Combined grinding system with pre-grinding equipment
Technical Field
The invention relates to the technical field of grinding, in particular to a combined grinding system with pre-grinding equipment.
Background
The ball mill comprises a cylinder and a grinding body, when the ball mill cylinder rotates, the grinding body is attached to a cylinder lining plate and taken away by the cylinder due to the action of inertia, centrifugal force and friction force, when the ball mill cylinder is taken to a certain height, the ball mill is thrown down due to the gravity action of the ball mill cylinder, and the thrown-down grinding body crushes materials under the action of gravity and impact force to realize material grinding. Because the ball mill has simple structure and good equipment reliability, the ball mill is widely used in the industries of building materials, mineral separation, metallurgy, electric power, medicine, food, chemical engineering and the like. The ball mill can be divided into a dry type and a wet type according to different grinding environments; according to different transmission modes, the transmission mode can be divided into a center transmission mode and an edge transmission mode.
Although the ball mill has simple structure, the grinding principle of the ball mill is that the ball mill is singleThe particle impact crushing has low grinding efficiency, and a large amount of energy is converted into potential energy for lifting the steel balls and the materials, kinetic energy for impact between the steel balls and grinding heating when the materials are crushed. Research data show that the energy utilization rate of the ball mill is less than 5%. Because the thick and thin materials in the ball mill are mixed, the fine powder meeting the product requirement is easy to agglomerate in the mill, the agglomerated materials are bonded on the lining plate to form a cushion layer, and researches show that when the cushion layer of the lining plate is 0.2mm, the impact force of the steel ball is reduced by 80%. The external embodiment is that the ball mill has the problems of ball pasting, full grinding and the like, so that the ball mill cannot be normally produced, or the production energy consumption is very high during the production of the ball mill. Zhou good (cement technology, 6 th year 2014) introduced a technology of grinding ultrafine cement grouting material by using a phi 2.6 x 13m ball mill, and when the ultrafine cement is completely produced by using P.O 52.5 cement, the ball is seriously pasted by the mill; when the clinker and the gypsum are all used for grinding the superfine cement, the yield is too low, and the power consumption is too high. The scheme adopted finally is as follows: 70 percent of P.O 52.5 is adopted, and 30 percent of clinker and gypsum are added, so that the continuous normal production of a mill can be ensured; after being ground, 8 percent of silica fume (the specific surface area is 2000 m) is added 2 /kg) of the raw materials are put into a powder concentrator together to realize that the specific surface area of the product is more than or equal to 800m 2 And the power consumption of the working procedure is up to 155kW/t.
Therefore, in order to improve the yield of the ball mill system and reduce the grinding energy consumption, a powder concentrator technology gradually appears. The method comprises the following steps: and (3) sending the material ground by the ball mill into a powder selecting machine through a lifter, so that qualified materials are selected in time in the powder selecting machine, and unqualified materials return to the ball mill for continuous grinding. Due to the appearance and maturity of the technology of the powder concentrator, the power consumption of a grinding system of the ball mill is greatly reduced, but materials need to be lifted to the top of the powder concentrator due to the limitation of process arrangement, so that the equipment is increased, the civil engineering cost is increased, and the investment cost is high.
Chinese patent publication No. CN201197950 discloses an internal selection powder screening composite cement mill, which comprises a cylinder and an internal screening device, wherein the internal screening device comprises a grate plate, a coarse powder guide cone, a tubular screen, a fine powder guide cone and an annular pipe. One end of the tubular sieve is arranged on the circumferential surface of the annular pipe and is communicated with the annular pipe, the other end of the tubular sieve is arranged on the inner wall of the cylinder body, and the annular pipe is provided with a coarse powder guide cone and a fine powder guide cone at the end, and the tubular sieve further comprises a sieve plate, a ventilation grate plate and a material blocking inclined plate. The ventilation grate plate is arranged at the other end of the annular pipe, the sieve plate is arranged between the tubular sieve and the ventilation grate plate, one side surface of the tubular sieve is arranged on the sieve plate, and the material blocking inclined plate is arranged on the edge of the outer end of the sieve surface of the tubular sieve. The essence of the method is that the functions of the partition board are supplemented, and a grate board is arranged in front of the original partition board, but the method has no substantial internal selection and screening functions.
