Method for resourceful treatment of construction mixed garbage

Abstract

The application provides a resourceful treatment method of construction mixed garbage, comprising the following steps: S1, providing construction mixed garbage; S2, separating first construction garbage from the construction mixed garbage, wherein the first construction garbage comprises broken bricks and concrete blocks; S3, crushing the first construction garbage to obtain second construction garbage; mixing the second construction garbage to obtain third construction garbage; S4, jointly melting the third construction garbage, quartz sand, soda ash, calcite and fluorite to obtain a molten liquid; annealing the molten liquid to obtain an intermediate product after cooling; and S5, heating the intermediate product to 650-680 DEG C for 1-2 hours, then heating to 850-900 DEG C for 1-2 hours, and obtaining a final product after cooling. The application can convert a large amount of construction garbage into high-value construction materials, and the final product can be used as high-grade building decoration materials to replace marble and granite and other stone materials.

Description

Technical Field

[0001] This invention belongs to the field of building materials, and in particular relates to a method for the resource-based treatment of mixed construction waste. Background Technology

[0002] Cities are currently in a phase of rapid development, resulting in an unprecedented increase in construction waste. Directly dumping or burying construction waste along vacant lots, riverbanks, lakeshores, or secluded mountain areas not only damages the aesthetics of the environment but also affects the city's appearance, harms human health, and causes soil, groundwater, and air pollution. Therefore, the resource utilization of construction waste is a crucial measure to address the problems of high energy consumption, high pollution, high emissions, and low efficiency, and is an important way to save land and resources. For example, classifying construction waste and then crushing it using a crushing system can produce recycled aggregate that can be used as aggregate for paving airport roads, demonstrating a certain degree of utilization of construction waste. However, this method has a low degree of resource utilization and generates limited value, failing to transform large quantities of construction waste into high-value building materials.

[0003] Chinese invention patent application CN102219380A discloses a method for producing microcrystalline glass sheets using construction waste. The technical solution involves: mixing construction waste with other ingredients and then adding the mixture to a glass melting furnace to melt it into molten glass; quenching the molten glass in water to form glass particles, which are then dried using a dryer; classifying the glass particles using a vibrating screen; spreading the glass particles evenly in a refractory mold; placing the mold into a furnace for sintering and crystallization; and finally, grinding, polishing, and cutting the sintered glass sheets to obtain the finished microcrystalline glass. Although the above patent application utilizes construction waste to produce microcrystalline glass sheets, it involves applying construction waste to a sintering method for producing microcrystalline glass, which inevitably results in internal porosity, low strength, and poor overall performance.

[0004] Therefore, it is necessary to provide a resource-based treatment method for mixed construction waste to solve or at least alleviate the technical problem of how to convert large quantities of construction waste into high-value building materials. Summary of the Invention

[0005] The main objective of this invention is to provide a method for the resource-based treatment of mixed construction waste, aiming to solve the aforementioned technical problem of how to convert large quantities of construction waste into high-value building materials.

[0006] To achieve the above objectives, the present invention provides a method for the resource-based treatment of mixed construction waste, comprising the following steps:

[0007] S1 provides mixed construction waste;

[0008] S2, Separate a first construction waste from the mixed construction waste, the first construction waste comprising broken bricks and concrete blocks;

[0009] S3, the first construction waste is crushed to obtain the second construction waste; then, the second construction waste is mixed to obtain the third construction waste.

[0010] S4, the third construction waste and the additive are melted together to obtain a molten liquid; then, the molten liquid is annealed and cooled to obtain an intermediate product;

[0011] The additives include quartz sand, soda ash, calcite, and fluorite; the mass ratio of the third type of construction waste, the quartz sand, the soda ash, the calcite, and the fluorite is 100:15-20:10-15:4-8:6-10.

[0012] S5, the intermediate product is crystallized and cooled to obtain the final product;

[0013] The crystallization process includes: heating the intermediate product to 650-680℃ and holding it at that temperature for 1-2 hours, and then heating it to 850-900℃ and holding it at that temperature for 1-2 hours.

[0014] Furthermore, the mixed construction waste contains metals, organic matter, broken bricks, and concrete blocks.

[0015] Furthermore, the particle size of the second type of construction waste is no larger than the aperture of a 24-mesh sieve.

