A material zone activation device for a ball mill

Abstract

The application discloses a material area activation device of a ball mill, which comprises at least one activation module arranged on the inner wall of a mill barrel; the activation module rotates synchronously with the mill barrel, and the activation module has at least one activation piece extending into a dead material area in the mill; the activation piece is used for forcibly stirring the material in the dead material area, and a radial activation speed difference is formed to realize radial activation of the material in the dead material area; wherein the dead material area refers to a low-speed material area with the minimum "material-ball" speed difference below the material surface in the mill barrel; the activation piece is arranged in the circumferential direction of the mill and is inclined in the reverse direction of the material flow, and is used for generating a reverse thrust in the reverse direction of the material flow when rotating, thereby prolonging the residence time of the material in the mill. The application has the characteristics of reasonable structure design, good activation effect and controllable residence time, can effectively break the "dead material area" in the mill, control the material flow speed in the mill, improve the grinding efficiency of the mill, reduce the power consumption of the grinding, and improve the controllability of the finished product quality.

Description

Technical Field

[0001] This invention belongs to the field of powder processing technology, and particularly relates to a material zone activation device for a ball mill. Background Technology

[0002] Ball mills, as traditional grinding equipment, have been widely used in industries such as cement and mining due to their stable performance, simple operation, and excellent product quality. According to incomplete statistics, there are approximately 44,000 ball mills in operation in the global cement industry, of which 24,000 are operating in China. Therefore, the market potential for high-efficiency ball mill technology is enormous.

[0003] The working principle of a ball mill is to use a rotating cylinder to lift the grinding media (such as steel balls, steel segments, ceramic balls, etc.) and materials inside the mill to a certain height, and then throw them down under the action of gravity. During the lifting and falling process, the materials mixed between adjacent grinding media are crushed or sheared into smaller particles by the impact of the grinding media, thereby achieving grinding.

[0004] Based on the working principle of ball mills, improving the grinding efficiency requires enhancing both the "impact" and "shear" effects. "Impact" primarily relies on velocity; the higher the grinding media are carried within the mill, the greater their kinetic energy when they fall back to the lower material surface, resulting in a better "impact" effect. "Shear" is essentially "rubbing"; to improve the "shear" effect, the relative velocity between adjacent grinding media needs to be increased. The greater the relative velocity, the stronger the "shear" grinding effect.

[0005] To improve grinding efficiency, some existing technologies have proposed improvement solutions. For example, Chinese Patent Publication No. CN208928294U discloses an activation device for adjusting the material throughput of a ball mill, which controls the material flow rate and residence time by dynamically adjusting the opening area, improving the ball-to-material ratio in the cylinder, and increasing grinding efficiency; Chinese Patent Publication No. CN208990922U discloses an activation device for ceramic grinding media in a ball mill, which optimizes the movement state of the ceramic grinding media through inclined openings and concave-convex structures, enhances lifting capacity, reduces the central ineffective area, reduces material flow rate, and achieves energy saving and consumption reduction; Chinese Patent Publication No. C N108160232A discloses a cement mill activation device, which guides the grinding media and materials to move in layers according to particle size by setting an activation cone with an angle and a staggered arrangement structure, avoiding the mixing of coarse and fine particles and enhancing the grinding capacity of the fine grinding chamber. Chinese Patent Publication No. CN108465519A discloses a cement ball mill activation device, which uses magnets to disperse charges and lifting rods to control the movement trajectory of the grinding media, thereby extending the residence time of large particles, reducing the flow rate, eliminating grinding dead zones, and improving grinding efficiency and hourly output. It is especially suitable for the needs of enhanced grinding in the fine grinding chamber.

[0006] However, existing ball mills suffer from a common, long-standing problem in actual operation. For example... Figure 1 As shown in the figure, discrete element simulation calculations of traditional ball mills reveal two regions within the mill's axial cross-section: a high-speed region A with speeds ranging from 1.0 to 2.7 m / s and a low-speed region B with speeds <1 m / s or even close to 0 m / s. Region B accounts for approximately 50% of the material surface area. Region A is formed by the grinding media and material near the wall (i.e., close to the inner wall of the mill cylinder) being effectively carried to a certain height by the mill and then thrown down; this high-speed region is called the throwing zone. Region B, on the other hand, does not create a high-speed "impact" grinding effect similar to region A because the grinding media and material cannot be effectively carried to a certain height by the mill. Furthermore, since the speeds of the grinding media and material are essentially the same, the relative speed difference between the grinding media and material is small or zero, resulting in a weak "shearing" grinding effect between the grinding media and material; this low-speed region is called the "dead material zone." While existing improvement technologies have enhanced the activation effect of the mill to some extent, their activation effect on the "dead material zone" is limited, and it can even be said that they have failed to activate the "dead material zone" and have failed to fundamentally solve the problem of low material grinding efficiency in the low-speed zone.

[0007] The material and grinding media in the "dead zone" of a ball mill not only fail to generate sufficient shearing and impact crushing effects, but also rotate with the mill cylinder, consuming a large amount of the mill's power. This is the main reason why the energy utilization rate of ball mills is less than 3%. In addition, traditional ball mills have few means to adjust the residence time of materials inside the mill, further limiting the mill's fine grinding capacity and grinding efficiency.

[0008] Therefore, how to effectively overcome the "dead material zone" inside the mill, while simultaneously achieving flexible control over the material flow rate inside the mill, thereby improving the grinding efficiency of the ball mill, reducing grinding power consumption, and enhancing the controllability of finished product quality, is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0009] To address the common problems existing in the prior art, this invention provides a material zone activation device for a ball mill, which features a reasonable structural design, good activation effect, and controllable residence time. It can effectively break the "dead material zone" in the mill and control the material flow rate in the mill, thereby improving the grinding efficiency of the mill, reducing grinding power consumption, and improving the controllability of finished product quality.

[0010] This invention is implemented as follows: an activation device for the feed zone of a ball mill, comprising: At least one activation module is disposed on the inner wall of the mill cylinder; The activation module rotates synchronously with the mill cylinder, and the activation module has at least one activation element that extends into the dead material zone inside the mill. The activation element is used to forcibly agitate the material in the dead material zone inside the mill, construct a radial activation speed difference, and realize the radial activation of the material in the dead material zone. The dead material zone refers to the low-speed material zone located below the material surface inside the mill cylinder where the "material-ball" speed difference is the smallest. The activator is inclined in the circumferential direction of the mill against the material flow direction, and is used to generate a reverse thrust against the material flow direction when rotating, thereby prolonging the residence time of the material in the mill.

[0011] In the above technical solution, preferably, the activating element is a gradient activation blade, which is fixed on the first support ring plate and arranged between two first support ring plates. The first support ring plate is fixed on the support assembly, and the support assembly is fixed on the mill cylinder. The ratio of the length of a single gradient activation blade in the coarse grinding chamber to the effective length of the coarse grinding chamber is 0.11~0.41, and the ratio of the length of a single gradient activation blade in the fine grinding chamber to the effective length of the fine grinding chamber is 0.05~0.16. The angle between the gradient activation blades and the mill radial direction The angle between the gradient activation blades and the mill axis is 25°~35°. The range is 20° to 40°.

[0012] In the above technical solution, it is further preferred that the ratio of the inner diameter of the first support ring plate to the effective inner diameter of the mill cylinder is 0.65~0.85, and the ratio of the outer diameter of the first support ring plate to the effective inner diameter of the mill cylinder is 0.7~0.9.

[0013] In the above technical solution, it is further preferred that the gradient activation blade is a straight plate or a spiral curved plate; when it is a spiral curved plate, the end face profile of any point on the curved plate has an angle with the radial direction of the mill. The angle between the contour normal of any point on the curved panel and the mill axis is 25°~35°. The range is 20° to 40°.

[0014] In the above technical solution, a further preferred embodiment is that both the coarse grinding chamber and the fine grinding chamber of the mill are equipped with gradient activation modules, and the number of gradient activation modules in the coarse grinding chamber is [not specified]. The number of gradient activation modules in the fine grinding chamber satisfy:

[0015]

[0016] In the formula, The effective length of the coarse grinding chamber. The effective length of the fine grinding chamber. =250~500mm, =150~250mm, =150~250mm, =150~250mm, =400~800mm, =400~800mm.

[0017] In the above technical solution, preferably, the activating element is a high-efficiency activating blade, which is installed on the second support ring plate and arranged between the two second support ring plates. The second support ring plate is fixed on the support assembly, and the support assembly is fixed on the mill cylinder. The ratio of the length of a single high-efficiency activating blade in the coarse grinding chamber to the effective length of the coarse grinding chamber is 0.22~0.85, and the ratio of the length of a single high-efficiency activating blade in the fine grinding chamber to the effective length of the fine grinding chamber is 0.1~0.42. The angle between the highly activated blades and the radial direction of the mill. The angle between the blades and the mill axis is 25°~35°. The range is 20° to 40°.

