Preparation method of lightweight high-strength baking-free brick

Abstract

The invention relates to the technical field of baking-free brick preparation, and particularly discloses a preparation method of a light-weight high-strength baking-free brick, which comprises the following steps: step 1, weighing raw materials: accurately weighing the raw materials by using a high-precision electronic scale, ensuring that the weight of each raw material is accurate, and providing an accurate raw material proportioning basis for the subsequent preparation process; the concrete building slag aggregate is put into a jaw crusher, the crusher is started for coarse crushing operation, and the particle size of the concrete building slag aggregate is crushed to be 25 mm-30 mm. According to the method, a large amount of concrete building slag, clay ceramsite aggregate, building blocks, other building slag aggregate and other building waste are used as raw materials, reduction, harmlessness and recycling of the building waste are achieved, and according to estimation, the concrete building slag aggregate can be recycled. About 0.8 cubic meter of construction waste can be consumed when one cubic meter of the baking-free brick is produced, the pollution of the construction waste to the environment and the occupation of land resources are reduced, and the baking-free brick has the advantage of light weight after the clay ceramsite is added.

Description

Technical Field

[0001] The invention relates to the technical field of unfired brick preparation, in particular to a method for preparing lightweight and high-strength unfired bricks. Background Art

[0002] With the acceleration of urbanization, the construction industry is booming. In the process of building, renovating and demolishing buildings, a huge amount of solid waste such as abandoned sintered blocks, autoclaved blocks, concrete blocks and stones is generated. According to relevant statistical data, the total amount of construction waste generated in my country has reached billions of tons each year, and it is increasing year by year. If these wastes are randomly piled up or landfilled, they will not only occupy a large amount of precious land resources, but also cause serious damage to the ecological environment.

[0003] At present, although there have been some attempts to prepare construction waste into building materials, most of them have many shortcomings. On the one hand, the traditional preparation method is often to simply crush the waste and then mix it, lacking in-depth research on raw material particle grading, activity stimulation and other aspects, resulting in the difficulty of the product's strength and durability to reach a high level, unable to meet the construction project's demand for high-quality building materials. On the other hand, the unburned bricks produced by the existing preparation process are heavy in weight, and in actual use, they pose certain challenges to the overall load and labor intensity of workers.

[0004] In addition, traditional brick-making processes, such as clay-fired bricks, consume a large amount of land resources. According to incomplete statistics, about 12,000 to 15,000 acres of arable land are required to produce 100 million clay bricks. This is undoubtedly a huge waste of resources for a country like my country with a relatively small per capita arable land area. Moreover, the firing process of clay-fired bricks will emit a large amount of greenhouse gases, such as carbon dioxide and sulfur dioxide, which imposes a great burden on the environment and aggravates the trend of global warming. Therefore, it is urgent to develop a method for preparing lightweight, high-strength, unfired bricks that can efficiently utilize waste building materials and is innovative.

[0005] To this end, we proposed a method for preparing lightweight and high-strength unfired bricks to solve the above problems. Summary of the invention

[0006] The purpose of the present invention is to provide a method for preparing lightweight high-strength unfired bricks to solve the problem in the above background technology that the prior art cannot efficiently utilize waste building materials to reduce production costs.

[0007] To achieve the above object, the present invention provides a method for preparing lightweight high-strength unfired bricks, comprising the following steps:

[0008] Step 1: Weighing raw materials: Use a high-precision electronic scale to accurately weigh the raw materials to ensure that the weight of each raw material is accurate, providing an accurate basis for the raw material ratio for the subsequent preparation process;

[0009] Step 2: Crushing and screening of concrete slag aggregate. First, put the concrete slag aggregate into the jaw crusher, turn on the crusher for coarse crushing, and crush the concrete slag aggregate to a particle size of 25mm-30mm. Then, transfer the coarsely crushed concrete slag aggregate to the cone crusher for medium crushing, and further reduce its particle size to 5mm-10mm. Finally, use a vibrating screen to finely screen the medium-crushed concrete slag aggregate to select concrete slag aggregate particles with a particle size of 2mm-5mm, so that it meets the particle size requirements for preparing unburned bricks.

