Resource utilization method for building construction waste

Abstract

The invention discloses a resource utilization method for building construction waste, and relates to the technical field of building construction. The method comprises the following steps: step a, pretreatment: carrying out multi-stage sorting on the construction waste to remove impurities, and carrying out primary crushing on inorganic components to obtain a primary crushed material with the particle size range of 60-120mm; b, split-flow treatment is conducted, specifically, the primary crushed material is divided into two parts, and the two parts enter a brick making raw material preparation branch and a recycled aggregate preparation branch respectively to be subjected to parallel treatment; and step c, material collaboration. According to the invention, active components of wastes are activated through microbial pretreatment, and a biological gelling agent is combined, so that the internal binding power and durability of the brick body are remarkably enhanced; the recycled aggregate is subjected to intelligent grading and differential surface treatment, aggregate grading is optimized, and the strength of the aggregate and the interface performance of the aggregate and cement paste are improved, so that the workability and strength of concrete are guaranteed, and the quality of recycled products is improved.

Description

Technical Field

[0001] This invention relates to the field of building construction technology, and in particular to a method for the resource utilization of building construction waste. Background Technology

[0002] In the field of construction waste management, the resource utilization of waste is crucial, as it relates to both environmental protection and the sustainable use of resources. Traditional methods for the resource utilization of construction waste have long been used in this field, and to some extent, they can process some waste and transform it into usable materials. However, with the development of the construction industry and the increasing demands for environmental protection and resource utilization, traditional methods are gradually becoming insufficient to meet practical needs.

[0003] From the perspective of product performance, bricks made by traditional methods lack sufficient strength and durability. This is because the lack of effective activation of the active components of waste and suitable cementitious materials results in insufficient internal bonding strength of the bricks. For recycled aggregate concrete, traditional methods fail to scientifically grade and specifically treat the recycled aggregates, leading to unreasonable aggregate gradation, poor aggregate strength and interfacial performance with cement paste, and consequently, difficulty in ensuring the workability and strength of the concrete. From the perspective of resource utilization, traditional methods often employ a single treatment approach with a lack of coordination among the various treatment stages, failing to fully utilize the various components in the waste, resulting in low resource utilization rates. Moreover, traditional methods do not form a systematic closed-loop collaborative system, the process logic is not clear enough, and there are significant limitations in practical applications, making them difficult to implement and promote.

[0004] To address these issues, we provide a method for the resource utilization of construction waste. Summary of the Invention

[0005] The purpose of this invention is to provide a method for the resource utilization of construction waste. Through the combination of material co-processing and intelligent control mechanisms, it solves the problems of insufficient strength and durability of the bricks produced, poor performance of recycled aggregate concrete, low resource utilization rate, and poor system synergy in the prior art.

[0006] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution: This invention relates to a method for the resource utilization of construction waste, comprising the following steps: Step a: Pretreatment: The construction waste is subjected to multi-stage sorting (manual sorting + airflow separation) to remove impurities (including flexible materials, magnetic impurities, and light particles), and the inorganic components are subjected to primary crushing to obtain primary crushed material with a particle size range of 60-120mm; Step b: Diversion treatment: The primary crushed material is divided into two parts, which are respectively fed into a brick-making raw material preparation branch and a recycled aggregate preparation branch for parallel processing; Step c: Material coordination: The excess fine particles generated in the brick-making raw material preparation branch are added as micro-aggregates to the recycled aggregate preparation branch, and the... The excess fine powder produced after grading in the recycled aggregate preparation branch is added as an active component to the brick-making raw material preparation branch. Ultrasonic dispersion technology is used to improve the mixing uniformity during the material synergy process. Step d: Intelligent control: Based on the real-time results of intelligent particle size classification in the recycled aggregate preparation branch, combined with the monitoring data of online moisture content sensor and aggregate strength tester, the proportion of primary crushed material diverted to the brick-making raw material preparation branch and the recycled aggregate preparation branch, as well as the construction mix ratio of recycled aggregate concrete, are dynamically adjusted. Step e: Product preparation: Brick products are prepared using the brick-making raw materials, and recycled aggregate concrete is prepared using the treated recycled aggregate.

