Concrete recycled aggregate particle shaping and wet carbonization synergistic reinforcement device

Abstract

The utility model discloses a kind of concrete recycled aggregate particle shaping and wet carbonization synergistic reinforcement device, including multistage crushing shaping module and wet carbonization reinforcement module connected in turn along the direction of material flow, multistage crushing shaping module is constituted by primary jaw crusher cavity and secondary vortex shaping cavity, cavity is equipped with angle-adjustable cavity wall baffle and cavity bottom centrifugal impeller, remove needle flake particle by intergranular collision, and cooperate with vibrating screen system adjustment granularity distribution;Wet carbonization reinforcement module includes airtight reaction container, agitator, aggregate layering net and CO2 gas circulation system, CO2 is synergized by refining spray head and agitator, realizes carbonization reaction, forms dense CaCO3 layer, improves the compressive strength, impermeability and durability of aggregate.The utility model effectively combines crushing shaping and wet carbonization reinforcement technology, improves the comprehensive performance of recycled aggregate, provides efficient, low-cost solution for the resource processing of construction waste.

Description

Technical Field

[0001] This utility model relates to the field of resource utilization technology of construction solid waste, specifically to a device for synergistic strengthening of recycled concrete aggregate particles by integrating waste concrete crushing, shaping and wet carbonization strengthening. Background Technology

[0002] With the continuous acceleration of urbanization in my country, urban renewal and infrastructure construction have generated a large amount of construction waste, of which waste concrete accounts for the largest proportion. Traditional methods of disposing of waste concrete mainly involve landfilling or open dumping, which not only occupies a large amount of land resources but also causes serious environmental pollution and resource waste. Therefore, crushing and screening waste concrete into recycled aggregates for use in the production of new concrete products is one of the most effective ways to achieve the resource utilization of construction waste.

[0003] However, compared with natural aggregates, recycled aggregates obtained from the simple crushing of waste concrete have many performance defects: on the one hand, they have poor particle shape, a high content of needle-like and flaky particles, and generate a large number of micro-cracks during the crushing process, resulting in low bulk density, high porosity, high water absorption, and low crushing index; on the other hand, the surface of recycled aggregates is covered with a large amount of old cement mortar, which is the main reason for their performance degradation. These inherent defects severely restrict the application grade and added value of recycled aggregates, which can usually only be used in low-grade concrete or road base materials, greatly limiting the development of the construction waste recycling industry.

[0004] To improve the performance of recycled aggregates, researchers both domestically and internationally have proposed various strengthening methods, mainly including physical strengthening, chemical strengthening, and microbial mineralization strengthening. Physical strengthening (such as mechanical shaping) removes surface-adhered mortar and improves particle shape through inter-particle collisions and friction, but it is energy-intensive and prone to causing new micro-damage; chemical strengthening (such as acid immersion and polymer modification) can improve surface properties, but it is costly and may introduce harmful substances; microbial mineralization strengthening technology is still immature and difficult to apply on a large scale.

[0005] In recent years, carbonation strengthening technology has received widespread attention as an emerging green method. This technology utilizes CO2 to react with cement hydration products Ca(OH)2 and CSH gel to generate dense CaCO3, thereby sealing the pores and microcracks in recycled aggregates and improving their density and strength. In particular, the wet carbonation process, which involves carbonization in a slurry environment, has higher reaction efficiency and more significant strengthening effects. However, currently, this technology is mostly used as an independent post-processing step, often disconnected from crushing and shaping processes, failing to achieve a synergistic effect. Furthermore, it typically requires the preparation of fresh slurry as a carbon source, resulting in higher costs.