Chinese patent publication No. CN101920219A discloses a powder selecting device in a dry ball mill, which is characterized in that a stainless steel powder selecting pipe is arranged in an inner cavity of the dry ball mill, and is connected with a powder selecting connecting pipe one and a powder selecting connecting pipe two of a mill tail separation bin in parallel, a finished product conveying pipe, a catcher (cyclone and bag type dust remover group), a fan, a stainless steel material returning pipe, and a ball mill sequential gas and material closed loop connection. The powder selecting pipe timely selects finished materials formed by grinding the mill interior and mill tail in a negative pressure state by utilizing the suction force of the fan. The core of the method is that a steel pipe is arranged in a grinding bin of the ball mill, and a finished product is selected out through the steel pipe under the action of negative pressure. The stainless steel powder selecting pipe is arranged in the grinding bin, and the steel ball is thrown down to easily deform the steel pipe, so that the stainless steel powder selecting pipe has no practicability; in addition, the powder is drawn out of the steel pipe by the negative pressure, and the powder sorting function is not provided.
In addition, when the pre-sorted medium and coarse materials are continuously ground by adopting a ball mill, if the ball mill adopts an open-flow process, the existing combined grinding system can cause the over-grinding phenomenon of the materials in the ball mill, the production power consumption is high, and the product quality control convenience is poor; if the circulation process is adopted, the powder concentrator needs to be arranged on a platform above the height of a ball mill plant, materials discharged from the ball mill need to be fed into the powder concentrator through a chute, a lifter and the like, the height of the whole workshop is 2 times larger than the height of the ball mill plant, the investment cost is high, a plurality of auxiliary equipment are provided, the production energy consumption is high, and the maintenance is difficult.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a combined grinding system with pre-grinding equipment, which can continuously grind and sort pre-sorted medium and coarse materials and discharge qualified fine powder generated in the grinding process in time, thereby reducing the phenomenon of fine powder agglomeration or over-grinding in a ball mill, improving the wind efficiency of the system, reducing the wind energy consumption of the system, reducing the workshop height, reducing the investment cost of a grinding system, reducing the grinding energy consumption of the ball mill, improving the grinding efficiency, increasing the energy utilization rate, and promoting energy conservation and emission reduction.
The invention is realized in such a way, a combined grinding system with pre-grinding equipment comprises roller mill equipment, a combined type powder concentrator, a first dust collector, a self-sorting type ball mill, a second dust collector and a fan, wherein a discharge hole of the roller mill equipment is connected with a feed inlet of the combined type powder concentrator through a hoisting machine, a discharge hole at the bottom of the combined type powder concentrator is connected with a feed inlet of the roller mill equipment, a discharge hole at the upper part of the combined type powder concentrator is connected with a first dust collector inlet, a first dust collector outlet is connected with the fan, a middle discharge hole of the combined type powder concentrator is connected with a self-sorting type ball mill feed inlet, a discharge hole of the self-sorting type ball mill is connected with a second dust collector inlet, and a second dust collector outlet is connected with the fan;
the self-sorting ball mill comprises a cylinder body, a feeding hole and a discharging hole, wherein the cylinder body inclines upwards from the side of the feeding hole to the side of the discharging hole, and the inclination angle is 2-5 degrees; a grinding bin and a powder selecting bin are sequentially arranged in the barrel from a feeding hole to a discharging hole, and a main partition board is arranged between the grinding bin and the powder selecting bin; and a static powder concentrator and/or a dynamic powder concentrator are arranged in the powder concentration bin.
Preferably, an inclined lining plate is arranged on the inner wall of the barrel of the powder selecting bin, and the included angle between the inclined lining plate and the axis of the barrel is 3-15 degrees.