[0010] Step 3: Block and slag aggregate processing, clean the blocks and other slag aggregates thoroughly, carefully remove the wood, plastic, and metal impurities mixed in them, and use a combination of manual selection and mechanical screening to ensure that the impurities are completely removed. Then, put the cleaned blocks and other slag aggregates into a hammer crusher, start the crusher to crush the blocks and other slag aggregates into fine particles, and then screen the crushed blocks and other slag aggregates through a vibrating screen, and select particles with a particle size between 2mm and 5mm to meet the requirements of subsequent production;

[0011] Step 4: Clay pellets are screened and soaked. Use a sieve to screen out clay pellets with a particle size of 4mm-7mm. Then, put the screened clay pellets into a container filled with water and soak them for 6 hours to ensure that the clay pellets fully absorb water.

[0012] Step 5: Dry mix the raw materials. Add the processed concrete slag aggregate, building blocks and other construction slag aggregate, cement, clay ceramsite and fly ash into the forced mixer in sequence. Turn on the forced mixer, set the mixing speed and time, and mix at a speed of 100 revolutions per minute for 4 minutes to fully mix the various raw materials and achieve a dry-mixed uniform state.

[0013] Step 6: Prepare the water reducer solution. Pour an appropriate amount of water into a mixing container, then add the water reducer, turn on the stirrer, and stir at a speed of 120 revolutions per minute for 5 minutes to ensure that the water reducer is completely dissolved in the water to form a uniform water reducer solution.

[0014] Step 7: Prepare the slurry, slowly pour the prepared water reducing agent solution into the forced mixer, continue to stir the forced mixer, adjust the stirring speed to 150 revolutions per minute, stir for 6 minutes, so that the slurry has good fluidity and plasticity;

[0015] Step 8: Mold forming: quickly pour the stirred slurry into a mold of a predetermined shape and size, place the mold with the slurry on a vibrator, turn on the vibrator, and vibrate at a frequency of 3500 revolutions per minute for 4 minutes. At the same time, use a spatula to carefully trim the slurry on the edge and surface of the mold to ensure that the slurry is evenly distributed;

[0016] Step 9: Pre-curing and demoulding. Move the formed bricks together with the mold to the curing room. Set the temperature of the curing room to 20℃-30℃ and the relative humidity to 85%-90%. Let the bricks cure in the curing room for 24-36 hours. Then use a special demoulding tool to carefully demould the bricks from the mold.

[0017] Step 10: Post-curing: Place the demoulding bricks in the curing room for 21 days to ensure that the environmental conditions in the curing room are stable. The bricks can complete the subsequent curing process in a suitable environment and can be stacked and stored after curing.

[0018] Furthermore, the raw materials in step 1 specifically include 20-30 parts by weight of concrete slag aggregate, 20-30 parts of building blocks and other slag aggregates, 10-20 parts of cement, 6-10 parts of clay ceramsite, 1-5 parts of fly ash, 1-3 parts of water reducer, and 5-10 parts of water.

[0019] Furthermore, the concrete slag aggregate in step 1 is specifically the aggregate for preparing unburned bricks obtained by crushing and screening waste concrete blocks, and its main components are cement stone, sand and gravel.

[0020] Furthermore, the building blocks and other construction slag aggregates in step 1 are specifically discarded sintered blocks, autoclaved blocks, and discarded prefabricated mortar aggregates used for brick making after being processed, and contain silicate minerals.

[0021] Furthermore, in the step, the fly ash can be replaced with blast furnace slag powder, and the water reducing agent can be a polycarboxylic acid-based water reducing agent instead of a traditional naphthalene-based water reducing agent.

[0022] Furthermore, in the step 2, an impact crusher may be used instead of a hammer crusher to crush the blocks and slag aggregates.

[0023] Furthermore, during the curing stage in step eight and step nine, in addition to conventional natural curing combined with curing in a curing room, a curing method combining steam curing and natural curing can also be explored.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] First, in the present invention, a large amount of construction waste such as concrete slag, clay ceramsite aggregate, building blocks and other construction slag aggregate is used as raw materials, thereby achieving the reduction, harmlessness and resource utilization of construction waste. It is estimated that for every cubic meter of unburned brick produced by the present invention, about 0.8 cubic meters of construction waste can be consumed, thereby reducing the pollution of the environment and the occupation of land resources by construction waste, and the addition of clay ceramsite makes the unburned brick have the advantage of being lightweight;