[0006] Therefore, there is an urgent need to develop an integrated processing device that can organically combine physical shaping with wet carbonization strengthening technology, and make full use of the waste slurry generated by concrete mixing plants as a carbonization medium. This will not only efficiently improve the performance of recycled aggregates, but also achieve "waste treatment with waste," reduce processing costs, and promote the high-value and large-scale development of construction waste resource utilization. Utility Model Content

[0007] The technical problem to be solved by this utility model is that, in the existing technology, the performance enhancement process of recycled aggregate has problems such as dispersed process, high energy consumption, high cost and failure to make full use of waste. This utility model provides an integrated, high-efficiency and low-cost concrete recycled aggregate particle shaping and wet carbonization synergistic enhancement device. It aims to significantly improve the comprehensive performance of recycled aggregate through the organic combination of physical shaping and chemical carbonization, and realize the synergistic resource utilization of waste concrete and waste slurry.

[0008] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A device for synergistic strengthening of recycled concrete aggregate particle shaping and wet carbonation includes a multi-stage crushing and shaping module and a wet carbonation strengthening module connected sequentially along the material flow direction. The multi-stage crushing and shaping module is used to crush construction waste and improve the particle shape of recycled aggregate, including a primary jaw crushing chamber and a secondary vortex shaping chamber. The discharge port of the primary jaw crushing chamber is connected to the inlet of the secondary vortex shaping chamber. The wet carbonation strengthening module is used to carbonize and cure the shaped recycled aggregate, including a sealed reaction vessel connected to a CO2 gas circulation system. A pressure detector and a pressure relief valve are installed at the top of the sealed reaction vessel, and a slurry discharge port is installed at the bottom of the side wall. The discharge port of the multi-stage crushing and shaping module is connected to the inlet of the wet carbonation strengthening module to realize continuous conveying of the shaped aggregate.

[0009] Furthermore, the primary jaw crushing chamber includes a fixed jaw plate, a movable jaw plate, an eccentric shaft, an adjustment mechanism, and a discharge hopper. The motor drives the eccentric shaft through a pulley to drive the movable jaw plate to perform periodic reciprocating motion. Through cooperation with the fixed jaw plate, the old cement concrete is crushed by compression. The compression gap is changed by the adjustment mechanism to initially control the particle size of the crushed product. The crushed recycled aggregate enters the secondary vortex shaping chamber through the discharge hopper.

[0010] Furthermore, the adjustment mechanism includes a push-pull plate and an axial guide assembly. The push-pull plate is fixed to the back of the fixed jaw plate, and the guide assembly limits the fixed jaw plate to slide only along the axial direction. The push-pull plate is driven by a screw, hydraulic cylinder or electric actuator to drive the fixed jaw plate to move axially, thereby adjusting the discharge port gap and controlling the particle size of the crushed product.

[0011] Furthermore, the secondary vortex shaping chamber includes a cylindrical cavity, an inlet, an outlet, an adjustable-angle cavity wall impact plate, a centrifugal impeller at the bottom of the cavity, and a shaping chamber shaft. The shaping chamber shaft is mounted on an external support and is used to drive and control the overall tilt angle of the cylindrical cavity. The adjustable-angle cavity wall impact plate is hinged to the inner wall of the cavity via the shaft and an adjusting rod, and its angle can be adjusted within the range of 30° to 60° to change the working conditions of a single collision. The centrifugal impeller at the bottom of the cavity is driven by a motor to rotate at high speed. Under the action of centrifugal force, the material collides and rubs against the adjustable-angle cavity wall impact plate. By adjusting the shaping chamber shaft, the working tilt angle of the cavity is changed, thereby controlling the axial flow speed and residence time of the material in the cavity. This works in conjunction with the angle adjustment of the adjustable-angle cavity wall impact plate to achieve the best particle shaping effect for different materials.

[0012] Furthermore, the multi-stage crushing and shaping module also includes a vibrating screening system for screening the material after processing in the secondary vortex shaping chamber to control the particle size distribution of the output aggregate. The vibrating screening system is connected to the discharge port of the secondary vortex shaping chamber. The vibrating screening system is equipped with three layers of screens with different apertures: the uppermost screen has an aperture of 20mm, the middle screen has an aperture of 10mm, and the bottom screen has an aperture of 5mm, which is used to control the particle size distribution of the output aggregate to a continuous gradation of 5-20mm. The inclination angle of the three layers of screens is 15°-25°, and a vibrating motor is configured to prevent aggregate accumulation and improve screening efficiency.

