A tower mill batch pad grinding system and method of grinding

Abstract

The application discloses a tower mill intermittent filling and grinding system and a grinding method, and belongs to the technical field of tower mill system. The system comprises a tower mill, a feeding assembly and a discharging assembly. The tower mill is provided with a feeding port located at the upper part and a discharging port located at the lower part on the casing of the tower mill. The feeding port and the discharging port are located at the two sides of the casing of the tower mill. The discharging port is connected with the discharging assembly, and the feeding port is connected with the feeding assembly. The casing of the tower mill is also provided with a circulating port one and a circulating port two. The circulating port one is located at the upper side of the circulating port two and at the same side of the casing. A circulating pump is arranged between the circulating port one and the circulating port two, and the two ends of the circulating pump are connected through connecting pipelines. Compared with the open-circuit grinding system and the closed-circuit grinding system, the application solves the technical problem that the fine grinding system cannot meet the special working condition requirements of the client end, such as special medium, high-quality concentration medium and other rare processes, and the product processing particle size cannot meet the requirements of the open-circuit grinding system.

Description

Technical Field

[0001] The invention provides a tower mill intermittent filling grinding system and a grinding method, belonging to the technical field of tower mill systems. Background Art

[0002] Compared to other grinding equipment, tower mills offer unique advantages, including energy saving, fine and ultrafine grinding, over-grinding prevention, noise reduction, and a small footprint. In recent years, they have been widely adopted in Chinese mines, with a trend toward larger equipment sizes. With the increasing scale of stirred ball mills and the continuous improvement of stirred ball mill technology, stirred ball tower mills will become increasingly common in regrinding or fine grinding operations in metal mines.

[0003] The tower mill includes a casing, a stirring screw, a driving device and a grinding medium. The stirring screw is inside the casing and is driven by a driving device on the top of the casing. The grinding media include ball media, rod media and other special-shaped media, the most common of which is ball media.

[0004] At present, most of the mine fine grinding systems adopt closed-circuit grinding systems with tower mill + cyclone classification, such as Figure 1 As shown, another example is the prior art CN201821538260.4 high-efficiency tower mill-cyclone closed-circuit grinding system. The basic principle of this system is that during the operation of the tower mill stirring screw, the centrifugal force, gravity, and friction force cause the pulverizing medium and the material to realize an orderly movement cycle. The speed of the spiral rises in the stirring screw at a speed less than the lifting speed, and the speed of the spiral descends between the inner lining and the outer edge of the spiral. The qualified material is transported by rising with the conveying medium, and after being graded inside the tower mill cylinder, it overflows from the upper part of the tower mill cylinder by gravity. After the material overflows, it is pumped into the cyclone for classification. The qualified material overflows from the cyclone and is directly added to the next process as a product. The unqualified material is sanded and re-enters the tower mill feed port. The closed-circuit grinding system is widely used due to its high grinding efficiency and mature grinding technology.

[0005] However, in some special processes and working conditions, such as special medium slurry and high-quality concentration slurry, the cyclone cannot be used in conjunction to achieve the classification effect, and only open circuit grinding can be used. In this way, the energy-saving and fine grinding advantages of the tower mill cannot be reflected, and even the fine grinding particle size requirements cannot be achieved.

[0006] Due to the differences in mineral processing technology among various mineral processing plants, some mineral processing technologies cannot be effectively matched with cyclone classification, so the tower mill closed-circuit grinding system cannot be used normally.

[0007] Use open circuit grinding systems, such as Figure 2 As shown, the product processing particle size does not meet the requirements.

[0008] In view of this, the present invention is proposed. Summary of the Invention

[0009] In order to solve the above technical problems, the basic concept of the technical solution adopted by the present invention is:

[0010] A tower mill intermittent turbulent grinding system comprises a tower mill, a feeding assembly and a discharging assembly;

[0011] The tower mill housing is provided with an upper feed port and a lower discharge port, the feed port and the discharge port are located on both sides of the tower mill housing, the discharge port is connected to the discharge assembly, and the feed port is connected to the feed assembly;

[0012] The tower mill housing is further provided with a circulation port 1 and a circulation port 2, wherein the circulation port 1 is located above the circulation port 2 and on the same side of the housing;

[0013] A circulation pump is installed between the circulation port 1 and the circulation port 2, and the two ends are connected through a connecting pipe.