[0018] In the above technical solution, more preferably, the ratio of the inner diameter of the second support ring plate to the effective inner diameter of the mill cylinder is 0.65~0.85, and the ratio of the outer diameter of the second support ring plate to the effective inner diameter of the mill cylinder is 0.7~0.9. In the above technical solution, more preferably, the high-efficiency activation blade is a straight plate or a spiral curved plate; when it is a spiral curved plate, the angle between the end face profile of any point on the curved plate and the radial direction of the mill is... The angle between the contour normal of any point on the curved panel and the mill axis is 25°~35°. The range is 20° to 40°.

[0019] In the above technical solution, a further preferred embodiment is that both the coarse grinding chamber and the fine grinding chamber of the mill are equipped with high-efficiency activation modules, and the number of high-efficiency activation modules in the coarse grinding chamber is [not specified]. The number of high-efficiency activation modules in the fine grinding chamber satisfy:

[0020]

[0021] In the formula, The effective length of the coarse grinding chamber. The effective length of the fine grinding chamber. =250~500mm, =150~250mm, =150~250mm, =150~250mm, =250~500mm, =1500±500mm, =1500±500mm.

[0022] In the above technical solution, it is further preferred that the two ends of the highly effective activating blade are fixedly installed on the second support ring plate.

[0023] In the above technical solution, a further preferred embodiment is that one end of the high-efficiency activation blade is rotatably mounted on the second support ring plate, and the other end is fixedly mounted on the second support ring plate, and the angle of this end on the second support ring plate along the circumference of the mill can be adjusted.

[0024] In the above technical solution, a more preferred embodiment is that the end of the high-efficiency activation blade fixedly installed on the second support ring plate is adjusted by 0~15° along the circumference of the mill on the second support ring plate.

[0025] In the above technical solution, a more preferred embodiment is that one end of the high-efficiency activation blade is rotatably connected to the bearing seat via a blade support ball bearing, and the bearing seat is fastened to the second support ring plate. The other end of the high-efficiency activation blade is fastened to the second support ring plate via a blade positioning seat. The high-efficiency activation blade has at least one U-shaped groove for adjusting the position of the high-efficiency activation blade at the connection with the blade positioning seat, and the second support ring plate has multiple adjustment holes for adjusting the installation position of the blade positioning seat at the connection with the blade positioning seat.

[0026] In the above technical solution, a further preferred embodiment is that the support assembly includes a support liner, which is fixed to the mill cylinder, and a corresponding support ring plate is fixed to the support liner.

[0027] In the above technical solution, a more preferred embodiment is that the support liner is divided into an inlay section and a support section. The inlay section is inlaid and fixed on the mill cylinder and is flush with the mill liner in the corresponding mill chamber, while the support section extends toward the center of the mill.

[0028] In the above technical solution, a more preferred embodiment is that the corresponding bracket ring plate is fixed on the support section.

[0029] In the above technical solution, a further preferred embodiment is that the support liner is cast from wear-resistant cast steel.

[0030] In the above technical solution, preferably, the activating element includes an activation ring, flow-controlling activation blades, and a flow-through perforated plate. The flow-through perforated plate has a porous structure for allowing some material to pass through. The flow-through perforated plate is disposed within the activation ring, and its porosity is 15-35%. The flow-controlling activation blades are disposed on the activation ring, and the angle between the flow-controlling activation blades and the activation ring is... The angle is 15° to 45°; the activation ring is fixed on the support assembly, and the support assembly is fixed on the mill cylinder.

[0031] In the above technical solution, preferably, the mill includes a mill cylinder and a mill inlet and a mill outlet located at both ends of the mill cylinder. Along the direction from the mill inlet to the mill outlet, the mill cylinder is divided into a coarse grinding chamber and a fine grinding chamber. A partition plate is provided between the coarse grinding chamber and the fine grinding chamber. Grinding chamber liners are provided on the inner walls of the coarse grinding chamber and the fine grinding chamber, respectively. A mill feed chute is provided at the mill inlet. A grinding grate is provided at the end of the mill cylinder near the mill outlet.

[0032] The present invention has the following advantages and beneficial effects: 1. The activating element of this invention extends into the dead material zone, forcibly agitating the material and grinding media, creating a radial velocity difference, so that the material in the originally relatively static dead material zone re-participates in the grinding process, breaking the dead material zone, significantly improving the "shearing" grinding effect and the "impact" crushing effect, improving grinding efficiency, and effectively reducing the power consumption of the mill; moreover, the activating element is inclined against the material flow direction, generating a counter-thrust force on the material, and the residence time of the material in the mill can be flexibly extended by adjusting the tilt angle, number and arrangement of the blades according to the material characteristics and finished product requirements, solving the problem of limited means of adjusting the material residence time in the prior art.

[0033] 2. The material zone activation device of this invention fundamentally solves the common problems of "dead material zone" inside the mill and limited means of adjusting material residence time in the mill in ball mills. It reduces the power consumption of the mill and extends the residence time of material inside the mill. Verified by EDEM discrete element simulation and semi-industrial test, under the same conditions, compared with traditional ball mills, the main power consumption of the finished product is reduced by 36%~44.1%, the residence time of material inside the mill is increased by 20%~37%, and the fine grinding capacity and grinding efficiency of the ball mill are significantly improved. The fineness of the output mill is reduced by 10.2~12.1 percentage points, the specific surface area is increased by 9.4%~22.8%, the sphericity of particles is increased by 0.122~0.162, the 3-day strength is increased by 2.4~4.3 MPa (increase of 9.3%~16.6%), and the 28-day strength is increased by 2.8~3.4 MPa (increase of 5.9%~7.1%), and the quality of the finished product is significantly improved.

[0034] 3. This invention provides three parallel technical solutions: gradient activation, high-efficiency activation, and activation loop control flow, each applicable to materials with different grindability characteristics. Users can choose flexibly according to actual working conditions, making it widely applicable. Attached Figure Description

[0035] Figure 1 This is a discrete element method simulation of the material velocity distribution inside a traditional ball mill. Figure 2 This is a diagram showing the structural parameters of the gradient activation scheme provided in Embodiment 1 of the present invention; Figure 3 yes Figure 2BB section view; Figure 4 yes Figure 2 Enlarged detail of part A in the middle; Figure 5 This is a structural parameter diagram of the potent activation scheme provided in Embodiment 2 of the present invention; Figure 6 yes Figure 5 CC cross-section; Figure 7 yes Figure 5 Enlarged detail of section D in the middle; Figure 8 yes Figure 5 Enlarged detail of part E in the middle; Figure 9 yes Figure 5 Enlarged detail of part F in the middle; Figure 10 This is a structural parameter diagram of the activated loop flow control scheme provided in Embodiment 3 of the present invention; Figure 11 yes Figure 10 GG cross-section; Figure 12 yes Figure 11 Partial cross-sectional view of section II; Figure 13 yes Figure 11 A partial cross-sectional view of HH; Figure 14 yes Figure 13 Central J-direction view; Figure 15 The working principle of the gradient activation scheme provided in this embodiment of the invention is simulated using EDEM. Figure 1 ; Figure 16 The working principle of the gradient activation scheme provided in this embodiment of the invention is simulated using EDEM. Figure 2 ; Figure 17 This is an EDEM simulation diagram of the working principle of the activated loop control flow scheme provided in Embodiment 3 of the present invention; Figure 18 This is a geometric model diagram of the gradient activation scheme for a Φ1.4×7.0m semi-industrial test mill; Figure 19 This is a geometric model diagram of the high-efficiency activation scheme for a Φ1.4×7.0m semi-industrial test mill; Figure 20 Different gradient activation schemes under the same conditions Material velocity-time curve at the outlet of an angle mill; Figure 21 Different gradient activation schemes under the same conditions Torque-time curve of the cylinder of the angle mill.

[0036] Figure label: 1. Mill cylinder; 2. Support liner fastening bolts; 3. Coarse grinding chamber liner; 4. Grinding chamber liner fastening bolts; 5. Mill inlet; 6. Gradient activation module; 7. Coarse grinding chamber; 8. Partition plate; 9. Fine grinding chamber; 10. Support liner; 10-1. Embedded section; 10-2. Support section; 11-1. First support ring plate; 11-2. Second support ring plate; 12. Fine grinding chamber liner; 13. Gradient activation blades; 14. Grinding grate; 15. Wear-resistant guard plate. 16. Bolts and nuts; 17. Mill feed chute; 18. High-efficiency activation module; 19. High-efficiency activation blade; 20. Blade support ball bearing; 21. Blade positioning seat; 22. Bearing seat; 22-1. Bearing seat A; 22-2. Bearing seat B; 23. Adjustment hole; 24. U-groove; 25. Flow control activation module; 26. Activation ring; 27. Flow control activation blade; 28. Flow passage plate; 29. ​​Blade support rib; 30. Mill outlet. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments and accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0038] Techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of exemplary embodiments may have different values.