Preferably, the dynamic powder concentrator is composed of a rotor, a reaction cone, a transmission shaft and a powder concentrator drive, wherein blades of the rotor are parallel to an inclined lining plate in a powder concentrator, the reaction cone is fixed at the bottom of the rotor, and the diameter of the reaction cone is the same as the outer diameter of the rotor; the rotor is connected with the powder concentrator through a transmission shaft for driving.
Preferably, when only the dynamic powder concentrator is arranged in the powder separation bin, the main bin partition plate is provided with vent holes positioned in a central area and grate seams positioned at the periphery, the center of each vent hole is coaxial with the mill barrel, the diameter of each vent hole is 0.2-0.4 times of that of the mill barrel, each vent hole is of a net structure, and the effective size of each mesh hole is 10-15 mm; the grate seam close to the periphery of the vent hole is a conical grate seam, the diameter of the grate seam is gradually increased from the grinding bin side to the powder selecting bin side, the diameter of the grate seam close to the grinding bin side is 4-10 mm, and the diameter of the grate seam close to the powder selecting bin side is 6-12 mm; the grate seam close to the edge area of the main partition plate is a strip-shaped grate seam, and the length of the grate seam is 25mm and the width of the grate seam is 4mm; the thickness of the main compartment plate is 20-60 mm.
Preferably, when the powder selecting bin is internally provided with the static powder selecting machine and the dynamic powder selecting machine, the static blades of the static powder selecting machine are arranged in a conical shape, and the static powder selecting machine is positioned between the main bin separating plate and the dynamic powder selecting machine.
Preferably, the static powder concentrator comprises static blades which are arranged in a conical manner or are arranged in parallel with the axis of the cylinder;
when the static blades are arranged in a conical shape, the included angle between the static blades and the axis of the barrel is 45-65 degrees, the diameter of the section of the cone of the static blades is gradually increased from the grinding bin side to the powder selecting bin side, one end, close to the grinding bin, of each static blade is fixed on the main partition board, and the other end of each static blade is fixed on the barrel; at the moment, the inner area of the intersection of the main partition plate and the conical static blades is a blind plate, and the outer area is provided with a grid seam; the width of each static blade is 50-300 mm, and the gap between two adjacent static blades is 50-400 mm;
when the static blades are arranged in parallel with the axis of the cylinder body, one end of each static blade close to the grinding bin is fixed on the main bin partition plate, and the other end of each static blade is fixed on the cylinder body; at the moment, the inner area of the intersection of the main partition plate and the static blades is a blind plate, and the outer area is provided with a grid joint; the width of each static blade is 50-300 mm, and the gap between two adjacent static blades is 100-400 mm.
Preferably, the grinding lining plate is arranged on the inner wall of the barrel body of the grinding bin, and a plurality of activation rings are arranged in the grinding bin.
Preferably, the included angle between the feed inlet and the axis of the cylinder body is greater than 45 degrees, and an external fixing structure is adopted and does not rotate along with the cylinder body.
Preferably, the discharge end of the feed inlet is provided with a material preventing device, the material preventing device is composed of a conical telescopic steel sheet, a light spring and a lifting plate, the conical telescopic steel sheet is positioned on the inner side of the lifting plate, the large-diameter end of the conical telescopic steel sheet is fixed on the lifting plate, and the small-diameter end of the conical telescopic steel sheet is connected with the lifting plate through the light springs; the conical telescopic steel sheet is formed by sequentially stacking and enclosing a plurality of baffle plates, and each baffle plate corresponds to one light spring; the length of the material raising plate is larger than that of the conical telescopic steel sheet.
The invention has the following advantages and beneficial effects:
1) The grinding system can collect pre-sorted fine materials and continuously grind and sort medium and coarse materials, and can discharge qualified fine powder generated in the grinding process in time, thereby reducing excessive grinding of the materials in the ball mill, saving power consumption of grinding, and being beneficial to energy conservation and emission reduction of production enterprises.