[0013] Furthermore, the sealed reaction vessel includes a cylindrical tank and a stirrer. The cylindrical tank has multiple layers of aggregate mesh inside to support the aggregate. The top of the cylindrical tank has a feed inlet and a pressure relief valve, and the bottom of the cylindrical tank has a drain outlet. The stirrer includes a variable frequency drive motor, a stirring shaft, and anchor-type stirring blades. The gap between the outer edge of the anchor-type stirring blades and the inner wall of the reaction vessel is 5mm to 5cm to maintain the uniformity of the suspension. The sealed reaction vessel is pre-filled with a waste cement slurry suspension recovered from a ready-mixed concrete plant, whose Ca... 2+ It has a concentration of 0.5 mol / L to 2 mol / L and is used as a calcium source for carbonization reactions.

[0014] Furthermore, the aggregate layering mesh is a three-layer stainless steel perforated mesh structure installed inside the sealed reaction vessel to support the recycled aggregate and arrange the aggregate in layers in the suspension. The layer spacing is 20cm to 50cm, and the mesh size of each aggregate support mesh is 5mm to 20mm.

[0015] Furthermore, the CO2 gas circulation system includes a CO2 gas source, a gas delivery pipeline, a micron-level atomizing nozzle located at the end of the pipeline, and a gas circulation device; the gas circulation device includes a vacuum pump, a gas purifier, and a recirculation pipeline for realizing the recovery and reuse of CO2 gas; the recirculation pipeline is equipped with a one-way valve to prevent CO2 backflow, and the gas purifier has a built-in desiccant to remove moisture from the circulating gas; the sealed reaction vessel is also equipped with a pressure sensor and a CO2 concentration sensor for real-time monitoring of the reaction environment.

[0016] Furthermore, the micron-level atomizing nozzles are located below the aggregate layering mesh and are evenly distributed along the circumference of the tank bottom, used to form microbubbles in the suspension to improve carbonation efficiency.

[0017] Furthermore, the inlets and outlets of the primary jaw crushing chamber, the secondary vortex shaping chamber, the vibrating screening system, and the sealed reaction vessel are rigidly connected in sequence to form an integrated closed production line.

[0018] In this invention, a hole can be drilled in the lid of the cylindrical tank as a feed / liquid inlet, or the entire lid can be used as a detachable feed / liquid inlet. The lid can be lifted when feeding and closed when reacting, with the same effect and reaction mechanism.

[0019] Compared with the prior art, the present invention has the following significant advantages: 1. Collaborative and efficient: By integrating multi-stage crushing and shaping with wet carbonization strengthening modules, continuous operation of five major processes of recycled aggregate from crushing, shaping, screening, carbonization to slurry recovery is realized, solving the problems of dispersed and inefficient traditional processes and greatly improving processing efficiency.

[0020] 2. Significant performance improvement: First, the vortex shaping effectively improves the aggregate particle shape and reduces the content of needle-like and flaky particles; then, wet carbonation is used to generate a dense calcium carbonate layer on the surface of the aggregate. The dual effects synergistically significantly improve the bulk density, crushing value and durability of recycled aggregate, making its performance close to that of natural aggregate.

[0021] 3. Waste-to-waste treatment with low cost: The innovative use of waste slurry from concrete mixing plants as a calcium source and medium for carbonation reaction eliminates the need to prepare fresh chemical solutions and consumes industrial CO2, achieving synergistic resource utilization of two types of waste and greatly reducing raw material and processing costs.

