A device and method for synergistically strengthening wet grinding and carbonization of regenerated micro powder

Abstract

This invention provides an apparatus and method for synergistic enhancement of wet grinding and carbonization of regenerated micropowder, relating to the field of efficient resource utilization of construction solid waste. It solves the problem that existing technologies struggle to achieve in-situ synergistic coupling of mechanical activation and carbonization reactions, resulting in limited enhancement effects. The apparatus for synergistic enhancement of wet grinding and carbonization of regenerated micropowder includes a first driving component and a grinding assembly driven by the first driving component. It also includes an air intake assembly connected to the grinding assembly, a solid-liquid separation device disposed below the grinding assembly, and a drying chamber disposed below the solid-liquid separation device. The first driving component drives the grinding assembly to grind a suspended slurry, while the air intake assembly introduces carbon dioxide into the grinding assembly for synergistic enhancement. The ground and enhanced slurry is introduced into the solid-liquid separation device to remove free water, obtaining wet regenerated micropowder. The wet regenerated micropowder enters the drying chamber for drying to obtain enhanced regenerated micropowder.

Description

Technical Field

[0001] This invention relates to the field of efficient utilization technology of construction solid waste resources, and in particular to an apparatus and method for synergistic enhancement of wet grinding and carbonization of recycled micro powder. Background Technology

[0002] With the accelerating urbanization process in my country, the total amount of construction waste generated from building demolition, road renovation, and new construction projects continues to rise. During the crushing, screening, and recycled aggregate preparation of construction waste, a large amount of recycled micro-powder with a particle size of less than 0.15 mm is inevitably produced. This type of micro-powder mainly consists of incompletely hydrated cement stone, fine crushed aggregate powder, some inert minerals, and a small amount of impurities. It possesses a certain potential pozzolanic activity and, theoretically, can be used as a mineral admixture in concrete and mortar for resource utilization. However, existing recycled micro-powders generally suffer from poor particle morphology, a dense inert surface layer, high internal porosity, and blocked active sites. These problems directly lead to high water demand, poor fluidity, low early strength, and insufficient cementitious activity during application, making it difficult to achieve high-volume replacement of cement.

[0003] Currently, the enhancement treatment of regenerated micro powder mainly falls into two technical routes: mechanical grinding activation and carbonization modification. Mechanical grinding activation can break particles, remove the surface inert layer, and increase the specific surface area through impact, shearing, and friction, thereby improving the activity of micro powder; however, traditional dry grinding is prone to problems such as particle agglomeration, excessive temperature rise, and activity decay. Carbonization modification can utilize carbon dioxide to react with calcium hydroxide in micro powder to generate calcium carbonate to fill pores, but traditional carbonization has high mass transfer resistance, slow reaction, poor uniformity, and is often carried out in steps with grinding, resulting in a long process and low efficiency.

[0004] Existing technologies struggle to achieve in-situ synergistic coupling of mechanical activation and carbonization reactions, resulting in limited enhancement effects. Therefore, developing an integrated device and method capable of simultaneously completing wet grinding and carbonization is of significant engineering value for improving the quality of recycled micronized powder and promoting the high-value utilization of all components of construction waste. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide an apparatus and method for synergistic enhancement of wet grinding and carbonization of regenerated micro powder that can solve or at least alleviate the above-mentioned problems. It solves the problems of low activation efficiency, insufficient carbonization, lengthy step-by-step process, and poor synergy of existing regenerated micro powder, and can realize simultaneous grinding activation and carbonization densification, in-situ coupling, and mutual promotion. It significantly improves the mass transfer efficiency of carbon dioxide and the carbonization rate, greatly enhances the activity and density of regenerated micro powder, simplifies the process, reduces energy consumption, and is suitable for efficient industrial production.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution: In a first aspect, embodiments of the present invention provide an apparatus for the synergistic enhancement of wet grinding and carbonization of regenerated micropowder, comprising a first driving member, a grinding assembly driven by the first driving member, an air intake assembly connected to the grinding assembly, a solid-liquid separation device disposed below the grinding assembly, and a drying chamber disposed below the solid-liquid separation device; the first driving member drives the grinding assembly to grind a suspended slurry, while the air intake assembly introduces carbon dioxide into the grinding assembly for synergistic enhancement; the ground and enhanced slurry is introduced into the solid-liquid separation device to remove free water, obtaining wet regenerated micropowder; the wet regenerated micropowder enters the drying chamber for drying to obtain enhanced regenerated micropowder. The present invention integrates wet grinding and carbonization synergistic enhancement of regenerated micropowder into one device, achieving simultaneous grinding activation and carbonization densification, significantly improving the mass transfer efficiency and carbonization rate of carbon dioxide, greatly enhancing the activity and density of the regenerated micropowder, and simplifying the process.