[0007] The present invention is further configured such that the brick-making raw material preparation branch includes: microwave pretreatment of primary crushed material (power 300-500W, treatment time 5-8min), followed by microbial fermentation pretreatment using a composite strain of Streptococcus thermophilus and Bacillus subtilis, and then mixing the pretreated material with a bio-gelatinizer to obtain brick-making raw material; the recycled aggregate preparation branch includes: secondary crushing, screening and intelligent particle size classification of the second part of primary crushed material to obtain recycled aggregate with two or more different particle size ranges; and surface strengthening treatment of the recycled aggregate with different particle size ranges respectively adapted to their particle size.

[0008] The present invention is further configured such that the strain used in the microbial fermentation pretreatment is Bacillus, and the pretreatment conditions are: temperature 30-35℃, relative humidity 60%-70%, and treatment time 3-5 days.

[0009] The present invention is further configured such that the biogelatinizer comprises the metabolic products of the microorganism and nanocellulose, and the amount added is 5%-10% of the dry basis mass of the material after microbial fermentation pretreatment.

[0010] The present invention is further configured such that the intelligent particle size classification is achieved by using a laser scattering particle size analyzer and a near-infrared spectral sorter together, and the recycled aggregate is divided into three main particle size ranges of 4-9mm, 11-22mm and 23-42mm after classification.

[0011] The present invention is further configured such that the surface strengthening treatment adapted to the particle size specifically comprises: For recycled aggregates with a particle size of no more than 10 mm, surface roughening treatment is performed using plasma surface etching technology; For recycled aggregates with a particle size of not less than 20 mm, a strengthening liquid is applied by impregnation or spraying to perform surface reinforcement treatment. The strengthening liquid contains a titanium ester coupling agent and a metakaolin composite reinforcing material.

[0012] The present invention is further configured such that the material after microbial fermentation pretreatment is dried and sieved, and the fine particles passing through the 0.8mm sieve are used as micro-aggregates and are added to the recycled aggregate preparation branch at a ratio of 2%-6% of the total mass of the recycled aggregate. The fine powder with a particle size of less than 4.5 mm produced after intelligent particle size classification is used as an active component and is incorporated into the mixing stage of the brick-making raw material preparation branch at a ratio of 7%-18% of the total dry weight of the brick-making raw materials.

[0013] The present invention is further configured such that the preparation of brick products includes: pressing the brick-making raw materials into brick blanks, and then placing the brick blanks in an environment with a temperature of 222-28℃ and a relative humidity of 85%-92% for curing for 8-16 days, and then using infrared drying (temperature of 60-80℃, time of 1-2h) for strengthening treatment in the later stage of curing.

[0014] The present invention is further configured such that the raw materials for preparing recycled aggregate concrete are proportioned by mass as follows: 1 part cement, 2.8-3.2 parts recycled aggregate after surface strengthening treatment and gradation, 0.48-0.52 parts water, 0.04-0.07 parts chemical admixture, and 0.1-0.2 parts mineral powder.

[0015] The present invention is further configured such that the particle size range of the primary crushed material is 50-100mm; after the second part of the primary crushed material is subjected to the secondary crushing, it is first subjected to high-pressure air washing and dust removal treatment, and then enters the intelligent particle size classification stage.

[0016] The present invention has the following beneficial effects: 1. This invention significantly enhances the internal bonding strength and durability of bricks by activating the active components of waste through microbial pretreatment and combining it with a bio-gelling agent; it also optimizes the aggregate gradation and improves the strength of the aggregate itself and the interfacial performance with cement paste by intelligent grading and differentiated surface treatment of recycled aggregates, thereby ensuring the workability and strength of concrete and improving the quality of resource-based products.

[0017] 2. The present invention features two parallel and coordinated pathways, which significantly improves the overall resource utilization rate and product value. At the same time, the constructed closed-loop coordinated system overcomes the limitations of single utilization technology. The process logic is clear and easy to implement and promote. This systematic treatment method meets the modern construction industry's demand for efficient, environmentally friendly, and sustainable waste resource utilization, and has high market competitiveness and application prospects. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0019] Figure 1 This is a flowchart of a method for the resource utilization of construction waste. Detailed Implementation

[0020] The technical solutions of the present invention will be described below with reference to the accompanying drawings. The described embodiments are only some embodiments of the present invention, and not all embodiments.