[0022] 4. Green and environmentally friendly: The entire process achieves 100% resource utilization of waste concrete and waste slurry, and seals in CO2 gas, reducing carbon emissions. Attached Figure Description

[0023] Figure 1This is a schematic diagram of the overall structure of this utility model; Figure 2 for Figure 1 Cross-sectional view; Figure 3 for Figure 1 Schematic diagram of the structure of a primary and intermediate jaw crusher; Figure 4 for Figure 1 Cross-sectional view of the secondary vortex shaping cavity; Figure 5 for Figure 1 Cross-sectional view of a closed reaction vessel for wet carbonization; In the diagram, 100 is the multi-stage crushing and shaping module, 110 is the primary jaw crushing chamber, 111 is the fixed jaw plate, 112 is the movable jaw plate, 113 is the eccentric shaft, 114 is the adjustment mechanism, and 115 is the discharge hopper; 120 is the secondary vortex shaping chamber, 121 is the cylindrical chamber, 122 is the feed inlet, 123 is the discharge outlet, 124 is the adjustable angle chamber wall impact plate, 125 is the centrifugal impeller at the bottom of the chamber, and 126 is the shaping chamber shaft. 130--Vibrating screening system, 200--Wet carbonization enhancement module, 210--Sealed reaction vessel, 211--Feed inlet, 212--Slurry drain, 213--Cylindrical tank, 214--Drive motor, 215--Agitator shaft, 216--Anchor-type agitator blades, 217---Aggregate stratification mesh, 218--Tank bottom inlet, 219--Micron-level atomizing nozzle, 220--CO2 concentration sensor, 221--Pressure relief valve. Detailed Implementation

[0024] The present invention will be further explained and described below with reference to the accompanying drawings and specific embodiments: Example: See Figure 1 and Figure 2 This embodiment provides a synergistic strengthening device for shaped and wet carbonation of recycled concrete aggregate particles, including a multi-stage crushing and shaping module 100 and a wet carbonation strengthening module 200 connected sequentially along the material flow direction. The multi-stage crushing and shaping module 100 is used to crush construction waste and improve the particle shape of recycled aggregate, including a primary jaw crushing chamber 110 and a secondary vortex shaping chamber 120. The discharge port of the primary jaw crushing chamber 110 is connected to the inlet of the secondary vortex shaping chamber 120. The wet carbonation strengthening module 200 is used to carbonize and cure the shaped recycled aggregate, including a closed reaction vessel 210. The closed reaction vessel 210 is connected to a CO2 gas circulation system. A pressure detector and a pressure relief valve 221 are installed at the top of the closed reaction vessel 210, and a slurry discharge port 212 is installed at the bottom of the side wall. The discharge port of the multi-stage crushing and shaping module 100 is connected to the inlet of the wet carbonation strengthening module 200 to realize the continuous conveying of the shaped aggregate.

[0025] See Figure 3 The primary jaw crushing chamber 110 includes a fixed jaw plate 111, a movable jaw plate 112, an eccentric shaft 113, an adjustment mechanism 114, and a discharge hopper 115. The motor drives the eccentric shaft 113 through a belt pulley to drive the movable jaw plate 112 to perform periodic reciprocating motion. Through cooperation with the fixed jaw plate 111, it achieves the extrusion crushing of old cement concrete. The extrusion gap is changed by the adjustment mechanism 114 to initially control the particle size of the crushed product. The crushed recycled aggregate enters the secondary vortex shaping chamber 120 through the discharge hopper.

[0026] The adjustment mechanism 114 includes a push-pull plate and an axial guide assembly (not shown in the figure). The push-pull plate is fixed to the back of the fixed jaw plate. The guide assembly limits the fixed jaw plate to slide only along the axial direction. The push-pull plate is driven by a screw, hydraulic cylinder or electric actuator to drive the fixed jaw plate to move axially, thereby adjusting the discharge port gap and controlling the particle size of the crushed product.