2) The grinding system can shorten the finished product quality adjusting time, adjust the material quantity and the finished product quantity in the ball mill in real time, efficiently control the yield, improve the production efficiency and reduce the production cost.
3) According to the self-sorting ball mill, the grinding and sorting of materials are completed in the ball mill, an external powder concentrator is not needed, the height and the floor area of a factory building can be effectively reduced, auxiliary equipment such as a hoister and a conveying chute can be reduced, the investment cost is saved, the equipment failure rate is reduced, and the production and maintenance cost is reduced.
4) The self-sorting ball mill provided by the invention can integrate grinding and sorting, reduce the process flow, improve the wind efficiency of the system, reduce the wind amount by 50-70% compared with the traditional circulation system, and reduce the wind energy consumption of the system.
5) According to the self-sorting ball mill, the powder selecting machine and the ball mill are on the same horizontal plane, and the height of the powder selecting machine of the traditional circulation system is 2-3 times of the height of the ball mill, so that compared with the traditional circulation (the ball mill and the powder selecting machine) system, the self-sorting ball mill disclosed by the invention has the advantages that the height of the material to be lifted is reduced, the potential energy to be overcome is reduced, and the production energy consumption of the system is saved.
6) The self-sorting ball mill provided by the invention has the advantages that auxiliary equipment such as a lifting machine, a conveying chute and the like are omitted, pollution points of leakage and leakage in a system are reduced, the disordered discharge amount of dust is reduced, and the clean production and the environmental protection are facilitated.
Drawings
Fig. 1 is a flow chart of an integrated grinding system with pre-grinding equipment according to an embodiment of the present invention;
FIG. 2 is a schematic structural diagram of a self-sorting ball mill according to an embodiment of the present invention;
FIG. 3 is a front view of a main compartment plate according to an embodiment of the present invention;
FIG. 4 is a sectional view of a main partition panel according to an embodiment of the present invention;
fig. 5 is a schematic structural diagram of an anti-loader according to an embodiment of the present invention;
FIG. 6 is a schematic structural diagram of an activation ring provided in accordance with one embodiment of the present invention;
FIG. 7 is a schematic structural diagram of a self-classifying ball mill provided in the second embodiment of the present invention;
FIG. 8 is a front view of a main bulkhead according to a second embodiment of the present invention;
FIG. 9 is a sectional view of a main partition panel according to a second embodiment of the present invention;
FIG. 10 is a schematic structural diagram of a self-sorting ball mill provided in the third embodiment of the present invention;
FIG. 11 is a front view of a second main compartment plate according to a third embodiment of the present invention;
fig. 12 is a sectional view of a main partition panel ii according to a third embodiment of the present invention.
In the figure: 1. a first hoist; 2. a buffer bin; 3. a roller mill device; 4. a second hoist; 5. a combined powder concentrator; 6. a first dust collector; 7. a self-sorting ball mill; 8. a first fan; 9. a second dust collector; 11. a second fan;
10. a barrel; 101. a feed inlet; 102. a discharge port; 103. a dust collection port;
20. a grinding bin; 201. grinding the lining plate; 202. an activation ring;
30. selecting powder; 301. an inclined lining plate; 310. a dynamic powder concentrator; 311. a rotor; 312. a counterattack cone; 313. a drive shaft; 314. driving the powder concentrator; 320. static powder selecting machine; 321. a static blade;
40. a main partition panel; 401. a vent hole; 402. performing grate joint;
50. a material anti-scour device; 501. a tapered retractable steel sheet; 5011. a baffle plate; 502. a light-weight spring; 503. a material raising plate.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the invention.