[0007] Optionally, the grinding assembly includes a housing and a grinding barrel rotatably mounted within the housing. The grinding barrel has a double-layer jacket structure, including an outer grinding barrel layer rotatably mounted within the housing and an inner grinding barrel layer sleeved within the outer grinding barrel layer. An annular cooling jacket is formed between the outer and inner grinding barrel layers. Coolant flows through the grinding cavity formed by the annular cooling jacket and the inner grinding barrel layer for heat exchange. By exchanging heat through the grinding cavity formed by the annular cooling jacket and the inner grinding barrel layer, precise temperature control during the grinding process can be achieved, effectively avoiding particle agglomeration and activity decay caused by temperature rise, thereby ensuring stable performance and uniform quality of the regenerated micro powder.

[0008] Optionally, the grinding barrel is provided with an inlet and outlet, which are sealed by a sealing cover; the sealing cover is provided with an exhaust assembly.

[0009] Optionally, the exhaust assembly includes an exhaust port on the sealing cover and an inverted cap disposed outside the exhaust port; the opening of the inverted cap faces downward, forming a bent gas flow channel between it and the exhaust port base on the sealing cover. Gas generated during the grinding process enters the gas flow channel through the exhaust port and is then discharged, thereby achieving pressure balance within the cavity; simultaneously, the inverted cap, by altering the gas flow path and forming a shielding structure, prevents slurry from overflowing with the airflow, thus effectively preventing slurry splashing.

[0010] Optionally, after the synergistic strengthening of grinding and carbonization is completed, the grinding barrel is rotated by the first driving component, causing the inlet and outlet to rotate to the lower discharge position. Subsequently, an external flow guiding component is installed between the inlet and outlet and the solid-liquid separation device to guide the slurry after synergistic strengthening of grinding and carbonization into the solid-liquid separation device. The flow guiding component, together with the inlet and outlet and the solid-liquid separation device, forms a continuous and sealed flow path, allowing the slurry to be stably transported under gravity, thereby effectively preventing slurry splashing and leakage.

[0011] Optionally, the solid-liquid separation device includes a second driving member and a rotating screen cylinder driven by the second driving member; the upper end of the rotating screen cylinder is provided with a feed inlet, the side of the rotating screen cylinder is provided with a liquid outlet, and the lower end of the rotating screen cylinder is provided with a solid outlet.

[0012] Optionally, the air intake assembly includes a gas cylinder, an air intake pipe, and a connecting assembly; the air intake pipe connects the gas cylinder and the grinding barrel; the connecting assembly is installed at the end of the grinding barrel away from the first driving member, and the end of the air intake pipe away from the gas cylinder is installed on the connecting assembly.

[0013] Optionally, the connecting assembly includes a connecting flange, a seal, and an air inlet duct; the air inlet duct is fixedly connected to the housing via the connecting flange, and a seal is provided at the connection between the connecting flange and the housing; one end of the air inlet duct extends into the grinding chamber formed in the inner layer of the grinding barrel, forming an air inlet duct; a gas distributor is provided at the end of the air inlet duct. Carbon dioxide gas is released into the suspended slurry in the form of microbubbles through the gas distributor, thereby increasing the gas-liquid contact area and enhancing mass transfer efficiency.

[0014] Secondly, embodiments of the present invention provide a method for synergistic enhancement of regenerated micro powder through wet grinding and carbonization, using the aforementioned apparatus for synergistic enhancement of regenerated micro powder through wet grinding and carbonization, comprising the following steps: S1. Prepare a suspension slurry by mixing recycled construction waste powder with water at a liquid-solid ratio of 3:1-10:1. S2. Feeding and sealing the grinding barrel: Add the suspension slurry and grinding balls into the grinding barrel and seal the grinding barrel. S3. Perform wet grinding and carbonization synergistic strengthening treatment. Start the first drive unit to drive the grinding barrel to rotate at a speed of 200-400 r / min. At the same time, introduce carbon dioxide gas with a flow rate of 0.5-5.0 L / min into the grinding barrel and continue to treat for 10-40 min. S4. Introduce the ground and strengthened slurry into the solid-liquid separation device; S5. Solid-liquid separation treatment is carried out. After the slurry after grinding and strengthening enters the solid-liquid separation device, it runs at a speed of 1500-3000 r / min for 5-15 min under the action of a rotating screen cylinder. The solid particles and liquid are separated by centrifugation to obtain wet regenerated micro powder. S6. Perform low-temperature drying treatment: send the wet regenerated micro powder into the drying box and perform low-temperature drying treatment at 60-80 ℃ until a constant weight is reached, and finally obtain a high-density, low-water-requirement enhanced regenerated micro powder product.