[0039] The accompanying drawings of this invention are all in a very simplified form and use non-precise proportions, intended only to facilitate and clarify the illustration of the embodiments of this invention, and are not intended to limit the implementation of this invention. Any changes to the proportions or adjustments to the size of any structure, without affecting the effects and objectives achieved by this invention, should fall within the scope of the technical content disclosed in this invention. Furthermore, the same reference numerals appearing in the various drawings of this invention represent the same features or components, and can be applied to different embodiments.

[0040] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0041] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connection," "linking," and "installation" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0042] Example 1 Please see Figures 2-4 This embodiment provides a material zone activation device for a ball mill, specifically a material zone activation device employing gradient activation.

[0043] The ball mill in this embodiment includes a mill body 1, and a mill inlet 5 and a mill outlet 30 located at opposite ends of the mill body 1. Along the direction from the mill inlet 5 to the mill outlet 30, the mill body 1 is sequentially divided into a coarse grinding chamber 7 and a fine grinding chamber 9. A partition plate 8 is provided between the coarse grinding chamber 7 and the fine grinding chamber 9. Grinding chamber liners are respectively installed on the inner walls of the coarse grinding chamber 7 and the fine grinding chamber 9. The grinding chamber liners are fixed to the mill body 1 by grinding chamber liner fastening bolts 4. A coarse grinding chamber liner 3 is installed on the inner wall of the coarse grinding chamber 7, and a fine grinding chamber liner 12 is installed on the inner wall of the fine grinding chamber 9. A mill feed chute 17 is provided at the mill inlet 5 for conveying the material to be ground into the mill. A grinding grate 14 is provided at the inner end of the mill body 1 near the mill outlet 30 for separating the grinding media and the finished material.

[0044] The material zone activation device in this embodiment includes at least one gradient activation module 6 disposed in the coarse grinding chamber 7 and the fine grinding chamber 9, and rotates synchronously with the mill cylinder 1. When multiple gradient activation modules 6 are provided, the gradient activation modules 6 are arranged in sections within the mill cylinder 1. Each gradient activation module 6 has at least one activation element extending into the dead material zone within the mill, which is a gradient activation blade 13. The gradient activation blade 13 is used to forcibly agitate the material in the dead material zone within the mill, constructing a radial activation velocity difference to achieve radial activation of the material in the dead material zone. Here, the dead material zone refers to the low-speed zone located below the material surface within the mill cylinder 1, where the relative velocity difference between the material and the grinding media is small or zero, resulting in low grinding efficiency. The gradient activation blade 13 is inclined in the circumferential direction of the mill against the material flow direction, and is used to generate a counter-thrust force against the material flow direction during rotation, thereby prolonging the residence time of the material within the mill.

[0045] Specifically, the gradient activation module 6 includes two first support ring plates 11-1 and several gradient activation blades 13 evenly distributed between the two first support ring plates 11-1. A certain distance is maintained between the first support ring plates 11-1, the gradient activation blades 13, and the corresponding grinding chamber liners. The ratio of the length of a single gradient activation blade 13 in the coarse grinding chamber to the effective length of the coarse grinding chamber is 0.11~0.41, and the ratio of the length of a single gradient activation blade 13 in the fine grinding chamber to the effective length of the fine grinding chamber is 0.05~0.16. The ratio of the inner diameter of the first support ring plate to the effective inner diameter of the mill cylinder is 0.65~0.85, and the ratio of the outer diameter of the first support ring plate to the effective inner diameter of the mill cylinder is 0.7~0.9. The gradient activation blades 13 are welded to the first support ring plates 11-1, the support ring plates 11 are fixed to the support assembly, and the support assembly is fixed to the mill cylinder 1.

[0046] In this embodiment, the support assembly includes a support liner 10, which is fixed to the mill cylinder 1 by support liner fastening bolts 2, and the first support ring plate 11-1 is fixed to the support liner 10 by bolts and nuts 16.

[0047] Specifically, the support liner 10 has an "L"-shaped structure, divided into an inlay section 10-1 and a support section 10-2. The inlay section 10-1 has the same structure as the coarse grinding chamber liner 3 and the fine grinding chamber liner 12, and is evenly inlaid and fixed to the mill cylinder 1 using support liner fastening bolts 2, and is flush with the grinding chamber liner (coarse grinding chamber liner 3 or fine grinding chamber liner 12) in the corresponding grinding chamber; the support section 10-2 extends towards the center of the mill and is used to support and fasten the gradient activation module 6 inside the mill. The first support ring plate 11-1 is fixed to the support section 10-2 by bolts and nuts 16.

[0048] To facilitate installation inside the mill, the gradient activation blades 13 adopt a circumferentially distributed, axially segmented combination structure, and are installed and fastened to the support section 10-2 in segments inside the mill. The support liner 10 is preferably cast from wear-resistant cast steel, which has high strength and good wear resistance. To prevent the bolts and nuts 16 from wearing off, wear-resistant sleeves 15 are designed at both ends of the bolts and nuts 16, which can be welded or cast together with the fastened components (in this case, the support liner 10).

[0049] In this embodiment, the angle between the gradient activation blade 13 and the radial direction of the mill is... The angle between the gradient activation blade 13 and the mill axis is 25°~35°. The range is 20° to 40°, which improves the adaptability and maintainability of the device.

[0050] The gradient activation blade 13 can be a straight plate or a spiral curved plate; when it is a spiral curved plate, the end face profile of any point on the curved plate has an angle with the radial direction of the mill. The angle between the contour normal of any point on the curved panel and the mill axis is 25°~35°. The range is 20° to 40°.

[0051] The gradient activation process is briefly described as follows: Driven by the mill drive unit, the gradient activation module 6 inside the mill rotates along with the mill cylinder 1. The material to be ground enters the coarse grinding chamber 7 via the mill feed chute 17 under gravity. Then, driven by the rotating mill cylinder 1, it is carried upwards to a certain height by the coarse grinding chamber liner 3 and then slides downwards; simultaneously, it flows along the mill axis towards the mill outlet 30. Upon reaching the gradient activation module 6 inside the coarse grinding chamber 7, it is forcibly agitated by the gradient activation blades 13 of the gradient activation module 6. Figure 1 The material in zone B, as shown, creates a radial velocity difference in the material balls within zone B, achieving radial activation of the dead material zone. On the other hand, the material balls are carried upwards to a higher height by the gradient activation blades 13, increasing the radial kinetic potential energy of the material balls. Furthermore, in this embodiment, the gradient activation blades 13 of the gradient activation modules 6 at the beginning of each bin can be arranged with their rotation direction aligned with the material flow direction within the mill to prevent backflow at the mill inlet. The gradient activation blades 13 of the gradient activation modules 6 at the end can be arranged with their rotation direction aligned against the material flow direction within the mill. The gradient activation blades 13 of the remaining gradient activation modules 6 can be arranged alternately with their rotation directions aligned in both directions. This alternating arrangement of forward and reverse rotation can create a radial structure along the mill's axial direction. Figure 3The axial "counter-flow" impact grinding effect shown further improves grinding efficiency and achieves axial gradient activation of the dead material zone. Alternatively, the gradient activation blades 13 of the gradient activation modules 6 at the beginning of each chamber can be arranged with their rotation direction in the direction of material flow within the mill, while the gradient activation blades 13 of the remaining gradient activation modules 6 can be arranged with their rotation direction in the direction of material flow within the mill; or other situations may be considered. In specific implementation, adjustments can be made according to changes in the grindability index of the material and the actual working conditions. In this way, driven by the material level difference between the inlet and outlet of the mill and the rotation of the mill, the material to be ground passes sequentially through the coarse grinding chamber 7, the partition plate 8, the fine grinding chamber 9 and its respective gradient activation modules 6, the outlet grate 14, and finally exits the mill through the mill outlet 30, completing the grinding of the material.

[0052] The main process parameters involved in the gradient activation device are as follows: Mill Design Output (t / h), theoretical power consumption per unit product (kWh / t), theoretical power of mill (kW), nominal diameter of mill (mm), nominal length of mill (mm), mill cylinder thickness (mm), mill length-to-diameter ratio Mill filling rate Grinding media density (t / m 3 Mill energy density (kW / t), thickness of mill liner or thickness of the inlay section of support liner 10 (mm), effective inner diameter of mill (mm), effective length of mill (mm), effective length of coarse grinding chamber (mm), effective length of fine grinding chamber (mm), distance from the gradient activation module 6 at the beginning of the coarse grinding chamber 7 to the inner wall of the grinding head. (mm), distance from the end gradient activation module 6 inside the coarse grinding chamber 7 to the partition plate 8 (mm), the spacing between two adjacent gradient activation modules 6 within the coarse grinding chamber 7 (mm), distance from the gradient activation module 6 at the beginning of the fine grinding chamber 9 to the partition plate 8 (mm), distance from the end gradient activation module 6 inside the fine grinding chamber 9 to the grinding grate 14 (mm), the spacing between two adjacent gradient activation modules 6 within the fine grinding chamber 9 (mm), the angle between the gradient activation blade 13 and the mill radial direction. ( The angle between the gradient activation blade 13 and the mill axis ( ), the circumferential angle between two adjacent gradient-activated leaves 13 ( ), length of gradient activated leaf 13 (mm), width of gradient activated leaf 13 (mm), the radial clearance between the first support ring plate 11-1 and the inner wall of the corresponding grinding chamber liner plate. (mm), the radius of curvature of the inlay section of the support liner is 10-1. (mm), Length of the inlay section of the bracket liner (mm), outer diameter arc length of the inlay section of the bracket liner (mm), height of the support section 10-2 of the bracket liner. (mm), thickness of the support section of the bracket liner (mm), Thickness of the first support ring plate 11-1 (mm), Gradient activated leaf thickness 13 (mm), Inner diameter of the first support ring plate (mm), outer diameter of the first support ring plate (mm), Number of gradient activation modules 6 inside the coarse grinding chamber 7 (units), the number of gradient activation modules 6 inside the fine grinding chamber 9 (units), the number of gradient activation leaves 13 contained in each gradient activation module 6 (indivual).