[0027] See Figure 4 The secondary vortex shaping 120 includes a cylindrical cavity 121, an inlet 122, an outlet 123, an adjustable-angle cavity wall impact plate 124, a cavity bottom centrifugal impeller 125, and a shaping cavity shaft 126. The shaping cavity shaft 126 is mounted on an external support and is used to drive and control the overall tilt angle of the cylindrical cavity 121. The adjustable-angle cavity wall impact plate 124 is hinged to the inner wall of the cavity via a shaft and an adjusting rod, and its angle can be adjusted within the range of 30° to 60° to change the working conditions of a single collision. The cavity bottom centrifugal impeller 125 is driven by a motor to rotate at high speed. Under the action of centrifugal force, the material collides and rubs against the adjustable-angle cavity wall impact plate 124. By adjusting the shaping cavity shaft 126, the working tilt angle of the cavity is changed, thereby controlling the axial flow speed and residence time of the material in the cavity. This works in conjunction with the angle adjustment of the adjustable-angle cavity wall impact plate 124 to achieve the best particle shaping effect for different materials.

[0028] See Figure 1 and Figure 2 The multi-stage crushing and shaping module 100 also includes a vibrating screening system 130, which is used to screen the material after it has been processed by the secondary vortex shaping chamber to control the particle size distribution of the output aggregate. The vibrating screening system 130 is connected to the discharge port of the secondary vortex shaping chamber 120. The vibrating screening system 130 is equipped with three layers of screens with different apertures. The uppermost screen has an aperture of 20mm, the middle screen has an aperture of 10mm, and the bottom screen has an aperture of 5mm. This is used to control the particle size distribution of the output aggregate to a continuous gradation of 5-20mm. The inclination angle of the three screens is 15°-25°, and a vibrating motor is configured to prevent aggregate accumulation and improve screening efficiency.

[0029] See Figure 5The sealed reaction vessel includes a cylindrical tank 213 and a stirrer. The cylindrical tank has a multi-layered aggregate mesh 217 inside to support the aggregate. A feed inlet 211 and a pressure relief valve 221 are located on the top cover of the cylindrical tank 213, and a slurry discharge outlet 212 is located at the bottom of the cylindrical tank 213. The stirrer includes a variable frequency drive motor 214, a stirring shaft 215, and anchor-type stirring blades 216. The gap between the outer edge of the anchor-type stirring blades 216 and the inner wall of the reaction vessel is 5mm to 5cm to maintain the uniformity of the suspension. The sealed reaction vessel 210 is pre-filled with a waste cement slurry suspension recovered from a ready-mixed concrete plant, whose Ca... 2+ It has a concentration of 0.5 mol / L to 2 mol / L and is used as a calcium source for carbonization reactions.

[0030] The aggregate layering mesh is a three-layer stainless steel perforated mesh structure installed inside the sealed reaction vessel 210. It is used to support recycled aggregate and arrange the aggregate in layers in the suspension. The layer spacing is 20cm to 50cm, and the mesh size of each aggregate support mesh is 5mm to 20mm.

[0031] The CO2 gas circulation system includes a CO2 gas source, a gas delivery pipeline, a micron-level atomizing nozzle 219 located at the end of the pipeline, and a gas circulation device. The gas circulation device includes a vacuum pump, a gas purifier, and a recirculation pipeline for recovering and reusing CO2 gas. A one-way valve is installed on the circulation pipeline to prevent CO2 backflow, and the gas purifier has a built-in desiccant to remove moisture from the circulating gas. A pressure sensor and a CO2 concentration sensor 220 are also installed on the sealed reaction vessel 210 for real-time monitoring of the reaction environment.

[0032] Micron-level atomizing nozzles 219 are located below aggregate layering mesh 217 and are evenly distributed along the circumference of the tank bottom to form microbubbles in the suspension to improve carbonation efficiency.

[0033] The inlets and outlets of the primary jaw crusher chamber 110, the secondary vortex shaping chamber 120, the vibrating screening system 130, and the sealed reaction vessel 210 are rigidly connected in sequence to form an integrated closed production line.