[0026] Secondly, in the present invention, through reasonable raw material ratio and scientific preparation process, the lightweight high-strength unburned bricks have high compressive strength and flexural strength. The compressive strength can reach 30-40MPa, and the flexural strength can reach 4-6MPa, which can meet the strength requirements of wall materials in construction projects. At the same time, due to the addition of clay ceramsite, the density of the brick body is relatively low, generally 1400-1600kgm 3 It has a good lightweight effect, which can effectively reduce the weight of the building, reduce construction costs and labor intensity. In addition, the unburned brick also has good water resistance, and its water absorption rate is less than 10%, which can effectively prevent water penetration and extend the service life of the brick body;

[0027] Thirdly, in the present invention, the preparation method of the present invention is simple and easy to operate, the energy consumption in the production process is low, and the production cost is relatively low. Compared with the traditional unburned brick preparation process, the present invention improves the production efficiency and reduces the energy consumption by optimizing the raw material pretreatment, mixing, molding and maintenance links. At the same time, due to the large-scale use of construction waste as raw materials, the raw material cost is greatly reduced, which has high economic benefits and market competitiveness. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Embodiment 1:

[0031] See also Figure 1 The present invention provides a method for preparing lightweight high-strength unfired bricks, comprising the following steps:

[0032] Step 1: weighing raw materials, using a high-precision electronic scale to accurately weigh the raw materials to ensure that the weight of each raw material is accurate, providing an accurate raw material ratio basis for the subsequent preparation process. The raw materials in the step 1 specifically include 20 parts of concrete slag aggregate, 20 parts of building blocks and other building slag aggregates, 10 parts of cement, 6 parts of clay ceramsite, 1 part of fly ash, 1 part of water reducer, and 5 parts of water by weight. The concrete slag aggregate in the step 1 is specifically the aggregate for preparing unburned bricks obtained after crushing and screening of discarded concrete blocks, and the main components are cement stone, sand, and gravel. The building blocks and other building slag aggregates in the step 1 are specifically discarded sintered blocks, autoclaved blocks, and discarded prefabricated mortars. Aggregates used for brick making after treatment, the components contain silicate minerals. The fly ash in the step 1 can be replaced with blast furnace slag powder, and the water reducer can use a polycarboxylic acid-based water reducer instead of a traditional naphthalene-based water reducer;

[0033] Step 2: Crushing and screening of concrete slag aggregates. First, put the concrete slag aggregates into a jaw crusher, turn on the crusher for coarse crushing, and crush the concrete slag aggregates to a particle size of 25 mm. Then, transfer the coarsely crushed concrete slag aggregates to a cone crusher for medium crushing, and further reduce their particle size to 5 mm. Finally, use a vibrating screen to finely screen the medium-crushed concrete slag aggregates to screen out concrete slag aggregate particles with a particle size of 2 mm, so that they meet the particle size requirements for preparing unburned bricks. In the step 2, for building blocks and slag aggregates, an impact crusher can be used instead of a hammer crusher for crushing;

[0034] Step 3: Block and slag aggregate processing. Clean the blocks and other slag aggregates thoroughly, and carefully remove the wood, plastic, and metal impurities mixed in them. A combination of manual selection and mechanical screening can be used to ensure that the impurities are completely removed. Then, put the cleaned blocks and other slag aggregates into a hammer crusher, start the crusher to crush the blocks and other slag aggregates into fine particles, and then screen the crushed blocks and other slag aggregates through a vibrating screen, and select particles with a particle size of 2mm to meet the requirements of subsequent production;

[0035] Step 4: Screening and soaking the clay pellets. Use a sieve to screen out the clay pellets with a particle size of 4 mm. Then, put the screened clay pellets into a container filled with water and soak them for 6 hours to ensure that the clay pellets fully absorb water.

[0036] Step 5: Dry mix the raw materials. Add the processed concrete slag aggregate, building blocks and other construction slag aggregate, cement, clay ceramsite and fly ash into the forced mixer in sequence. Turn on the forced mixer, set the mixing speed and time, and mix at a speed of 100 revolutions per minute for 4 minutes to fully mix the various raw materials and achieve a dry-mixed uniform state.

[0037] Step 6: Prepare the water reducer solution. Pour an appropriate amount of water into a mixing container, then add the water reducer, turn on the stirrer, and stir at a speed of 120 revolutions per minute for 5 minutes to ensure that the water reducer is completely dissolved in the water to form a uniform water reducer solution.