[0015] Optionally, in step S3, the first drive unit is activated to rotate the grinding barrel at 300 r / min; at the same time, the air intake component is turned on to continuously introduce carbon dioxide at a flow rate of 2.0 L / min; the internal temperature of the grinding chamber of the grinding barrel is stably controlled at 25 ℃ by the coolant in the cooling jacket; and the synergistic strengthening treatment is carried out for 30 min.

[0016] Compared with the prior art, the present invention has at least the following beneficial effects: 1. The apparatus for synergistic enhancement of wet grinding and carbonization of regenerated micro powder provided by the present invention can realize in-situ synchronous coupling enhancement of wet grinding and carbon dioxide carbonization reaction. The grinding action breaks the inert layer on the surface of the regenerated micro powder particles and exposes the active sites. At the same time, the calcium carbonate product generated by the carbonization reaction fills the internal pores and interface structure of the particles in situ. The two promote each other, thereby significantly improving the enhancement effect.

[0017] 2. By exchanging heat through the grinding chamber formed by the annular cooling jacket and the inner layer of the grinding barrel, the temperature of the grinding process can be precisely controlled, which can effectively avoid particle agglomeration and activity decay caused by temperature rise, thereby ensuring stable performance and uniform quality of the regenerated micro powder.

[0018] 3. In this invention, the flow guiding component, together with the inlet / outlet and the solid-liquid separation device, forms a continuous and closed flow guiding path, which enables the slurry to be transported stably under the action of gravity, thereby effectively preventing slurry splashing and leakage, and improving the safety and reliability of the device operation.

[0019] 4. In this invention, carbon dioxide is introduced through the air intake component. Under wet grinding conditions, carbon dioxide gas is introduced and the gas is uniformly dispersed in the slurry in the form of microbubbles through the gas distribution head. This effectively increases the gas-liquid contact area, reduces mass transfer resistance, and improves the reaction rate, thereby achieving efficient and uniform carbonization reaction and significantly improving the density and reactivity of the regenerated micro powder.

[0020] 5. In this invention, the gas generated during the grinding process enters the gas flow channel through the exhaust hole and is then discharged, thereby achieving pressure balance within the cavity; at the same time, the inverted cap changes the gas flow path and forms a shielding structure to prevent the slurry from overflowing with the airflow, thereby effectively preventing slurry splashing. Attached Figure Description

[0021] Figure 1 A schematic diagram of a device for the synergistic enhancement of wet grinding and carbonization of regenerated micropowder according to an embodiment of the present invention is shown, wherein some components are omitted.

[0022] Figure 2 A schematic diagram of some components of a device for synergistic enhancement of regenerated micro-powder through wet grinding and carbonization is shown.

[0023] Figure 3 A schematic diagram of the sealing cap is shown, illustrating the gas flow path.

[0024] Figure 4 A cross-sectional schematic diagram of the grinding barrel is shown.

[0025] Figure 5 A cross-sectional schematic diagram of the carbon dioxide intake assembly is shown, along with enlarged views of some components.

[0026] Figure 6 A schematic diagram of the flow guiding and discharge assembly is shown.

[0027] Figure 7 A schematic diagram of a solid-liquid separation device is shown, with some components omitted.

