High-fluidity micro-expansion multi-solid-waste grouting repairing material and preparation process thereof

Abstract

This invention relates to the field of building materials technology, and more specifically, to a high-fluidity, micro-expansion multi-solid waste grouting repair material and its preparation process, comprising a cementitious material system, composite solid waste admixture, aggregate, water, and water-reducing agent, characterized in that it is composed of the following components by weight: 48-60 parts of the cementitious material system, which is compounded from 42.5 ordinary Portland cement, 42.5 composite Portland cement, and 42.5R rapid-hardening sulfoaluminate cement in a ratio of (20-60)%: (20-60)%: (5-15)%; 12-20 parts of the composite solid waste admixture, including... The material is composed of lithium slag powder, metakaolin, titanium slag powder, limestone powder, and steel slag powder, with a mass ratio of (20-40)%: (10-20)%: (17-25)%: (10-18)%: (10-23)%; 18-25 parts of aggregate, including continuously graded sand (0-4.75mm) composed of spherical steel slag sand and titanium slag aggregate; 17-23 parts of water; and 0.2-0.5 parts of water-reducing agent. This invention solves the problems of insufficient early strength, high cost, large loss of fluidity, and dependence on admixtures for expansion in existing grouting repair materials.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, and more specifically, to a high-fluidity, micro-expansion, multi-solid waste grouting repair material and its preparation process. Background Technology

[0002] In the field of building materials, traditional cement-based grouting materials are important repair and reinforcement materials. Their raw materials mainly rely on natural resources, such as cement, fly ash, silica fume and slag powder. However, the mining and utilization of these natural resources not only consume a large amount of non-renewable resources, but may also have a negative impact on the environment.

[0003] Meanwhile, with the implementation of the GB / T175-2023 standard for general-purpose Portland cement, the price of raw materials for ordinary Portland cement (PO cement) has increased, prompting the industry to seek more cost-effective alternatives. Against the backdrop of solid waste management, converting industrial solid wastes such as lithium slag, metakaolin, titanium slag, limestone powder, and steel slag into high-performance building materials can not only effectively reduce solid waste accumulation and environmental pollution but also achieve resource recycling, aligning with the concept of sustainable development.

[0004] However, existing cement-based grouting materials have many shortcomings in utilizing solid waste. First, traditional grouting materials are mostly based on ordinary Portland cement, which has insufficient early strength and is relatively expensive, making it difficult to meet the needs of efficient and economical repairs. Second, although some grouting materials have begun to incorporate solid wastes such as fly ash and slag powder, the low activity, limited production, and high transportation costs of these wastes make it difficult to increase their dosage in the grouting material, thus affecting the early strength and overall performance of the repair material. In addition, the expansion properties of existing grouting materials largely depend on external expansion agents, which not only increases costs but may also affect the quality of the grouting material due to the unstable use of the admixtures. More importantly, existing grouting materials also have significant shortcomings in terms of fluidity loss and workability. Due to their high early strength requirements and early initial setting time, and the excellent angularity of the fine aggregates used, although they have good adhesion to the grout, their fluidity is generally poor, making it difficult to meet the complex and varied construction needs in practical applications. To solve the above problems, a high-fluidity micro-expansion multi-solid waste grouting repair material and its preparation process are proposed. Summary of the Invention

[0005] (a) Technical problems to be solved

[0006] To address the problems existing in the prior art, this invention provides a high-fluidity micro-expansion multi-solid waste grouting repair material and its preparation process, in order to solve the problems mentioned in the background art, such as insufficient early strength, high cost, large loss of fluidity, and dependence on admixtures for expansion of existing grouting repair materials.

[0007] (II) Technical Solution

[0008] To achieve the above objectives, the present invention provides the following technical solution: a high-fluidity micro-expansion multi-solid waste grouting repair material, comprising a cementitious material system, composite solid waste admixture, aggregate, water, and water-reducing agent, characterized in that it is composed of the following components in parts by weight: 48-60 parts of cementitious material system, which is compounded from 42.5 ordinary Portland cement, 42.5 composite Portland cement, and 42.5R rapid-hardening sulfoaluminate cement in a ratio of (20-60)%: (20-60)%: (5-15)%;

[0009] The composite solid waste admixture consists of 12-20 parts, including lithium slag powder, metakaolin, titanium slag powder, limestone powder and steel slag powder, with a mass ratio of (20-40)%: (10-20)%: (17-25)%: (10-18)%: (10-23)%;

[0010] 18-25 parts of aggregate, including continuously graded sand (0-4.75mm) composed of spherical steel slag sand and titanium slag aggregate.