[0038] Step 7: Prepare the slurry, slowly pour the prepared water reducing agent solution into the forced mixer, continue to stir the forced mixer, adjust the stirring speed to 150 revolutions per minute, stir for 6 minutes, so that the slurry has good fluidity and plasticity;

[0039] Step 8: Mold forming: quickly pour the stirred slurry into a mold of a predetermined shape and size, place the mold with the slurry on a vibrator, turn on the vibrator, and vibrate at a frequency of 3500 revolutions per minute for 4 minutes. At the same time, use a spatula to carefully trim the slurry on the edge and surface of the mold to ensure that the slurry is evenly distributed;

[0040] Step 9: Preliminary curing and demoulding. Move the formed bricks together with the molds to the curing room. Set the temperature of the curing room to 20°C and the relative humidity to 85%. Allow the bricks to cure in the curing room for 24 hours. Then use a special demoulding tool to carefully demould the bricks from the mold. In the curing stage of Steps 8 and 9, in addition to conventional natural curing combined with curing in a curing room, you can also explore the use of steam curing combined with natural curing for curing.

[0041] Step 10: Post-curing, keep the demoulding bricks in the curing room for 21 days to ensure that the environmental conditions in the curing room are stable, so that the bricks can complete the subsequent curing process in a suitable environment, and then stack them for storage after curing. Use clay pellets as aggregates and adjust the formula according to product requirements to achieve lightweight and increase the thermal insulation and sound insulation properties of the product. The soaking pretreatment of clay pellets can ensure that the density is equivalent to that of other aggregates during the mixing and vibration process, and the distribution is uniform. In addition, the advance soaking pretreatment can effectively prevent the polymer slurry from flowing into the voids of the clay pellets, ensuring the stability of the product quality while providing moisture in the hydration reaction during the curing stage, forming self-curing and preventing the cracking of unfired bricks.

[0042] Embodiment 2:

[0043] See also Figure 1 The present invention provides a method for preparing lightweight high-strength unfired bricks, comprising the following steps:

[0044] Step 1: weighing raw materials, using a high-precision electronic scale to accurately weigh the raw materials to ensure that the weight of each raw material is accurate, providing an accurate raw material ratio basis for the subsequent preparation process. The raw materials in the step 1 specifically include 25 parts of concrete slag aggregate, 25 parts of building blocks and other building slag aggregate, 12 parts of cement, 8 parts of clay ceramsite, 4 parts of fly ash, 2 parts of water, and 6 parts of water by weight. The concrete slag aggregate in the step 1 is specifically the aggregate for preparing unburned bricks obtained after crushing and screening of discarded concrete blocks, and the main components are cement stone, sand, and gravel. The building blocks and other building slag aggregates in the step 1 are specifically discarded sintered blocks, autoclaved blocks, and discarded prefabricated mortars. Aggregates used for brick making after treatment, the components contain silicate minerals. The fly ash in the step 1 can be replaced with blast furnace slag powder, and the water reducer can use a polycarboxylic acid-based water reducer instead of a traditional naphthalene-based water reducer;

[0045] Step 2: Crushing and screening of concrete slag aggregates. First, put the concrete slag aggregates into a jaw crusher, turn on the crusher for coarse crushing, and crush the concrete slag aggregates to a particle size of 28 mm. Then, transfer the coarsely crushed concrete slag aggregates to a cone crusher for medium crushing, and further reduce their particle size to 6 mm. Finally, use a vibrating screen to finely screen the medium-crushed concrete slag aggregates to screen out concrete slag aggregate particles with a particle size of 3 mm, so that they meet the particle size requirements for preparing unburned bricks. In the step 2, for building blocks and slag aggregates, an impact crusher can be used instead of a hammer crusher for crushing;

[0046] Step 3: Block and slag aggregate processing. Clean the blocks and other slag aggregates thoroughly, and carefully remove the wood, plastic, and metal impurities mixed in them. A combination of manual selection and mechanical screening can be used to ensure that the impurities are completely removed. Then, put the cleaned blocks and other slag aggregates into a hammer crusher, start the crusher to crush the blocks and other slag aggregates into fine particles, and then screen the crushed blocks and other slag aggregates through a vibrating screen, and select particles with a particle size of 3mm to meet the requirements of subsequent production;

[0047] Step 4: Screening and soaking the clay pellets. Use a sieve to screen out the clay pellets with a particle size of 5 mm. Then, put the screened clay pellets into a container filled with water and soak them for 6 hours to ensure that the clay pellets fully absorb water.

