Energy-saving variable-frequency speed-regulating ball mill for realizing narrow-fraction ore grinding

Abstract

The utility model discloses an energy-saving variable-frequency speed regulation ball mill for realizing narrow-fraction ore grinding, and belongs to the technical field of ball mills. The output end of the cylinder body is provided with an ore discharge chute, the surface of the ore discharge chute is provided with a grading chute, the bottom of the grading chute is provided with a demagnetizing elbow, the output end of the demagnetizing elbow is provided with a fine-fraction electronic scale, and one side of the fine-fraction electronic scale is provided with a coarse-fraction electronic scale; and recovery chutes are arranged at the output ends of the coarse-fraction electronic scale and the fine-fraction electronic scale. According to the utility model, after the ore discharge chute and the grading chute are used for sampling at regular time and the demagnetizing elbow is used for eliminating residual magnetism of ore discharge products, coarse and fine fuzzy grading is completed on the electronic scale by utilizing the high flow rate of ore pulp and the inertia and sedimentation characteristics of minerals with different size fractions; and only the proportions of the coarse and fine fractions of the ore grinding products in different time periods are compared, so that the ore grinding effects in different time periods are judged, and other parameters are adjusted to stabilize production.

Description

TECHNICAL FIELD

[0001] The utility model relates to ball mill technical field more specifically, relate to a kind of energy-saving variable-frequency speed-regulating ball mill for realizing narrow particle size grinding. BACKGROUND

[0002] Ball mill is widely used for the dissociation equipment after mineral crushing. It realizes the impact, collision and grinding between grinding medium and mineral by the centrifugal force of rotation to drive the lifting and falling of grinding medium and mineral. When the speed of mill is too low, the impact force of grinding medium and material is not enough, and the fine grinding effect is poor. When the speed of mill is too high, the lifting height is too high, the impact force is too large, which causes overgrinding phenomenon or part of grinding medium and mineral does not have grinding process with the mill doing circular motion. In addition, in the production process of mining and selection, the fluctuation of raw ore properties is frequent. Under the fixed speed, overgrinding and difficult grinding phenomena often occur, which leads to the loss of concentrate in the selection system and the decrease of processing capacity. Furthermore, with the upgrading of industry, the cost reduction and the popularization of intelligent grinding, the grinding energy consumption index requirement is higher and higher, and the effect tracking and judgment of grinding also need to be accurate and timely.

[0003] At present, the feedback effect of grinding product particle size detection instrument on the market is not outstanding. How to accurately track the grinding effect with a simpler method and achieve narrow particle size grinding with lower energy consumption to reduce overgrinding and maintain high processing capacity is a difficult problem faced by current concentrators. UTILITY MODEL CONTENT

[0004] 1. Technical problem to be solved by the utility model

[0005] In view of the defects and deficiencies of the prior art, the utility model provides an energy-saving variable-frequency speed-regulating ball mill for realizing narrow particle size grinding. The utility model realizes time sampling through discharge chute and grading chute, eliminates the residual magnetism of discharge product through demagnetization elbow, and completes coarse and fine fuzzy grading on electronic scale by using the high flow rate of ore pulp itself and the inertia and sedimentation characteristics of different particle size minerals. The utility model adopts multiple sampling and large base number analysis, only compares the proportion of coarse and fine particle size of grinding product in different periods, so as to obtain the advantage and disadvantage judgment of grinding effect in different periods, and then adjusts other parameters to stabilize production.

[0006] 2. Technical scheme

[0007] To achieve the above purpose, the utility model provides the technical scheme as follows:

[0008] The utility model relates to a kind of energy-saving variable-frequency speed-regulating ball mill for realizing narrow particle size grinding, including cylinder, fixed gear is installed to the outer ring of cylinder, and fixed gear is engaged with driving gear;The inner ring of driving gear is provided with transmission shaft, and one end of transmission shaft penetrates driving gear and is connected with permanent magnet motor;

[0009] The inner wall of the barrel body is attached with a magnetic lining, and the inner cavity of the barrel body is filled with grinding medium; the input end of the barrel body is connected with a feeder, the output end of the barrel body is connected with a discharge device, and the output end of the discharge device is provided with a discharge box, and the bottom of the discharge device is provided with a discharge device.