[0011] 17-23 parts water;

[0012] 0.2-0.5 parts of water-reducing agent.

[0013] The present invention is further configured such that the lithium slag powder has a specific surface area > 500 m² / kg, the metakaolin has a specific surface area > 1000 m² / kg, the titanium ore slag powder has a specific surface area of ​​400-500 m² / kg and a 28-day activity index ≥ 70%, the limestone powder has a specific surface area of ​​400-500 m² / kg and an activity index ≥ 70%, and the steel slag powder has a sieve residue of ≤ 30% on a 45 μm square hole sieve and an activity index ≥ 65%.

[0014] The present invention is further configured such that the 3-day strength of the 42.5 ordinary silicate cement is ≥25MPa, the 3-day strength of the 42.5 composite silicate cement is ≥30MPa, and the 3-day strength of the 42.5R rapid-hardening sulfoaluminate cement is ≥42.5MPa.

[0015] This invention also provides the following technical solution: a preparation process for a high-fluidity, micro-expansion, multi-solid waste grouting repair material.

[0016] S1. Mix 42.5 ordinary Portland cement, 42.5 composite Portland cement and 42.5R rapid hardening sulfoaluminate cement in a uniform dry-mixing ratio to form a cementitious material system;

[0017] S2. Mix the five solid waste admixtures, namely lithium slag powder, metakaolin, titanium slag powder, limestone powder and steel slag powder, in proportion and then add them to the cementitious material system of step S1.

[0018] S3. Dry-mix the aggregate and water-reducing agent with the spherical steel slag sand and titanium slag aggregate compound;

[0019] S4. Add water and stir until the fluidity is ≥300mm.

[0020] The present invention is further configured such that the spherical steel slag sand is prepared by centrifugally cooling molten steel in a preparation device at a speed of 10-15 m / s, and the particle size is 0-1.18 mm or 0-2.36 mm in a continuous gradation.

[0021] The present invention is further configured such that the spherical steel slag sand preparation device includes a cooling water tank, and a cross support is provided on the cooling water tank, a turntable mechanism is provided on the cross support, and an air curtain crushing mechanism is provided below the turntable mechanism, the air curtain crushing mechanism being fixedly connected to the cross support through a support rod.

[0022] The turntable mechanism includes a turntable scattering assembly rotatably mounted on the cross support, a scattering hole formed on the side wall of the turntable scattering assembly, and a drive assembly disposed on the cross support and meshing with the turntable scattering assembly.

[0023] The air curtain breaking mechanism includes an air ring fixedly connected to the support rod, and a Laval nozzle arranged in a ring array at the top of the air ring. The air ring is connected to an external inert gas tank.

[0024] The turntable mechanism is set above the center of the cooling water pool via a cross-bracing support. Molten steel is poured into the turntable mechanism, and the centrifugal force of rotation causes the molten steel to scatter. Specifically, the turntable scattering component is mounted on the cross-bracing support via bearings. The drive component rotates the turntable scattering component, causing the molten steel in the turntable scattering component to be thrown out from the scattering holes under the centrifugal force of rotation, thus forming small droplets.

[0025] The gas ring is connected to the external inert gas tank via a high-pressure gas pump. This high-pressure inert gas enters the gas ring and is then sprayed upwards through a ring-shaped array of Laval nozzles to form an annular gas curtain. The size of this annular gas curtain is larger than the outer wall size of the rotary dispersion assembly. This allows the small droplets of molten steel centrifugally dispersed by the rotary dispersion assembly to undergo secondary crushing upon impact with the gas curtain, further reducing the droplet size and resulting in particles smaller than 2.36 mm. This ensures a continuous gradation of 0-1.18 mm or 0-2.36 mm particle sizes. Furthermore, the small droplets centrifugally dispersed from the rotary dispersion assembly exhibit tailing. If directly cooled in a cooling water tank, their shape would not conform to spherical form, leading to a low yield. However, the secondary crushing by the annular gas curtain disperses the impacting droplets into multiple small spherical droplets, satisfying both the required size and ensuring a high yield of spherical droplets.

[0026] In addition, in this invention, the droplets are broken down again by the annular air curtain, which reduces the size of the droplets. This allows the scattering holes on the turntable scattering assembly to be designed to be larger than the manufacturing size to a certain extent. The enlargement of the scattering holes further improves the centrifugal efficiency of the molten steel and reduces the occurrence of clogging in the holes.