In the description of the present invention, it should be noted that the terms "upper", "lower", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
In the description of the present invention, it should be noted that, unless explicitly stated or limited otherwise, the terms "connected" and "connected" are to be interpreted broadly, e.g., as being fixed or detachable or integrally connected; may be a mechanical connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Example 1
Referring to fig. 1, the present embodiment provides an integrated grinding system with pre-grinding equipment, which includes a roller mill 3 (a roller press or an external circulation vertical mill), a combined type powder concentrator 5, a first dust collector 6, a first fan 8, a self-sorting type ball mill 7, a second dust collector 9, and a second fan 11. The discharge hole of the roller mill equipment 3 (a roller press or an external circulation vertical mill) is connected with the feed hole of the combined type powder concentrator 5 through a second elevator 4, the bottom discharge hole of the combined type powder concentrator 5 is connected with the feed hole of the roller mill equipment 3, the upper discharge hole of the combined type powder concentrator 5 is connected with a first dust collector 6 inlet, a first dust collector 6 air outlet is connected with a first fan 8, the middle discharge hole of the combined type powder concentrator 5 is connected with a self-sorting type ball mill 7 feed hole 101, a self-sorting type ball mill 7 discharge hole 102 is connected with a second dust collector 9 inlet, and a second dust collector 9 air outlet is connected with a second fan 11.
Raw materials enter a buffer bin 2 through a first lifting machine 1, then enter a roller mill 3, are crushed through the roller mill 3, enter a combined type powder concentrator 5 through a second lifting machine 4, and fine materials separated through the combined type powder concentrator 5 enter a first dust collector 6 to be collected as finished products; conveying the intermediate material to a self-sorting type ball mill 7, further grinding and sorting, and feeding a sorted finished product into a second dust collector 9 to be collected as a finished product; the coarse materials return to the roller mill 3 to be crushed again and enter the next combined grinding. And mixing and storing the materials obtained by the first dust collector 6 and the second dust collector 9 as products, discharging the waste gas discharged from the first dust collector 6 and the second dust collector 9 into a chimney through respective corresponding fans, and finally discharging the waste gas into the atmosphere.
Referring to fig. 2 to 6, the self-sorting ball mill includes a cylinder 10, a feed inlet 101, and a discharge outlet 102, wherein the cylinder 10 is inclined upward from the feed inlet 101 side to the discharge outlet 102 side at an angle of 2 to 5 °; the barrel 10 is driven to rotate by a mill drive (the mill drive is not shown in the figure, and the barrel 10 can be driven to rotate by a gear transmission or other modes), and a grinding bin 20 and a powder selecting bin 30 are arranged in the barrel 10 from a feeding hole 101 to a discharging hole 102 in sequence.
The inner wall of the cylinder body 10 of the grinding bin 20 is provided with a grinding lining plate 201, and the grinding lining plate 201 is parallel to the axis of the cylinder body 10; the activation rings 202 are arranged in the grinding bin 20, so that the material retention time can be increased, the material grinding time can be prolonged, the specific structures of the activation rings 202 can be selected according to needs, and only one of the activation rings is illustrated in the embodiment. The grinding bin 20 is 1 bin or a plurality of bins, and when a plurality of bins are adopted, a bin separating plate is arranged between the bins.
An inclined lining plate 301 is arranged on the inner wall of the barrel 10 of the powder selecting bin 30, the inner diameter of the inclined lining plate 301 is gradually reduced from the feeding end of the powder selecting bin 30 to the discharging end of the powder selecting bin 30, and the included angle between the inclined lining plate 301 and the axis of the barrel 10 is 3-15 degrees. The powder selecting bin 30 is internally provided with a dynamic powder selecting machine 310, the dynamic powder selecting machine 310 consists of a rotor 311, a reaction cone 312, a transmission shaft 313 and a powder selecting machine drive 314, blades of the rotor 311 are parallel to the inclined lining plate 301, the reaction cone 312 is fixed at the bottom of the rotor 311, the diameter of the reaction cone 312 is the same as the outer diameter of the rotor 311, and the reaction cone 312 is used for controlling the speed of a material entering the dynamic powder selecting machine 310 and reducing the impact of the material on the blades of the dynamic powder selecting machine 310; secondly, if the bottom adopts the blind plate structure, the materials and the gas impact on the dynamic powder concentrator 310 at 90 degrees, and the gas has no guiding function when entering the blades of the dynamic powder concentrator 310, so that the general wind resistance is large. The rotor 311 is connected with a powder concentrator drive 314 outside the powder concentrator 30 through a transmission shaft 313, specifically, the powder concentrator drive 314 comprises a speed reducer and a motor, and the transmission shaft 313 is connected with the motor through the speed reducer.