[0021] Example 1 Please refer to Figure 1 A method for resource utilization of construction waste includes the following steps: Step a: Pretreatment: The construction waste is sorted in multiple stages (manual sorting + airflow separation) to remove impurities (including flexible materials, magnetic impurities, and light particles), and the inorganic components are subjected to primary crushing to obtain primary crushed material with a particle size range of 60-120mm; Step b: Diversion treatment: The primary crushed material is divided into two parts and fed into a brick-making raw material preparation branch and a recycled aggregate preparation branch for parallel processing; Step c: Material synergy: The excess fine particles generated in the brick-making raw material preparation branch are added as micro-aggregates. Step d: Intelligent control: Based on the real-time results of intelligent particle size classification in the recycled aggregate preparation branch, combined with the monitoring data of online moisture content sensor and aggregate strength tester, dynamically adjust the ratio of primary crushed material diverted to the brick raw material preparation branch and the recycled aggregate preparation branch, as well as the construction mix ratio of recycled aggregate concrete; Step e: Product preparation: Use brick raw materials to prepare brick products, and use treated recycled aggregate to prepare recycled aggregate concrete.

[0022] Through a series of steps including pretreatment, diversion, material coordination, intelligent control, and product preparation, a complete and systematic processing flow has been constructed. This flow overcomes the shortcomings of traditional methods in terms of product performance, resource utilization, and system coordination, realizes the efficient resource utilization of waste, and improves the performance of brick products and recycled aggregate concrete, demonstrating strong innovation.

[0023] Example 2 The brick-making raw material preparation branch includes: microwave pretreatment of primary crushed material (power 300-500W, processing time 5-8min), followed by microbial fermentation pretreatment using a composite strain of Streptococcus thermophilus and Bacillus subtilis, and then mixing the pretreated material with a bio-gelatinizer to obtain brick-making raw material; the recycled aggregate preparation branch includes: secondary crushing, screening, and intelligent particle size classification of the second part of primary crushed material to obtain recycled aggregates with two or more different particle size ranges; and surface strengthening treatment of recycled aggregates with different particle size ranges adapted to their respective particle sizes.

[0024] The brick-making raw material preparation branch uses microbial fermentation pretreatment combined with bio-gelatinizer, which can effectively activate the active components of waste and enhance the internal bonding strength and durability of the brick. The recycled aggregate preparation branch optimizes the gradation of recycled aggregate and improves aggregate performance through secondary crushing, screening, intelligent particle size classification and surface strengthening treatment adapted to its particle size. Compared with the traditional single treatment method, it significantly improves product quality.

[0025] The microbial fermentation pretreatment uses Bacillus strains, and the pretreatment conditions are: temperature 30-35℃, relative humidity 60%-70%, and treatment time 3-5 days.

[0026] By specifying the use of Bacillus and the specific treatment conditions for microbial fermentation pretreatment, the stability and controllability of the microbial fermentation process are ensured, which helps to improve the consistency of pretreatment effects and thus ensure the stability of brick product performance.

[0027] Biogelling agents are composed of microbial metabolites and nanocellulose, and their addition amount is 5%-10% of the dry basis mass of the material after microbial fermentation pretreatment.

[0028] Bio-gelling agents contain microbial metabolites and have specified addition amounts, which further enhance the bonding performance of bricks, better ensure the durability of brick products, and improve the reliability of brick product quality.

[0029] Intelligent particle size classification is achieved by combining a laser scattering particle size analyzer with a near-infrared spectral sorter. After classification, the recycled aggregate is divided into three main particle size ranges: 4-9mm, 11-22mm, and 23-42mm.

[0030] Intelligent particle size classification is achieved by using an image recognition system and an online laser particle size analyzer, which clarifies the main particle size range of recycled aggregates. This makes the classification of recycled aggregates more accurate, which is conducive to subsequent targeted processing based on different particle sizes, optimizing the gradation of recycled aggregates, and improving the performance of recycled aggregate concrete.

