Control method of semi-autogenous grinding-rock crushing circuit

Abstract

The present application provides a control method for a semi-autogenous grinding-stone crushing circuit, which belongs to the field of mining engineering technology. The main purpose is to achieve stable control of the total feed rate of the semi-autogenous grinding-stone crushing circuit, and then achieve stable operation of the circuit working condition. The main technical scheme of the present application is: the semi-autogenous grinding-stone crushing circuit includes a stone processing unit and a semi-autogenous mill, the stone processing unit can receive the stone discharged by the semi-autogenous mill, the stone processing unit includes a stone crushing system and a stone bypass system, the stone crushing system can crush the stone and discharge it back to the semi-autogenous mill, and the stone bypass system can discharge the stone back to the semi-autogenous mill; the control method includes: in response to an adjustment instruction, controlling the operating state of the stone processing unit; controlling the semi-autogenous mill to adjust the grinding efficiency.

Description

Technical Field

[0001] The present application belongs to the field of mining engineering technology, and specifically relates to a control method for a semi-autogenous grinding-rock crushing circuit. Background Art

[0002] Semi-autogenous mills have gradually become the preferred equipment in the ore dressing and grinding process due to their advantages such as large ore processing capacity, small footprint, streamlined equipment, low production cost, and low maintenance intensity. For difficult-to-grind ores, the discharge of semi-autogenous mills often contains a certain proportion of stubborn stones. In order to improve the grinding energy efficiency, it is necessary to add a stubborn stone crushing process, that is, to design a semi-autogenous mill-stubborn stone crushing circuit.

[0003] The SAG rock crushing circuit usually includes a SAG mill feeding belt conveyor, a SAG mill, a double-deck vibrating screen at the discharge end of the SAG mill, a return belt conveyor for transporting the rock on the double-deck vibrating screen, a rock buffer bin, a rock belt feeder, a rock crushing system and a crushed rock transfer belt conveyor.

[0004] The ore flow of the SAG-rock crushing circuit is as follows: ore (new feed) is fed into the SAG mill through the SAG feed belt conveyor for grinding, the SAG mill discharge is fed into the double-layer vibrating screen at the discharge end, the rock on the screen is transported to the rock buffer bin through the rock return belt conveyor, the ore under the screen enters the pump pool, the ore in the rock buffer bin is crushed by the rock crushing system and then transported to the rock crushing transfer belt through the rock belt feeder, the rock is then transported to the SAG feed belt conveyor through the rock crushing transfer belt, and is combined with the new feed into the total feed and fed into the SAG mill for grinding, forming a SAG-rock crushing circuit.

[0005] In the design process of existing rock crushing process, in order to meet the demand for rock processing volume under extreme working conditions, the selection of rock crushing system is usually too large, resulting in the rock crushing system processing capacity being greater than the rock return volume, and the rock buffer bin is very likely to reach the low material level alarm value. In order to ensure that the ore does not directly hit the rock crushing system, the rock crushing system is usually shut down according to the material level value of the rock buffer bin, and restarted when the material level of the rock buffer bin reaches the high alarm value. This working system causes the rock content in the total feed of the semi-autogenous mill to fluctuate frequently and with a large amplitude, which seriously affects the stability of the semi-autogenous mill, and then seriously affects the working stability of the grinding process, resulting in frequent and large fluctuations in working conditions, increased energy and material consumption, and low grinding efficiency.

[0006] Therefore, it is urgent to achieve stable control of the total feed rate of the semi-autogenous grinding-rock crushing circuit, and then achieve stable operation of the circuit working conditions. Summary of the invention

[0007] In view of this, the present application provides a control method for a semi-autogenous grinding-rock crushing circuit, the main purpose of which is to achieve stable control of the total ore feed rate of the semi-autogenous grinding-rock crushing circuit, thereby achieving stable operation of the circuit working condition.

[0008] In order to achieve the above objectives, this application mainly provides the following technical solutions:

[0009] The present application provides a control method for a semi-autogenous grinding mill-stone crushing circuit, wherein the semi-autogenous grinding mill-stone crushing circuit comprises a stone processing unit and a semi-autogenous grinding mill, wherein the stone processing unit is capable of receiving stones discharged from the semi-autogenous grinding mill, wherein the stone processing unit comprises a stone crushing system and a stone bypass system, wherein the stone crushing system is capable of crushing the stones and then discharging them back to the semi-autogenous grinding mill, and wherein the stone bypass system is capable of discharging the stones back to the semi-autogenous grinding mill;

[0010] The control method comprises:

[0011] In response to the adjustment instruction, controlling the operating state of the stubborn stone processing unit;

[0012] The semi-autogenous mill is controlled to adjust the grinding efficiency.