[0048] Step 5: Dry mix the raw materials. Add the processed concrete slag aggregate, building blocks and other construction slag aggregate, cement, clay ceramsite and fly ash into the forced mixer in sequence. Turn on the forced mixer, set the mixing speed and time, and mix at a speed of 100 revolutions per minute for 4 minutes to fully mix the various raw materials and achieve a dry-mixed uniform state.

[0049] Step 6: Prepare the water reducer solution. Pour an appropriate amount of water into a mixing container, then add the water reducer, turn on the stirrer, and stir at a speed of 120 revolutions per minute for 5 minutes to ensure that the water reducer is completely dissolved in the water to form a uniform water reducer solution.

[0050] Step 7: Prepare the slurry, slowly pour the prepared water reducing agent solution into the forced mixer, continue to stir the forced mixer, adjust the stirring speed to 150 revolutions per minute, stir for 6 minutes, so that the slurry has good fluidity and plasticity;

[0051] Step 8: Mold forming: quickly pour the stirred slurry into a mold of a predetermined shape and size, place the mold with the slurry on a vibrator, turn on the vibrator, and vibrate at a frequency of 3500 revolutions per minute for 4 minutes. At the same time, use a spatula to carefully trim the slurry on the edge and surface of the mold to ensure that the slurry is evenly distributed;

[0052] Step 9: Preliminary curing and demoulding. Move the formed bricks together with the molds to the curing room. Set the temperature of the curing room to 25°C and the relative humidity to 88%. Allow the bricks to cure in the curing room for 30 hours. Then use a special demoulding tool to carefully demould the bricks from the mold. In the curing stage of Steps 8 and 9, in addition to conventional natural curing combined with curing in a curing room, you can also explore the use of steam curing combined with natural curing for curing.

[0053] Step 10: Post-curing, keep the demoulding bricks in the curing room for 21 days to ensure that the environmental conditions in the curing room are stable so that the bricks can complete the subsequent curing process in a suitable environment. After curing, they can be stacked and stored. Clay ceramsite is used as aggregate and the formula is formulated according to product requirements to achieve lightweight and increase the thermal insulation and sound insulation properties of the product. The soaking pretreatment of clay ceramsite can ensure that its density is equivalent to that of other aggregates during the mixing and vibration process and that it is evenly distributed. In addition, the advance soaking pretreatment can effectively prevent the polymer slurry from flowing into the voids of the clay ceramsite, ensuring the stability of the product quality while providing moisture in the hydration reaction during the curing stage, forming self-curing and preventing the cracking of unfired bricks.

[0054] Embodiment three:

[0055] See also Figure 1 The present invention provides a method for preparing lightweight high-strength unfired bricks, comprising the following steps:

[0056] Step 1: weighing raw materials, using a high-precision electronic scale to accurately weigh the raw materials to ensure that the weight of each raw material is accurate, providing an accurate raw material ratio basis for the subsequent preparation process. The raw materials in the step 1 specifically include 30 parts of concrete slag aggregate, 30 parts of building blocks and other building slag aggregate, 20 parts of cement, 10 parts of clay ceramsite, 5 parts of fly ash, 3 parts of water reducer, and 10 parts of water by weight. The concrete slag aggregate in the step 1 is specifically the aggregate for preparing unburned bricks obtained after crushing and screening of discarded concrete blocks, and the main components are cement stone, sand, and gravel. The building blocks and other building slag aggregates in the step 1 are specifically discarded sintered blocks, autoclaved blocks, and discarded prefabricated mortar. Aggregates used for brick making after treatment, the components contain silicate minerals. The fly ash in the step 1 can be replaced with blast furnace slag powder, and the water reducer can use a polycarboxylic acid-based water reducer instead of a traditional naphthalene-based water reducer;

[0057] Step 2: Crushing and screening of concrete slag aggregates. First, put the concrete slag aggregates into a jaw crusher, turn on the crusher for coarse crushing, and crush the concrete slag aggregates to a particle size of 30 mm. Then, transfer the coarsely crushed concrete slag aggregates to a cone crusher for medium crushing, and further reduce their particle size to 10 mm. Finally, use a vibrating screen to finely screen the medium-crushed concrete slag aggregates to screen out concrete slag aggregate particles with a particle size of 5 mm, so that they meet the particle size requirements for preparing unburned bricks. In the step 2, for building blocks and slag aggregates, an impact crusher can be used instead of a hammer crusher for crushing;

