Gangue slurry stirrer for separation grouting

Abstract

The utility model discloses a gangue slurry stirrer for separation layer grouting in the technical field of coal mine separation layer filling, which comprises a tank body with a cover body at the top, the cover body at the top of the tank body is fixedly connected with a speed reducing motor through a rack, and the output end of the speed reducing motor is coaxially connected with a rotating impeller through a coupler. The tank body comprises a straight barrel section and a conical barrel section, a feeding pipe and an overflow pipe are arranged on the upper portion of the straight barrel section, a plurality of spoilers are arranged on the inner wall of the straight barrel section in a surrounding mode, a discharging pipe is arranged on the lower portion of the conical barrel section, the rotating impeller comprises a stirring shaft, a tangential blade set and an anchor type blade set, and the tangential blade set and the anchor type blade set are arranged on a shaft body from top to bottom. And the tangential blade group and the anchor-type blade group form included angles with the stirring shaft, and the directions of the included angles are opposite. By adopting the multi-stage layered stirring structure and the design of the spoilers, the problems of coarse grain deposition and non-uniform dispersion of fine silt of gangue slurry for separation grouting caused by circulating dead angles of the conventional stirring device are solved.

Description

Technical Field

[0001] This utility model relates to a gangue slurry mixer for delamination grouting, belonging to the field of coal mine delamination filling technology. Background Technology

[0002] In coal mine overburden separation grouting technology, the slurry formed by mixing crushed coal gangue with mine water needs to be transported to the separation space in the goaf through grouting pipelines to support the critical layer and control surface subsidence. However, the heterogeneous mixed system (coarse particles and fine mud) formed after the gangue particles are crushed and dissociated exhibits significant sedimentation differences: coarse particles, due to their high density and large particle size, settle rapidly in the buffer pool; while fine mud, due to its high viscosity and small particle size, remains suspended in the slurry for a long time. This difference in sedimentation rate causes the slurry to segregate and stratify during transportation, forming a heterogeneous fluid structure, which seriously restricts the stability and filling effect of the grouting process.

[0003] In existing technologies, conventional vertical or horizontal mixers achieve slurry mixing by driving blades to rotate through a single mixing shaft. However, their mixing flow field has dead zones, making it difficult to overcome the density gradient difference between coarse particles and fine mud. Specifically, coarse particles continue to deposit in the mixing blind zone, while fine mud cannot fully contact the coarse particles due to viscosity, resulting in uneven slurry concentration distribution. Therefore, there is an urgent need to develop a new type of mixer to ensure the continuity of the grouting process and the stability of the mechanical properties of the filling body. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a gangue slurry mixer for delamination grouting. By adopting a multi-stage layered mixing structure and a baffle plate design, it solves the problem of coarse particle deposition and uneven dispersion of fine mud in gangue slurry during delamination grouting caused by the dead zone of circulation in existing mixing devices, thus ensuring the continuity of the grouting process and the stability of the mechanical properties of the filling body.

[0005] To achieve the above objectives, this utility model employs the following technical solution:

[0006] This utility model provides a gangue slurry mixer for delamination grouting, including a tank with a top cover. The top cover of the tank is fixedly connected to a geared motor via a frame, and the output end of the geared motor is coaxially connected to a rotating impeller via a coupling. The tank includes a straight barrel section and a conical barrel section. The upper part of the straight barrel section is provided with an inlet pipe and an overflow pipe, and the inner wall of the straight barrel section is surrounded by multiple baffles. The lower part of the conical barrel section is provided with an outlet pipe. The rotating impeller includes a stirring shaft and tangential blade groups and anchor blade groups arranged from top to bottom on the shaft. The tangential blade groups and anchor blade groups form an angle with the stirring shaft, and the directions of the angles are opposite. The bottom end of the stirring shaft is inserted into a support at the bottom of the tank.

[0007] Furthermore, the tangential blade assembly includes multiple tangential blades distributed circumferentially along the stirring shaft, and the angle between each tangential blade and the centerline of the stirring shaft is 5° to 85°.

[0008] Furthermore, the anchor blade assembly includes multiple anchor blades distributed circumferentially along the stirring shaft, and the angle between each anchor blade and the centerline of the stirring shaft is 5° to 85°.

[0009] Furthermore, the anchor-shaped blade comprises a horizontal steel plate, a vertical steel plate, and an inclined steel plate connected in sequence.