[0013] Optionally, the SAG mill-stone crushing circuit further includes a stone buffer bin, the stones discharged from the SAG mill are discharged to the stone buffer bin, and the stones in the stone buffer bin are discharged to the stone crushing system and the stone bypass system;

[0014] The control method further comprises:

[0015] Obtaining the level of the hard stone in the hard stone buffer bin;

[0016] When the rock material level continues to drop and is higher than the low level alarm value, the rock crushing system is controlled to operate, and the rock bypass system is controlled to shut down.

[0017] Optionally, after obtaining the stone material level in the stone buffer bin, the control method further includes:

[0018] When the rock material level continues to drop and is lower than the low level alarm value, the rock crushing system is controlled to stop, and the rock bypass system is controlled to start, so that the rock transfer capacity of the rock bypass system is the same as the rock processing capacity of the rock crushing system;

[0019] Obtaining the amount of stubborn rock returned from the SAG mill discharge;

[0020] When the amount of rock returned from the SAG mill is greater than the amount of rock processed by the rock crushing system, the rock bypass system is controlled to slow down so that the amount of rock transported by the rock bypass system is less than the amount of rock returned from the SAG mill;

[0021] Obtaining the level of the hard stone in the hard stone buffer bin;

[0022] When the rock material level is higher than the high alarm value, the rock crushing system is controlled to start, the rock bypass system is controlled to shut down, and the semi-autogenous mill is controlled to adjust the grinding efficiency and reduce the amount of rock returned from the semi-autogenous mill, so that the amount of rock returned from the semi-autogenous mill and the rock processing capacity of the rock crushing system maintain a dynamic balance.

[0023] Optionally, after obtaining the stone material level in the stone buffer bin, the control method further includes:

[0024] When the rock level continues to rise and is lower than the high alarm value, the rock crushing system is controlled to operate, the rock bypass system is controlled to shut down, and the semi-autogenous mill is controlled to adjust the grinding efficiency and reduce the amount of rock returned from the semi-autogenous mill, so that the amount of rock returned from the semi-autogenous mill and the rock processing capacity of the rock crushing system maintain a dynamic balance.

[0025] Optionally, after obtaining the stone material level in the stone buffer bin, the control method further includes:

[0026] When the rock level continues to rise and is higher than the high alarm value, the rock crushing system is controlled to operate, the rock bypass system is controlled to start, and the rock bypass system is controlled to adjust its working state. At the same time, the semi-autogenous mill is controlled to adjust the grinding efficiency and reduce the amount of rock returned from the semi-autogenous mill, so that the sum of the rock transfer amounts of the rock crushing system and the rock bypass system maintains a dynamic balance with the amount of rock returned from the semi-autogenous mill.

[0027] Optionally, the control method further includes:

[0028] When the rock crushing system is shut down for maintenance or failure, the rock bypass system is controlled to start and adjust its operating state, and the semi-autogenous mill is controlled to adjust its grinding efficiency to reduce the amount of rock returned from the semi-autogenous mill, so that the rock transfer volume of the rock bypass system and the amount of rock returned from the semi-autogenous mill are kept in dynamic balance.

[0029] Optionally, the SAG-rock crushing circuit further comprises a feeding belt conveyor and a rock transfer belt conveyor, wherein the rock transfer belt conveyor is capable of receiving and transferring the rock discharged from the rock crushing system and the rock bypass system to the feeding belt conveyor, and the feeding belt conveyor is capable of transferring the rock and raw ore to the SAG mill;

[0030] The control method further comprises:

[0031] Obtaining the ore processing capacity of the semi-autogenous mill;

[0032] When reducing the ore processing capacity of the semi-autogenous mill, firstly control the feeding belt conveyor to adjust the feeding frequency and reduce the feeding capacity of the feeding belt conveyor, and at the same time control the start-up of the rock bypass system, and then control the semi-autogenous mill to adjust the grinding efficiency and reduce the amount of rock returned from the semi-autogenous mill, then control the rock bypass system to slow down until it stops, and finally control the semi-autogenous mill to slow down so that the rock transfer capacity of the rock transfer belt conveyor and the rock return capacity of the semi-autogenous mill are kept in dynamic balance.

[0033] Optionally, after obtaining the ore processing capacity of the semi-autogenous mill, the control method further includes:

[0034] When the ore processing capacity of the semi-autogenous mill is increased, the feeding belt conveyor is first controlled to adjust the feeding frequency and increase the feeding capacity of the feeding belt conveyor. At the same time, the semi-autogenous mill is controlled to adjust the grinding efficiency and reduce the amount of stubborn stones returned from the discharge of the semi-autogenous mill. Then, the semi-autogenous mill is controlled to speed up its operation. Finally, the feeding belt conveyor and the semi-autogenous mill are controlled to be stable in frequency.