A main partition board 40 is arranged between the grinding bin 20 and the powder selecting bin 30, and the thickness of the main partition board 40 is 20-60 mm. The main partition board 40 is provided with vent holes 401 positioned in the central area and grate seams 402 positioned at the periphery, the center of the vent holes 401 is coaxial with the mill cylinder 10, the diameter of the vent holes 401 is 0.2-0.4 times of the diameter of the mill cylinder 10, the vent holes 401 are of a net structure, and the effective size of the net holes is 10-15 mm; the grate gaps 402 near the periphery of the vent holes 401 are conical grate gaps, the diameters of the grate gaps 402 are gradually increased from the grinding bin 20 side to the powder selecting bin 30 side, the diameter of the grate gap 402 near the grinding bin 20 side is 4-10 mm, and the diameter of the grate gap 402 near the powder selecting bin 30 side is 6-12 mm; the slits 402 near the edge of the main partition 40 are elongated and have a dimension of 25mm in length and 4mm in width.
The included angle between the feed inlet 101 and the axis of the cylinder 10 is larger than 45 degrees, and the feed inlet does not rotate along with the cylinder 10 due to the adoption of an external fixing structure.
The material-preventing device 50 is arranged at the discharge end of the feed inlet 101, the material-preventing device 50 is mounted on a cylinder 10 of the ball mill and consists of a conical telescopic steel sheet 501, a light spring 502 and a lifting plate 503, the conical telescopic steel sheet 501 is positioned at the inner side of the lifting plate 503, the large-diameter end of the conical telescopic steel sheet 501 is fixed on the lifting plate 503, and the small-diameter end is connected with the lifting plate 503 through the light springs 502; the conical telescopic steel sheet 501 is formed by sequentially stacking a plurality of baffle pieces 5011, and each baffle piece 5011 corresponds to one light spring 502; the cross sections of the conical telescopic steel sheet 501 and the material raising plate 503 are circular. The length of the material raising plate 503 is 1.2-1.5 times of the horizontal length of the conical telescopic steel sheet 501. When the material amount is large, the light spring 502 is compressed, each baffle 5011 of the conical telescopic steel sheet 501 can be unfolded to increase the diameter of the small-diameter end, the material passing area of the material scour prevention device 50 is increased, the material is ensured to pass through smoothly, the problem of uneven impact load is solved, the material is uniformly distributed in the ball mill, and the grinding efficiency of the ball mill is improved; when the material amount is small, the light spring 502 returns to the original position, the material passing area of the material stopper 50 is reduced, and the material in the barrel 10 is ensured not to return to the feed inlet 101.
The materials pass through the material preventing device 50 from the feeding hole 101 to enter the grinding bin 20 and enter the powder selecting bin 30 from the grinding bin 20, and the materials are sorted inside and outside the powder selecting bin 30; the sorted finished products are discharged from the discharge port 102 through the dynamic powder sorting machine 310, enter the next process, and the sorted non-finished products return to the grinding bin 20 again to be ground again under the action of gravity and centrifugal force, and enter the next circulation. The self-sorting ball mill can reduce over-grinding of the ball mill, reduce fine powder agglomeration or ball pasting, improve grinding efficiency, reduce power consumption for grinding, reduce plant height, save investment cost and contribute to energy conservation and environmental protection.
The grinding system of the embodiment 1 is suitable for grinding materials with the water content of the grinding raw material being less than 2% and the granularity of the ground product being less than 80 μm, can be used for processing materials such as raw materials, cement and coal powder in the field of building materials, and can also be used for grinding ultrafine materials in the field of non-metallic ores, such as ground calcium carbonate and talcum powder.
