days of steam curing.
[0037] As shown in Table 3, Comparative Example 2 (i.e., with 0.5% CSH / PCE added alone) showed an increase in strength in the early stage but a decrease in strength in the later stage compared to Comparative Example 1. Comparative Example 3 (i.e., with 0.02% THEED added alone) compensated for the strength reduction caused by air entrainment in the early stage due to steam curing. Examples 1, 2, 3, and 4 showed better strength performance than Comparative Examples 1 and 2, indicating that the use of nano-amine composite admixtures in this invention produced a synergistic effect, further optimizing the performance of the eco-bricks. Among them, Example 5 showed a 35.3% increase in mechanical strength at 1 day and a 12.2% increase at 7 days compared to Comparative Example 1, demonstrating good application results.
[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.
Claims
1. A composite nano-amine modified eco-brick, characterized in that, The eco-brick is made from construction waste, decoration waste, silicate cement, and nano-amine composite chemical admixtures; wherein the nano-amine composite chemical admixtures are made from chemical admixtures and nano-composite materials; and the nano-composite materials are made from hydrated calcium silicate nanomaterials and polycarboxylate ether (PCE).
2. The composite nano-amine modified ecological brick according to claim 1, characterized in that, The construction waste includes one or more of concrete debris, bricks and tiles, and slag; the decorative waste includes one or more of wall and floor material residues and glass waste.
3. The composite nano-amine modified ecological brick according to claim 1, characterized in that, The silicate cement, by mass percentage, comprises 45%~65% tricalcium silicate, 10%~25% dicalcium silicate, 6%~12% tricalcium aluminate, 6%~20% tetracalcium aluminoferrite, and 3%~8% other phases, the sum of which is 100% by mass; the particle size of the silicate cement is 0.3~75μm.
4. The composite nano-amine modified ecological brick according to claim 1, characterized in that, The chemical additives include one of N,N,N',N'-tetra(2-hydroxyethyl)ethylenediamine (THEED) and N,N,N',N'-tetra(2-hydroxypropyl)ethylenediamine (THPED).
5. The composite nano-amine modified ecological brick according to claim 1, characterized in that, The hydrated calcium silicate nanomaterials include one or two of CSH gel, CFSH gel, and CASH gel.
6. The composite nano-amine modified ecological brick according to claim 1, characterized in that, The chemical admixture is added at a rate of 0.02% to 0.1% of the mass of the mixture; the nanocomposite material is added at a rate of 0.1% to 2% of the mass of the mixture; the mixture is composed of fine aggregate, powder and silicate cement.
7. A method for preparing composite nano-amine modified eco-bricks as described in any one of claims 1-6, characterized in that, Includes the following steps: (1) Screening construction waste and decoration waste to remove organic impurities and large particles, and then crushing and grinding them to prepare medium and fine aggregates and powder; (2) A nano-amine composite chemical admixture is obtained by mixing chemical admixtures, nanocomposite materials, and water; (3) The medium and fine aggregates and powder prepared in step (1) are thoroughly mixed with silicate cement to obtain a mixture; then the nano-amine composite chemical admixture solution is poured in and stirred to obtain cement clinker; (4) Pour the cement clinker prepared in step (3) into a mold and press it until the green body is formed; (5) Place the preform prepared in step (4) into a steam curing chamber and cure for 1-7 days to obtain the modified ecological brick finished product.
8. The preparation method of the composite nano-amine modified ecological brick according to claim 7, characterized in that, The chemical admixture has a solid content of 85% to 90%, and it is dispersed together with the nanocomposite material in water to form a nano-amine composite chemical admixture solution; in the nano-amine composite chemical admixture solution, the solid content of the chemical admixture is 1% to 5%, and the solid content of the nanocomposite material is 10% to 15%.
9. The preparation method of the composite nano-amine modified ecological brick according to claim 7, characterized in that, The mass ratio of the chemical additive solution to the mixing water is 1:(2-6).
10. The method for preparing composite nano-amine modified ecological bricks according to claim 7, characterized in that, The mixture in step (3) consists of the following components by mass percentage: 20%–40% medium aggregate, 0%–20% fine aggregate, 40%–60% powder, and 10–20% silicate cement, with the sum of their mass percentages being 100%.