[0027] The present invention is further configured such that the turntable scattering assembly includes a turntable rotatably mounted on a cross support, and a toothed ring disposed on the outer ring of the top of the turntable;

[0028] The drive assembly includes a drive motor fixedly mounted on a cross bracket via a bracket, and a drive gear disposed on the output shaft of the drive motor.

[0029] The gear ring meshes with the drive gear.

[0030] The drive motor is supported and fixed by a U-shaped bracket, and its output shaft extends through the U-shaped bracket to its lower part. The drive gear ring is set below the U-shaped bracket and fixedly connected to the output shaft of the drive motor. The rotation of the drive motor drives the drive gear to rotate, and the drive gear meshes with the gear ring at the top of the turntable, thereby driving the turntable to rotate. Through centrifugal force, the molten steel in the turntable is scattered out through the scattering hole.

[0031] The present invention is further configured such that the diameter of the top opening of the turntable is larger than the diameter of the bottom opening, and the bottom of the inner wall of the turntable is an arched protrusion;

[0032] A retaining ring is provided at the upper end of the inner wall of the turntable, and the retaining ring is inclined downward towards the axis.

[0033] The turntable's design, wider at the top and narrower at the bottom, allows centrifugal force to propel molten steel upwards along the inner wall of the turntable as it rotates. This allows the molten steel to quickly reach the dispersion holes for centrifugal dispersion. As the molten steel rises, it impacts the retaining ring. The retaining ring, tilted downwards, prevents the molten steel from spilling outwards. Furthermore, the retaining ring's resistance increases the centrifugal pressure. The downward-tilted retaining ring also acts as a guide for the molten steel as it enters, concentrating it at the arched protrusion before dispersing it onto the inner wall for centrifugal treatment.

[0034] Without the baffle ring, molten steel is prone to spilling out of the opening. Furthermore, due to the design of the turntable being larger at the top and smaller at the bottom, the centrifugal force of the molten steel towards the periphery is relatively small, making it difficult for the molten steel to be thrown out of the spill hole. Even if it is thrown out, it is extremely easy for it to cause a trailing effect.

[0035] It should be noted that the turntable is not designed as a cylinder. In a cylinder, the molten steel accumulates at the bottom, and under the centrifugal force of rotation, it is mainly ejected from the bottom through the scattering hole, resulting in lower production efficiency.

[0036] In this invention, the bottom of the inner wall of the turntable is arched, which allows molten steel to be quickly dispersed to the inner wall after entering the cavity, and then centrifuged, thereby further improving the efficiency of centrifugal preparation.

[0037] The present invention is further configured such that the turntable scattering assembly further includes a wave-shaped spring sheet disposed on the outer circumference of the turntable;

[0038] The Laval nozzle's spray direction is parallel to the outer wall of the turntable, and the tail of the gas jet from the Laval nozzle abuts against the wave-shaped spring.

[0039] The Laval nozzle sprays in a direction parallel to the outer wall of the turntable, and the tail airflow directly impacts the wave spring, forming a high-frequency micro-vibration. The wave spring converts the airflow energy into mechanical vibration, causing periodic micro-vibrations on the outer wall of the turntable, preventing molten steel droplets from sticking together or clogging the scattering holes.

[0040] It should also be noted that the scattering holes on the turntable are tapered, with a large inner diameter and a small outer diameter, which reduces the tailing phenomenon after the molten steel is centrifugally thrown out. At the same time, the axis of the scattering holes is perpendicular to the spray direction of the Laval nozzle, so that the scattered molten steel droplets can directly impact the air curtain, thus achieving the best crushing effect.

[0041] The invention is further configured such that the cross-section of the gas ring is trapezoidal, the Laval nozzle is installed on the upper short side of the gas ring trapezoid, and the lower long side of the gas ring trapezoid is connected to an external inert gas tank.

[0042] The air ring creates an airflow compression effect through its trapezoidal cross-section design. The trapezoidal structure allows the gas to gradually accelerate from a wide inlet to a narrow outlet, avoiding turbulence and ensuring uniform and high-velocity airflow at the Laval nozzle. In addition, the compact layout of the upper short side reduces the spacing between Laval nozzles, maximizing the coverage area of ​​the annular air curtain and 100% intercepting centrifugal droplets, thus preventing leakage and breakage.