[0058] Step 3: Block and slag aggregate processing, clean the blocks and other slag aggregates thoroughly, carefully remove the wood, plastic, and metal impurities mixed in them, and use a combination of manual selection and mechanical screening to ensure that the impurities are completely removed. Then, put the cleaned blocks and other slag aggregates into a hammer crusher, start the crusher to crush the blocks and other slag aggregates into fine particles, and then screen the crushed blocks and other slag aggregates through a vibrating screen, and select particles with a particle size of 5mm to meet the requirements of subsequent production;

[0059] Step 4: Clay pellets are screened and soaked. Use a sieve to screen out clay pellets with a particle size of 7 mm. Then, put the screened clay pellets into a container filled with water and soak them for 6 hours to ensure that the clay pellets fully absorb water.

[0060] Step 5: Dry mix the raw materials. Add the processed concrete slag aggregate, building blocks and other construction slag aggregate, cement, clay ceramsite and fly ash into the forced mixer in sequence. Turn on the forced mixer, set the mixing speed and time, and mix at a speed of 100 revolutions per minute for 4 minutes to fully mix the various raw materials and achieve a dry-mixed uniform state.

[0061] Step 6: Prepare the water reducer solution. Pour an appropriate amount of water into a mixing container, then add the water reducer, turn on the stirrer, and stir at a speed of 120 revolutions per minute for 5 minutes to ensure that the water reducer is completely dissolved in the water to form a uniform water reducer solution.

[0062] Step 7: Prepare the slurry, slowly pour the prepared water reducing agent solution into the forced mixer, continue to stir the forced mixer, adjust the stirring speed to 150 revolutions per minute, stir for 6 minutes, so that the slurry has good fluidity and plasticity;

[0063] Step 8: Mold forming: quickly pour the stirred slurry into a mold of a predetermined shape and size, place the mold with the slurry on a vibrator, turn on the vibrator, and vibrate at a frequency of 3500 revolutions per minute for 4 minutes. At the same time, use a spatula to carefully trim the slurry on the edge and surface of the mold to ensure that the slurry is evenly distributed;

[0064] Step 9: Preliminary curing and demoulding. Move the formed bricks together with the molds to the curing room. Set the temperature of the curing room to 30°C and the relative humidity to 90%. Allow the bricks to cure in the curing room for 36 hours. Then use a special demoulding tool to carefully demould the bricks from the mold. In the curing stage of Steps 8 and 9, in addition to conventional natural curing combined with curing in a curing room, you can also explore the use of steam curing combined with natural curing for curing.

[0065] Step 10: Post-curing, keep the demoulding bricks in the curing room for 21 days to ensure that the environmental conditions in the curing room are stable so that the bricks can complete the subsequent curing process in a suitable environment. After curing, they can be stacked and stored. Clay ceramsite is used as aggregate and the formula is formulated according to product requirements to achieve lightweight and increase the thermal insulation and sound insulation properties of the product. The soaking pretreatment of clay ceramsite can ensure that its density is equivalent to that of other aggregates during the mixing and vibration process and that it is evenly distributed. In addition, the advance soaking pretreatment can effectively prevent the polymer slurry from flowing into the voids of the clay ceramsite, ensuring the stability of the product quality while providing moisture in the hydration reaction during the curing stage, forming self-curing and preventing the cracking of unfired bricks.

[0066] Table 1: Comparison of raw material utilization:

[0067]

[0068]

[0069] Table 2: Physical performance comparison:

[0070]

[0071]

[0072] Table 3: Preparation process and cost comparison:

[0073]

[0074] The working principle of the present invention is as follows: the preparation method uses the concrete slag aggregate obtained by crushing and screening the waste concrete blocks, as well as the blocks formed by the treatment of the waste sintered blocks, autoclaved blocks, waste prefabricated mortar and other waste slag aggregates as the main raw materials. These construction wastes often cause serious pollution to the environment and occupy a large amount of precious land resources under the traditional treatment method. In the present invention, they become the core material for preparing unburned bricks, realizing the gorgeous transformation from waste to usable resources. For every 1 cubic meter of unburned bricks produced by the present invention, about 0.8 cubic meters of construction waste can be consumed. This large-scale construction waste disposal greatly reduces the environmental burden, not only reduces the pollution of soil and water bodies by the leachate that may be generated during the stacking of construction waste, but also avoids the secondary pollution caused by landfill or incineration of garbage, fully embodies the concept of green environmental protection and sustainable development, and is of great significance to promoting the development of circular economy.