[0028] Explanation of reference numerals in the attached drawings: 1-First driving component; 2-First rotating shaft; 3-Housing shell; 4-Inner layer of grinding barrel; 5-Outer layer of grinding barrel; 6-Cooling water inlet; 7-Cooling water outlet; 8-Inlet / outlet; 9-Sealing cover; 10-Air inlet pipe; 11-Gas cylinder; 12-Grinding ball; 13-Inlet; 14-Solid-liquid separation device; 15-Rotating screen cylinder; 16-Drying box; 17-Finished product collection port; 18-Bearing; 19-Air outlet; 20-Inverted cap; 21-Gas flow channel; 22-Air outlet base; 23-Connecting flange; 24-Fasting bolt; 25-Air distribution hole; 26-Sealing component; 27-Air inlet duct; 28-Air distribution head; 29-Flow guide inlet; 30-Flow guide transition component; 31-Connecting sleeve; 32-Slurry flow direction; 33-Liquid outlet; 34-Second rotating shaft; 35-Solid outlet; 36-Second driving component. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0030] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0031] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0032] In this invention, terms such as "upper," "lower," "left," "right," "front," "back," "vertical," "horizontal," "side," and "bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only to facilitate the description of the structural relationships of the various components or elements of this invention and do not specifically refer to any component or element in this invention. They should not be construed as limiting the invention.

[0033] In this invention, terms such as "fixed connection," "connected," and "linked" should be interpreted broadly, indicating a fixed connection, an integral connection, or a detachable connection; a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can determine the specific meaning of these terms in this invention based on the specific circumstances, and they should not be construed as limitations on the invention.

[0034] Example 1 like Figure 1 As shown, an embodiment of the present invention provides an apparatus for the synergistic enhancement of wet grinding and carbonization of regenerated micropowder, comprising a first driving component 1, a grinding assembly, an air inlet assembly, a solid-liquid separation device 14, and a drying chamber 16. The first driving component 1 drives the grinding assembly to grind the suspended slurry, while the air inlet assembly simultaneously introduces carbon dioxide into the grinding assembly for synergistic enhancement. The ground and enhanced slurry is then introduced into the solid-liquid separation device 14 to remove free water, yielding wet regenerated micropowder. The wet regenerated micropowder enters the drying chamber 16 for drying to obtain enhanced regenerated micropowder. Preferably, the first driving component 1, the grinding assembly, the air inlet assembly, the solid-liquid separation device 14, and the drying chamber 16 are all mounted on a support. The first driving component 1 is a drive motor, which drives the grinding assembly to perform the grinding operation via a first rotating shaft 2.

[0035] Also refer to Figure 1 and Figure 2The grinding assembly includes a housing 3 and a grinding barrel rotatably mounted within the housing 3. Preferably, the housing 3 is a fixed structure used to support the first rotating shaft 2 and the grinding barrel. More preferably, both ends of the housing 3 are supported on brackets. The first rotating shaft 2 passes through the housing 3, and its two ends are supported by bearings 18 and mounted in bearing seats. Preferably, the first rotating shaft 2 is connected to the first driving member 1 via a coupling, and under the drive of the first driving member 1, it drives the grinding barrel to rotate stably around its axis, thereby ensuring smooth operation of the device and reducing vibration.

[0036] The grinding barrel has a double-layer jacketed structure, including an outer grinding barrel layer 5 rotatably mounted in the housing 3, and an inner grinding barrel layer 4 sleeved within the outer grinding barrel layer 5. The inner grinding barrel layer 4 forms a grinding chamber for containing the regenerated micro-powder suspension slurry and the grinding balls 12. Preferably, the grinding balls 12 are spherical grinding media that can move freely within the grinding chamber, with a diameter of 10-60 mm. (See also...) Figure 4 An annular cooling jacket is formed between the outer layer 5 and the inner layer 4 of the grinding barrel. Cooling water enters the space between the outer layer 5 and the inner layer 4 (jacket) through the cooling water inlet 6, forming a cooling water layer distributed along the axial and circumferential directions of the barrel. This layer exchanges heat with the grinding chamber and is discharged through the cooling water outlet 7 during use, thus stabilizing the internal temperature of the grinding chamber at 20-35℃ and preventing excessive temperature rise during grinding, which could lead to particle agglomeration and activity reduction. (See also...) Figure 3 The grinding barrel has inlet and outlet ports 8, which are sealed by a sealing cover 9. Preferably, the sealing cover 9 is equipped with an exhaust assembly for releasing gas during carbonization and maintaining stable internal pressure while preventing slurry overflow. The exhaust assembly includes an outlet hole 19 on the sealing cover 9 and an inverted cap 20 disposed outside the outlet hole 19. Preferably, the outlet hole 19 penetrates the sealing cover 9 and communicates with the grinding chamber. The sealing cover 9 is equipped with an outlet hole base 22 corresponding to the outlet hole 19. Preferably, the outlet hole base 22 is integral with the sealing cover 9. The inverted cap 20 is installed on the outlet hole base 22. The opening of the inverted cap 20 faces downward, forming a bent gas flow channel 21 between it and the outlet hole base 22 on the sealing cover 9. Gas generated during grinding enters the gas flow channel 21 through the outlet hole 19 and is then discharged, thereby achieving pressure balance within the chamber. The inverted cap 20 effectively prevents slurry splashing by altering the gas flow path and forming a shielding structure, thus preventing slurry from overflowing with the airflow. Preferably, the gas flow channel 21 includes a first channel located at the center of the inverted cap 20 and a second channel located outside the first channel, with the top of the second channel positioned above the first channel. The gas flowing through the first channel has its flow path altered by the gas flowing through the second channel, forming a shield and preventing slurry from overflowing with the airflow.