[0043] (III) Beneficial Effects

[0044] Compared with the prior art, the present invention provides a high-fluidity micro-expansion multi-solid waste grouting repair material and its preparation process, which has the following beneficial effects:

[0045] 1. This invention achieves high fluidity, micro-expansion, low cost, and excellent early strength and durability by combining the synergistic effect of three cement compounding systems and multiple solid waste admixtures with the gradation optimization of spherical steel slag sand. At the same time, it significantly improves the utilization rate of solid waste and reduces the complexity of the preparation process.

[0046] 2. This invention refines molten steel droplets into spherical particles through the combined action of centrifugal dispersion by a turntable and secondary crushing by an air curtain. This avoids the irregular shape problem caused by direct cooling and ensures that the particle size is concentrated in a continuous gradation of 0-1.18mm or 0-2.36mm, significantly improving the yield.

[0047] 3. The turntable of this invention adopts a conical structure with a larger upper part and a smaller lower part, combined with an arched protrusion on the inner wall and a retaining ring, so that the molten steel can be quickly dispersed to the scattering hole, reducing residue. The conical design of the scattering hole with a large inner diameter and a small outer diameter reduces the risk of droplet tailing. At the same time, under the action of secondary crushing by the air curtain, the hole diameter can be expanded to reduce clogging and improve centrifugal efficiency. Meanwhile, the airflow sprayed by the Laval nozzle impacts the wave spring, generating high-frequency vibration and transmitting it to the outer wall of the turntable, preventing molten steel droplets from sticking to the scattering hole or the inner wall of the turntable, ensuring continuous and stable production. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the overall structure of the spherical steel slag sand preparation device.

[0049] Figure 2 This is a schematic diagram showing the positional relationship between the drive assembly, the rotary table dispersion assembly, and the air curtain crushing mechanism of the spherical steel slag sand preparation device.

[0050] Figure 3 A partial cross-sectional schematic diagram of the rotary table mechanism of the spherical steel slag sand preparation device.

[0051] Figure 4 This is a schematic diagram showing the relationship between the orientation of the air curtain and the orientation of the molten steel dispersion.

[0052] Figure 5 This is a schematic diagram of the gas ring structure.

[0053] In the diagram: 1. Cooling water tank; 2. Cross support; 3. Turntable mechanism; 4. Air curtain breaking mechanism; 401. Air ring; 402. Laval nozzle; 5. Support rod; 6. Turntable scattering assembly; 601. Turntable; 602. Gear ring; 603. Arched protrusion; 604. Retaining ring; 605. Waveform spring; 7. Scattering hole; 8. Drive assembly; 801. Drive motor; 802. Drive gear. Detailed Implementation

[0054] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0055] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0056] In this invention, unless otherwise stated, the directional terms such as "up" and "down" generally refer to the directions shown in the accompanying drawings, or to the vertical, perpendicular, or gravitational direction; similarly, for ease of understanding and description, "left" and "right" generally refer to the left and right shown in the accompanying drawings; "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention.

[0057] Example 1: A high-fluidity, micro-expansion, multi-solid-waste grouting repair material, comprising a cementitious material system, composite solid-waste admixture, aggregate, water, and water-reducing agent, and composed of the following components in parts by weight: 48 parts of cementitious material system, which is composed of 42.5 ordinary Portland cement with a 3d strength ≥ 25 MPa, 42.5 composite Portland cement with a 3d strength ≥ 30 MPa, and 42.5R rapid-hardening sulfoaluminate cement with a 3d strength ≥ 42.5 MPa in a ratio of 47%:44%:9%;

[0058] The composite solid waste admixture consists of 12 parts, including lithium slag powder, metakaolin, titanium slag powder with a specific surface area of ​​400-500m² / kg and an activity index of ≥70% after 28 days, limestone powder with a specific surface area of ​​400-500m² / kg and an activity index of ≥70%, and steel slag powder with a sieve residue of ≤30% on a 45μm square hole sieve and an activity index of ≥65%, with a mass ratio of 38%:14%:17%:15%:16%.

[0059] To ensure strength, highly active lithium slag powder and metakaolin are used. Therefore, the specific surface area of ​​lithium slag powder needs to be greater than 500 m² / kg, the 3-day activity index needs to be above 74%, and the 28-day activity index needs to be 95%. Moreover, it is a solid waste-based material with low price. In addition, the specific surface area of ​​metakaolin needs to be greater than 1000 m² / kg. However, due to its high price and the fact that the total water absorption rate of the system is too high when the activity exceeds 20%, which can easily lead to poor flowability of the grout, its admixture should not be too high. The required metakaolin has a 3-day activity greater than 70% and a 28-day activity greater than 120%.