[0010] The discharge device comprises a discharge chute and a grading chute; the surface of the discharge chute is provided with the grading chute, the connection part of the discharge chute and the grading chute is provided with a flap valve, the bottom of the grading chute is provided with a demagnetization elbow, the output end of the demagnetization elbow is provided with a fine particle level electronic scale, one side of the fine particle level electronic scale is provided with a coarse particle level electronic scale, the output ends of the coarse particle level electronic scale and the fine particle level electronic scale are provided with a recovery chute, and the output end of the recovery chute is connected with the discharge chute.

[0011] Further, the connection part of the feeder and the barrel body is provided with a sealing device.

[0012] Further, one end of the flap valve is provided with a hydraulic push rod, and the input end of the hydraulic push rod is provided with a hydraulic motor.

[0013] Further, the grinding medium is selected from ceramic balls with a ball diameter of 20mm-30mm and steel balls with a ball diameter of 30mm, the filling rate of the grinding medium is 40%-42%, and the ball mill grinds under the condition that the grinding concentration is 65%-68%.

[0014] Further, the slope of the grading chute is not less than 15°, a water supplement pipe is connected to the grading chute, an electric valve is arranged on the water supplement pipe, and the water supplement pipe supplements water regularly to reduce the discharge concentration and increase the discharge slurry flow rate.

[0015] Further, the coarse particle level electronic scale and the fine particle level electronic scale are both installed with a 3° slope, a flushing water pipe is arranged on the upper end of the coarse particle level electronic scale and the fine particle level electronic scale, and an electric valve is arranged on the surface of the flushing water pipe.

[0016] Further, the side edge of the barrel body is provided with a mill seat.

[0017] 3. Beneficial effects

[0018] Compared with the prior art, the technical scheme has the following beneficial effects:

[0019] The utility model discloses a mine discharge chute and grading chute timing sampling, after eliminating the residual magnetism of mine discharge product by demagnetization elbow, utilize the high flow rate of ore pulp and the inertia and the settlement characteristic of different size minerals, complete the coarse and fine fuzzy classification on the electronic scale, abandon the concept of pursuing accurate particle size distribution, directly discard the sampling, high price, high failure rate and difficult maintenance problem of precision instrument of detecting granularity, adopt the big base number analysis of multiple sampling, only compare the coarse and fine size of grinding product in different time, thereby obtain the grinding effect advantage and disadvantage judgment in different time, and then adjust other parameters and stabilize production.

[0020] The utility model discloses a mixed use of ceramic ball and steel ball, reduce the average density and ball diameter of grinding medium, reduce the grinding power consumption and ball consumption of ball mill, improve the filling rate and strengthen the grinding effect, realize the speed change of ball mill with the variable frequency permanent magnet motor of simpler structure and higher driving efficiency, adjust the speed of ball mill according to the analysis of mine discharge granularity, adjust other parameters in time, improve the overgrinding phenomenon, realize the narrow size grinding, and the grinding energy consumption is reduced obviously. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 It is the front view of the utility model;

[0022] Figure 2 It is the partial plan view of the utility model.

[0023] In the drawing: 1, permanent magnet motor;2, mill base body;3, transmission shaft;4, driving gear;5, nested device;6, slow drive motor;7, cylinder;8, feeder;9, sealing device;10, grinding medium;11, magnetic lining;12, fixed gear;13, mine discharger;14, mine discharge box;15, mine discharge chute;16, hydraulic motor;17, hydraulic push rod;18, flap valve;19, grading chute;20, electric valve;21, water supply pipe;22, demagnetization elbow;23, coarse size electronic scale;24, fine size electronic scale;25, recovery chute;26, flushing water pipe;27, slow drive shaft. DETAILED DESCRIPTION

[0024] The utility model will be further described in connection with the drawings and examples:

[0025] Example 1

[0026] From Figures 1-2 It can be seen that the energy-saving variable frequency speed regulation ball mill for realizing narrow size grinding of the embodiment includes the cylinder 7, the outer ring of the cylinder 7 is installed with the fixed gear 12, the fixed gear 12 is engaged with the driving gear 4;The inner ring of the driving gear 4 is provided with the transmission shaft 3, one end of the transmission shaft 3 penetrates the driving gear 4 and is connected with the permanent magnet motor 1;The permanent magnet motor 1 drives the driving gear 4, the fixed gear 12 and the cylinder 7 to rotate through the transmission shaft 3;