[0016] Furthermore, the mixing speed is 10-20 rpm, and the mixing time is 20-30 minutes.

[0017] Furthermore, the third type of construction waste contains silicon dioxide, aluminum oxide, calcium oxide, iron oxide, and magnesium oxide.

[0018] Furthermore, by mass percentage, the third type of construction waste contains 41-43% silicon dioxide, 7-9% aluminum oxide, 30-32% calcium oxide, 11-13% magnesium oxide, and 2-4% iron oxide.

[0019] Furthermore, the temperature of the melting treatment is 1400-1500℃, and the holding time of the melting treatment is 2-3 hours.

[0020] Furthermore, the annealing temperature is 550-600℃, and the annealing holding time is 1-2 hours.

[0021] Furthermore, during the annealing process, the molten metal is placed in a mold.

[0022] Furthermore, step S4 also includes cutting the intermediate product.

[0023] Compared with the prior art, the present invention has at least the following advantages:

[0024] This invention can transform large quantities of construction waste into high-value building materials, resulting in microcrystalline glass with excellent overall performance. This glass can serve as a high-grade building decoration material, replacing marble, granite, and other natural stones. This invention fully considers the impact of construction waste type and composition on the final product, as well as the compatibility of melting, annealing, and crystallization processes with the technical system of this invention. Therefore, this invention selects broken bricks and concrete blocks from mixed construction waste, crushes and mixes them, then combines them with specific admixtures, followed by melting, annealing, and crystallization in a specific manner. This yields high-quality and high-value building materials that meet the requirements of high construction waste utilization, low energy consumption in preparation, and good product performance.

[0025] This invention not only solves the problem of construction waste disposal but also provides the market with new high-grade decorative materials, resulting in significant economic and social benefits. Through optimized formula design, this invention achieves high utilization of construction waste, reducing dependence on natural resources and lowering energy consumption during the preparation process. The final product of this invention possesses excellent physicochemical properties, such as high hardness, wear resistance, and corrosion resistance, meeting the high standards required for building decorative materials. Furthermore, this invention considers environmental factors during the production process, reducing waste emissions and aligning with the concept of sustainable development. Due to the wide range of sources of construction waste, the technical solution of this invention has good adaptability and scalability, capable of meeting the construction waste disposal needs of different regions. Detailed Implementation

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. 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.

[0027] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0028] When numerical ranges are given in the embodiments, it should be understood that, unless otherwise stated in the present invention, both endpoints of each numerical range and any value between the two endpoints may be selected. Unless otherwise defined, all technical and scientific terms used in this invention, as well as the prior art known to those skilled in the art and the description of this invention, may be implemented using any prior art methods, devices, and materials similar to or equivalent to those described, used, or made of materials in the embodiments of this invention.

[0029] This invention provides a method for the resource recovery and treatment of mixed construction waste, comprising the following steps:

[0030] S1 provides mixed construction waste.

[0031] It should be understood that the mixed construction waste has a complex composition, typically containing metals, organic matter, broken bricks, and concrete blocks. If the mixed construction waste is directly processed for resource recovery, it will not only easily affect the quality of the final product, but also make it impossible to effectively control the content of components in the reaction system. Therefore, the mixed construction waste needs to be pre-separated.

[0032] S2, a first construction waste is separated from the mixed construction waste, the first construction waste comprising broken bricks and concrete blocks.

[0033] In separating the first construction waste, this invention removes metals and organic matter from the mixed construction waste, retaining broken bricks and concrete blocks. By using broken bricks and concrete blocks as the first construction waste, this invention ensures the composition of the construction waste, thereby guaranteeing the quality of the final product.

[0034] S3, the first construction waste is crushed to obtain the second construction waste; then, the second construction waste is mixed to obtain the third construction waste.

[0035] In this invention, after the crushing process, the particle size of the second construction waste is not greater than the aperture of a 24-mesh sieve; or, the product after the crushing process can be sieved to control the particle size of the second construction waste to be not greater than the aperture of a 24-mesh sieve.

[0036] In this invention, by performing the crushing and mixing processes, the composition of the third type of construction waste can be stabilized, thereby avoiding interference with the technical system of this invention. In this invention, the mixing speed is 10-20 revolutions per minute, and the mixing time is 20-30 minutes.