[0014] In a further technical solution, the casing is double-layered and filled with cooling water, a cooling water inlet is provided at the bottom of the circulation port 2, and a cooling water outlet is provided on the casing at the top of the discharge port.

[0015] In a further technical solution, the feed assembly includes a stirring barrel and a feed pump, wherein the stirring barrel is suitable for storing and stirring the raw ore slurry;

[0016] The mixing barrel is provided with an outlet end, and the two ends of the feed pump are respectively provided with an inlet end and an outlet end. The outlet end of the mixing barrel is connected to the inlet end of the feed pump through a connecting pipe, and the outlet end of the feed pump is connected to the feed port through a connecting pipe.

[0017] In a further technical solution, a check valve is further installed on the connecting pipe between the outlet end of the feed pump and the feed port.

[0018] In a further technical solution, the discharging assembly includes a ball removal device, a discharge valve and a discharge pump, the ball removal device is provided with an inlet end and an outlet end, the discharge port is connected to the inlet end of the ball removal device through a connecting pipe, the tower mill is provided with a stirring spiral and a ball medium, and the ball removal device is suitable for retaining the ball medium in the tower mill;

[0019] The outlet end of the ball removal device is connected to the discharge pump through a connecting pipe. A discharge valve is also installed on the connecting pipe. The discharge pump is also provided with an outlet end suitable for discharging the raw ore pulp in the casing.

[0020] In a further technical solution, a liquid level sensor is further installed on the top of the casing of the tower mill, and the liquid level sensor is suitable for detecting the liquid level in the casing.

[0021] In a further technical solution, the circulation port is located at the lower side of the feed port.

[0022] A tower mill intermittent filling grinding system includes the following steps:

[0023] S1. Feeding front: The mixing barrel at the feeding front continuously stirs the incoming raw ore slurry; the effective volume of the mixing barrel is larger than the single grinding volume of the tower mill, and the discharge port of the mixing barrel is located at the bottom of the mixing barrel to prevent the residual material in the mixing barrel from settling and compacting;

[0024] The discharge port of the mixing barrel is equipped with a feed valve, which is in a normally closed state. The grinding feed is controlled by the time and duration set by the external control program to open the feed valve;

[0025] S2. Feeding stage: The mixing barrel at the front end of the feed operates normally to store the ore slurry, and the feed valve is opened by an external control program;

[0026] The raw ore slurry is pumped to the feed port through the feed pump. During the feeding process, the signal from the liquid level sensor is used to monitor whether the ore slurry in the tower mill is full.

[0027] S3. If the liquid level sensor in step S2 detects that the liquid level is full, the signal is transmitted through the external control program to first turn off the feed pump, then close the feed valve, and then block the backwash of the slurry from damaging the feed pump through the check valve;

[0028] During the feeding stage, the discharge valve and discharge pump are in a normally closed state;

[0029] S4. Grinding stage: During the grinding stage, the feed valve and feed pump are both in the normally closed state, and the discharge valve and discharge pump are both in the normally closed state;

[0030] The external control program is used to set and control the tower mill's filling and grinding time. During the grinding process, in order to avoid over-grinding of the ore slurry in the middle and lower part of the cylinder and under-grinding of the ore slurry in the upper part of the tower mill, the grinding index cannot meet the set requirements. Therefore, during the grinding process, the circulating pump is always in operation to force the suspended ore slurry in the upper part of the cylinder to be pumped into the bottom of the cylinder, so that the ore slurry inside the cylinder is evenly ground to avoid over-grinding or under-grinding of the ore slurry.

[0031] S5. Discharge stage: After the grinding time reaches the programmed value, the discharge valve is opened and the discharge pump is operated to discharge the ore slurry and add it to the next process flow;

[0032] During the discharge process, a ball removal device is installed between the discharge port and the discharge valve;

[0033] The ball removal device is provided with a large-hole screen and a small-hole screen on both sides, the large-hole screen is suitable for being close to the discharge port of the tower mill, and the small-hole screen is suitable for being close to the discharge valve.

[0034] S6. After the discharging is completed, the step S1 of feeding the front end is repeated, and the operation of S1-S5 is recycled again.