[0027] The inner wall of the barrel 7 is attached with a magnetic lining 11, and the inner cavity of the barrel 7 is filled with grinding medium 10; the grinding medium 10 is selected from ceramic balls with a ball diameter of 20mm-30mm and steel balls with a ball diameter of 30mm, the filling rate of the grinding medium 10 is 40%-42%, and the ball mill grinds under the condition of a grinding concentration of 65%-68%;

[0028] When grinding, a layer of steel balls and ore powder is adsorbed on the inner surface of the barrel 7, which is used to reduce the impact between the grinding medium 10 and the magnetic lining 11, protect the magnetic lining 11, and reduce noise;

[0029] The input end of the barrel 7 is connected with a feeder 8, and a sealing device 9 is arranged at the connection between the feeder 8 and the barrel 7 to avoid the phenomenon of the feeder 8 being reversed due to the high liquid level in the barrel 7 caused by the high filling rate of the grinding medium 10; the output end of the barrel 7 is connected with a discharge device 13, and the output end of the discharge device 13 is provided with a discharge box 14 for collecting large-particle hard stones and abnormally discharged grinding medium 10, facilitating safe cleaning during production of the ball mill; the bottom of the discharge device 13 is provided with a discharge device; the undersize product of the discharge device 13 enters a discharge chute 15;

[0030] The discharge device includes the discharge chute 15 and a classification chute 19; the surface of the discharge chute 15 is provided with the classification chute 19, and the connection between the discharge chute 15 and the classification chute 19 is provided with a flap valve 18; one end of the flap valve 18 is provided with a hydraulic push rod 17, and the input end of the hydraulic push rod 17 is provided with a hydraulic motor 16;

[0031] The bottom of the classification chute 19 is provided with a demagnetization elbow 22, the output end of the demagnetization elbow 22 is provided with a fine particle level electronic scale 24, one side of the fine particle level electronic scale 24 is provided with a coarse particle level electronic scale 23, the output ends of the coarse particle level electronic scale 23 and the fine particle level electronic scale 24 are provided with a recovery chute 25, and the output end of the recovery chute 25 is connected with the discharge chute 15; all the slurry is finally collected in the discharge chute 15.

[0032] The slope of the classification chute 19 is not less than 15°, a water supply pipe 21 is connected to the classification chute 19, an electric valve 20 is arranged on the water supply pipe 21, and the water supply pipe 21 supplies water at regular intervals to reduce the discharge concentration and increase the flow rate of the discharge slurry.

[0033] The electric valve 20 of the water supply pipe 21 is opened before the discharge product enters the classification chute 19, the concentration of the discharge product is reduced, the flow rate of the slurry is increased, and the slurry is in a turbulent state;

[0034] Both the coarse-grained electronic scale 23 and the fine-grained electronic scale 24 are installed with a 3° slope to allow the minerals on the surface of the scale to drain naturally. The upper end of the coarse-grained electronic scale 23 and the fine-grained electronic scale 24 is provided with a rinsing water pipe 26, and an electric valve 20 is provided on the surface of the rinsing water pipe 26 for rinsing the minerals on the surface of the electronic scale.

[0035] The coarse-grained electronic scale 23 and the fine-grained electronic scale 24 are combined with the flap valve 18 to collect the discharged ore products for classification and weighing, and to analyze the grinding effect.

[0036] Ball mills can also be equipped with automatic valve switching systems, electronic scale signal collection and analysis systems, and power current monitoring systems. By comparing the weighing of coarse and fine particles over a period of time, the grinding effect and energy consumption can be analyzed, the frequency of the permanent magnet motor can be adjusted, and the mill speed can be changed.

[0037] This invention aims to address the problems of over-grinding, high grinding energy consumption, insufficient detection accuracy, and difficult maintenance of detection instruments by providing a simple device for tracking grinding effects, combined with lighter grinding media and an adjustable speed mill, to achieve narrow-particle-size energy-saving grinding.

[0038] This invention uses timed sampling in discharge sluices and classification sluices. After the residual magnetism of the discharged products is eliminated by demagnetizing elbows, the high flow rate of the slurry and the inertia and settling characteristics of minerals of different particle sizes are utilized to complete fuzzy classification of coarse and fine particles on an electronic scale. It abandons the concept of pursuing precise particle size distribution and directly discards the problems of difficult sampling, high price, high failure rate and difficult maintenance of precision instruments for particle size detection. It adopts large-scale analysis with multiple sampling and only compares the proportion of coarse and fine particle sizes of the grinding products at different time periods, thereby obtaining a judgment on the quality of grinding effect at different time periods, and then adjusting other parameters to stabilize production.