[0037] The grinding barrel is fixedly connected to the first rotating shaft 2 and rotates at a speed of 200-400 r / min under the action of the first driving component 1. In conjunction with the grinding balls 12 in the grinding chamber, impact, shearing and friction are generated during the rotation to continuously grind the regenerated micro powder particles, thereby breaking the inert layer on the particle surface, refining the particles and exposing active sites, providing a reaction interface for the carbonization reaction. At the same time, the air intake component introduces carbon dioxide into the grinding chamber.

[0038] Also refer to Figure 1 and Figure 5 The air intake assembly includes a gas cylinder 11, an air intake pipe 10, and a connecting assembly. Preferably, the gas cylinder 11 contains carbon dioxide. The air intake pipe 10 connects the gas cylinder 11 and the grinding barrel. The connecting assembly is installed at the end of the grinding barrel away from the first driving member 1, and the end of the air intake pipe 10 away from the gas cylinder 11 is installed on the connecting assembly. The connecting assembly includes a connecting flange 23, a sealing element 26, and an air intake conduit 27. The air intake pipe 10 is fixedly connected to the housing 3 via the connecting flange 23, and a sealing element 26 is provided at the connection between the connecting flange 23 and the housing 3 to achieve sealing during gas delivery. Preferably, the sealing element 26 is a sealing ring. One end of the air intake pipe 10 passes through the housing 3 and extends into the grinding cavity formed by the inner layer 4 of the grinding barrel. The section of the air intake pipe located inside the grinding cavity constitutes the air intake conduit 27. An air distribution head 28 is provided at the end of the air intake conduit 27, and the air distribution head 28 has multiple air distribution holes 25. Preferably, multiple air distribution holes 25 are evenly spaced along the circumference of the air distribution head 28. More preferably, multiple air distribution holes 25 are also provided on the end face of the air distribution head 28 away from the air inlet duct 27. Through the multiple air distribution holes 25 in various directions on the air distribution head 28, carbon dioxide can be uniformly dispersed and delivered into the grinding chamber.

[0039] Optionally, the gas distribution head 28 is provided with multiple gas distribution channels extending axially along the air inlet duct. Carbon dioxide enters the gas distribution head 28 through the air inlet duct 27 and is evenly distributed and delivered to the grinding chamber through the multiple gas distribution channels. Preferably, the gas distribution head 28 is rotatably mounted on the air inlet duct 27. The multiple gas distribution channels are evenly spaced along the circumference of the gas distribution head. The circumferential side of the gas distribution head 28 is provided with teeth, and a gear engaging with the teeth is installed on the first rotating shaft 2 at a position corresponding to the teeth. When the first rotating shaft 2 rotates, the gear and teeth drive the gas distribution head 28 to rotate, thereby causing the multiple gas distribution channels to deliver carbon dioxide to the grinding chamber in a rotating manner. This effectively prevents solid particles from depositing in the grinding chamber and promotes sufficient contact between carbon dioxide bubbles and the suspended slurry.

[0040] Through the gas distribution head, carbon dioxide gas is released into the suspended slurry in the form of microbubbles via the gas distribution channel, thereby increasing the gas-liquid contact area and improving mass transfer efficiency. After the synergistic enhancement of grinding and carbonization is completed, the grinding barrel is rotated by the first drive component 1, causing the inlet / outlet 8 to rotate to the lower discharge position; subsequently, an external flow guide component is installed between the inlet / outlet 8 and the solid-liquid separation device 14, guiding the slurry enhanced by the synergistic grinding and carbonization into the solid-liquid separation device 14.