[0060] Furthermore, titanium slag powder and steel slag powder are solid waste-based materials with low prices. Their utilization can enrich multiple solid waste systems, mainly serving as fillers. Limestone powder is a common admixture, mainly used to fill pores and supplement strength.

[0061] Secondly, the composite solid waste admixture utilizes the inherent expansion properties of the material itself to achieve expansion, eliminating the need for an expansion agent. Through the micro-expansion properties of steel slag powder and steel slag sand, the composite solid waste admixture can ensure the micro-expansion performance of the grouting material without the use of an expansion agent.

[0062] By compounding spherical steel slag sand with a continuous gradation of particle size (0-1.18 mm or 0-2.36 mm) with naturally cooled single-size titanium slag aggregate, a high flow state is achieved through spherical shape.

[0063] 18 parts of aggregate, including continuously graded sand (0-4.75mm) composed of spherical steel slag sand and titanium slag aggregate.

[0064] 17 parts water;

[0065] 0.2 parts water-reducing agent.

[0066] Example 2: A high-fluidity micro-expansion multi-solid waste grouting repair material, comprising a cementitious material system, composite solid waste admixture, aggregate, water, and water-reducing agent, and composed of the following components in parts by weight: 60 parts of cementitious material system, which is compounded from 42.5 ordinary Portland cement with a 3d strength ≥ 25 MPa, 42.5 composite Portland cement with a 3d strength ≥ 30 MPa, and 42.5R rapid-hardening sulfoaluminate cement with a 3d strength ≥ 42.5 MPa in a ratio of 55%:30%:15%;

[0067] The composite solid waste admixture consists of 20 parts, including lithium slag powder, metakaolin, titanium slag powder with a specific surface area of ​​400-500 m² / kg and an activity index of ≥70% after 28 days, limestone powder with a specific surface area of ​​400-500 m² / kg and an activity index of ≥70%, and steel slag powder with a sieve residue of ≤30% on a 45μm square hole sieve and an activity index of ≥65%, in a mass ratio of 20%:14%:25%:18%:23%.

[0068] To ensure strength, highly active lithium slag powder and metakaolin are used. Therefore, the specific surface area of ​​lithium slag powder needs to be greater than 500 m² / kg, the 3-day activity index needs to be above 74%, and the 28-day activity index needs to be 95%. Moreover, it is a solid waste-based material with low price. In addition, the specific surface area of ​​metakaolin needs to be greater than 1000 m² / kg. However, due to its high price and the fact that the total water absorption rate of the system is too high when the activity exceeds 20%, which can easily lead to poor flowability of the grout, its admixture should not be too high. The required metakaolin has a 3-day activity greater than 70% and a 28-day activity greater than 120%.

[0069] Furthermore, titanium slag powder and steel slag powder are solid waste-based materials with low prices. Their utilization can enrich multiple solid waste systems, mainly serving as fillers. Limestone powder is a common admixture, mainly used to fill pores and supplement strength.

[0070] Secondly, the composite solid waste admixture utilizes the inherent expansion properties of the material itself to achieve expansion, eliminating the need for an expansion agent. Through the micro-expansion properties of steel slag powder and steel slag sand, the composite solid waste admixture can ensure the micro-expansion performance of the grouting material without the use of an expansion agent.

[0071] By compounding spherical steel slag sand with a continuous gradation of particle size (0-1.18 mm or 0-2.36 mm) with naturally cooled single-size titanium slag aggregate, a high flow state is achieved through spherical shape.

[0072] 25 parts of aggregate, including continuously graded sand (0-4.75mm) composed of spherical steel slag sand and titanium slag aggregate.

[0073] 23 parts water;

[0074] 0.5 parts water-reducing agent.

[0075] Increasing the amount of sulfoaluminate cement can shorten the setting time, and the initial setting time can be controlled to within 0.5 hours and the final setting time to within 1 hour. Increasing the amount of composite silicate cement is mainly to ensure early strength, while ordinary silicate cement is mainly to ensure later strength. Cement blending not only ensures early strength but also controls setting time and reduces costs.

[0076] Traditional grouting materials use a single type of cement, such as a "single-use SAC" system or a "single-use 52.5 grade silicate cement" system, or a mixture of two types of cement, but with SAC as the main component, often in a ratio of "4:1" or higher. This invention proposes a three-component cement blend, and lowers the cement grade, using 42.5 grade PO and PC as the main components. The SAC content does not exceed 15% of the total cement content. Under these conditions, the setting time is slightly longer than that of traditional grouting materials (the initial setting time of traditional grouting materials is slightly longer than 30 minutes), but the cost reduction is considerable.