[0037] In this invention, the third type of construction waste contains silicon dioxide, aluminum oxide, calcium oxide, iron oxide, and magnesium oxide. By mass percentage and form of oxides, the third type of construction waste contains 41-43% silicon dioxide, 7-9% aluminum oxide, 30-32% calcium oxide, 11-13% magnesium oxide, and 2-4% iron oxide.

[0038] SiO2 and Al2O3 form the main framework of silicate glass and are the basic materials of glass-ceramics. Increasing the content of SiO2 and Al2O3 in the glass composition raises the melting and forming temperature, which is detrimental to melting and forming. However, increasing the content of SiO2 and Al2O3 reduces the crystallinity of the base glass, making the heat treatment process of glass-ceramics easier to control and beneficial for obtaining a large number of small grains. CaO and MgO are oxides in the glass network and play a similar role to alkali metal oxides in glass, providing "free oxygen," reducing glass viscosity, and increasing the glass's crystallinity. However, due to the presence of CaO and MgO, CaO... 2+ and Mg 2+ Due to its higher electricity price and smaller radius, its ionic potential is greater than that of alkali metal oxides, therefore its oxygen-extraction ability is greater than that of alkali metal oxides. Fe₂O₃ is a nucleating agent for glass-ceramics. 3+ The high charge and strong field of the cations have a significant accumulation effect on the glass structure, which can reduce the glass nucleation barrier and enable the glass-ceramic to have self-nucleation function.

[0039] S4, the third construction waste and the additive are melted together to obtain a melt; then, the melt is annealed and cooled to obtain an intermediate product.

[0040] In this invention, the additives include quartz sand, soda ash, calcite, and fluorite. By introducing the quartz sand, soda ash, calcite, and fluorite into combination with the third type of construction waste, based on the CaO·Al2O3·SiO2 system microcrystalline glass ternary phase diagram, SiO2, Al2O3, and CaO in the microcrystalline glass composition are selected in the main crystalline phase CS phase region to form microcrystalline glass.

[0041] In this invention, the mass ratio of the third type of construction waste, the quartz sand, the soda ash, the calcite, and the fluorite is 100:15-20:10-15:4-8:6-10. By controlling the mass ratio of the third type of construction waste, the quartz sand, the soda ash, the calcite, and the fluorite, multiple nucleating agents work together to promote the rapid precipitation of wollastonite crystals.

[0042] In this invention, the melting temperature is 1400-1500℃, and the holding time for the melting is 2-3 hours. By controlling the temperature and duration of the melting, sufficient time can be provided to ensure that the glass melt is fully melted and the composition is uniform.

[0043] In this invention, the annealing temperature is 550-600℃, and the holding time of the annealing is 1-2 hours; by controlling the temperature and duration of the melting treatment, stress in the glass can be eliminated.

[0044] In this invention, during the annealing process, the molten metal is placed in a mold, so that the cooled intermediate product can be formed in the mold.

[0045] In this invention, the intermediate product can be cut into multiple pieces before the crystallization process.

[0046] S5, the intermediate product is subjected to crystallization treatment, and the final product is obtained after cooling; the crystallization treatment includes: heating the intermediate product to 650-680℃ at 3-5℃ / min and holding it at 650-680℃ for 1-2h, and then continuing to heat it to 850-900℃ at 3-5℃ / min and holding it at 850-900℃ for 1-2h.

[0047] In this invention, by holding the glass at 650-680℃ for 1-2 hours, a large number of crystal nuclei can be generated in the glass block; by holding the glass at 850-900℃ for 1-2 hours, the crystal nuclei in the glass block can grow and form a large number of crystals, with the glass film interspersed among the crystals.

[0048] In this invention, after separating the metals and organic matter from the mixed construction waste, the remaining brick fragments and concrete blocks are crushed to a suitable particle size and mixed evenly. This mixture can be used as raw material for microcrystalline glass, thereby replacing marble, granite, and other natural stones as a high-end building decoration material. Specifically, this invention uses broken bricks and concrete blocks from construction waste as raw materials for microcrystalline glass. These are then melted and annealed with quartz sand, soda ash, calcite, and fluorite in a specific ratio. Nucleation and crystal growth are then carried out at a specific temperature to obtain microcrystalline glass based on a large amount of construction waste. Therefore, in this invention, construction waste constitutes a large proportion of the microcrystalline glass raw materials, allowing for rapid disposal and saving raw material costs. Furthermore, it utilizes construction waste effectively, ultimately yielding a high-value building material.