[0041] Also refer to Figure 6 The external flow guiding assembly includes a flow guiding inlet 29, a flow guiding transition piece 30, and a connecting sleeve 31. The flow guiding inlet 29 is detachably connected to the inlet / outlet 8 and is used to receive the slurry. The flow guiding transition piece 30 is used to adjust the slurry flow direction 32 and reduce impact. Preferably, the flow guiding transition piece 30 is a curved or inclined flow guiding channel. One end of the connecting sleeve 31 is connected to the flow guiding transition piece 30, and the other end is sealed to the solid-liquid separation device 14. Preferably, the connecting sleeve 31 is a flexible connecting sleeve. Under the action of gravity, the slurry sequentially enters the solid-liquid separation device 14 through the flow guiding inlet 29, the flow guiding transition piece 30, and the connecting sleeve 31, forming a continuous closed conveying channel, thereby effectively preventing slurry splashing and leakage.

[0042] Also refer to Figure 7 The solid-liquid separation device 14 includes a second driving member 36 and a rotating screen cylinder 15 driven by the second driving member 36. Preferably, the second driving member 36 is a drive motor. The upper end of the rotating screen cylinder 15 has a feed inlet 13. The side of the rotating screen cylinder 15 has a liquid outlet 33. The lower end of the rotating screen cylinder 15 has a solid outlet 35. The second driving member 36 drives the rotating screen cylinder 15 to rotate via a second rotating shaft 34. The rotating screen cylinder 15 is a cylindrical screening structure with multiple screen holes on its wall. After the slurry enters the rotating screen cylinder 15, centrifugal force is generated under the action of rotation. The liquid is thrown out through the screen holes and discharged from the liquid outlet 33 under the action of centrifugal force. The upper part of the solid outlet 35 has an opening and closing structure. During the solid-liquid separation process, the solid outlet 35 remains closed; after screening is completed, the opening and closing structure is opened to allow the solid particles (wet regenerated micro powder) to move along the inner wall of the screen cylinder and be discharged from the solid outlet 35, thereby achieving solid-liquid separation. Preferably, the rotating screen cylinder 15 rotates at a speed of 1500-3000 r / min, and the processing time is 5-15 min. The wet regenerated micro powder enters the drying chamber 16 for drying to obtain enhanced regenerated micro powder. Preferably, the drying chamber 16 is located below the solid-liquid separation device 14. The wet regenerated micro powder is fed into the drying chamber 16 and subjected to low-temperature drying treatment at 60-80 ℃ until a constant weight is reached. Then, the high-density, high-activity enhanced regenerated micro powder product is output through the finished product collection port 17.

[0043] Example 2 This invention also provides a method for synergistic enhancement of regenerated micro powder through wet grinding and carbonization, comprising the following steps: S1. Preparation of the suspension slurry. The recycled construction waste powder is mixed with water at a liquid-to-solid ratio of 3:1 to 10:1. Mechanical stirring is used to form a uniform and stable suspension slurry, ensuring thorough dispersion of the recycled powder particles and preventing agglomeration or sedimentation. Preferably, 5 kg of recycled construction waste powder is mixed with water at a liquid-to-solid ratio of 5:1 to form a uniform, sediment-free suspension slurry.

[0044] S2. Feeding and sealing the grinding barrel. The suspended slurry and grinding balls 12 are added into the grinding chamber formed by the inner layer 4 of the grinding barrel through the inlet / outlet 8. The sealing cover 9 is installed and tightened with bolts to form a sealed connection structure for the grinding chamber. At the same time, the gas is released in a controlled manner through the exhaust component set on the sealing cover 9, thereby maintaining the pressure balance inside the chamber while ensuring the airtightness, and providing a stable and controlled atmosphere environment for the subsequent carbonization reaction. Preferably, the slurry and 20 grinding balls with a diameter of 20mm are added into the inner grinding chamber of the double-layer jacketed grinding barrel, the sealing cover is closed, and it is evenly tightened with 6 fixing screws to ensure that the device is airtight.