[0039] This invention reduces the average density and diameter of the grinding media by using a mixture of ceramic and steel balls, thereby reducing the grinding power consumption and ball consumption of the ball mill, increasing the filling rate, and enhancing the grinding effect. Combined with a simpler and more efficient variable frequency permanent magnet motor, it achieves mill speed regulation. Based on the analysis of the discharged particle size, the mill speed is appropriately adjusted, and other parameters are adjusted in a timely manner to improve over-grinding, achieving narrow-particle grinding and reducing grinding energy consumption by up to 10%.

[0040] Example 2

[0041] from Figure 1 As can be seen, in this embodiment of an energy-saving variable frequency speed-regulating ball mill for narrow-particle grinding, a mill base 2 is provided on the side of the cylinder 7 to support the various components of the mill.

[0042] One side of the driving gear 4 is provided with a slow drive motor 6, the output end of the slow drive motor 6 is provided with a slow drive shaft 27, the shaft of the slow drive shaft 27 is provided with a nesting device 5, during the daily maintenance process of the ball mill, the permanent magnet motor 1 stops driving, the slow drive motor 6 drives the driving gear 4 to rotate at low speed through the slow drive shaft 27 and the nesting device 5.

[0043] Embodiment 3

[0044] From Figure 2 It can be seen that the energy-saving variable frequency speed regulation ball mill for narrow particle size grinding in the embodiment can complete the coarse and fine fuzzy classification on the coarse particle level electronic scale 23 and the fine particle level electronic scale 24 by using the high flow rate of the ore pulp itself and the inertia and settling characteristics of different particle size minerals after the ore pulp flows out from the demagnetization elbow 22 and has an initial speed. Therefore, the motion trajectories of different particle size minerals will have different arcs, and the grinding effect of different time periods can be judged by comparing the proportions of coarse and fine particle levels of the grinding products in different time periods through multiple sampling and large base number analysis.

[0045] Embodiment 4

[0046] From Figures 1-2 It can be seen that the energy-saving variable frequency speed regulation ball mill for narrow particle size grinding in the embodiment, in the industrial test of a certain iron separation plant, for the two series of two-stage grinding classification system using closed-circuit grinding classification, one series uses a Φ3660 mill with manganese steel lining, and the other series uses a Φ4060 mill with magnetic lining; the effective volume of the two mills is 55m 3 ; the ratio of the diameters of the nanoceramic balls is Φ30mm:Φ25mm:Φ20mm=20%:60%:20%, the filling rate is 35%, the diameter of the steel ball is Φ30mm, the filling rate is 6%, the grinding concentration is 65%-68%, and the grinding is performed by using the mill; the two series are driven by the same power variable frequency permanent magnet motor, and the same ore source, the same treatment capacity and the same classification system are used. The classification chute opens and closes the flap valve and the water supplement electric valve once every 15 minutes, and the electronic scale collects data every 30s and records the proportions of coarse and fine particle levels.

[0047] For the soft magnetite ore, the rotating speeds of the mill in the first series and the second series are controlled to be 19r / min and 18r / min respectively.

[0048] The product particle size distribution of the first series grinding classification system is shown in Table 1, and the product particle size distribution of the second series grinding classification system is shown in Table 2. The return sand ratio, the new ball mill production rate, the overground particle level yield and the mill current of the first series and the second series are shown in Table 3.

[0049] Table 1-Product particle size distribution of the first series grinding (yield / %)

[0050] Particle size / mm 1# row of ore Feeding (sand) Overflow +0.3 3.58 7.18 0 -0.3～+0.15 14.02 18.89 1.57 -0.15～+0.1 20.09 21.27 7.22 -0.1～+0.076 17.52 17.83 5.75 -0.076～+0.045 24.28 24.77 18.20 -0.045～+0.03 6.77 4.44 13.39 -0.030 13.74 5.62 53.87 Total 100.00 100.00 100.00 -0.076 44.79 34.83 85.46

[0051] Table 2-2 series grinding product size distribution (yield / %)

[0052]

[0053]

[0054] Table 3 - sand return ratio, ball mill new production and mill current

[0055]

[0056] The above data shows that, compared with traditional mill grinding, the overall grinding product of the present application has relatively higher new production rate of -0.076 mm size fraction, the +0.15 mm size fraction of the 2 series of the discharge product is relatively 6.96% higher, the -0.045 mm size fraction yield is relatively lower, especially the -0.03 mm size fraction yield is lower, which shows that the overgrinding phenomenon is improved; the sand return ratio of the grinding classification system is similar, the mill current is lower, and the grinding power consumption is reduced by 11.59%.