[0010] Furthermore, the spoiler includes a vertically fixed back plate and a vertical plate. The vertical plate has multiple horizontally arranged trapezoidal plates along its longitudinal direction, and the bottom edge of each trapezoidal plate is connected to the back plate.

[0011] Furthermore, both the discharge pipe and the inlet pipe are equipped with flanges.

[0012] Compared with the prior art, the beneficial effects achieved by this utility model are as follows:

[0013] This invention solves the problems of coarse particle deposition and uneven dispersion of fine mud in gangue slurry caused by dead zones in existing mixing devices by employing a multi-stage layered stirring structure and baffle plate design. Tangential blades are installed at the center of the upper region of the tank to drive the suspended fine mud flow from top to bottom, while anchor-shaped blades are installed in the lower region to drive the settling coarse particle flow from bottom to top. The collision of these two flows creates a large circulating vortex within the tank, achieving uniform mixing of the gangue slurry. Furthermore, multiple baffle plates are evenly arranged on the tank wall, which not only prevent the slurry from rotating and segregating within the tank but also increase turbulence intensity when the gangue slurry impacts the baffle plates, further promoting the homogeneity of the gangue slurry. Attached Figure Description

[0014] The accompanying drawings, which form part of this specification, are used to provide a further understanding of this utility model. The illustrative embodiments and descriptions of this utility model are used to explain this utility model and do not constitute an undue limitation thereof. In the drawings:

[0015] Figure 1 A schematic diagram of the overall structure of a gangue slurry mixer for delamination grouting provided for an embodiment of this utility model;

[0016] Figure 2 A schematic diagram of the tank structure of a gangue slurry mixer for delamination grouting provided for an embodiment of this utility model;

[0017] Figure 3A front view schematic diagram of the rotating impeller of a gangue slurry mixer for delamination grouting provided for an embodiment of this utility model;

[0018] Figure 4 A left-side structural schematic diagram of the rotating impeller of a gangue slurry mixer for delamination grouting provided in an embodiment of this utility model;

[0019] Figure 5 A schematic diagram of the anchor-type blade structure of a gangue slurry mixer for delamination grouting provided for an embodiment of this utility model;

[0020] Figure 6 A schematic front view of the baffle plate of a gangue slurry mixer for delamination grouting provided in an embodiment of this utility model;

[0021] Figure 7 A top view of the baffle plate of a gangue slurry mixer for delamination grouting provided in an embodiment of this utility model;

[0022] In the diagram: 1. Gear motor; 2. Coupling; 3. Frame; 4. Baffle; 401. Back plate; 402. Vertical plate; 403. Trapezoidal plate; 5. Rotating impeller; 501. Agitator shaft; 502. Tangential blades; 503. Anchor blades; 5031. Horizontal steel plate; 5032. Vertical steel plate; 5033. Inclined steel plate; 6. Support; 7. Tank; 701. Straight barrel section; 702. Conical barrel section; 703. Discharge pipe; 704. Inlet pipe; 705. Overflow pipe. Detailed Implementation

[0023] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0024] The following detailed description is exemplary and intended to provide further detailed explanation of the present invention. Unless otherwise specified, all technical terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this invention.

[0025] Example:

[0026] Please see Figure 1This embodiment provides a gangue slurry mixer for delamination grouting. Structurally, it includes a tank 7. A geared motor 1 is fixedly connected to the top of the tank 7 via a frame 3. The output end of the geared motor 1 is coaxially connected to a rotating impeller 5 via a coupling 2. The bottom end of the shaft of the rotating impeller 5 is inserted into a support 6, and the bottom of the support 6 is connected to the bottom of the tank 7. In this embodiment, the geared motor 1 is a hardened gear reducer with an SAE flange interface at the output shaft end. The power is adapted to 18.5~45kW, and the output speed is 50~150rpm, matching the viscosity requirements of the gangue slurry (5000~15000cP). The coupling 2 is a drum-shaped gear coupling made of 45# steel forgings, with a meshing clearance of ≤0.1mm between the inner gear sleeve and the outer gear ring, a rated torque of 2000~5000N·m, and a radial runout angle tolerance of ±1.5.