Example 2
Referring to fig. 7 to 9, different from embodiment 1, a static powder concentrator 320 is further disposed in the powder concentrator 30 of this embodiment, and the static powder concentrator 320 is located between the main partition plate 40 and the dynamic powder concentrator 310.
The static powder concentrator 320 comprises static blades 321, the static blades 321 are arranged in a conical shape, the included angle between the static blades 321 and the axis of the cylinder 10 is 45-65 degrees, the diameter of the conical section of the static blades 321 is gradually increased from the grinding bin 20 side to the powder concentration bin 30 side, one end of the static blades 321 close to the grinding bin 20 is fixed on the main partition board 40, the other end of the static blades 321 is fixed on the cylinder 10, specifically, the other end of the static blades 321 is fixed on an inclined lining board 301 in the powder concentration bin 30, and the connection positions are connected in a welding mode. The length of the static blades 321 in the axial direction accounts for 15-25% of the length of the powder selecting bin 30, the width of each static blade 321 is 50-300 mm, and the gap between every two adjacent static blades 321 is 50-400 mm.
At this time, the inner region where the main partition plate 40 and the tapered static blades 321 intersect is a blind plate, the vent holes 401 are not provided, the outer region is provided with a grid gap, and the structure of the grid gap is the same as the structure of the grid gap 402 on the main partition plate 40 in embodiment 1.
After the materials enter the powder selecting bin 30 from the grinding bin 20, first powder selection is carried out on the conical static blades 321, then the fine powder passing through the static blades 321 is subjected to second selection through the dynamic powder selecting machine 310, the finished products after the second selection are products, and the semi-coarse powder not passing through the rotor 311 returns to the grinding bin 20 again to enter the next circulation.
Example 3
Referring to fig. 10 to 12, unlike embodiment 1, the powder selecting bin 30 of this embodiment is not provided with the dynamic powder selecting machine 310, but is provided with the static powder selecting machine 320. The ratio of the length of the powder selecting bin 30 to the length of the whole ball mill cylinder 10 is 15-40%.
The static blades 321 of the static powder concentrator 320 are arranged parallel to the axis of the barrel 10, one end of the static blade 321 close to the grinding bin 20 is fixed on the main partition board 40, the other end of the static blade 321 is fixed on the barrel 10, the connection positions are all connected in a welding mode, and the static blade 321 occupies the whole powder concentrating bin 30. The width of each static vane 321 is 50-300 mm, and the gap between two adjacent static vanes 321 is 100-400 mm. The static blades 321 rotate along with the cylinder 10 to perform the function of coarse screening of materials.
At this time, the inner region where the main partition plate 40 intersects with the static blades 321 is a blind plate, and the outer region is provided with a grid seam which is a long strip grid seam.
In this embodiment, only the static powder concentrator 320 is provided, so that the whole ball mill can be arranged in a symmetrical structure, and materials can be fed from two ends of the ball mill and discharged from the middle of the ball mill.
In addition, the static blades 321 of the static powder concentrator 320 in this embodiment may also be arranged in a conical arrangement.
The materials respectively pass through the material guards 50 from the material inlets 101 at the two ends and enter the corresponding grinding bins 20, and the ground materials enter the powder selecting bin 30 along with the airflow; the static blades 321 in the powder selecting bin 30 are horizontally arranged, the fine materials after being selected enter finished products along with airflow and are discharged from the discharge port 102, and the coarse materials return to the grinding bin 20 and enter the next cycle until the finished products are obtained. The present embodiment further provides a dust collecting opening 103 above the discharging opening 102 for collecting dust.
The self-sorting ball mill of the embodiment 4 is suitable for materials with the water content of the grinding raw materials less than 2% and the granularity of the ground products more than 80 μm, can be used for processing materials such as machine-made sand in the field of building materials, and can also be used for producing medium and fine ores in the field of mineral separation.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: it is to be understood that modifications may be made to the teachings of the foregoing embodiments, or equivalents may be substituted for some or all of their features, without departing from the scope of the embodiments of the present invention.