[0049] The following are specific examples of the present invention:

[0050] Example 1

[0051] A method for the resource recovery and treatment of mixed construction waste, comprising the following steps:

[0052] S1, Obtain mixed construction waste containing metal, organic matter, broken bricks, and concrete blocks.

[0053] S2 removes metals and organic matter from mixed construction waste, retaining broken bricks and concrete blocks as primary construction waste.

[0054] S3. The first construction waste is crushed and sieved through a 24-mesh sieve. The material passing through the sieve is taken as the second construction waste. Then, the second construction waste is mixed at 10 revolutions per minute for 30 minutes to obtain the third construction waste. The composition analysis of the third construction waste is shown in Table 1.

[0055] Table 1. Composition analysis of the third type of construction waste (wt%)

[0056] <![CDATA[SiO2]]> <![CDATA[Al2O3]]> CaO MgO <![CDATA[Fe2O3]]> other 42 8 31 12 3 4

[0057] S4. Mix the third type of construction waste, quartz sand, soda ash, calcite, and fluorite according to the mass ratio in Table 2 to obtain glass mixture.

[0058] Weigh 2500g of glass mixture, mix it evenly, and place it in a 2000mL corundum crucible. Melt it at 1430℃ for 2 hours. Quickly pour the molten glass into a preheated graphite mold and anneal it in an annealing furnace at 550℃ for 1 hour. After cooling to room temperature in the furnace, a glass sample (intermediate product) is obtained and cut into 6 glass blocks of 100mm×100mm.

[0059] Table 2 Mass ratio of glass mixture

[0060] Third construction waste Quartz sand soda ash calcite fluorite 100 18.5 12.8 4.3 7.1

[0061] S5. The glass block obtained after cutting is crystallized and then cooled to room temperature in the furnace to obtain microcrystalline glass.

[0062] In this embodiment, the crystallization process is as follows: the glass block (intermediate product) obtained after cutting is heated to 650°C at 3°C / min for 1 hour to generate a large number of crystal nuclei in the glass block; then, the temperature is increased to 850°C at 3°C / min and held for 1 hour to allow the crystal nuclei in the glass block to grow and form a large number of crystals, with the glass forming a thin film interspersed in the crystals.

[0063] Experimental results:

[0064] In this embodiment, the prepared microcrystalline glass was subjected to physicochemical testing, and the test results are shown in Table 3.

[0065] Table 3. Test results of microcrystalline glass

[0066]

[0067] Example 2

[0068] Compared to Example 1, this embodiment only adjusts the mass ratio of the third type of construction waste, quartz sand, soda ash, calcite, and fluorite, while keeping other conditions unchanged.

[0069] In this embodiment, the third type of construction waste, quartz sand, soda ash, calcite, and fluorite are mixed according to the mass ratio in Table 4.

[0070] Table 4 Mass Proportioning of Glass Mixture

[0071] Third construction waste Quartz sand soda ash calcite fluorite 100 15 10 4 7

[0072] Experimental results:

[0073] In this embodiment, the prepared microcrystalline glass was subjected to physicochemical testing, and the test results are shown in Table 5.

[0074] Table 5. Test Results of Microcrystalline Glass

[0075]

[0076] Example 3

[0077] Compared to Example 1, this embodiment only adjusts the mass ratio of the third type of construction waste, quartz sand, soda ash, calcite, and fluorite, while keeping other conditions unchanged.

[0078] In this embodiment, the third type of construction waste, quartz sand, soda ash, calcite, and fluorite are mixed according to the mass ratio in Table 6.

[0079] Table 6. Proportions of Glass Mixtures (wt%)

[0080] Third construction waste Quartz sand soda ash calcite fluorite 100 18 12 5 8

[0081] Experimental results:

[0082] In this embodiment, the prepared microcrystalline glass was subjected to physicochemical testing, and the test results are shown in Table 7.

[0083] Table 7. Test Results of Microcrystalline Glass

[0084]

[0085] Example 4

[0086] Compared to Example 1, this embodiment only adjusts the crystallization process, while keeping other conditions unchanged.

[0087] In this embodiment, the crystallization process is as follows: the glass block obtained after cutting is heated to 650°C at 5°C / min for 2 hours for nucleation, and then heated to 860°C at 3°C / min for 2 hours.