[0027] Please refer to the following: Figure 2 The tank 7 comprises a straight cylindrical section 701 and a conical cylindrical section 702. The upper part of the straight cylindrical section 701 is equipped with an inlet pipe 704 and an overflow pipe 705, while the lower part of the conical cylindrical section 702 is equipped with an outlet pipe 703. Both the outlet pipe 703 and the inlet pipe 704 are fitted with flanges. The vertical cylindrical wall design of the straight cylindrical section 701 provides a stable axial flow space for slurry mixing, preventing premature dissipation of turbulent energy. The tapered structure of the conical cylindrical section 702 creates a dynamic pressure gradient through changes in the fluid cross-sectional area, forcing coarse particles to aggregate towards the vortex center under the balance of centrifugal force and gravity, effectively suppressing bottom deposition. The symmetrical layout of the overflow pipe 705 and the inlet pipe 704 enables slurry circulation self-balancing, preventing local overload. The outlet pipe 703 and the inlet pipe 704 employ a flange sealing design, ensuring zero leakage under high-pressure grouting conditions through high-precision end-face fitting. Simultaneously, the standardized design of the flange interface supports quick disassembly and maintenance, adapting to different grouting pipeline configuration requirements. The straight barrel section 701 and the conical barrel section 702 are welded from Q345B low-alloy steel plates with a thickness of 8-12mm. The internal surface is overlaid with a 1.5-3mm thick ceramic wear-resistant layer (such as an Al2O3-TiO2 composite coating) to balance structural strength and resistance to scouring by gangue slurry. The flanges (outlet pipe 703, inlet pipe 704) are forged from 304 stainless steel, with a sealing surface finish of Ra≤3.2μm. The flange standard conforms to HG / T20592 PN16 to ensure reliable sealing under high-pressure grouting conditions.

[0028] Please refer to the following: Figure 3 , Figure 4 and Figure 5The rotating impeller 5 includes a stirring shaft 501, and the stirring shaft 501 is provided with several tangential blades 502 and several anchor-shaped blades 503 from top to bottom. The tangential blades 502 are cuboids, and the angle α between the tangential blades 502 and the center line of the stirring shaft 501 is 5° to 85°. The anchor-shaped blades 503 include a horizontal steel plate 5031, a vertical steel plate 5032, and an inclined steel plate 5033. The angle β between the anchor-shaped blades 503 and the center line of the stirring shaft 501 is 5° to 85°, and the directions of the angles α and β are opposite. The tangential blade 502 adopts a cuboid structure, and its inclined angle α with the stirring shaft 501 forms a spiral guide surface, generating directional shear force on the suspended fine mud and driving the slurry to move axially downward. The anchor blade 503, through a composite structure of horizontal steel plate 5031, vertical steel plate 5032, and inclined steel plate 5033, combined with a reverse angle β, applies a reverse lift force to the settling coarse particles, forming forced convection from bottom to top. The reverse inclination angle design of the two blade groups enables the slurry to generate bidirectional vortex collision, significantly improving the interfacial penetration efficiency of coarse and fine particles. The rigid support structure of the support 6 inserted at the end of the stirring shaft 501 suppresses radial runout under high-speed rotation through a dynamic lubrication film in the shaft-support gap, reducing vibration noise and extending the service life of the transmission system. The geared motor 1 is rigidly connected to the stirring shaft 501 through the coupling 2. Its torque output characteristics are adapted to changes in slurry viscosity, ensuring that the impeller still has high torque output capability at low speeds and avoiding sudden load changes caused by coarse particle blockage.

[0029] In this embodiment, the stirring shaft 501 is made of 40Cr alloy steel with quenching and tempering treatment, with a surface hardness of HRC45-50. The shaft diameter is 80-120mm, and the length is adapted to the height of the tank (1.5-3m). The shaft end and the section mating with the support 6 are machined with a J-type labyrinth seal groove to prevent slurry from seeping into the bearing. The tangential blade 502 is a rectangular block rolled from 65Mn spring steel. The dimensions of a single blade (length × width × thickness) are 0-400mm × 60-100mm × 10-15mm. The angle α between the blade and the centerline of the stirring shaft is preferably 30°-60°. The surface is nitrided (layer depth 0.2-0.4mm) to improve its resistance to abrasive wear. The anchor-type blade 503 is welded from Q235B steel plates. The thickness of the horizontal steel plate 5031 is 12-18mm, and the thickness of the vertical steel plate 5032 and the inclined steel plate 5033 is 8-12mm. The angle β between the blade and the center line of the stirring shaft is 40°-70°, and the direction is opposite to α. The blade tip is rounded with R5-R10 to avoid dead zones in the slurry flow. The support 6 is integrally formed from ZG270-500 cast steel, with a copper-based graphite self-lubricating sleeve embedded in the inner hole. The sleeve is clearance-fitted with the stirring shaft 501 (H8 / f7). A triangular reinforcing rib is added at the bottom where it is welded to the tank body 7, and the rib thickness is 12-18mm.