[0031] The specific surface strengthening treatment adapted to its particle size is as follows: For recycled aggregates with a particle size of no more than 10 mm, surface roughening treatment is performed using plasma surface etching technology; For recycled aggregates with a particle size of not less than 20 mm, a strengthening liquid is applied by impregnation or spraying to perform surface reinforcement treatment. The strengthening liquid contains a titanium ester coupling agent and a metakaolin composite reinforcement material.

[0032] Different surface strengthening treatments are used for recycled aggregates of different particle sizes, taking into full account the influence of particle size on aggregate performance. This can more effectively improve the strength of the aggregate itself and the interfacial performance with cement paste, thereby improving the applicability of recycled aggregates and the performance of concrete.

[0033] The material after microbial fermentation pretreatment is dried and sieved. The fine particles that pass through the 0.8mm sieve are used as micro-aggregates and are mixed into the recycled aggregate at a ratio of 2%-6% of the total mass of recycled aggregate to prepare the branch. Fine powder with a particle size of less than 4.5 mm produced after intelligent particle size classification is used as an active component and is incorporated into the mixing stage of the brick raw material preparation branch at a ratio of 7%-18% of the total dry basis of the brick raw materials.

[0034] The sources and proportions of micro-aggregates and active components were clarified, enabling the rational and synergistic utilization of materials from the two branches, improving the overall resource utilization rate of waste, and enhancing resource utilization efficiency and product value.

[0035] The particle size range of the primary crushed material is 50-100mm; after secondary crushing, the second part of the primary crushed material undergoes high-pressure air washing and dust removal treatment before entering the intelligent particle size classification stage.

[0036] Clearly defining the particle size range of primary crushed material and the sequence of secondary crushing and intelligent particle size classification makes the entire processing technology clearer and more reasonable, which is beneficial to actual production operations.

[0037] Example 3 The preparation of brick products includes: pressing the brick raw materials into brick blanks, then placing the brick blanks in an environment with a temperature of 222-28℃ and a relative humidity of 85%-92% for curing for 8-16 days, and then using infrared drying (temperature 60-80℃, time 1-2h) for strengthening treatment in the later stage of curing.

[0038] The regulations specify the molding and curing conditions for preparing brick products, ensuring the standardization of the brick product production process and improving the stability and consistency of brick product quality.

[0039] The raw materials for preparing recycled aggregate concrete are proportioned by weight as follows: 1 part cement, 2.8-3.2 parts surface-strengthened and graded recycled aggregate, 0.48-0.52 parts water, 0.04-0.07 parts chemical admixture, and 0.1-0.2 parts mineral powder.

[0040] The material mass ratio for preparing recycled aggregate concrete is given, providing a clear standard for the preparation of recycled aggregate concrete, which helps to ensure the performance stability of recycled aggregate concrete and improves the controllability of concrete quality.

[0041] Example 4 Pre-treatment stage: Construction waste is sorted to remove impurities, and then the inorganic components are subjected to primary crushing to reduce the particle size of the waste, resulting in primary crushed material with a particle size range of 50-100mm, which is prepared for subsequent processing.

[0042] Diversion processing stage: The primary crushed material is divided into two parts and sent to the brick-making raw material preparation branch and the recycled aggregate preparation branch respectively. The two branches are processed in parallel to improve processing efficiency.

[0043] Material synergy stage: The excess fine particles generated from the brick raw material preparation branch are used as micro-aggregates and added to the recycled aggregate preparation branch at a ratio of 2%-6% of the total mass of recycled aggregates; the excess fine powder with a particle size of less than 5mm generated after grading in the recycled aggregate preparation branch is used as active components and added to the brick raw material preparation branch at a ratio of 5%-15% of the total dry basis mass of brick raw materials, so as to achieve efficient utilization of resources.

[0044] Intelligent control stage: The material in the recycled aggregate preparation branch is intelligently classified by an image recognition system and an online laser particle size analyzer. Based on the real-time classification results, the ratio of primary crushed material diverted to the brick raw material preparation branch and the recycled aggregate preparation branch, as well as the construction mix ratio of recycled aggregate concrete, are dynamically adjusted to optimize product performance.