[0035] In a further technical solution, the model selection and the circulating pump flow are as follows:

[0036] Q = V / (T / 5) ;

[0037] Q is the rated flow of the circulating pump (m3 / h) ; V is the single effective grinding volume (m3) ; and T is the single actual grinding time (h).

[0038] The effective volume of the stirring barrel = (1.2-1.5) * the single grinding volume of the tower mill.

[0039] The ball removal device is provided with a large-hole screen and a small-hole screen on both sides, the large-hole screen is suitable for being close to the discharge port of the tower mill, and the small-hole screen is suitable for being close to the discharge valve.

[0040] Beneficial effects:

[0041] The present application relates to a kind of intermittent smothered filling grinding system of tower mill, this kind of tower mill fine grinding system overcomes the severe dependence of tower mill under partial working condition on cyclone selection limit, does not utilize traditional tower mill overflow principle, in the advantages of retaining tower mill high efficiency energy saving and superfine grinding, using whole cylinder pumping feeding, whole cylinder smothered filling fine grinding, whole cylinder pumping discharge continuous single cycle grinding mode.

[0042] The grinding system can meet the special working condition and special process requirement of customer end under the premise of maintaining the advantages of tower mill energy saving, superfine grinding and preventing overgrinding, and plays a good complementary role for the promotion and use of tower mill in mine.

[0043] Compared with closed circuit grinding system, the operating system overcomes the matching limit of cyclone, has great popularization value and practical performance; compared with open circuit grinding system, has the advantages of energy saving and consumption reduction and superfine grinding.

[0044] 1, closed circuit grinding system cannot be used in high quality concentration grinding medium working condition, intermittent smothered filling grinding system gets rid of the dependence on cyclone centrifugal classification treatment, and can meet the special working condition and special process requirement of customer end.

[0045] 2. The open circuit grinding system does not have the ability to evenly distribute the ultra-fine grinding particle size. The intermittent filling grinding system can easily exert the ultra-fine grinding function of the tower mill by controlling the grinding time.

[0046] 3. The intermittent filling grinding system has the advantages of energy saving, consumption reduction and over-grinding prevention of tower mill. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0048] Figure 1 This is a schematic diagram of a closed circuit grinding system;

[0049] Figure 2 This is a schematic diagram of the open circuit grinding system;

[0050] Figure 3 This is a schematic diagram of the intermittent filling and grinding operation system of the present invention.

[0051] In the figure: 1. Tower mill; 2. Circulation pump; 3. Connecting pipe; 4. Mixing barrel; 5. Feed pump; 6. Check valve; 7. Ball removal equipment; 8. Discharge valve; 9. Discharge pump; 10. Liquid level sensor; 11. Feed port; 12. Discharge port; 13. Circulation port 1; 14. Circulation port 2; 15. Cooling water inlet; 16. Cooling water outlet; 17. Casing; 18. Mixing screw; 20. Feed valve; 21. Large-hole screen; 22. Small-hole screen; 23. Crankshaft. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0053] The application principle of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0054] Figure 1 For closed circuit grinding system:

[0055] After the tower mill grinds the ore pulp, the processed product overflows from the top of the cylinder into the mixing barrel and is pumped to the cyclone for centrifugal classification along with the newly added raw ore pulp. Qualified particle size products overflow directly into the next step, while unqualified materials settle and re-enter the tower mill feed port for re-grinding, continuing the cycle. Closed-circuit grinding uses a tower mill with a cyclone. The entire process is mature and widely used. As long as the tower mill and cyclone are correctly selected and matched, the tower mill can fully utilize its advantages such as high efficiency and energy saving, prevention of over-grinding, and ultra-fine grinding.

[0056] Disadvantages of closed-circuit grinding system: The disadvantage of this system is that when the cyclone cannot match the centrifugal classification treatment of high-concentration slurry, the entire grinding system cannot continue to operate normally.

[0057] Figure 2 For open circuit grinding system:

[0058] The entire grinding system is relatively simple. The new ore slurry is directly pumped to the feed port of the tower mill through the mixing barrel. Relying on the automatic classification function of the tower mill itself, the qualified material directly overflows from the upper end of the cylinder and no longer passes through the cyclone for further classification and mineral separation. This grinding system, due to uneven flow control at the feed end, easily leads to large particles of material directly overflowing as finished products without being fully ground, so the ground particle size often does not meet the client's fine grinding requirements.