[0053] 1) Based on the mill's designed output (t / h), theoretical power consumption per unit product (kWh / t), power reserve factor Calculate the theoretical power of the mill (kW): (1) Power reserve factor The value is generally taken as 1.15~1.2.

[0054] 2) Based on the length-to-diameter ratio of the mill Mill filling rate Grinding media density (t / m 3 Mill energy density (kW / t), calculate the effective inner diameter of the mill (mm): (2) Mill length-to-diameter ratio = 3~5; Mill filling rate =0.25~0.35; Grinding media bulk density =4.0~5.5 t / m 3 Mill energy density =10~14 kW / t.

[0055] 3) Effective length of the mill (mm): (3) 4) Nominal diameter of the mill (mm) and nominal length of the mill (mm): (4) (5) For the newly designed mill, the nominal diameter of the mill is calculated according to formulas (4) and (5). Nominal length of mill After rounding, the mill specifications are determined, and then based on the determined specifications... , The final effective inner diameter of the mill was determined by adjusting the mechanical design parameters of the mill liners, partition plates, and discharge grate. Effective length of grinding mill For old mills, take the actual value of the mill. , Numerical value.

[0056] 5) Effective length of the coarse grinding chamber (mm), effective length of fine grinding chamber (mm): (6) (7) For newly designed mills, the effective length of the coarse grinding chamber is determined according to the values ​​calculated by formulas (6) and (7). L 1. Effective length of the fine grinding chamber L 2; For old mills, determine the effective length of the coarse grinding chamber. L 1. Effective length of the fine grinding chamber L 2. The actual value is sufficient. If the actual value deviates from the calculation results of formula (6) and (7), the effective length of the coarse grinding chamber 7 and fine grinding chamber 9 of the mill needs to be adjusted according to the calculation values ​​of formula (6) and (7).

[0057] 6) Number of gradient activation modules in coarse grinding chamber 7 (units), number of gradient activation modules in fine grinding chamber 9 (indivual): (8) (9) in, =250~500mm, =150~250mm, =150~250mm, =150~250mm, =400~800mm, =400~800mm.

[0058] 7) Mill cylinder thickness (mm), the radius of curvature of the inlay section of the support liner is 10-1. (mm), thickness of the inlay section of the bracket liner (mm), Length of the inlay section of the bracket liner (mm), outer diameter arc length of the inlay section of the bracket liner (mm), Height of the support section 10-2 of the bracket liner (mm), thickness of the support section of the bracket liner (mm), center angle of bracket liner ( ): (10) (11) (12) (13) (14) (15) (16) (17) The number of all liners (including support liners and grinding chamber liners) in the circumferential direction of the mill. =20~50.

[0059] 8) The radial clearance between the first support ring plate 11-1 and the inner wall of the corresponding grinding chamber liner. (mm), Inner diameter of the first support ring plate (mm), outer diameter of the first support ring plate (mm), thickness of the first support ring plate (mm): (18) (19) (20) (twenty one) 9) Calculate the angle between the gradient activation blade 13 and the mill radial direction. ( The angle between the gradient activation blade 13 and the mill axis ( ), the circumferential angle between two adjacent gradient-activated leaves ( The number of gradient activation blades contained in each gradient activation module. (number) Length of gradient-activated leaves (mm), width of gradient activated blades (mm), thickness of gradient activated blades (mm): (twenty two) (twenty three (twenty four) (25) (26) (27) (28) Gradient activation primarily focuses on activating the dead material zone, supplemented by controlling the residence time within the mill. The gradient activation blades 13 forcibly agitate the material in the dead material zone, creating a radial activation velocity difference that effectively disrupts the dead material zone. Simultaneously, the alternating clockwise and counter-clockwise rotation of the blades creates an axial collision velocity difference, extending the material residence time. This embodiment is suitable for moderately grindable materials, especially hard and brittle materials that are "easy to grind but difficult to crush" (material grindability index of 14~20 kWh / t, T). 3000 =35~45min).

[0060] Example 2 Please see Figures 5-9 This embodiment provides another material zone activation device for a ball mill, specifically a material zone activation device employing high-efficiency activation.

[0061] This embodiment has a basically the same overall structure as Embodiment 1, including components such as mill cylinder 1, mill inlet 5, mill outlet 30, coarse grinding chamber 7, fine grinding chamber 9, partition plate 8, coarse grinding chamber liner 3, fine grinding chamber liner 12, mill feed chute 17, and mill grate 14. The main difference lies in the structure of the activation module.

[0062] The material zone activation device in this embodiment includes at least one high-efficiency activation module 18 respectively disposed in the coarse grinding chamber 7 and the fine grinding chamber 9, and rotates synchronously with the mill cylinder 1. When multiple high-efficiency activation modules 18 are provided, the high-efficiency activation modules 18 are arranged in sections within the mill cylinder 1. Each high-efficiency activation module has at least one activation element extending into the dead material zone inside the mill, which is a high-efficiency activation blade 19. The high-efficiency activation blade 19 is used to forcibly agitate the material in the dead material zone inside the mill, constructing a radial activation speed difference to achieve radial activation of the material in the dead material zone. The high-efficiency activation blade 19 is inclined in the circumferential direction of the mill against the material flow direction, and is used to generate a reverse thrust against the material flow direction when rotating, thereby prolonging the residence time of the material in the mill.

[0063] Specifically, the high-efficiency activation module 18 includes two second support ring plates 11-2 and several high-efficiency activation blades 19 evenly distributed between the two second support ring plates 11-2. A certain distance is maintained between the second support ring plates 11-2, the high-efficiency activation blades 19, and the corresponding grinding chamber liners. The ratio of the length of a single high-efficiency activation blade 19 in the coarse grinding chamber to the effective length of the coarse grinding chamber is 0.22~0.85, and the ratio of the length of a single high-efficiency activation blade 19 in the fine grinding chamber to the effective length of the fine grinding chamber is 0.1~0.42. The ratio of the inner diameter of the second support ring plate to the effective inner diameter of the mill cylinder is 0.65~0.85, and the ratio of the outer diameter of the second support ring plate to the effective inner diameter of the mill cylinder is 0.7~0.9. The high-efficiency activation blades 19 are connected to the second support ring plates 11-2, which are fixed to the support assembly, which is fixed to the mill cylinder 1.

[0064] In this embodiment, the support assembly includes a support liner 10, which is fixed to the mill cylinder 1 by support liner fastening bolts 2, and the second support ring plate 11-2 is fixed to the support liner 10 by bolts and nuts 16.

[0065] Specifically, the support liner 10 has an "L"-shaped structure, divided into an inlay section 10-1 and a support section 10-2. The inlay section 10-1 has the same structure as the coarse grinding chamber liner 3 and the fine grinding chamber liner 12, and is evenly inlaid and fixed to the mill cylinder 1 using support liner fastening bolts 2, and is flush with the grinding chamber liner (coarse grinding chamber liner 3 or fine grinding chamber liner 12) in the corresponding grinding chamber; the support section 10-2 extends towards the center of the mill and is used to support and fasten the high-efficiency activation module inside the mill. The second support ring plate 11-2 is fixed to the support section 10-2 by bolts and nuts 16.

[0066] To facilitate installation inside the mill, the high-efficiency activation blades 19 adopt a circumferentially distributed, axially segmented combination structure, and are installed and fastened to the support section 10-2 in segments inside the mill. The support liner 10 is preferably cast from wear-resistant cast steel, which has high strength and good wear resistance. To prevent the bolts and nuts 16 from wearing off, wear-resistant sleeves 15 are designed at both ends of the bolts and nuts 16, which can be welded or cast together with the fastened components (in this case, the support liner 10).

[0067] Both ends of the highly effective activating blade 19 are fixedly installed on the second support ring plate 11-2. Alternatively, one end of the highly effective activating blade 19 is rotatably installed on the second support ring plate 11-2, and the other end is fixedly installed on the second support ring plate 11-2.