[0045] Product preparation stage: In the brick-making raw material preparation branch, the first part of the primary crushed material is first subjected to microbial fermentation pretreatment (using Bacillus, treated for 3-5 days at a temperature of 30-35℃ and a relative humidity of 60%-70%). The pretreated material is dried and sieved, and mixed with a bio-gelling agent containing microbial metabolites at an addition amount of 5%-10% of its dry weight to obtain brick-making raw materials. The brick-making raw materials are pressed into brick blanks, and then the brick blanks are placed in an environment at a temperature of 20-25℃ and a relative humidity of 90%-95% for 7-14 days to produce brick products. In the recycled aggregate preparation branch, the primary crushed material from the second part undergoes secondary crushing. The crushed material then enters the intelligent particle size classification stage, dividing the recycled aggregate into three main particle size ranges: 5-10mm, 10-20mm, and 20-40mm. Surface strengthening treatments are then applied to the recycled aggregate in each particle size range (particles no larger than 10mm undergo physical and mechanical surface roughening, while particles no smaller than 20mm undergo surface strengthening treatment by impregnation or spraying with a strengthening liquid containing silane coupling agent and inorganic cementitious reinforcing material). The treated recycled aggregate is then used to prepare recycled aggregate concrete by mixing 1 part cement, 2.8-3.2 parts surface-strengthened and graded recycled aggregate, 0.48-0.52 parts water, 0.04-0.07 parts chemical admixtures, and 0.1-0.2 parts mineral powder by mass ratio.

[0046] Example 5 Pre-treatment: A batch of construction waste, including bricks, concrete blocks, and gravel, is selected and manually sorted to remove impurities such as wood and plastic. Then, a jaw crusher is used to perform primary crushing of the inorganic components, controlling the output particle size to 50-100mm, resulting in primary crushed material with a particle size range of 60-120mm.

[0047] Diversion processing: The primary crushed material is divided into two parts, which are then fed into the brick-making raw material preparation branch and the recycled aggregate preparation branch, respectively.

[0048] Material coordination: Brick-making raw material preparation branch: Primary crushed material undergoes microwave pretreatment (300-500W, 5-8 min), followed by microbial fermentation pretreatment using a composite strain of *Streptococcus thermophilus* and *Bacillus subtilis*, with *Bacillus subtilis* selected as the inoculum. Treatment is carried out for 4 days at 30℃ and 65% relative humidity. The pretreated material is dried and sieved; fine particles passing through a 0.8mm sieve are used as micro-aggregates for later use. Then, the pretreated material is mixed with a bio-gelatinizer at 8% of the dry weight of the pretreated material to obtain the brick-making raw material.

[0049] The recycled aggregate preparation branch: The primary crushed material from the second part undergoes secondary crushing using a cone crusher. It is then sieved using a vibrating screen, and intelligent particle size classification is performed using an image recognition system and an online laser particle size analyzer, separating the recycled aggregate into three main particle size ranges: 5-10mm, 10-20mm, and 20-40mm. For recycled aggregate with a particle size no greater than 10mm, a physical-mechanical surface roughening treatment is performed using a grinding device; for recycled aggregate with a particle size no less than 20mm, a surface strengthening treatment is performed by applying a strengthening liquid through impregnation. The strengthening liquid contains a composite reinforcing material of titanate coupling agent and metakaolin. The fine powder with a particle size less than 4.5mm produced after intelligent particle size classification is used as an active component for later use.

[0050] The micro-aggregates generated in the brick-making raw material preparation branch are added to the recycled aggregate preparation branch at a ratio of 3% of the total mass of recycled aggregates; the active components generated in the recycled aggregate preparation branch are added to the mixing stage of the brick-making raw material preparation branch at a ratio of 10% of the total dry basis mass of the brick-making raw materials.

[0051] Intelligent control: Real-time monitoring of the intelligent particle size classification results in the recycled aggregate preparation branch, and dynamic adjustment of the proportion of primary crushed material diverted to the brick-making raw material preparation branch and the recycled aggregate preparation branch, as well as the construction mix ratio of recycled aggregate concrete, based on the proportion of recycled aggregate in different particle size ranges. For example, if the proportion of recycled aggregate in the 5-10mm particle size range is high, the proportion of primary crushed material entering the brick-making raw material preparation branch is appropriately increased, and the proportion of each raw material in the recycled aggregate concrete is adjusted accordingly to ensure the performance of the recycled aggregate concrete.