[0034] Application examples: See Figure 2 A device for synergistic strengthening of concrete recycled aggregate particle shaping and wet carbonization is provided with a multi-stage crushing and shaping module 100 and a wet carbonization strengthening module 200 in sequence along the material flow direction; the multi-stage crushing and shaping module 100 includes a primary jaw crushing chamber 110, a secondary vortex shaping chamber 120 and a vibrating screening system 130.

[0035] See Figure 3In the primary jaw crushing chamber 110, the fixed jaw plate 111 and the movable jaw plate 112 form a crushing chamber. The motor drives the eccentric shaft 113 through the belt pulley, so that the movable jaw plate makes periodic reciprocating motion to perform primary crushing of construction waste with a feed particle size ≤500 mm. The adjustment mechanism 114 includes a push-pull plate and an axial guide assembly (not shown in the figure). The push-pull plate is fixed to the back of the fixed jaw plate. The guide assembly limits the fixed jaw plate to slide only along the axial direction. The discharge port gap can be steplessly adjusted within the range of 5-80 mm. After primary crushing, the particle size is ≤80 mm. The crushed product enters the secondary vortex shaping chamber 120 through the discharge hopper 115.

[0036] See Figure 4 In the secondary vortex shaping chamber 120, a cylindrical cavity 121 has an inlet 122 at the top and an outlet 123 at the bottom. Four adjustable-angle impact plates 124 (adjustable range 30°-60°, accuracy ±1°) are evenly distributed on the cavity wall. A centrifugal impeller 125 (driven by a variable frequency motor, linear speed 25-35 m / s) is installed at the bottom of the cavity. The shaping chamber's rotating shaft 126 is mounted on an external support, allowing the cylindrical cavity to tilt within a 0°-15° range, macroscopically controlling the material residence time to 2-8 s. Under centrifugal force, the material collides with the impact plates at least twice at different angles, reducing the content of needle-like and flaky particles from 18% to ≤8%, resulting in a product particle size of 5-40 mm after shaping.

[0037] See Figure 2 The vibrating screening system 130 is vertically connected to the discharge port 123 of the secondary vortex shaping chamber. It is equipped with three layers of stainless steel screens (apertures of 20 mm, 10 mm, and 5 mm) with an inclination angle of 18° and a vibrating motor. The screening efficiency is ≥95%. 5-20 mm continuous graded aggregates enter the wet carbonization strengthening module, and >20 mm aggregates are returned to the secondary vortex shaping chamber for further crushing.

[0038] See Figure 5 In the closed reaction vessel 210, the cylindrical tank 213 is designed with a pressure of 0.3 MPa. The top is equipped with a feed inlet 211 and a pressure relief valve 221 (opening pressure 0.22 MPa), and the bottom is equipped with a slurry discharge outlet 212. Three layers of stainless steel aggregate mesh 217 (mesh size 5-20 mm, layer spacing 30 cm) are arranged axially at equal intervals inside the tank, alternating with the anchor-type stirring blades 216 to prevent short circuits between layers.

[0039] The variable frequency drive motor 214 (speed adjustable from 5 to 50 r / min) drives the anchor-type stirring blade 216 through the stirring shaft 215. The outer edge of the anchor-type stirring blade 216 is 3 cm away from the tank wall to keep the suspension uniform and not damage the carbonized layer on the surface of the aggregate.

[0040] Micron-level atomizing nozzles 219 are located below the aggregate layering mesh 217 and are evenly distributed along the circumference of the tank bottom. The nozzle orifice diameter is 100 μm and the outlet velocity is 25 m / s, forming microbubbles. The gas circulation device includes a vacuum pump, a gas purifier (with built-in desiccant) and a recirculation pipeline. A one-way valve is installed on the circulation pipeline to form a bottom-top-bottom circulation. The CO2 volume fraction is stabilized at 15-25%, and the pressure sensor and CO2 concentration sensor 220 monitor it in real time.