[0068] In this embodiment, one end of the high-efficiency activation blade 19 is rotatably mounted on the second support ring plate 11-2, and the other end is fixedly mounted on the second support ring plate 11-2, and the angle of this end on the second support ring plate 11-2 along the circumference of the mill can be adjusted.

[0069] Specifically, one end of the high-efficiency activation blade 19 is rotatably connected to the bearing seat 22 via a blade support ball bearing 20, and the bearing seat 22 is fastened to the second support ring plate 11-2. The other end of the high-efficiency activation blade 19 is fastened to the second support ring plate 11-2 via a blade positioning seat 21. The end of the high-efficiency activation blade fixedly installed on the second support ring plate 11-2 can be adjusted by 0~15° along the circumference of the mill on the second support ring plate 11-2.

[0070] To facilitate the installation and positioning of the high-efficiency activation blade 19, the bearing housing 22 is divided into two parts: bearing housing A 22-1 and bearing housing B 22-2. The blade support ball bearing 20 is first fitted inside bearing housing A 22-1 and bearing housing B 22-2, and then bearing housing A 22-1 and bearing housing B 22-2 are fastened to the second support ring plate 11-2 by bolts and nuts 16, forming a universal rotatable connection at one end (left side) of the high-efficiency activation blade 19. The other end (right side) of the high-efficiency activation blade 19 is connected to the blade positioning seat 21 by bolts and nuts 16, and the blade positioning seat 21 is fastened to the second support ring plate 11-2 by bolts and nuts 16, achieving a fixed installation.

[0071] At the junction of the support ring plate 11 and the blade positioning seat 21, 4 to 6 adjustment holes 23 are designed for blade position adjustment. These holes allow for 0 to 15° circumferential angle adjustment of the right side of the high-efficiency activation blade 19 on the second support ring plate 11-2. To accommodate this angle adjustment, a U-shaped groove 24 for blade position adjustment is designed on the right side of the high-efficiency activation blade 19, and its position is adjustable to the blade positioning seat 21 via bolts and nuts 16. In this embodiment, the angle between the high-efficiency activation blade 19 and the mill radial direction is... The angle between the mill axis and the mill axis is 25°~35°. The range is 20° to 40°, which improves the adaptability and maintainability of the device.

[0072] The highly effective activating blade 19 can be a straight plate or a spiral curved plate; when it is a spiral curved plate, the end face profile of any point on the curved plate has an angle with the radial direction of the mill. The angle between the contour normal of any point on the curved panel and the mill axis is 25°~35°. The range is 20° to 40°.

[0073] The main process parameters involved in the high-efficiency activation device are as follows: Mill Design Output (t / h), theoretical power consumption per unit product (kWh / t), theoretical power of mill (kW), nominal diameter of mill (mm), nominal length of mill (mm), mill cylinder thickness (mm), mill length-to-diameter ratio Mill filling rate Grinding media density (t / m 3 Mill energy density (kW / t), thickness of mill liner or thickness of the inlay section of support liner (mm), effective inner diameter of mill (mm), effective length of mill (mm), effective length of coarse grinding chamber (mm), effective length of fine grinding chamber (mm), the distance between the high-efficiency activation module 18 at the beginning of the coarse grinding chamber 7 and the inner wall of the grinding head. (mm), distance from the end-efficiency activation module 18 inside the coarse grinding chamber 7 to the partition plate 8 (mm), coarse grinding chamber 7 inner high-efficiency activated blade 19 wheelbase (mm), the distance between the high-efficiency activation module 18 at the beginning of the fine grinding chamber 9 and the partition plate 8. (mm), the distance between the end-efficiency activation module 18 inside the fine grinding chamber 9 and the outlet grinding grate 14. mm), fine grinding chamber 9 internal high-efficiency activated blades 19 wheelbase (mm), the wheelbase between two adjacent high-efficiency activation modules 18 (mm), Angle between the high-efficiency activated blade 19 and the mill radial direction ( The angle between the high-efficiency activated blade 19 and the mill axis ( ), the circumferential angle between two adjacent highly effective activating blades ( ), length of the highly effective activated leaf 19 (mm), width of the highly effective activated blade (mm), the distance between the second support ring plate 11-2 and the radial clearance of the inner wall of the grinding chamber liner plate. (mm), the radius of curvature of the inlay section of the support liner is 10-1. (mm), Length of the inlay section of the bracket liner (mm), outer diameter arc length of the inlay section of the bracket liner (mm), height of the support section of the bracket liner (mm), thickness of the support section of the bracket liner (mm), Thickness of the second support ring plate 11-2 (mm), thickness of highly activated blade (mm), Inner diameter of the second support ring plate 11-2 (mm), outer diameter of the second support ring plate 11-2 (mm), Number of high-efficiency activation modules in the coarse grinding chamber (units), number of high-efficiency activation modules in the fine grinding chamber (units), the number of highly activated blades contained in each highly activated module. (unit), diameter of blade support ball bearing (mm), diameter of the journal of the blade support ball bearing (mm), outer diameter of bearing housing (mm), U-groove length (mm), Number of adjustment holes (indivual): 1) Theoretical power of the mill (kW), nominal diameter of mill D (mm), nominal length of mill (mm), effective inner diameter of mill (mm), effective length of mill (mm), effective length of coarse grinding chamber (mm), effective length of fine grinding chamber The calculation method for (mm) is shown in formulas (1) to (7).

[0074] 2) Number of high-efficiency activation modules in the coarse grinding chamber (units), number of high-efficiency activation modules in the fine grinding chamber (indivual): (29) (30) in, =250~500mm, =150~250mm, =150~250mm, =150~250mm, =250~500mm, =1500±500mm, =1500±500mm.

[0075] 3) Mill cylinder thickness (mm), radius of curvature of the bracket liner inlay section 10-1 (mm), the thickness of the inlay section of the bracket backing plate is 10-1. (mm), Length of the 10-1 inlay section of the bracket backing plate (mm), circumferential arc length of the inlay section of the bracket liner 10-1 (mm), Height of the support section 10-2 of the bracket liner (mm), thickness of bracket liner support section 10-2 (mm), center angle of bracket liner ( The calculation method for ) is shown in formulas (10) to (17).

[0076] 4) The distance between the second support ring plate 11-2 and the radial clearance of the inner wall of the grinding chamber liner. (mm), Inner diameter of the second support ring plate 11-2 (mm), outer diameter of the second support ring plate 11-2 (mm), Thickness of the second support ring plate 11-2 (mm): (31) (32) (33) (34) 5) The angle between the high-efficiency activated blade 19 and the mill radial direction ( ), The angle between the blades and the mill axis for effective activation ( ), the circumferential angle between two adjacent highly effective activating blades ( ), effectively activate leaf thickness (mm), Number of high-efficiency activation blades in each high-efficiency activation module (each), length of the highly effective activated leaf (mm), width of the highly effective activated blade (mm): (35) (36) (37) (38) (39) (40) (41) 5) Calculate the diameter of the blade support ball bearing (mm), diameter of the journal of the blade support ball bearing (mm), outer diameter of bearing housing (mm), U-groove length (mm), Number of adjustment holes (indivual): (42) (43) (44) (45) (46) The enhanced activation process is briefly described as follows: The mill drive unit drives the mill cylinder 1 and the enhanced activation module inside the mill to rotate together. The material to be ground enters the coarse grinding chamber 7 under the action of gravity through the mill feed chute 17, and is then lifted to a certain height by the coarse grinding chamber liner 3, which rotates with the mill cylinder 1, before sliding down and flowing towards the mill outlet 30. After moving to the enhanced activation module 18 inside the mill, the material in the dead zone is forcibly stirred by the enhanced activation blades 19, creating a radial velocity difference in the mill and achieving radial activation of the dead zone; because the enhanced activation blades 19 are at a certain angle against the flow direction of the material inside the mill, while forcibly stirring the material, they generate a reverse thrust on the material in the direction of the material flow inside the mill, reducing the material flow velocity inside the mill and prolonging the residence time of the material inside the mill. In this repeated process, driven by the material level difference between the inlet and outlet of the mill and the rotation of the mill cylinder 1, the material to be ground passes through the coarse grinding chamber 7, the partition plate 8, the fine grinding chamber 9 and its various high-efficiency activation modules 18, and the mill grate 14 in sequence, and finally exits the mill through the mill outlet 30, thus completing the grinding of the material.

[0077] The intensive activation method is based on "dual control of dead material zone activation and residence time throughout the mill." Through the forced stirring of the intensive activation blades 19, a radial velocity difference is created within the mill, achieving radial activation of the dead material zone. Simultaneously, because the intensive activation blades 19 are tilted at a certain angle against the material flow direction within the mill, they generate a reverse thrust on the material while forcibly stirring it, reducing the material flow velocity and extending the residence time. The relatively long length of the intensive activation blades 19 enables almost full-axial flow control and activation of the mill. This embodiment is suitable for difficult-to-grind materials, especially those with the characteristic of being "easy to crush but difficult to grind" (material grindability index ≤ 14 kWh / t, T). 3000 =45~55min).