[0077] Example 3, please refer to Figure 1 - Figure 5 A preparation process for a high-fluidity, micro-expansion, multi-solid waste grouting repair material.

[0078] S1. Mix 42.5 ordinary Portland cement, 42.5 composite Portland cement and 42.5R rapid hardening sulfoaluminate cement in a uniform dry-mixing ratio to form a cementitious material system;

[0079] S2. Mix the five solid waste admixtures, namely lithium slag powder, metakaolin, titanium slag powder, limestone powder and steel slag powder, in proportion and then add them to the cementitious material system of step S1.

[0080] S3. Dry-mix the aggregate and water-reducing agent with the spherical steel slag sand and titanium slag aggregate compound;

[0081] S4. Add water and stir until the fluidity is ≥300mm.

[0082] Spherical steel slag sand is produced by rapidly cooling molten steel in a preparation device at a speed of 10-15 m / s, with a continuous gradation of particle size of 0-1.18 mm or 0-2.36 mm.

[0083] The apparatus for preparing spherical steel slag sand includes a cooling water tank 1, and a cross support 2 is provided on the cooling water tank 1. A turntable mechanism 3 is provided on the cross support 2, and an air curtain crushing mechanism 4 is provided below the turntable mechanism 3. The air curtain crushing mechanism 4 is fixedly connected to the cross support 2 through a support rod 5.

[0084] The turntable mechanism 3 includes a turntable scattering assembly 6 rotatably mounted on the cross support 2, a scattering hole 7 opened on the side wall of the turntable scattering assembly 6, and a drive assembly 8 disposed on the cross support 2 and meshing with the turntable scattering assembly 6.

[0085] The air curtain breaking mechanism 4 includes an air ring 401 fixedly connected to the support rod 5, and Laval nozzles 402 arranged in a ring array at the top of the air ring 401. The air ring 401 is connected to an external inert gas tank.

[0086] The turntable mechanism 3 is set above the center of the cooling water pool 1 via the cross support 2. Molten steel is poured into the turntable mechanism 3, and the centrifugal force of rotation enables the molten steel to be scattered. Specifically, the turntable scattering component 6 is rotatably mounted on the cross support 2 via bearings. The drive component 8 rotates to drive the turntable scattering component 6 to rotate, so that the molten steel in the turntable scattering component 6 is thrown out from the scattering hole 7 under the centrifugal force of rotation, thus forming small droplets.

[0087] The connection between the gas ring 401 and the external inert gas tank is achieved through a high-pressure gas pump. This allows the inert gas to enter the gas ring 401 at high pressure and be sprayed upwards through the Laval nozzles 402 in the annular array, forming an annular gas curtain. The size of the annular gas curtain is larger than the outer wall size of the rotary dispersion assembly 6. This allows the small droplets of molten steel centrifuged from the rotary dispersion assembly 6 to undergo secondary crushing upon impact with the gas curtain, further reducing the droplet size and producing particles smaller than 2.36 mm. This ensures a continuous gradation of 0-1.18 mm or 0-2.36 mm particle size. Furthermore, the small droplets centrifuged from the rotary dispersion assembly 6 exhibit tailing. If these droplets were directly cooled and shaped in the cooling water tank 1, their shape would not conform to a spherical form, resulting in a low yield. However, after secondary crushing through the annular gas curtain, the impacting droplets disperse into multiple small spherical droplets, satisfying both the required size and ensuring a high yield of spherical droplets.

[0088] In addition, in this invention, the droplets are broken down again by the annular air curtain, which reduces the size of the droplets. This allows the scattering holes 7 on the turntable scattering component 6 to be designed to be larger than the manufacturing size to a certain extent. The enlargement of the scattering holes 7 further improves the centrifugal efficiency of the molten steel and reduces the occurrence of hole blockage.

[0089] The turntable scattering assembly 6 includes a turntable 601 rotatably mounted on a cross bracket 2, and a toothed ring 602 disposed on the outer ring of the top of the turntable 601;

[0090] The drive assembly 8 includes a drive motor 801 fixedly mounted on the cross bracket 2 via a bracket, and a drive gear 802 disposed on the output shaft of the drive motor 801;

[0091] The gear ring 602 meshes with the drive gear 802.