[0059] Disadvantages of open circuit grinding system: It relies solely on the overflow classification of the medium in the tower mill cylinder by its own weight, resulting in poor grinding effect. The product is easily mixed with large particles of incompletely ground materials, and the product particle size is difficult to meet the requirements.

[0060] Example 1

[0061] like Figure 3 As shown, a tower mill intermittent filling grinding system includes a tower mill 1, a feed assembly, and a discharge assembly. The tower mill 1 is provided with a feed port 11 at the top and a discharge port 12 at the bottom on the housing 17. The feed port 11 and the discharge port 12 are located on either side of the tower mill 1 housing 17. The discharge port 12 is connected to the discharge assembly, and the feed port 11 is connected to the feed assembly. The tower mill 1 is also provided with a circulation port 13 and a circulation port 2 14 on the housing 17. The circulation port 13 is located above the circulation port 2 14 and on the same side of the housing 17. A circulation pump 2 is installed between the circulation port 13 and the circulation port 2 14, and the two ends are connected by a connecting pipe 3. The circulation port 13 is located below the feed port 11.

[0062] The casing 17 is double-layered and filled with cooling water. A cooling water inlet 15 is provided at the bottom of the second circulation port 14 , and a cooling water outlet 16 is provided on the casing 17 at the top of the discharge port 12 .

[0063] The feed assembly includes a mixing barrel 4 and a feed pump 5. The mixing barrel 4 is suitable for storing and stirring the raw ore slurry. The mixing barrel 4 is provided with an outlet end, and the feed pump 5 is provided with an inlet end and an outlet end at both ends. The outlet end of the mixing barrel 4 is connected to the inlet end of the feed pump 5 via a connecting pipe 3, and the outlet end of the feed pump 5 is connected to the feed port 11 via a connecting pipe 3. A check valve 6 is also installed on the connecting pipe 3 between the outlet end of the feed pump 5 and the feed port 11.

[0064] The discharge assembly includes a ball removal device 7, a discharge valve 8, and a discharge pump 9. The ball removal device 7 has an inlet and an outlet. The discharge port 12 is connected to the inlet of the ball removal device 7 via a connecting pipe 3. The tower mill 1 is equipped with a stirring screw 18 and a ball medium (the ball medium is not shown in the figure). The ball removal device 7 is suitable for retaining the ball medium in the tower mill 1. The outlet of the ball removal device 7 is connected to the discharge pump 9 via a connecting pipe 3. The connecting pipe 3 is also equipped with a discharge valve 8. The discharge pump 9 is also equipped with an outlet suitable for discharging the raw ore slurry from the casing 17. A liquid level sensor 10 is also installed on the top of the casing 17 of the tower mill 1. The liquid level sensor 10 is suitable for detecting the liquid level within the casing 17. A conventional liquid level sensor 10 can be used, with the detection end located within the casing 17 for detection. The signal is converted into an analog signal and transmitted via a signal line to the PLC. The PLC converts the analog signal into an electrical signal to determine and control the on / off of the circulation pump 2 and the feed pump 5.

[0065] A tower mill intermittent filling grinding system includes the following steps:

[0066] S1. Feed front end: The mixing barrel 4 at the front end of the feed keeps stirring the raw ore slurry; the effective volume of the mixing barrel 4 is larger than the single grinding volume of the tower mill 1, and the discharge port of the mixing barrel 4 is located at the bottom of the mixing barrel 4 to avoid sedimentation and hardening of the residual material in the mixing barrel 4;

[0067] The discharge port of the mixing barrel 4 is equipped with a feed valve 20, which is in a normally closed state. The grinding feed is controlled by an external control program to set the time and duration, and the feed valve 20 is opened;

[0068] S2 feeding stage: the feeding front end mixing barrel 4 normal operation of the storage slurry, the feed valve 20 is opened by an external control program;

[0069] The raw ore pulp is delivered to the feed port 11 by the feed pump 5. During the feeding process, the signal from the liquid level sensor 10 is used to monitor whether the ore pulp in the tower mill 1 is full.