[0078] Example 3 Please see Figures 10-14 This embodiment provides another material zone activation device for a ball mill, specifically a material zone activation device that employs activation loop control flow.

[0079] This embodiment has a basically the same overall structure as Embodiment 1, including components such as mill cylinder 1, mill inlet 5, mill outlet 30, coarse grinding chamber 7, fine grinding chamber 9, partition plate 8, coarse grinding chamber liner 3, fine grinding chamber liner 12, mill feed chute 17, and mill grate 14. The main difference lies in the structure of the activation module.

[0080] The material zone activation device in this embodiment includes at least one flow-controlled activation module 25 disposed in the coarse grinding chamber 7 and the fine grinding chamber 9, respectively. Each flow-controlled activation module 25 has at least one activation element extending into the dead material zone inside the mill. The activation element includes an activation ring 26, flow-controlled activation blades 27, and a flow-through perforated plate 28. The flow-through perforated plate 28 and the flow-controlled activation blades 27 are alternately arranged circumferentially on the activation ring 26. The flow-through perforated plate 28 is disposed inside the activation ring 26 and has a porous structure for allowing some material to pass through. The porosity of the flow-through perforated plate is 15-35%. The flow-controlled activation blades 27 are disposed on the activation ring 26 and are inclined against the material flow direction inside the mill. The angle between the flow-controlled activation blades and the activation ring is... The angle is 15° to 45°. To enhance the structural strength of the flow-controlled activation blade, a blade support rib 29 can be provided between the flow-controlled activation blade 27 and the activation ring 26. The activation ring 26 is fixed on the support assembly, and the support assembly is fixed on the mill cylinder.

[0081] In this embodiment, the support assembly includes a support liner 10, which is fixed to the mill cylinder 1 by support liner fastening bolts 2, and the activation ring 26 is fixed to the support liner 10 by bolts and nuts 16.

[0082] Specifically, the support liner 10 has an "L"-shaped structure, divided into an inlay section 10-1 and a support section 10-2. The inlay section 10-1 has the same structure as the coarse grinding chamber liner 3 and the fine grinding chamber liner 12, and is evenly inlaid and fixed to the mill cylinder 1 using support liner fastening bolts 2, and is flush with the grinding chamber liner (coarse grinding chamber liner 3 or fine grinding chamber liner 12) in the corresponding grinding chamber; the support section 10-2 extends towards the center of the mill and is used to support and fasten the activation ring inside the mill. The activation ring 26 is fixed to the support section 10-2 by bolts and nuts 16.

[0083] The activation ring flow control process is briefly described as follows: The mill drive unit drives the mill cylinder 1 and the flow control activation module 25 to rotate together. The material to be ground enters the coarse grinding chamber 7 through the mill feed chute 17 under the action of gravity. Then, it is lifted to a certain height by the coarse grinding chamber liner 3, which rotates with the mill cylinder 1, and then slides down, while flowing towards the mill outlet 30. After moving to the flow control activation module 25 inside the mill, it is first lifted to a higher height by the flow control activation blades 27 installed on the activation ring 26, forming a radial activation velocity difference, increasing the impact crushing effect of the material balls inside the mill, and realizing the radial activation of the material in the dead material zone; at the same time, it pushes the lifted material back against the mill discharge direction, reducing the material flow velocity, prolonging the material residence time in the mill, and improving the mill's fine grinding capacity. In this repeated process, driven by the material level difference between the inlet and outlet of the mill and the rotation of the mill cylinder 1, the material to be ground passes through the coarse grinding chamber 7, the partition plate 8, the fine grinding chamber 9 and its respective flow control activation modules 25, the mill grate 14, and finally exits the mill through the mill outlet 30, thus completing the grinding of the material.

[0084] The activated ring flow control scheme primarily focuses on controlling the residence time within the mill, while also activating the dead material zone. The flow control activation blades 27 lift the material to a higher height, creating a radial activation velocity difference to achieve radial activation of the material in the dead material zone. Simultaneously, because the flow control activation blades 27 are tilted at a certain angle against the material flow direction within the mill, a reverse force is applied to the lifted material, reducing the material flow velocity and extending the residence time. The porous structure of the flow perforated plate 28 ensures good ventilation and material flow within the mill, avoiding the risk of blockage. This embodiment is suitable for materials with good grindability (grindability index ≤ 14 kWh / t, T...). 3000 =35~45min).

[0085] To facilitate a clearer and more intuitive explanation of the working principle of this invention, EDEM discrete element simulation was used. Taking a Φ3.8x13m industrial ball mill as the research object, EDEM discrete element simulation was performed on the above-mentioned gradient activation scheme and activation loop control flow scheme. The simulation results are shown below. Figures 15-17 .

[0086] Comparison of simulation results with the non-grinding internal activation device Figure 1 The present invention through Figure 1The B zone shown is equipped with internal activated blades that rotate with the mill cylinder, which forcibly agitate the material in the B zone (grinding media + material to be ground), increasing the velocity gradient of the material in the B zone. This not only eliminates the dead material zone and improves the "shearing" grinding effect between the material balls, but also increases the lifting degree of the material and the kinetic energy of the material when it falls to the bottom of the mill, thus improving the "impact" crushing effect between the materials.

[0087] Along the mill's axial direction, material enters the mill from the left-side feed chute. Driven by the mill cylinder, it is simultaneously carried upwards by the rotating cylinder, along with the grinding media inside, to a certain height before sliding to the bottom of the cylinder. Furthermore, due to the difference in material levels at the mill's inlet and outlet, it moves from the left-side feed end towards the discharge end. For Figure 15 and Figure 16 The gradient activation scheme shown first agitates the material and grinding media in the dead zone within the mill, creating a velocity difference between the grinding media and disrupting the "dead zone" where the grinding media move at the same velocity, thus increasing the shearing and grinding effect. Secondly, by setting two sets of activation blades with different rotational directions within the mill, a further agitation is achieved. Figure 16 The "collision arrows" in the middle indicate the axial "counter-flow" collision speed difference impact grinding effect of the mill, which achieves the control of material residence time in the mill while improving the mill's fine grinding capacity and grinding efficiency. For Figure 17 The activated ring flow control scheme shown in the diagram first lifts the material to a higher height by the flow control activation blades installed on the activated ring after it moves to the activated ring, thereby increasing the impact crushing effect of the material balls in the mill. At the same time, it pushes the material back in the opposite direction of the mill discharge (red dashed arrow) (black solid arrow), thereby extending the residence time of the material in the mill and improving the mill's fine grinding capacity.

[0088] In summary, this invention addresses the common problems of "dead material zone" within ball mills and the limited means of adjusting material residence time. Its working principle is as follows: The material to be ground enters the coarse grinding chamber 7 under gravity through the mill feed inlet 17. The mill's material zone activation device (gradient activation, high-efficiency activation, and activation ring flow control) rotates along with the mill cylinder 1 under the drive of the drive device, thus... Figure 1The material in zone B flows at different speeds and directions, increasing the relative velocity between the material and the grinding media, disrupting the "dead material zone," enhancing the "shearing" grinding effect, reducing the mill's wasted energy consumption, and improving the mill's grinding efficiency. Furthermore, because the activation blades of the material zone activation device are tilted at a certain angle against the material flow direction within the mill, while driving the material's radial activation movement, the activation blades also generate a counter-force against the material flow direction, increasing the material's residence time within the mill and further enhancing the mill's fine grinding capacity and grinding efficiency. The mill's material zone activation device fundamentally disrupts the dead material zone within the mill, reducing the mill's wasted energy consumption, and extends the material's residence time within the mill, solving the problem of limited means of adjusting the material's residence time within the mill, thus significantly improving the ball mill's fine grinding capacity and grinding efficiency.

[0089] To verify the technical effectiveness of the activation scheme of this invention, a Φ1.4×7.0m semi-industrial test mill was used as the object. A combination of EDEM discrete element simulation and experimental research was employed to study the technical effects of different activation schemes. The activation loop control scheme in Example 3 primarily focuses on controlling the residence time within the mill, while also considering activation of the dead material zone. This scheme has been fully disclosed in Example 3. The following only describes the verification results of the gradient activation scheme and the high-efficiency activation scheme, as detailed below: 1. Main structural parameters of the mill Nominal diameter of mill =1400mm, grinding chamber liner thickness =50mm, effective inner diameter of the mill =1300mm, effective length of the mill =6750mm, effective length of the coarse grinding chamber =1450mm, effective length of fine grinding chamber =5300mm.