[0057] The above has described the present application and its embodiments in a schematic manner, which is not restrictive, and the embodiments shown in the drawings are only one of the embodiments of the present application, and the actual structure is not limited thereto. Therefore, if a person of ordinary skill in the art is inspired by it, without departing from the creative purpose of the present application, similar structural modes and embodiments can be designed without creativity, which should all belong to the protection scope of the present application.

Claims

1. An energy saving variable frequency speed regulated ball mill for achieving narrow size fraction grinding comprising a cylindrical shell (7) characterised in that: The outer ring of the barrel (7) is provided with a fixed gear (12), and the fixed gear (12) is engaged with the driving gear (4); the inner ring of the driving gear (4) is provided with a transmission shaft (3), one end of the transmission shaft (3) penetrates through the driving gear (4) and is connected with a permanent magnet motor (1); The inner wall of the barrel (7) is attached with a magnetic lining plate (11), and the inner cavity of the barrel (7) is filled with grinding medium (10); the input end of the barrel (7) is connected with a feeder (8), and the output end of the barrel (7) is connected with a discharge device (13), and the output end of the discharge device (13) is provided with a discharge box (14), and the bottom of the discharge device (13) is provided with a discharge device; The discharge device comprises a discharge chute (15) and a grading chute (19); the surface of the discharge chute (15) is provided with the grading chute (19), the connection part of the discharge chute (15) and the grading chute (19) is provided with a flap valve (18), the bottom of the grading chute (19) is provided with a demagnetization elbow (22), the output end of the demagnetization elbow (22) is provided with a fine particle level electronic scale (24), one side of the fine particle level electronic scale (24) is provided with a coarse particle level electronic scale (23), and the output ends of the coarse particle level electronic scale (23) and the fine particle level electronic scale (24) are provided with a recovery chute (25), and the output end of the recovery chute (25) is connected with the discharge chute (15).

2. The energy-saving variable frequency speed-adjusting ball mill for realizing narrow size fraction grinding according to claim 1, characterized in that: The connection part of the feeder (8) and the barrel (7) is provided with a sealing device (9).

3. The energy saving variable frequency speed regulated ball mill for achieving narrow size fraction grinding as claimed in claim 2 wherein: One end of the flap valve (18) is provided with a hydraulic push rod (17), and the input end of the hydraulic push rod (17) is provided with a hydraulic motor (16).

4. The energy-saving variable frequency speed-adjustable ball mill for achieving narrow size fraction grinding according to claim 3, characterized in that: The grinding medium (10) is selected from ceramic balls with a ball diameter of 20mm-30mm and steel balls with a ball diameter of 30mm, the filling rate of the grinding medium (10) is 40%-42%, and the ball mill grinds the ore under the condition that the ore concentration is 65%-68%.

5. The energy saving variable frequency ball mill for achieving narrow size fraction grinding as claimed in claim 4 wherein: The slope of the grading chute (19) is not less than 15°, a water supplement pipe (21) is connected to the grading chute (19), an electric valve (20) is arranged on the water supplement pipe (21), and the water supplement pipe (21) is used for supplementing water at regular time to reduce the discharge concentration and increase the discharge slurry flow rate.

6. The energy saving variable frequency ball mill for achieving narrow size fraction grinding as claimed in claim 5 wherein: The coarse particle level electronic scale (23) and the fine particle level electronic scale (24) are both installed with a 3° slope, and the upper end of the coarse particle level electronic scale (23) and the fine particle level electronic scale (24) is provided with a flushing water pipe (26), and the surface of the flushing water pipe (26) is provided with an electric valve (20).

7. The energy saving variable frequency ball mill for achieving narrow size fraction grinding as claimed in claim 1 wherein: The side of the barrel (7) is provided with a mill seat (2).

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