[0070] S3. If the liquid level sensor 10 in step S2 detects that the liquid level is full, the signal is transmitted through the external control program to first close the feed pump 5, then close the feed valve 20, and block the backwash of the slurry through the check valve 6 to damage the feed pump 5;

[0071] During the feeding stage, the discharge valve 8 and the discharge pump 9 are in a normally closed state;

[0072] S4 grinding stage: grinding stage, the feed valve 20, the feed pump 5 are in the normally closed state, the discharge valve 8 and the discharge pump 9 are normally closed;

[0073] The external control program is used to set and control the filling and grinding time of tower mill 1. During the grinding process, in order to avoid over-grinding of the ore slurry in the middle and lower part of the cylinder and under-grinding of the ore slurry in the upper part of tower mill 1, the grinding index cannot meet the set requirements. Therefore, during the grinding process, the circulation pump 2 is always in operation to force the suspended ore slurry in the upper part of the cylinder to be pumped into the bottom of the cylinder, so that the ore slurry inside the cylinder is evenly ground to avoid over-grinding or under-grinding of the ore slurry.

[0074] S5. Discharge stage: After the grinding time reaches the program setting value, open the discharge valve 8, run the discharge pump 9, and discharge the slurry to join the next process;

[0075] During the discharge process, a ball removal device 7 is provided between the discharge port 12 and the discharge valve 8;

[0076] like Figure 4 As shown, both sides of the ball removal device 7 are provided with partitions of different apertures, including a large-pore partition 21 and a small-pore partition 22. The large-pore partition 21 is suitable for being close to the tower mill discharge port 12, and the small-pore partition 22 is suitable for being close to the discharge valve 8. The ball discharge port at the bottom of the ball removal device 7 is opened regularly to empty the ball medium stored in the ball removal device 7 and put it back into the tower mill 1; an oblique angle is provided in the ball removal device 7 to prevent the ball medium from forming a blockage between the large-pore partition 21 and the inner wall of the ball removal device 7.

[0077] S6. After the discharge is completed, repeat step S1 to feed the front end, and cycle through operations S1 to S5 again.

[0078] Model selection, circulation pump flow:

[0079] Q = V / T / 5;

[0080] Q is the rated flow of the circulating pump in m³ / h; V is the effective grinding volume in a single pass in m³; T is the actual grinding time in a single pass in h;

[0081] The effective volume of the mixing barrel 4 = (1.2-1.5) * the single grinding volume of the tower mill.

[0082] Example 2

[0083] like Figure 5FIG. 2 is another embodiment of the present invention. Based on Example 1, a vertically mounted crankshaft 23 is installed in the ball removal device 7. The crankshaft 23 is installed between the large-pore screen 21 and the small-pore screen 22. Both the large-pore screen 21 and the small-pore screen 22 are vertically arranged. The crankshaft 23 is adapted to rotate in the ball removal device 7 to prevent the ball media from being blocked outside the large-pore screen 21. The top of the crankshaft 23 can extend to the outer end of the ball removal device 7 to install a motor to realize the rotation of the crankshaft 23.

[0084] Working principle:

[0085] Intermittent filling grinding system:

[0086] Feeding: Intermittent filling mill, the tower mill body always maintains normal operation state, the mixing barrel 4 serves as a container for storing incoming materials, turn on the feed pump 5, and the raw ore slurry is directly sent to the feed port 11 on the upper part of the tower mill 1 cylinder through the mixing barrel 4 using the feed pump 5. The liquid level sensor 10 monitors whether the ore slurry in the tower mill 1 cylinder is full. If it is full, the feed pump 5 is closed through the PLC program control.

[0087] Grinding: The discharge valve 8 remains closed, and the tower mill is stuffy and grinding for a fixed time. During the grinding process, in order to avoid over-grinding of the ore slurry in the middle and lower part of the cylinder and loss of power consumption, the circulating pump 2 is in working state, forcing the suspended ore slurry in the upper part of the cylinder to be pumped into the bottom of the cylinder, so that the ore slurry inside the cylinder is evenly ground and over-grinding of the ore slurry at the bottom of the cylinder is avoided.

[0088] The heat generated during the grinding process cannot be taken away by continuous discharge like the aforementioned closed-circuit or open-circuit system grinding. Therefore, the intermittent turbid mill needs to add a cooling device on the outside of the cylinder, and use cooling water from the bottom in and out to cool down and remove the grinding heat, thereby reducing the slurry temperature in the cylinder.