[0045] S3. Perform synergistic strengthening treatment of wet grinding and carbonization. Start the first drive unit 1, which drives the grinding barrel to rotate at 200-400 r / min via the first rotating shaft 2. Simultaneously, carbon dioxide gas at a flow rate of 0.5-5.0 L / min is introduced into the grinding chamber through the air inlet pipe 10, and the treatment continues for 10-40 min. Preferably, start the first drive unit 1 to rotate the grinding barrel at 300 r / min; simultaneously, open the air inlet assembly to continuously introduce carbon dioxide at a flow rate of 2.0 L / min; and stabilize the internal temperature of the grinding chamber at 25 ℃ using cooling water in the cooling jacket; perform synergistic strengthening treatment for 30 min.

[0046] Under the action of rotation, the grinding ball 12 impacts, shears and rubs the regenerated micro powder particles, breaking the inert layer on the particle surface and exposing the internal active sites; at the same time, carbon dioxide dissolves in the slurry to form carbonic acid components, which react with the exposed active substances in situ to generate calcium carbonate products and fill the internal pores and interface structure of the particles, thereby realizing the in situ synchronous coupling and strengthening of wet grinding activation and carbonization densification.

[0047] S4. The ground and strengthened slurry is introduced into the solid-liquid separation device 14. After the synergistic strengthening treatment is completed, the first drive component 1 is controlled to make the grinding barrel continue to rotate, so that the inlet and outlet 8 rotates to the lower discharge position; then, the guide component is installed between the inlet and outlet 8 and the inlet 13 of the solid-liquid separation device 14.

[0048] Under the influence of gravity, the slurry enters the guide transition piece 30 through the guide inlet 29 and is then transported to the solid-liquid separation device 14 via the connecting sleeve 31, forming a continuous and closed guide path, thereby achieving stable slurry transport and preventing splashing and leakage.

[0049] S5. Solid-liquid separation treatment is performed. After the slurry enters the solid-liquid separation device 14, it runs at a speed of 1500-3000 r / min for 5-15 min under the action of the rotating screen cylinder 15. The solid particles and liquid are separated by centrifugation to obtain wet regenerated micro powder. Preferably, the enhanced slurry is introduced into a centrifuge and centrifuged at 2000 r / min for 6 min to remove free water and obtain wet regenerated micro powder.

[0050] S6. Perform low-temperature drying treatment. The wet regenerated micro powder is fed into drying oven 16 and dried at 60-80 ℃ until constant weight is achieved, ultimately obtaining a high-density, low-water-requirement reinforced regenerated micro powder product. Preferably, the wet micro powder is fed into the drying oven and dried at 70 ℃ to constant weight to obtain high-density reinforced regenerated micro powder.

[0051] In addition, the method of synergistic strengthening through wet grinding and carbonation of recycled micropowder also includes: S7, conducting concrete performance tests. Preferably, C30 concrete specimens are prepared by replacing an equal amount of cement with 30% of the reinforced recycled micropowder and curing according to standard. The 28-day compressive strength was measured to be 38.6 MPa.

[0052] Comparative Example 1 (Unreinforced regenerated micro powder) Using the same recycled micropowder processed with a non-inventory apparatus and method for wet grinding and carbonation synergistic strengthening of recycled micropowder, concrete specimens were prepared by replacing cement at a 30% admixture ratio under the same mix proportion and curing conditions. The 28-day compressive strength was measured to be 30.2 MPa.

[0053] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An apparatus for synergistic enhancement of regenerated micro-powder through wet grinding and carbonization, comprising a first driving member and a grinding assembly driven by the first driving member, characterized in that, It also includes an air intake assembly connected to the grinding assembly, a solid-liquid separation device disposed below the grinding assembly, and a drying oven disposed below the solid-liquid separation device; The first driving component drives the grinding assembly to grind the suspended slurry. At the same time, the air intake component introduces carbon dioxide into the grinding assembly for synergistic enhancement. The ground and enhanced slurry is introduced into the solid-liquid separation device to remove free water, resulting in wet regenerated micro powder. The wet regenerated micro powder enters the drying oven for drying to obtain enhanced regenerated micro powder.

2. The apparatus for synergistic enhancement of wet grinding and carbonization of regenerated micro-powder according to claim 1, characterized in that, The grinding assembly includes a housing and a grinding barrel rotatably mounted in the housing; the grinding barrel has a double-layer jacket structure, including an outer grinding barrel layer rotatably mounted in the housing and an inner grinding barrel layer sleeved in the outer grinding barrel layer; an annular cooling jacket is formed between the outer grinding barrel layer and the inner grinding barrel layer. The coolant flows through the annular cooling jacket and exchanges heat with the grinding chamber formed by the inner layer of the grinding barrel.