[0041] A waste cement slurry suspension recycled from a ready-mixed concrete plant is pre-placed in a closed reaction vessel 210 as a calcium source for the carbonation reaction. 2+ A concentration of 1.2 mol / L, pH ≥ 12, and a liquid-to-solid mass ratio of 1:2 are used to provide the Ca required for carbonization. 2+ It also consumes industrial CO2.

[0042] The results show: Carbonization temperature 45 ℃, pressure 0.15 MPa, time 2 h; A dense CaCO3 layer of 5-12 μm is formed on the surface of the aggregate, the crushing index is reduced from 26% to 18%, the water absorption rate is reduced by 40%, and the 28-day mortar strength ratio is ≥105%. Each ton of aggregate solidifies 22 kg of CO2, the system dust emission is ≤10 mg / m³, and wastewater discharge is zero. The primary jaw crusher chamber 110, the secondary vortex shaping chamber 120, the vibrating screening system 130, and the sealed reaction vessel 210 are sealed by flanges, and the whole system operates under negative pressure, forming an integrated closed production line.

[0043] The above embodiments and application examples are only used to illustrate this utility model and do not constitute a limitation thereof; any modifications, equivalent substitutions, or improvements made by those skilled in the art without departing from the spirit of this utility model shall fall within the protection scope of the claims of this utility model.

Claims

1. A device for synergistic strengthening of recycled concrete aggregate particles through shaping and wet carbonation, characterized in that: The system includes a multi-stage crushing and shaping module and a wet carbonization strengthening module connected sequentially along the material flow direction. The multi-stage crushing and shaping module is used to crush construction waste and improve the particle shape of recycled aggregate. It includes a primary jaw crushing chamber and a secondary vortex shaping chamber, with the discharge port of the primary jaw crushing chamber connected to the feed port of the secondary vortex shaping chamber. The wet carbonization strengthening module is used to carbonize and cure the shaped recycled aggregate. It includes a sealed reaction vessel connected to a CO2 gas circulation system. A pressure detector and a pressure relief valve are installed at the top of the sealed reaction vessel, and a slurry discharge port is installed at the bottom of the side wall. The discharge port of the multi-stage crushing and shaping module is connected to the feed port of the wet carbonization strengthening module to achieve continuous conveying of the shaped aggregate.

2. The synergistic strengthening device for granular shaping and wet carbonation of recycled concrete aggregates according to claim 1, characterized in that: The primary jaw crushing chamber includes a fixed jaw plate, a movable jaw plate, an eccentric shaft, an adjustment mechanism, and a discharge hopper. The motor drives the eccentric shaft through a belt pulley to make the movable jaw plate perform periodic reciprocating motion. Through cooperation with the fixed jaw plate, it achieves the extrusion crushing of old cement concrete. The extrusion gap is changed by the adjustment mechanism to initially control the particle size of the crushed product. The crushed recycled aggregate enters the secondary vortex shaping chamber through the discharge hopper.

3. The synergistic strengthening device for granular shaping and wet carbonation of recycled concrete aggregates according to claim 2, characterized in that: The adjustment mechanism includes a push-pull plate and an axial guide assembly. The push-pull plate is fixed to the back of the fixed jaw plate, and the guide assembly limits the fixed jaw plate to slide only along the axial direction. The push-pull plate is driven by a screw, hydraulic cylinder or electric actuator to drive the fixed jaw plate to move axially, thereby adjusting the discharge port gap and controlling the particle size of the crushed product.

4. The synergistic strengthening device for granular shaping and wet carbonation of recycled concrete aggregates according to claim 1, characterized in that: The secondary vortex shaping chamber includes a cylindrical cavity, an inlet, an outlet, an adjustable-angle cavity wall impact plate, a centrifugal impeller at the bottom of the cavity, and a shaping chamber shaft. The shaping chamber shaft is mounted on an external support and is used to drive and control the overall tilt angle of the cylindrical cavity. The adjustable-angle cavity wall impact plate is hinged to the inner wall of the cavity via the shaft and an adjusting rod, and its angle can be adjusted within the range of 30° to 60° to change the working conditions of a single collision. The centrifugal impeller at the bottom of the cavity is driven by a motor to rotate at high speed. Under the action of centrifugal force, the material collides and rubs against the adjustable-angle cavity wall impact plate. By adjusting the shaping chamber shaft, the working tilt angle of the cavity is changed, thereby controlling the axial flow speed and residence time of the material in the cavity. This works in conjunction with the angle adjustment of the adjustable-angle cavity wall impact plate to achieve the best particle shaping effect for different materials.