[0090] 2. Main structural parameters of different activation schemes 1) Gradient activation scheme The distance between the gradient activation module 6 at the beginning of the coarse grinding chamber 7 and the inner wall of the grinding head. =350mm, the distance between the end gradient activation module 6 and the partition plate 8 inside the coarse grinding chamber 7. =250mm, the spacing between two adjacent gradient activation modules 6 within the coarse grinding chamber 7 =750mm, the distance between the gradient activation module 6 at the beginning of the fine grinding chamber 9 and the partition plate 8. =250mm, the distance between the end gradient activation module 6 inside the fine grinding chamber 9 and the outlet grinding grate 14. =250mm, the spacing between two adjacent gradient activation modules 6 within the fine grinding chamber 9 =400mm, the radial clearance between the first support ring plate 11 and the corresponding grinding chamber liner plate. =200mm, inner diameter of the first bracket ring plate =550mm, outer diameter of the first bracket ring plate =900mm, the number of gradient activation modules 6 in the coarse grinding chamber 7 =2, the number of gradient activation modules 6 inside the fine grinding chamber 9 =7.

[0091] 2) High-efficiency activation solution The distance between the high-efficiency activation module 18 at the beginning of the coarse grinding chamber 7 and the inner wall of the grinding head. =350mm, the distance between the end-efficiency activation module 18 inside the coarse grinding chamber 7 and the partition plate 8 =250mm, the distance between the high-efficiency activation module 18 at the beginning of the fine grinding chamber 9 and the partition plate 8 =250mm, the distance between the end-efficiency activation module 18 inside the fine grinding chamber 9 and the outlet grinding grate 14. =250mm, coarse grinding chamber 7, highly activated blades, 19mm wheelbase =1000mm, fine grinding chamber 9, internal high-efficiency activated blades 19, wheelbase =1500mm, the wheelbase between two adjacent high-efficiency activation modules 18 =250mm, Number of high-efficiency activation modules in the coarse grinding chamber =1, the number of high-efficiency activation modules in the fine grinding chamber =3, the distance between the second support ring plate 11-2 and the radial clearance of the inner wall of the grinding chamber liner is 3. =200mm, inner diameter of the second support ring plate 11-2 =550mm, outer diameter of the second support ring plate 11-2 =900mm.

[0092] Table 1 Blade parameters for the gradient activation scheme and intensive activation scheme of the Φ1.4×7.0m semi-industrial test mill

[0093] 3. Geometric physical model Based on the manufacturing drawings of the Φ1.4×7.0m semi-industrial test mill, the main structural process parameters of the mill, and the main structural parameters of different activation schemes, a geometric model was constructed at a 1:1 scale using 3D modeling software. The 3D geometric models of the gradient activation scheme and the high-efficiency activation scheme are shown below. Figure 18 , Figure 19 As shown. The physical model uses the Hertz-Mindlin contact model and the Tabares fracture model from the EDEM discrete element software.

[0094] 4. Calculate boundary conditions The feed rate is 2.5 kg / s, the particle size of the material entering the mill is ø8 mm, and the mill speed is 27 r / min.

[0095] Table 2. Theoretical Study on Grinding Media Grading in a Φ1.4×7.0m Semi-Industrial Test Mill

[0096] 5. Calculation Results and Technical Effect Analysis Table 3 Different gradient activation schemes EDEM simulation data of residence time of material in coarse grinding chamber under angle

[0097] Note: "Residence time in the mill" in this table refers to the time required for the material to enter and exit the coarse grinding chamber to reach equilibrium.

[0098] Table 4 Different gradient activation schemes EDEM simulation data of angle mill output and main unit power consumption

[0099] According to Table 3 and Table 4, Figure 20 , Figure 21 The simulation results show that the technical effectiveness of this invention is mainly reflected in two aspects: the residence time of materials inside the mill and the power consumption of the main unit. Firstly, regarding the residence time of materials inside the mill, it is significantly increased compared to the scheme without activated blades. Angle from 15 ~35 The minimum increase in residence time of materials in the coarse grinding chamber was 17.11%, and the maximum increase was 101.97%, which prolonged the residence time of materials in the mill and increased the grinding probability of materials in the mill, providing an important guarantee for improving the fine grinding capacity of the mill. Secondly, in terms of main unit power consumption, compared with the scheme without activated blades, the main unit power consumption of finished materials with a particle size <0.045mm was reduced by a maximum of 31.489-18.394=13.095 kWh / t and a minimum of 31.489-27.945=3.544 kWh / t, a reduction of 11.3%~41.6%. Therefore, the grinding efficiency of the ball mill was significantly improved. The power consumption of semi-finished materials with a particle size <0.1mm was reduced by a maximum of 18.933-15.885=3.048 kWh / t and a minimum of 18.933-17.138=1.795 kWh / t, a reduction of 9.5%~16.1%. The power consumption reduction of finished products with a particle size of <0.045mm is much greater than that of semi-finished products with a particle size of <0.1mm, which also proves the original design intention of this invention to solve the "dead material zone" in the mill, improve the material-ball "shear" grinding effect in the mill, and enhance the grinding efficiency of fine particles.

[0100] Table 5. EDEM simulation data of material residence time in the mill for different activation schemes.

[0101] Note: "Residence time in the mill" in this table refers to the time it takes for the material to enter and exit the entire mill in a balanced manner (coarse grinding chamber + fine grinding chamber).

[0102] Based on the simulation data of material residence time in the mill for different activation schemes in Table 5, compared with the scheme without activated blades, the residence time in the mill for both gradient activation and strong activation schemes is significantly improved. Compared with the increase in residence time in the coarse grinding chamber of the gradient activation scheme shown in Table 3, it is lower. The main reason is that as the grinding process proceeds, the material in the fine grinding chamber of the mill becomes finer and has better flowability, resulting in the total increase in residence time in the mill for "coarse grinding chamber + fine grinding chamber" being less than the increase in material residence time in the coarse grinding chamber alone. This further illustrates the necessity of in-mill activation technology.

[0103] 6. Experimental effects of different activation schemes To verify the theoretical and technical effects of different activation schemes and to compare their technical performance, this invention designed and manufactured activation devices for gradient activation and high-efficiency activation schemes based on the main structural parameters of two in-mill activation devices. Extensive experimental research was conducted on a semi-industrial test platform. The test material was the feed material from a TRP140-140-Φ4.2×13m industrial cement combined grinding production system. Five sets of effective repeatable tests were conducted for each activation scheme under the same operating parameters. The average values ​​of the five sets of tests were used to compare the technical effects of different activation schemes, as shown in Tables 7 and 8.

[0104] Table 6. Test data on finished product fineness, specific surface area, and main unit power consumption for different activation schemes.

[0105] Note: In this table, "baseline power consumption" refers to the "grinding surface area" converted to 3200 cm². 2 Comparable power consumption per g of the same specific surface area.

[0106] Table 7 Comparison of test data on finished product performance of different activation schemes

[0107] According to the experimental data in Table 6, under basically the same feed rate, the main unit absorbed power of both the gradient activation scheme and the strong activation scheme decreased compared with the no-activation scheme, by 27.35kW and 41.56kW respectively, representing reductions of 21.9% and 33.3%. This is completely consistent with the phenomenon shown in Table 4, where the mill torque of the gradient activation scheme decreased from 43410.182Nm to 27804.111~29095.946Nm under the same conditions. This verifies the rationality of the simulation calculation data from an experimental perspective, and also verifies the working principle and technical effect of the in-mill activation scheme. Regarding the fineness of the feed and discharge mill particles, the two activation schemes decreased from a similar feed fineness of 40.9-42.2% to a discharge fineness of 9.2-11.1%, which is 10.2-12.1 percentage points lower than the 21.3% discharge fineness of the scheme without activated blades. Regarding the specific surface area of ​​the feed and discharge mill particles, the two activation schemes remained essentially the same, ranging from 2114.2 to 2285.4 cm². 2 The specific surface area per g entering the mill increased to 3332.1~3740.1 cm². 2 / g, compared to 3046.7cm of unactivated leaves 2 The specific surface area of ​​the mill output increased by 285.4~693.4 cm² / g. 2 / g, with a specific surface area increase of 9.4%~22.8%; in terms of baseline power consumption, compared with the unactivated blades, it decreased from 24.31kWh / t to 13.58~15.57kWh / t, a power consumption reduction of 36.0~44.1%, which is basically consistent with the main unit power consumption reduction calculated by simulation in Table 4.

[0108] In terms of finished product performance, according to the data in Table 7, compared with the non-activated blade scheme, the particle uniformity coefficient n value of the gradient activation scheme and the strong activation scheme decreased by 0.084~0.12, the particle sphericity increased by 0.122~0.162, and the standard viscosity water requirement decreased by 1.5~2.1 percentage points; the 3-day strength increased by 2.4~4.3 MPa, an increase of 9.3%~16.6%; and the 28-day strength increased by 2.8~3.4 MPa, an increase of 5.9%~7.1%.