[0030] It should be noted that the horizontal steel plate 5031, serving as the horizontal base plate of the anchor blade 503, is directly welded to the surface of the stirring shaft 501. It bears the main mechanical load of the blade assembly, efficiently transmitting the rotational torque of the stirring shaft to the blade tip, thus preventing stress concentration and blade root fracture. Its thickness (12-18 mm) and width (matching the height of the vertical steel plate) are designed to ensure structural rigidity under the impact of coarse-grained slurry, preventing blade deformation. The horizontal extension surface of the horizontal steel plate 5031 forms a bucket-like structure during rotation, creating a "scooping" effect on coarse particles deposited at the bottom of the tank (conical section 702 area), forcibly lifting them into the slurry circulation vortex and breaking up the static deposition layer. The vertical steel plate 5032 is arranged perpendicular to the axis of the stirring shaft 501, generating vertical shear force during rotation to physically break up agglomerated coarse particles in the slurry, reducing particle size distribution dispersion. The spaced distribution of the plates forms a flow channel partition, dividing the slurry into multiple sub-flows, increasing the contact area between coarse and fine particles, and improving mixing efficiency. The vertical plate surface of the vertical section 5032 forms a 90° angle with the mainstream direction of the slurry, generating local resistance, weakening the intensity of the single-direction vortex in the tank, and preventing excessive stratification of the slurry due to centrifugal force. The inclined section 5033 forms an angle β (5°~85°) with the axis of the stirring shaft 501. Its inclined surface generates oblique hydrodynamic force when rotating, lifting coarse particles along the inclined direction, which counteracts the downward fine mud flow driven by the tangential blades 502, enhancing the probability of coarse-fine particle collision. The trapezoidal cross-section of the inclined section 5033 (the lower bottom is connected to the back plate) forms a gradually narrowing flow channel, causing the slurry velocity to change gradient as it flows through the inclined plate, inducing local turbulence. This, combined with the vertical shearing effect of the vertical section 5032, achieves three-dimensional mixing of the slurry in the axial, radial, and tangential directions. The horizontal steel plate 5031 "scoops up" the coarse particles at the bottom, the vertical steel plate 5032 crushes and diverts them, and the inclined steel plate 5033 provides lifting power. These three components work together to achieve continuous suspension and circulation of coarse particles, completely eliminating the mixing blind spots caused by coarse particle deposition in traditional mixers. The horizontal steel plate bears the main load, while the vertical and inclined steel plates share the fluid resistance. Through mechanical distribution, the stress on individual blades is reduced, thus reducing the torque requirement of the anchor-type blade assembly for the same mixing efficiency. The thick horizontal steel plate resists wear, the spaced vertical steel plate reduces the impact area, and the trapezoidal cross-section of the inclined steel plate avoids stress concentration. The combined material (Q235B) and surface treatment (rounded corners) of these three components extend the blade assembly's lifespan compared to traditional anchor-type mixers. The above solution addresses the mixing efficiency bottleneck caused by the single function of traditional blades through an asymmetrical combination structure of horizontal, vertical, and oblique blades. The synergistic design of the three-blade mechanical division of labor and flow field control overcomes the technical bias that "increasing the number of blades can improve mixing." Structural parameters (such as thickness and inclination angle) can be adapted to different slurry densities (1.2–1.8 g / cm³). 3 The range of particle sizes (0.1-5mm) meets the diverse needs of mine delamination grouting.

[0031] Please refer to the following: Figure 6 and Figure 7 The inner wall of the straight section 701 is equipped with several baffles 4, each including a back plate 401, several vertical plates 402, and several trapezoidal plates 403. The back plate 401 and vertical plates 402 are rectangular, while the trapezoidal plates 403 are trapezoidal. The lower edge of each trapezoidal plate 403 is connected to the back plate 401, and the trapezoidal plates 403 are connected to each other via the vertical plates 402. The back plate 401 and vertical plates 402 serve as fixed bases, and the stepped distribution of the trapezoidal plates 403 creates multi-directional reflective surfaces in the slurry flow field. The inclined design of the trapezoidal plates 403 decomposes the mainstream eddy current into local micro-turbulence, while the vertical plates 402 generate secondary vortices through vertical obstruction, disrupting the slurry stratification trend. This composite structure can cover the entire height range of the straight section 701, achieving homogenization of the flow field across the entire domain. In this embodiment, the back plate 401 is made of Q235B steel plate with a thickness of 10-15mm, the vertical plate 402 has a height of 80-120mm and is evenly distributed at intervals of 200-300mm; the trapezoidal plate 403 is made of wear-resistant NM400 steel plate laser-cut, with a bottom width of 100-150mm, an inclination angle of 45°-60°, and a plate thickness of 8-12mm. It is fixed to the back plate 401 by intermittent fillet welds, with the weld length accounting for ≥60%.