5. The synergistic strengthening device for granular shaping and wet carbonation of recycled concrete aggregates according to claim 1, characterized in that: The multi-stage crushing and shaping module also includes a vibrating screening system for screening the material after it has been processed by the two-stage vortex shaping chamber, in order to control the particle size distribution of the output aggregate. The vibrating screening system is connected to the discharge port of the two-stage vortex shaping chamber. The vibrating screening system is equipped with three layers of screens with different apertures: the uppermost screen has an aperture of 20mm, the middle screen has an aperture of 10mm, and the bottom screen has an aperture of 5mm, which is used to control the particle size distribution of the output aggregate to a continuous gradation of 5-20mm. The inclination angle of the three layers of screens is 15°-25°, and a vibrating motor is configured to prevent aggregate accumulation and improve screening efficiency.

6. The synergistic strengthening device for granular shaping and wet carbonation of recycled concrete aggregates according to claim 1, characterized in that: The sealed reaction vessel includes a cylindrical tank and a stirrer. The cylindrical tank has multiple layers of aggregate mesh inside to support the aggregate. The top of the cylindrical tank has a feed inlet and a pressure relief valve, and the bottom has a drain outlet. The stirrer includes a variable frequency drive motor, a stirring shaft, and anchor-type stirring blades. The outer edge of the anchor-type stirring blades has a gap of 5mm to 5cm with the inner wall of the reaction vessel to maintain the uniformity of the suspension. The sealed reaction vessel is pre-filled with a waste cement slurry suspension recycled from a ready-mixed concrete plant, whose Ca... 2+ It has a concentration of 0.5 mol / L to 2 mol / L and is used as a calcium source for carbonization reactions.

7. The synergistic strengthening device for granular shaping and wet carbonation of recycled concrete aggregates according to claim 6, characterized in that: The aggregate layering mesh is a three-layer stainless steel perforated mesh structure installed inside the sealed reaction vessel. It is used to support the recycled aggregate and arrange the aggregate in layers in the suspension. The layer spacing is 20cm to 50cm, and the mesh size of each aggregate support mesh is 5mm to 20mm.

8. The synergistic strengthening device for granular shaping and wet carbonation of recycled concrete aggregates according to claim 1, characterized in that: The CO2 gas circulation system includes a CO2 gas source, a gas delivery pipeline, a micron-level atomizing nozzle located at the end of the pipeline, and a gas circulation device. The gas circulation device includes a vacuum pump, a gas purifier, and a recirculation pipeline for recovering and reusing CO2 gas. The recirculation pipeline is equipped with a one-way valve to prevent CO2 backflow, and the gas purifier has a built-in desiccant to remove moisture from the circulating gas. The sealed reaction vessel is also equipped with a pressure sensor and a CO2 concentration sensor for real-time monitoring of the reaction environment.

9. The synergistic strengthening device for granular shaping and wet carbonation of recycled concrete aggregates according to claim 8, characterized in that: The micron-level atomizing nozzles are located below the aggregate layering mesh and are evenly distributed along the circumference of the tank bottom, used to form microbubbles in the suspension to improve carbonation efficiency.

10. The synergistic strengthening device for granular shaping and wet carbonation of recycled concrete aggregates according to claim 5, characterized in that: The inlets and outlets of the primary jaw crusher chamber, the secondary vortex shaping chamber, the vibrating screening system, and the sealed reaction vessel are rigidly connected in sequence to form an integrated closed production line.

Images