[0075] Through precise raw material ratio and rigorous preparation process, the present invention successfully creates unburned bricks with excellent strength. The compressive strength can reach 30-40MPa, and the flexural strength can reach 4-6MPa. Such high strength performance enables the unburned bricks to withstand greater pressure and external force in construction projects, effectively ensuring the structural stability and safety of the buildings. Whether used to build multi-story residential buildings, commercial buildings or industrial plants, they can meet the strict requirements of wall materials for strength, laying a solid foundation for the long-term stability of building structures. Clay ceramsite is carefully added to the raw materials. This innovative measure gives the unburned bricks a good lightweight effect, and the brick density is generally controlled at 1400-1600kgm 3 Compared with traditional building bricks, the weight is significantly reduced. This lightweight feature brings many conveniences to construction. First, during transportation, it can reduce transportation costs and improve transportation efficiency; second, during construction, it can effectively reduce the labor intensity of construction workers and speed up construction progress; most importantly, after reducing the weight of the building, the requirements for the foundation of the building are relatively reduced, thereby reducing construction costs and improving the overall economic benefits of the construction project;

[0076] The unfired brick of the present invention also has excellent water resistance, and its water absorption rate is less than 10%, which means that when facing various humid environments or rain erosion, the brick body can effectively resist the penetration of water, and prevent the problems of brick body softening and strength reduction caused by long-term water absorption. Good water resistance not only prolongs the service life of the unfired brick itself, reduces the cost of repair and replacement due to brick body damage, but also ensures the dry environment inside the building, which is conducive to improving the overall durability and living comfort of the building. The preparation method of the present invention abandons the complicated and cumbersome process and adopts a simple and easy-to-operate process route. From the weighing and processing of raw materials to the mixing, molding and maintenance of each stage, each step is clear and definite, and workers do not need to have extremely high professional skills and complex operating experience. This simple and easy-to-use feature makes the production process more stable and controllable, reduces the risk of human error in the production process, and is also convenient for promotion and application in production sites of different sizes. Whether it is a large-scale industrial production line or a small local processing plant, efficient production can be easily achieved;

[0077] In the whole preparation process, the energy consumption is effectively reduced by optimizing the design of each link. For example, in the raw material processing stage, the type of crusher and crushing parameters are reasonably selected to avoid energy waste caused by excessive crushing; in the mixing process, the mixing speed and time are accurately controlled to ensure that the raw materials are fully mixed while reducing unnecessary energy consumption. In addition, in the curing stage, by reasonably setting the curing conditions, the curing efficiency is improved, the curing time is shortened, and the energy cost is reduced. This low-energy consumption preparation process not only conforms to the energy-saving and environmental protection concept advocated by the world, but also provides strong support for enterprises to reduce production costs. On the one hand, the large-scale use of construction waste as the main raw material greatly reduces the cost of raw materials. Compared with traditional building materials, construction waste is almost zero-cost, which greatly reduces the production cost. On the other hand, the simple preparation process and low energy consumption further compress the production cost. On the whole, the unburned brick of the present invention realizes effective cost control under the premise of ensuring product quality and performance, so that it has strong price competitiveness in the market. This cost-effective product can not only bring higher profit margins to construction companies, but also promote the construction industry to develop in a greener and more economical direction, with significant economic benefits and market potential.