[0052] Product preparation: Brick product preparation: The raw materials for brick making are pressed into brick blanks using a hydraulic brick machine. The brick blanks are then placed in a curing room with a temperature of 22℃ and a relative humidity of 92% for 10 days to obtain brick products.

[0053] Preparation of recycled aggregate concrete: Mix 1 part cement, 3 parts surface-strengthened and graded recycled aggregate, 0.5 parts water, and 0.05 parts chemical admixture by mass ratio, and prepare recycled aggregate concrete by uniform mixing.

[0054] Example 6 Pre-treatment: Another batch of construction waste is collected and impurities are removed by manual sorting using a conveyor belt. Then, an impact crusher is used to perform primary crushing of the inorganic components to obtain primary crushed material with a particle size of 50-100mm.

[0055] Diversion processing: The primary crushed material is distributed to the brick-making raw material preparation branch and the recycled aggregate preparation branch in a ratio of 6:4.

[0056] Material coordination: Brick-making raw material preparation branch: Primary crushed material undergoes microwave pretreatment (300-500W, 5-8 min), followed by microbial fermentation pretreatment using a composite strain of *Streptococcus thermophilus* and *Bacillus subtilis* at 32℃ and 60% relative humidity for 3 days using *Bacillus subtilis*. The pretreated material is dried and sieved, with fine particles retained as micro-aggregates. Next, the pretreated material is mixed with a bio-gelatinizer, added at 5% of the dry weight of the pretreated material.

[0057] The recycled aggregate preparation branch: The primary crushed material from the second part undergoes secondary crushing using a hammer crusher. It is then sieved through a drum screen and further classified using an online laser particle size analyzer, resulting in three particle size ranges: 5-10mm, 10-20mm, and 20-40mm. For recycled aggregate with a particle size no larger than 10mm, surface roughening is performed using a sandblasting machine; for recycled aggregate with a particle size no smaller than 20mm, surface reinforcement is achieved by applying a strengthening liquid through spraying. The fine powder produced after intelligent particle size classification is used as an active component.

[0058] Micro-aggregates from the brick-making raw material preparation branch are added to the recycled aggregate preparation branch at a ratio of 1% of the total mass of recycled aggregates; active components from the recycled aggregate preparation branch are added to the brick-making raw material preparation branch at a ratio of 5% of the total dry basis mass of the brick-making raw materials.

[0059] Intelligent control: Based on real-time data from intelligent particle size classification of recycled aggregates, the diversion ratio of primary crushed material and the mix proportion of recycled aggregate concrete are adjusted. If the content of recycled aggregate in the 10-20mm particle size range is found to be low, the amount of primary crushed material entering the brick-making raw material preparation branch is appropriately reduced, and the amount of each raw material in the recycled aggregate concrete is adjusted to ensure its performance stability.

[0060] Product preparation: Brick product preparation: The raw materials for brick making are pressed into brick blanks under a press. The brick blanks are then cured in an environment with a temperature of 20℃ and a relative humidity of 95% for 14 days to produce brick products.

[0061] Preparation of recycled aggregate concrete: Mix 1 part cement, 2.5 parts surface-strengthened and graded recycled aggregate, 0.45 parts water, and 0.03 parts chemical admixture to prepare recycled aggregate concrete.

[0062] The preferred embodiments of the present invention disclosed above are only for the purpose of illustrating the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation described herein. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can better understand and utilize the present invention.