3. The apparatus for synergistic enhancement of wet grinding and carbonization of regenerated micro-powder according to claim 2, characterized in that, The grinding barrel has an inlet and outlet, which are sealed by a sealing cover; the sealing cover is equipped with an exhaust assembly.

4. The apparatus for synergistic enhancement of wet grinding and carbonization of regenerated micro-powder according to claim 3, characterized in that, The exhaust assembly includes an exhaust port on the sealing cover and an inverted cap disposed outside the exhaust port; the opening of the inverted cap faces downward and forms a bent gas flow channel with the exhaust port base on the sealing cover.

5. The apparatus for synergistic enhancement of wet grinding and carbonization of regenerated micro-powder according to claim 3, characterized in that, After the grinding and carbonization synergistic enhancement is completed, the grinding barrel is rotated by the first drive component, so that the inlet and outlet are rotated to the lower discharge position; then, the external flow guide component is installed between the inlet and outlet and the solid-liquid separation device to introduce the slurry after grinding and carbonization synergistic enhancement into the solid-liquid separation device.

6. The apparatus for synergistic enhancement of wet grinding and carbonization of regenerated micro-powder according to claim 5, characterized in that, The solid-liquid separation device includes a second driving component and a rotating screen cylinder driven by the second driving component; the upper end of the rotating screen cylinder is provided with a feed inlet, the side of the rotating screen cylinder is provided with a liquid outlet, and the lower end of the rotating screen cylinder is provided with a solid outlet.

7. The apparatus for synergistic enhancement of wet grinding and carbonization of regenerated micro-powder according to any one of claims 2 to 6, characterized in that, The air intake assembly includes a gas cylinder, an air intake pipe, and a connecting assembly; the air intake pipe connects the gas cylinder and the grinding barrel; the connecting assembly is installed at the end of the grinding barrel away from the first drive component, and the end of the air intake pipe away from the gas cylinder is installed on the connecting assembly.

8. The apparatus for synergistic enhancement of wet grinding and carbonization of regenerated micro-powder according to claim 7, characterized in that, The connecting assembly includes a connecting flange, a seal, and an air intake duct; the air intake duct is fixedly connected to the housing through the connecting flange, and a seal is provided at the connection between the connecting flange and the housing; one end of the air intake duct extends into the grinding chamber formed in the inner layer of the grinding barrel to form an air intake duct; an air distribution head is provided at the end of the air intake duct.

9. A method for synergistic enhancement of regenerated micro powder through wet grinding and carbonization, characterized in that, An apparatus employing the synergistic enhancement of wet grinding and carbonization of regenerated micro-powder according to any one of claims 1 to 8, comprising the following steps: S1. Prepare a suspension slurry by mixing recycled construction waste powder with water at a liquid-solid ratio of 3:1-10:

1. S2. Feeding and sealing the grinding barrel: Add the suspension slurry and grinding balls into the grinding barrel and seal the grinding barrel. S3. Perform wet grinding and carbonization synergistic strengthening treatment. Start the first drive unit to drive the grinding barrel to rotate at a speed of 200-400 r / min. At the same time, introduce carbon dioxide gas with a flow rate of 0.5-5.0 L / min into the grinding barrel and continue to treat for 10-40 min. S4. Introduce the ground and strengthened slurry into the solid-liquid separation device; S5. Solid-liquid separation treatment is carried out. After the slurry after grinding and strengthening enters the solid-liquid separation device, it runs at a speed of 1500-3000 r / min for 5-15 min under the action of a rotating screen cylinder. The solid particles and liquid are separated by centrifugation to obtain wet regenerated micro powder. S6. Perform low-temperature drying treatment: send the wet regenerated micro powder into the drying box and perform low-temperature drying treatment at 60-80 ℃ until a constant weight is reached, and finally obtain a high-density, low-water-requirement enhanced regenerated micro powder product.

10. The method for synergistic enhancement of regenerated micro-powder through wet grinding and carbonization according to claim 9, characterized in that, In step S3, the first drive unit is started to rotate the grinding barrel at 300 r / min; at the same time, the air intake component is turned on to continuously introduce carbon dioxide at a flow rate of 2.0 L / min; the internal temperature of the grinding chamber of the grinding barrel is stably controlled at 25 ℃ by the coolant in the cooling jacket; and the synergistic strengthening treatment is carried out for 30 min.

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