[0109] In comparing different activation schemes, according to the data in Tables 5-7, the high-efficiency activation scheme is the best, superior to the gradient activation scheme, and superior to the activation ring flow control scheme. The different technical effectiveness of each scheme depends on the different degrees of integration of in-mill flow control and activation. The high-efficiency activation scheme achieves almost full-axial flow control and activation of the mill by increasing the length of the activation blades, with the largest increase in in-mill residence time of 37.24%. In contrast, the gradient activation scheme only achieves partial axial flow control and activation of the mill, while the activation ring flow control scheme mainly focuses on flow control with only a small amount of activation effect in the dead material zone. Therefore, the differences in technical effectiveness among different activation schemes are basically consistent with the focus of their respective design principles.

[0110] In summary, this invention fundamentally solves the common problems of "dead material zone" inside the ball mill and the limited means of adjusting material residence time within the mill. Based on theoretical and experimental data, under the same conditions, compared to traditional ball mill technology, the material residence time inside the mill increases by 20%–37%, the main unit power consumption of the finished product decreases by 36–44.1%, the fineness of the material entering and exiting the mill decreases by 10.2–12.1 percentage points, the specific surface area increases by 9.4%–22.8%, the particle uniformity coefficient n value decreases by 0.084–0.12, the particle sphericity increases by 0.122–0.162, the standard consistency water requirement decreases by 1.5–2.1 percentage points, the 3-day strength increases by 2.4–4.3 MPa (an increase of 9.3%–16.6%), and the 28-day strength increases by 2.8–3.4 MPa (an increase of 5.9%–7.1%). Therefore, this invention is highly practical and significantly improves the fine grinding capacity and grinding efficiency of the ball mill.

[0111] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A material zone activation device for a ball mill, characterized in that, include: At least one activation module is disposed on the inner wall of the mill cylinder; The activation module rotates synchronously with the mill cylinder, and the activation module has at least one activation element extending into the dead material zone inside the mill. The activation element is used to forcibly agitate the material in the dead material zone inside the mill, construct a radial activation speed difference, and realize the radial activation of the material in the dead material zone. The dead material zone refers to the low-speed material zone located below the material surface inside the mill cylinder where the "material-ball" speed difference is the smallest. The activator is inclined in the circumferential direction of the mill against the material flow direction, and is used to generate a reverse thrust against the material flow direction when rotating, thereby prolonging the residence time of the material in the mill.

2. The material zone activation device for a ball mill according to claim 1, characterized in that, The activating element is a gradient activation blade, which is fixed to the first support ring plate and arranged between two first support ring plates. The first support ring plate is fixed to the support assembly, and the support assembly is fixed to the mill cylinder. The ratio of the length of a single gradient activation blade in the coarse grinding chamber to the effective length of the coarse grinding chamber is 0.11~0.41, and the ratio of the length of a single gradient activation blade in the fine grinding chamber to the effective length of the fine grinding chamber is 0.05~0.

16. The angle between the gradient activation blades and the mill radial direction The angle between the gradient activation blades and the mill axis is 25°~35°. The range is 20° to 40°.

3. The material zone activation device for a ball mill according to claim 2, characterized in that, The ratio of the inner diameter of the first support ring plate to the effective inner diameter of the mill cylinder is 0.65~0.85, and the ratio of the outer diameter of the first support ring plate to the effective inner diameter of the mill cylinder is 0.7~0.

9.

4. The material zone activation device for a ball mill according to claim 2, characterized in that, The gradient activation blades are either straight plates or spiral curved plates; when they are spiral curved plates, the end face profile of any point on the curved plate forms an angle with the radial direction of the mill. The angle between the contour normal of any point on the curved panel and the mill axis is 25°~35°. The range is 20° to 40°.

5. The material zone activation device for a ball mill according to claim 2, characterized in that, Both the coarse grinding chamber and the fine grinding chamber of the mill are equipped with gradient activation modules. The number of gradient activation modules in the coarse grinding chamber is... The number of gradient activation modules in the fine grinding chamber satisfy: In the formula, The effective length of the coarse grinding chamber. The effective length of the fine grinding chamber. =250~500mm, =150~250mm, =150~250mm, =150~250mm, =400~800mm, =400~800mm.

6. The material zone activation device of the ball mill according to claim 1, characterized in that, The activating element is a high-efficiency activating blade, which is installed on the second support ring plate and arranged between the two second support ring plates. The second support ring plate is fixed on the support assembly, and the support assembly is fixed on the mill cylinder. The ratio of the length of a single high-efficiency activating blade in the coarse grinding chamber to the effective length of the coarse grinding chamber is 0.22~0.85, and the ratio of the length of a single high-efficiency activating blade in the fine grinding chamber to the effective length of the fine grinding chamber is 0.1~0.

42. The angle between the highly activated blades and the radial direction of the mill. The angle between the blades and the mill axis is 25°~35°. The range is 20° to 40°.

7. The material zone activation device for a ball mill according to claim 6, characterized in that, The ratio of the inner diameter of the second support ring plate to the effective inner diameter of the mill cylinder is 0.65~0.85, and the ratio of the outer diameter of the second support ring plate to the effective inner diameter of the mill cylinder is 0.7~0.

9.

8. The material zone activation device for a ball mill according to claim 6, characterized in that, The highly effective activating blade is a straight plate or a spiral curved plate; when it is a spiral curved plate, the end face profile of any point on the curved plate has an angle with the radial direction of the mill. The angle between the contour normal of any point on the curved panel and the mill axis is 25°~35°. The range is 20° to 40°.

9. The material zone activation device for a ball mill according to claim 6, characterized in that, Both the coarse grinding chamber and the fine grinding chamber of the mill are equipped with high-efficiency activation modules. The number of high-efficiency activation modules in the coarse grinding chamber is... The number of high-efficiency activation modules in the fine grinding chamber satisfy: In the formula, The effective length of the coarse grinding chamber. The effective length of the fine grinding chamber. =250~500mm, =150~250mm, =150~250mm, =150~250mm, =250~500mm, =1500±500mm, =1500±500mm.

10. The material zone activation device for a ball mill according to claim 6, characterized in that, The two ends of the highly effective activating blade are fixedly installed on the second support ring plate.

11. The material zone activation device for a ball mill according to claim 6, characterized in that, One end of the high-efficiency activating blade is omnidirectionally mounted on the second support ring plate, and the other end is fixedly mounted on the second support ring plate, with the angle of this end on the second support ring plate along the circumference of the mill adjustable.

12. The material zone activation device for a ball mill according to claim 11, characterized in that, The end of the high-efficiency activation blade, which is fixedly installed on the second support ring plate, can be adjusted by 0~15° along the circumference of the mill on the second support ring plate.

13. The material zone activation device for a ball mill according to claim 11, characterized in that, One end of the high-efficiency activation blade is rotatably connected to the bearing seat via a blade support ball bearing, and the bearing seat is fastened to the second support ring plate. The other end of the high-efficiency activation blade is fastened to the second support ring plate via a blade positioning seat. The high-efficiency activation blade has at least one U-shaped groove for adjusting the position of the high-efficiency activation blade at the connection with the blade positioning seat. The second support ring plate has multiple adjustment holes for adjusting the installation position of the blade positioning seat at the connection with the blade positioning seat.

14. The material zone activation device for a ball mill according to claim 2 or 6, characterized in that, The support assembly includes a support liner plate, which is fixed to the mill cylinder, and a corresponding support ring plate is fixed to the support liner plate.

15. The material zone activation device for a ball mill according to claim 14, characterized in that, The support liner is divided into an inlay section and a support section. The inlay section is inlaid and fixed on the mill cylinder and is flush with the mill liner in the corresponding mill chamber. The support section extends toward the center of the mill.

16. The material zone activation device for a ball mill according to claim 15, characterized in that, The corresponding bracket ring plate is fixed on the support section.

17. The material zone activation device for a ball mill according to claim 14, characterized in that, The support liner is made of wear-resistant cast steel.

18. The material zone activation device for a ball mill according to claim 1, characterized in that, The activation element includes an activation ring, flow-controlling activation blades, and a flow-through orifice plate. The flow-through orifice plate has a porous structure for allowing some material to pass through. The flow-through orifice plate is disposed inside the activation ring, and its porosity is 15-35%. The flow-controlling activation blades are disposed on the activation ring, and the angle between the flow-controlling activation blades and the activation ring is [not specified]. The angle is 15° to 45°; the activation ring is fixed on the support assembly, and the support assembly is fixed on the mill cylinder.

19. The material zone activation device for a ball mill according to claim 1, characterized in that, The mill includes a mill cylinder, a mill inlet and a mill outlet located at opposite ends of the mill cylinder. Along the direction from the mill inlet to the mill outlet, the mill cylinder is divided into a coarse grinding chamber and a fine grinding chamber. A partition plate is installed between the coarse grinding chamber and the fine grinding chamber. Grinding chamber liners are installed on the inner walls of the coarse grinding chamber and the fine grinding chamber, respectively. A mill feed chute is installed at the mill inlet. A grinding grate is installed at the end of the mill cylinder near the mill outlet.

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