[0088] Experimental results:

[0089] In this embodiment, the prepared microcrystalline glass was subjected to physicochemical testing, and the test results are shown in Table 8.

[0090] Table 8. Test Results of Microcrystalline Glass

[0091]

[0092] Comparative Example 1

[0093] Compared to Example 1, this comparative example only adjusts the composition of the glass mixture while keeping other conditions unchanged.

[0094] In this comparative example, the glass mixture is made by mixing third-party construction waste, quartz sand, soda ash, calcite, fluorite, and zirconium oxide according to the mass ratio in Table 9.

[0095] Table 9 Mass Proportions of Glass Mixture

[0096] Third construction waste Quartz sand soda ash calcite fluorite Zirconia 100 18 10 4 7 1

[0097] Experimental results:

[0098] In this comparative example, the prepared microcrystalline glass was subjected to physicochemical tests, and the test results are shown in Table 10.

[0099] Table 10 Test Results of Microcrystalline Glass

[0100]

[0101] Comparative Example 2

[0102] Compared to Example 1, this comparative example only adjusted the crystallization process, while keeping other conditions unchanged.

[0103] In this comparative example, the crystallization process is as follows: the glass block obtained after cutting is heated to 880℃ at a rate of 5℃ / min and held at that temperature for 2 hours.

[0104] Experimental results:

[0105] In this comparative example, the prepared microcrystalline glass was subjected to physicochemical tests, and the test results are shown in Table 11.

[0106] Table 11 Test Results of Microcrystalline Glass

[0107]

[0108] Comparative Example 3

[0109] Compared to Example 1, this comparative example only adjusted the crystallization process, while keeping other conditions unchanged.

[0110] In this comparative example, the crystallization process was as follows: the glass block obtained after cutting was heated to 550℃ at 10℃ / min for nucleation for 3 hours, and then heated to 880℃ at 10℃ / min and held for 3 hours.

[0111] Experimental results:

[0112] In this comparative example, the prepared microcrystalline glass was subjected to physicochemical tests, and the test results are shown in Table 12.

[0113] Table 12 Test Results of Microcrystalline Glass

[0114]

[0115] The above technical solutions of the present invention are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present invention under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A method for the resource-based treatment of mixed construction waste, characterized in that, Including the following steps: S1 provides mixed construction waste; S2, Separate a first construction waste from the mixed construction waste, the first construction waste comprising broken bricks and concrete blocks; S3, the first construction waste is crushed to obtain the second construction waste; then, the second construction waste is mixed to obtain the third construction waste. The third type of construction waste contains 41-43% silicon dioxide, 7-9% aluminum oxide, 30-32% calcium oxide, 11-13% magnesium oxide, and 2-4% iron oxide. S4, the third construction waste and the additive are melted together to obtain a molten liquid; then, the molten liquid is annealed and cooled to obtain an intermediate product; The melting treatment temperature is 1400-1500℃, and the holding time of the melting treatment is 2-3 hours; the annealing treatment temperature is 550-600℃, and the holding time of the annealing treatment is 1-2 hours. The additives are quartz sand, soda ash, calcite, and fluorite; the mass ratio of the third type of construction waste, the quartz sand, the soda ash, the calcite, and the fluorite is 100:15-20:10-15:4-8:6-10. S5, the intermediate product is crystallized and cooled to obtain the final product; The crystallization process includes: heating the intermediate product to 650-680℃ and holding it at that temperature for 1-2 hours, and then heating it to 850-900℃ and holding it at that temperature for 1-2 hours.

2. The method for resource-based treatment of mixed construction waste according to claim 1, characterized in that, The mixed construction waste contains metal, organic matter, broken bricks, and concrete blocks.

3. The method for resource-based treatment of mixed construction waste according to claim 1, characterized in that, The particle size of the second type of construction waste is no larger than the aperture of a 24-mesh sieve.

4. The method for resource-based treatment of mixed construction waste according to claim 1, characterized in that, The mixing speed is 10-20 rpm, and the mixing time is 20-30 minutes.

5. The method for resource-based treatment of mixed construction waste according to claim 1, characterized in that, During the annealing process, the molten metal is placed in a mold.

6. The method for resource-based treatment of mixed construction waste according to claim 1, characterized in that, Step S4 further includes cutting the intermediate product.

Images