[0078] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0079] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A method for preparing lightweight high-strength unfired bricks, characterized in that: The steps include: Step 1: Weighing raw materials: Use a high-precision electronic scale to accurately weigh the raw materials to ensure that the weight of each raw material is accurate, providing an accurate basis for the raw material ratio for the subsequent preparation process; Step 2: Crushing and screening of concrete slag aggregate. First, put the concrete slag aggregate into the jaw crusher, turn on the crusher for coarse crushing, and crush the concrete slag aggregate to a particle size of 25mm-30mm. Then, transfer the coarsely crushed concrete slag aggregate to the cone crusher for medium crushing, and further reduce its particle size to 5mm-10mm. Finally, use a vibrating screen to finely screen the medium-crushed concrete slag aggregate to select concrete slag aggregate particles with a particle size of 2mm-5mm, so that it meets the particle size requirements for preparing unburned bricks. Step 3: Block and slag aggregate processing, clean the blocks and other slag aggregates thoroughly, carefully remove the wood, plastic, and metal impurities mixed in them, and use a combination of manual selection and mechanical screening to ensure that the impurities are completely removed. Then, put the cleaned blocks and other slag aggregates into a hammer crusher, start the crusher to crush the blocks and other slag aggregates into fine particles, and then screen the crushed blocks and other slag aggregates through a vibrating screen, and select particles with a particle size between 2mm and 5mm to meet the requirements of subsequent production; Step 4: Clay pellets are screened and soaked. Use a sieve to screen out clay pellets with a particle size of 4mm-7mm. Then, put the screened clay pellets into a container filled with water and soak them for 6 hours to ensure that the clay pellets fully absorb water. Step 5: Dry mix the raw materials. Add the processed concrete slag aggregate, building blocks and other construction slag aggregate, cement, clay ceramsite and fly ash into the forced mixer in sequence. Turn on the forced mixer, set the mixing speed and time, and mix at a speed of 100 revolutions per minute for 4 minutes to fully mix the various raw materials and achieve a dry-mixed uniform state. Step 6: Prepare the water reducer solution. Pour an appropriate amount of water into a mixing container, then add the water reducer, turn on the stirrer, and stir at a speed of 120 revolutions per minute for 5 minutes to ensure that the water reducer is completely dissolved in the water to form a uniform water reducer solution. Step 7: Prepare the slurry, slowly pour the prepared water reducing agent solution into the forced mixer, continue to stir the forced mixer, adjust the stirring speed to 150 revolutions per minute, stir for 6 minutes, so that the slurry has good fluidity and plasticity; Step 8: Mold forming: quickly pour the stirred slurry into a mold of a predetermined shape and size, place the mold with the slurry on a vibrator, turn on the vibrator, and vibrate at a frequency of 3500 revolutions per minute for 4 minutes. At the same time, use a spatula to carefully trim the slurry on the edge and surface of the mold to ensure that the slurry is evenly distributed; Step 9: Pre-curing and demoulding. Move the formed bricks together with the mold to the curing room. Set the temperature of the curing room to 20℃-30℃ and the relative humidity to 85%-90%. Let the bricks cure in the curing room for 24-36 hours. Then use a special demoulding tool to carefully demould the bricks from the mold. Step 10: Post-curing: Place the demoulding bricks in the curing room for 21 days to ensure that the environmental conditions in the curing room are stable. The bricks can complete the subsequent curing process in a suitable environment and can be stacked and stored after curing.

2. The method for preparing a lightweight high-strength unburned brick according to claim 1, characterized in that: The raw materials in step 1 specifically include 20-30 parts by weight of concrete slag aggregate, 20-30 parts of building blocks and other slag aggregates, 10-20 parts of cement, 6-10 parts of clay ceramsite, 1-5 parts of fly ash, 1-3 parts of water reducer, and 5-10 parts of water.

3. The method for preparing a lightweight high-strength unburned brick according to claim 2, characterized in that: The concrete slag aggregate in step 1 is specifically the aggregate for preparing unburned bricks obtained after crushing and screening of waste concrete blocks, and its main components are cement stone, sand and gravel.

4. The method for preparing a lightweight high-strength unburned brick according to claim 3, characterized in that: The building blocks and other construction slag aggregates in step 1 are specifically discarded sintered building blocks, autoclaved building blocks, and discarded prefabricated mortar aggregates used for brick making after being processed, and contain silicate minerals.

5. The method for preparing a lightweight high-strength unburned brick according to claim 4, characterized in that: In the step, fly ash can be replaced with blast furnace slag powder, and the water reducing agent can use a polycarboxylic acid-based water reducing agent to replace the traditional naphthalene-based water reducing agent.

6. The method for preparing a lightweight high-strength unburned brick according to claim 5, characterized in that: In the step 2, for the building blocks and slag aggregates, an impact crusher can be used instead of a hammer crusher for crushing.

7. The method for preparing a lightweight high-strength unburned brick according to claim 6, characterized in that: During the curing stage in step eight and step nine, in addition to conventional natural curing combined with curing in a curing room, a curing method combining steam curing and natural curing can also be explored.

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