[0092] The drive motor 801 is supported and fixed by a U-shaped bracket, and its output shaft extends through the U-shaped bracket to its lower part. The drive gear ring 602 is set below the U-shaped bracket and is fixedly connected to the output shaft of the drive motor 801. The rotation of the drive motor 801 drives the drive gear 802 to rotate. The drive gear 802 meshes with the gear ring 602 at the top of the turntable 601, thereby driving the turntable 601 to rotate. Through centrifugal force, the molten steel in the turntable 601 is scattered out through the scattering hole 7.

[0093] The top opening diameter of turntable 601 is larger than the bottom diameter, and the bottom of the inner wall of turntable 601 is an arched protrusion 603.

[0094] A retaining ring 604 is provided on the upper end of the inner wall of the turntable 601, and the retaining ring 604 is inclined downward towards the axis.

[0095] The turntable 601, with its design that is larger at the top and smaller at the bottom, allows the centrifugal force to drive the molten steel upwards along the inner wall of the turntable 601 as it rotates. This allows the molten steel to quickly reach the scattering hole 7 for centrifugal dispersion. As the molten steel moves upwards, it will collide with the retaining ring 604. The retaining ring 604, by tilting downwards, prevents the molten steel from spilling outwards. Furthermore, the retaining force of the retaining ring 604 increases the centrifugal pressure. The downwardly tilted retaining ring 604 also serves as a guide for the molten steel as it enters, causing it to concentrate at the arched protrusion 603 and then disperse onto the inner wall for centrifugal treatment.

[0096] Without the baffle ring 604, molten steel would easily spill out of the opening, and the design of the turntable 601, which is larger at the top and smaller at the bottom, would result in less centrifugal force on the molten steel, making it difficult for the molten steel to be thrown out of the scattering hole 7. Even if it is thrown out, it is very easy for it to have a trailing effect.

[0097] It should be noted that the turntable 601 is not designed as a cylinder. The reason is that with a cylindrical design, the molten steel accumulates at the bottom, and under the centrifugal force of rotation, it is mainly ejected from the lower scattering hole 7, resulting in lower production efficiency.

[0098] In this invention, the bottom of the inner wall of the turntable 601 has an arched protrusion 603, which allows molten steel to be quickly dispersed to the inner wall after entering the cavity, and then centrifuged, thereby further improving the efficiency of centrifugal preparation.

[0099] The turntable scattering assembly 6 also includes a wave-shaped spring piece 605 disposed on the outer circumference of the turntable 601;

[0100] The spray direction of the Laval nozzle 402 is parallel to the outer wall of the turntable 601, and the tail of the gas spray from the Laval nozzle 402 abuts against the wave spring 605.

[0101] The spray direction of the Laval nozzle 402 is parallel to the outer wall of the turntable, and the tail airflow directly impacts the wave spring 605, forming a high-frequency micro-vibration. The wave spring 605 converts the airflow energy into mechanical vibration, causing the outer wall of the turntable 601 to generate periodic micro-vibrations, preventing molten steel droplets from sticking together or clogging the scattering hole 7.

[0102] It should also be noted that the scattering holes 7 on the turntable 601 are tapered, with a large inner diameter and a small outer diameter, which reduces the tailing phenomenon after the molten steel is centrifugally thrown out. At the same time, the axis of the scattering holes 7 is perpendicular to the spray direction of the Laval nozzle 402, so that the scattered molten steel droplets can directly impact the air curtain, thereby achieving the best crushing effect.

[0103] The cross-section of the gas ring 401 is trapezoidal. The Laval nozzle 402 is installed on the upper short side of the trapezoid of the gas ring 401, and the lower long side of the trapezoid of the gas ring 401 is connected to an external inert gas tank.

[0104] The air ring 401 creates an airflow compression effect through a trapezoidal cross-section design. The trapezoidal structure allows the gas to gradually accelerate from a wide inlet to a narrow outlet, avoiding turbulence and ensuring the uniformity and high velocity of the airflow in the Laval nozzle 402. In addition, the compact layout of the upper short side reduces the spacing of the Laval nozzle 402, maximizing the coverage area of ​​the annular air curtain and 100% intercepting centrifugal scattered droplets, thus avoiding leakage and breakage.