[0089] Discharge: The tower mill 1 is in normal operation. When the grinding time is up, the discharge valve 8 is opened and the discharge pump 9 is operated to discharge the finished slurry from the cylinder directly through the discharge pump 2. During the discharge process, a ball removal device 7 is added to the discharge port 12 to prevent the ball media inside the cylinder from being discharged with the material.

[0090] After the discharge is completed, repeat the first step of feeding and operate in a single cycle again.

[0091] Comparison of three grinding systems:

[0092] Compared with the closed-circuit grinding system: the conventional closed-circuit grinding system cannot be used in high-concentration slurry media due to the cyclone. The intermittent filling grinding operation system gets rid of the dependence on the centrifugal classification treatment of the cyclone and can meet the client's special working conditions and special process requirements.

[0093] Table 1. Differences in the effects of different grinding systems:

[0094]

[0095] Comparison of open circuit grinding systems: The open circuit grinding system has poor grinding effect, the product is easily mixed with large particles of incompletely ground materials, and the product particle size cannot meet the requirements. The intermittent filling grinding operating system can meet the client's special working conditions and special process requirements while ensuring the advantages of tower mill such as energy saving, ultrafine grinding and prevention of over-grinding.

[0096] Comparison of client usage effects:

[0097] The feed medium is iron ore, the feed mass concentration is 65%, the feed particle size is -200 mesh 50%, and the processing capacity is 35t / h.

[0098] Product particle size requirement: -325 mesh 90%.

[0099] Table 2. Comparison of sampling data for different grinding systems:

[0100]

[0101] According to the test grinding data recorded in the table above, the particle size of open circuit grinding -325 mesh is only 66.5%, while the closed circuit grinding can reach 91.2%. The particle size of open circuit grinding cannot meet the use requirements.

[0102] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations that come within the meaning and range of equivalents of the claims be embraced therein.

[0103] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A tower mill intermittent filling grinding system, characterized in that: It comprises a tower mill (1), a feeding assembly and a discharging assembly; The tower mill (1) is provided with a feed port (11) at the upper portion and a discharge port (12) at the lower portion on the housing (17). The feed port (11) and the discharge port (12) are located on both sides of the tower mill (1) housing (17). The discharge port (12) is connected to the discharge assembly, and the feed port (11) is connected to the feed assembly. The tower mill (1) is provided with a first circulation port (13) and a second circulation port (14) on the housing (17), wherein the first circulation port (13) is located above the second circulation port (14) and on the same side of the housing (17); A circulation pump (2) is installed between the circulation port 1 (13) and the circulation port 2 (14), and the two ends are connected via a connecting pipe (3); The following steps are also included: S1. Feed front end: The mixing barrel (4) at the feed front end continuously stirs the incoming raw ore slurry; the effective volume of the mixing barrel (4) is greater than the single grinding volume of the tower mill (1), and the discharge port of the mixing barrel (4) is located at the bottom of the mixing barrel (4) to prevent the residual material in the mixing barrel (4) from settling and hardening; The discharge port of the mixing barrel (4) is equipped with a feed valve (20), which is in a normally closed state. The grinding feed is controlled by an external control program to set the time and duration, and the feed valve (20) is opened; S2. Feeding stage: The feeding front end mixing barrel (4) operates normally to store the ore slurry, and the feed valve (20) is opened by an external control program; The raw ore pulp is delivered to the feed port (11) through the feed pump (5). During the feeding process, the signal of the liquid level sensor (10) is used to monitor whether the ore pulp in the tower mill (1) is full. S3. If the liquid level sensor (10) in step S2 detects that the liquid level is full, the signal is transmitted and the external control program is used to first close the feed pump (5), then close the feed valve (20), and then block the backwash of the slurry through the check valve (6) to damage the feed pump (5); During the feeding stage, the discharge valve (8) and the discharge pump (9) are in a normally closed state; S4. Grinding stage: During the grinding stage, the feed valve (20) and the feed pump (5) are both in a normally closed state, and the discharge valve (8) and the discharge pump (9) are both in a normally closed state; The external control program is used to set and control the filling and grinding time of the tower mill (1). During the grinding process, in order to avoid the over-grinding of the ore slurry in the middle and lower part of the cylinder, the under-grinding of the ore slurry in the upper part of the tower mill (1), and the failure of the grinding index to meet the set requirements, the circulating pump (2) is always in operation during the grinding process, forcing the suspended ore slurry in the upper part of the cylinder to be driven into the bottom of the cylinder, so that the ore slurry inside the cylinder is evenly ground, avoiding the over-grinding or under-grinding of the ore slurry; S5. Discharge stage: After the grinding time reaches the programmed value, the discharge valve (8) is opened, the discharge pump (9) is operated, and the slurry is discharged to join the next process flow; During the discharge process, a ball removal device (7) is provided between the discharge port (12) and the discharge valve (8); The two sides of the ball removal device (7) are provided with screens with different apertures, including a large-pore screen (21) and a small-pore screen (22). The large-pore screen (21) is suitable for being close to the discharge port (12) of the tower mill, and the small-pore screen (22) is suitable for being close to the discharge valve (8). The ball discharge port at the bottom of the ball removal device (7) is opened regularly to empty the ball medium stored in the ball removal device (7) and put it back into the tower mill (1); S6. After the discharge is completed, repeat step S1 to feed the front end, and cycle through operations S1 to S5 again.