Claims

1. A method for the resource utilization of construction waste, characterized in that: Includes the following steps: Step a: Pre-treatment: The construction waste is sorted in multiple stages to remove impurities, and the inorganic components are subjected to primary crushing to obtain primary crushed material with a particle size range of 60-120mm. Step b: Diversion processing: The primary crushed material is divided into two parts, which are then fed into the brick-making raw material preparation branch and the recycled aggregate preparation branch for parallel processing. Step c: Material Co-processing: The excess fine particles generated in the brick-making raw material preparation branch are added as micro-aggregates to the recycled aggregate preparation branch, and the excess fine powder generated after the grading of the recycled aggregate preparation branch is added as active components to the brick-making raw material preparation branch. Ultrasonic dispersion technology is used to improve the mixing uniformity during the material co-processing. Step d: Intelligent control: Based on the real-time results of intelligent particle size classification in the recycled aggregate preparation branch, combined with the monitoring data of online moisture content sensor and aggregate strength tester, dynamically adjust the proportion of primary crushed material diverted to the brick raw material preparation branch and the recycled aggregate preparation branch, as well as the construction mix ratio of recycled aggregate concrete. Step e: Product preparation: Brick products are prepared using the brick-making raw materials, and recycled aggregate concrete is prepared using the treated recycled aggregate.

2. The method for resource utilization of construction waste according to claim 1, characterized in that: The brick-making raw material preparation branch includes: microwave pretreatment of primary crushed material (power 300-500W, treatment time 5-8min), followed by microbial fermentation pretreatment using a composite strain of Streptococcus thermophilus and Bacillus subtilis, and then mixing the pretreated material with a bio-gelatinizer to obtain brick-making raw material; the recycled aggregate preparation branch includes: secondary crushing, screening, and intelligent particle size classification of the second part of primary crushed material to obtain recycled aggregate with two or more different particle size ranges; and surface strengthening treatment of the recycled aggregate with different particle size ranges according to their respective particle size ranges.

3. The method for resource utilization of construction waste according to claim 2, characterized in that: The microbial fermentation pretreatment uses Bacillus strains, and the pretreatment conditions are: temperature 30-35℃, relative humidity 60%-70%, and treatment time 3-5 days.

4. The method for resource utilization of construction waste according to claim 2, characterized in that: The biogelatinizer is composed of the metabolic products of the microorganisms and nanocellulose, and its addition amount is 5%-10% of the dry basis mass of the material after microbial fermentation pretreatment.

5. A method for resource utilization of construction waste according to claim 2, characterized in that: The intelligent particle size classification is achieved by using a laser scattering particle size analyzer and a near-infrared spectral sorter together. After classification, the recycled aggregate is divided into three main particle size ranges: 4-9mm, 11-22mm, and 23-42mm.

6. A method for resource utilization of construction waste according to claim 2, characterized in that: The surface strengthening treatment adapted to its particle size specifically includes: For recycled aggregates with a particle size of no more than 10 mm, surface roughening treatment is performed using plasma surface etching technology; For recycled aggregates with a particle size of not less than 20 mm, a strengthening liquid is applied by impregnation or spraying to perform surface reinforcement treatment. The strengthening liquid contains a titanium ester coupling agent and a metakaolin composite reinforcing material.

7. A method for resource utilization of construction waste according to claim 2, characterized in that: The material after microbial fermentation pretreatment is dried and sieved. Fine particles passing through a 0.8mm sieve are used as micro-aggregates and are added to the recycled aggregate preparation branch at a ratio of 2%-6% of the total mass of recycled aggregate. The fine powder with a particle size of less than 4.5 mm produced after intelligent particle size classification is used as an active component and is incorporated into the mixing stage of the brick-making raw material preparation branch at a ratio of 7%-18% of the total dry weight of the brick-making raw materials.

8. The method for resource utilization of construction waste according to claim 1, characterized in that: The preparation of brick products includes: pressing the brick-making raw materials into brick blanks, and then placing the brick blanks in an environment with a temperature of 222-28℃ and a relative humidity of 85%-92% for curing for 8-16 days. In the later stage of curing, infrared drying (temperature 60-80℃, time 1-2h) is used for strengthening treatment.

9. A method for resource utilization of construction waste according to claim 1, characterized in that: The raw materials for preparing recycled aggregate concrete are proportioned by weight as follows: 1 part cement, 2.8-3.2 parts surface-strengthened and graded recycled aggregate, 0.48-0.52 parts water, 0.04-0.07 parts chemical admixture, and 0.1-0.2 parts mineral powder.

10. A method for resource utilization of construction waste according to claim 2, characterized in that: The particle size range of the primary crushed material is 50-100mm; after the secondary crushing, the second part of the primary crushed material is first subjected to high-pressure air washing and dust removal treatment, and then enters the intelligent particle size classification stage.

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