[0032] The specific working process is as follows: The geared motor 1 sequentially drives the coupling 2 and the impeller 5 to rotate. The gangue slurry enters the tank 7 through the feed pipe 704. The rotation of the tangential blade 502 causes the suspended fine mud to flow from top to bottom, while the rotation of the anchor blade 503 causes the settled coarse particles to flow from bottom to top. The collision of these two streams creates a large circulating vortex within the tank. This vortex collides with the baffle plate 4 to prevent the slurry from rotating, segregating, and stratifying within the tank, further mixing the coarse and fine mud particles in the gangue slurry, thus achieving uniform mixing. In summary, this solution achieves full-scale mixing of the gangue slurry through the synergistic effect of the straight-cone dual-stage tank, the bidirectional impeller assembly, and the multi-stage baffle plate, overcoming the segregation and stratification problem caused by particle density differences in traditional mixers. The modular flange interface and rigid support structure design significantly improve the equipment's adaptability to complex working conditions and ease of maintenance. The flow field control mechanism without dead angles can be adapted to gangue slurry with different particle size ratios, meeting the stringent requirements of slurry uniformity in the delamination grouting process.

[0033] As is known from common technical knowledge, this utility model can be implemented through other embodiments that do not depart from its spirit or essential characteristics. Therefore, the disclosed embodiments described above are merely illustrative in all respects and are not the only ones. All modifications within the scope of this utility model or its equivalents are included in this utility model.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although the utility model has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of this utility model. Any modifications or equivalent substitutions that do not depart from the spirit and scope of this utility model should be covered within the protection scope of the claims of this utility model.

Claims

1. A gangue slurry mixer for delamination grouting, characterized in that, The system includes a trough (7) with a top cover. The top cover of the trough (7) is fixedly connected to a geared motor (1) via a frame (3). The output end of the geared motor (1) is coaxially connected to a rotating impeller (5) via a coupling (2). The trough (7) includes a straight barrel section (701) and a conical barrel section (702). The upper part of the straight barrel section (701) is provided with an inlet pipe (704) and an overflow pipe (705). The inner part of the straight barrel section (701) is... The wall is surrounded by multiple baffles (4), and the lower part of the cone section (702) is provided with a discharge pipe (703). The rotating impeller (5) includes a stirring shaft (501) and tangential blade groups and anchor blade groups arranged from top to bottom on the shaft. The tangential blade groups and anchor blade groups form an angle with the stirring shaft (501) and the angle directions are opposite. The bottom end of the stirring shaft (501) is inserted into the support (6) at the bottom of the tank (7).

2. The gangue slurry mixer for delamination grouting according to claim 1, characterized in that, The tangential blade group includes multiple tangential blades (502) distributed circumferentially along the stirring shaft (501), and the angle between each tangential blade (502) and the center line of the stirring shaft (501) is 5° to 85°.

3. The gangue slurry mixer for delamination grouting according to claim 1, characterized in that, The anchor blade group includes multiple anchor blades (503) distributed circumferentially along the stirring shaft (501), and the angle between each anchor blade (503) and the center line of the stirring shaft (501) is 5° to 85°.

4. The gangue slurry mixer for delamination grouting according to claim 3, characterized in that, The anchor-shaped blade (503) includes a horizontal steel plate (5031), a vertical steel plate (5032), and an inclined steel plate (5033) connected in sequence.

5. The gangue slurry mixer for delamination grouting according to claim 1, characterized in that, The spoiler (4) includes a vertically fixed back plate (401) and a vertical plate (402). The vertical plate (402) has multiple horizontally arranged trapezoidal plates (403) along its longitudinal direction, and the bottom edge of each trapezoidal plate (403) is connected to the back plate (401).

6. The gangue slurry mixer for delamination grouting according to claim 1, characterized in that, Both the discharge pipe (703) and the inlet pipe (704) are equipped with flanges.

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