2. The intermittent filling and grinding system of a tower mill according to claim 1 is characterized in that: The casing (17) is double-layered and filled with cooling water. A cooling water inlet (15) is provided at the bottom of the second circulation port (14), and a cooling water outlet (16) is provided on the casing (17) at the top of the discharge port (12).

3. The intermittent filling and grinding system of a tower mill according to claim 1 is characterized in that: The feed assembly comprises a stirring barrel (4) and a feed pump (5), and the stirring barrel (4) is suitable for storing and stirring raw ore slurry; The stirring barrel (4) is provided with an outlet end, and the two ends of the feed pump (5) are respectively provided with an inlet end and an outlet end. The outlet end of the stirring barrel (4) is connected to the inlet end of the feed pump (5) via a connecting pipe (3), and the outlet end of the feed pump (5) is connected to the feed port (11) via a connecting pipe (3).

4. The intermittent filling and grinding system of a tower mill according to claim 3 is characterized in that: A check valve (6) is also installed on the connecting pipe (3) between the outlet end of the feed pump (5) and the feed port (11).

5. The intermittent filling and grinding system of a tower mill according to claim 1 is characterized in that: The discharge assembly comprises a ball removal device (7), a discharge valve (8) and a discharge pump (9); the ball removal device (7) is provided with an inlet end and an outlet end; the discharge port (12) is connected to the inlet end of the ball removal device (7) via a connecting pipe (3); a stirring screw (18) and ball media are provided in the tower mill (1); the ball removal device (7) is suitable for retaining the ball media in the tower mill (1); The outlet end of the ball removal device (7) is connected to the discharge pump (9) by installing a connecting pipe (3), and a discharge valve (8) is also installed on the connecting pipe (3). The discharge pump (9) is also provided with an outlet end suitable for discharging the raw ore pulp in the casing (17).

6. The intermittent filling and grinding system of a tower mill according to claim 5, characterized in that: A liquid level sensor (10) is also installed on the top of the housing (17) of the tower mill (1), and the liquid level sensor (10) is suitable for detecting the liquid level in the housing (17).

7. The intermittent filling and grinding system of a tower mill according to any one of claims 1 to 6, characterized in that: The circulation port 1 (13) is located at the lower side of the feed port (11).

8. The intermittent filling and grinding system of a tower mill according to claim 7, characterized in that: Model selection, flow specifications of circulation pump (2): Q = V / (T / 5); Q is the rated flow of the circulating pump; V is the effective grinding volume of a single time; T is the actual grinding time of a single time; The effective volume of the mixing barrel (4) = (1.2-1.5) * the single grinding volume of the tower mill.

9. The intermittent filling and grinding system of a tower mill according to claim 8, characterized in that: A vertically mounted crankshaft (23) is installed in the ball removal device (7). The crankshaft (23) is installed between the large-pore screen (21) and the small-pore screen (22). The large-pore screen (21) and the small-pore screen (22) are both vertically arranged. The crankshaft (23) is suitable for rotating in the ball removal device (7) to prevent the ball medium from being blocked outside the large-pore screen (21).

Images