[0105] Of all the solutions mentioned above, those involving the connection between two components can be selected according to the actual situation, such as welding, bolt and nut connection, bolt or screw connection, or other known connection methods, which will not be elaborated here. For all the fixed connections mentioned above, welding is preferred. Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A preparation process for a high-fluidity, micro-expansion, multi-solid waste grouting repair material, characterized by: The high-fluidity micro-expansion multi-solid waste grouting repair material is composed of a cementitious material system, composite solid waste admixture, aggregate, water and water-reducing agent, and consists of the following components in parts by weight: 48-60 parts of cementitious material system, which is composed of 42.5 ordinary Portland cement, 42.5 composite Portland cement and 42.5R rapid hardening sulfoaluminate cement in a ratio of (45-55)%: (30-40)%: (10-15)%; The composite solid waste admixture consists of 12-20 parts, including lithium slag powder, metakaolin, titanium slag powder, limestone powder and steel slag powder, with a mass ratio of (20-40)%: (10-20)%: (17-25)%: (10-18)%: (10-23)%; 18-25 parts of aggregate, including continuously graded sand of 0-4.75mm, which is a blend of spherical steel slag sand and titanium slag aggregate; 17-23 parts water; Water-reducing agent 0.2-0.5 parts; The preparation process of the high-fluidity micro-expansion multi-solid waste grouting repair material includes the following steps: S1. Mix 42.5 ordinary Portland cement, 42.5 composite Portland cement and 42.5R rapid hardening sulfoaluminate cement in a uniform dry-mixing ratio to form a cementitious material system; S2. Mix the five solid waste admixtures, namely lithium slag powder, metakaolin, titanium slag powder, limestone powder and steel slag powder, in proportion and then add them to the cementitious material system of step S1. S3. Dry-mix the aggregate and water-reducing agent with the spherical steel slag sand and titanium slag aggregate compound; S4. Add water and stir until the fluidity is ≥300 mm; The spherical steel slag sand is produced by rapidly cooling molten steel in a preparation device by centrifugation at a speed of 10-15 m / s, with a particle size of 0-1.18 mm or 0-2.36 mm in continuous gradation. The device for preparing spherical steel slag sand includes a cooling water tank (1), and a cross support (2) is provided on the cooling water tank (1). A turntable mechanism (3) is provided on the cross support (2), and an air curtain crushing mechanism (4) is provided below the turntable mechanism (3). The air curtain crushing mechanism (4) is fixedly connected to the cross support (2) through a support rod (5). The turntable mechanism (3) includes a turntable scattering assembly (6) rotatably mounted on the cross support (2), a scattering hole (7) opened on the side wall of the turntable scattering assembly (6), and a drive assembly (8) disposed on the cross support (2) and meshing with the turntable scattering assembly (6). The air curtain breaking mechanism (4) includes an air ring (401) fixedly connected to the support rod (5), and a Laval nozzle (402) arranged in a ring array at the top of the air ring (401). The air ring (401) is connected to an external inert gas tank. The turntable scattering assembly (6) includes a turntable (601) rotatably mounted on a cross support (2), and a toothed ring (602) disposed on the outer ring of the top of the turntable (601). The drive assembly (8) includes a drive motor (801) fixedly mounted on a cross bracket (2) via a bracket, and a drive gear (802) disposed on the output shaft of the drive motor (801). The gear ring (602) and the drive gear (802) mesh; The top opening diameter of the turntable (601) is larger than the bottom diameter, and the bottom of the inner wall of the turntable (601) is an arched protrusion (603). A retaining ring (604) is provided on the upper end of the inner wall of the turntable (601), and the retaining ring (604) is inclined downward towards the axis; The turntable scattering assembly (6) also includes a wave-shaped spring sheet (605) disposed on the outer circumferential wall of the turntable (601). The Laval nozzle (402) sprays in a direction parallel to the outer wall of the turntable (601), and the tail of the gas jet from the Laval nozzle (402) abuts against the wave-shaped spring sheet (605). The cross-section of the gas ring (401) is trapezoidal, the Laval nozzle (402) is installed on the upper short side of the trapezoid of the gas ring (401), and the lower long side of the trapezoid of the gas ring (401) is connected to an external inert gas tank.

2. The preparation process of the high-fluidity micro-expansion multi-solid waste grouting repair material according to claim 1, characterized in that: The lithium slag powder has a specific surface area >500m² / kg, the metakaolin has a specific surface area >1000m² / kg, the titanium ore slag powder has a specific surface area of ​​400-500m² / kg and an activity index ≥70% after 28 days, and the steel slag powder has a sieve residue of ≤30% on a 45μm square hole sieve and an activity index ≥65%.

3. The preparation process of the high-fluidity micro-expansion multi-solid waste grouting repair material according to claim 1, characterized in that: The 42.5 ordinary silicate cement has a 3-day strength ≥25MPa, the 42.5 composite silicate cement has a 3-day strength ≥30MPa, and the 42.5R rapid-hardening sulfoaluminate cement has a 3-day strength ≥42.5MPa.

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