[0035] Optionally, the control method further includes:

[0036] Obtaining the amount of stubborn rock returned from the SAG mill and the ore processing capacity of the SAG mill;

[0037] When the amount of rock returned from the semi-autogenous mill is less than the rock processing capacity of the rock crushing system within the first time, the rock crushing system is controlled to shut down, and the rock bypass system is controlled to start. At the same time, the semi-autogenous mill is controlled to adjust the grinding efficiency to reduce the amount of rock returned from the semi-autogenous mill, and the rock bypass system is controlled to adjust its working state, so that the sum of the rock transfer volumes of the rock crushing system and the rock bypass system maintains a dynamic balance with the ore processing capacity of the semi-autogenous mill.

[0038] Optionally, after obtaining the amount of stubborn rock returned from the SAG mill and the ore processing amount of the SAG mill, the control method further includes:

[0039] When the amount of rock returned from the semi-autogenous mill is greater than the rock processing capacity of the rock crushing system within the first time, the rock crushing system is controlled to operate, the rock bypass system is controlled to start, and the semi-autogenous mill is controlled to adjust the grinding efficiency to reduce the amount of rock returned from the semi-autogenous mill, and the rock bypass system is controlled to adjust its working state, so that the sum of the rock transfer volumes of the rock crushing system and the rock bypass system maintains a dynamic balance with the ore processing capacity of the semi-autogenous mill.

[0040] By means of the above technical solution, the present application has at least the following beneficial effects:

[0041] The control method of the semi-autogenous grinding-pebble crushing circuit provided in the embodiment of the present application can effectively cope with the changes in the material level of the pebble buffer bin through the coordinated control of the pebble processing unit (including the pebble crushing system and the pebble bypass system) and the semi-autogenous grinding mill. Specifically, when the rock level continues to drop and is higher than the low alarm value, the rock crushing system is controlled to operate and the rock bypass system is shut down, so that the rock processing path can be reasonably allocated according to the material level, avoiding the rock amount fluctuation problem caused by the large selection of rock crushers in the prior art, and realizing stable control of the total feed amount of the semi-autogenous mill-rock crushing circuit; when the rock level continues to drop and is lower than the low alarm value, by controlling the rock crushing system to stop and the rock bypass system to start, and matching the transfer amounts of the two, combined with the monitoring and control of the rock return amount of the semi-autogenous mill discharge, it is possible to ensure reasonable processing of the rock amount under low material level conditions and prevent large fluctuations in the total feed amount; when the rock level is higher than the high alarm value or continues to rise, through comprehensive control of the rock crushing system, the rock bypass system and the semi-autogenous mill, such as adjusting the grinding efficiency, adjusting the rock transfer amount and other operations, the rock transfer amount and the rock return amount of the semi-autogenous mill discharge are kept in dynamic balance. This helps to maintain the stability of the semi-autogenous mill, avoids the problem of frequent fluctuations in the grinding process conditions caused by frequent and large fluctuations in the amount of stubborn rock in the prior art, and thus ensures the stable operation of the entire grinding process conditions; when the stubborn rock crushing system is shut down for maintenance or failure, the stubborn rock bypass system can be controlled to start and adjust the operating state in time, and the grinding efficiency of the semi-autogenous mill can be adjusted at the same time, so that the stubborn rock transfer amount of the stubborn rock bypass system and the stubborn rock return amount of the semi-autogenous mill discharge are balanced. In this way, when there is a problem with the equipment, the normal operation of the semi-autogenous mill-stubborn rock crushing circuit can still be guaranteed, reducing the impact of equipment failure on production; when adjusting the ore processing capacity of the semi-autogenous mill, through the sequential control of the feeding belt conveyor, the stubborn rock bypass system, the semi-autogenous mill and other equipment, such as first adjusting the feeding frequency of the feeding belt conveyor, and then controlling the semi-autogenous mill and the stubborn rock bypass system, etc., the stubborn rock transfer amount of the stubborn rock transfer belt conveyor and the stubborn rock return amount of the semi-autogenous mill discharge can be kept in dynamic balance. This makes the adjustment of ore processing volume more flexible, and the balance of the entire circuit can be maintained during the adjustment process, improving the system's adaptability to different production needs. In addition, by obtaining the return amount of stubborn rock from the SAG mill and the ore processing volume of the SAG mill, and performing corresponding control at different times according to the size relationship between the two, such as controlling the start and stop of the stubborn rock crushing system and the stubborn rock bypass system and adjusting the working state, the stubborn rock transfer volume and the ore processing volume of the SAG mill are kept balanced. This dynamic balance control method can effectively improve grinding efficiency, reduce energy and material consumption, and avoid the problem of low production efficiency caused by the imbalance between stubborn rock volume and ore processing volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1This is a schematic structural diagram of a semi-autogenous grinding-stone crushing circuit of an optional embodiment of the present application.

[0043] The reference numerals are:

[0044] 1. Semi-autogenous grinding mill; 2. Rock crushing system; 21. First belt feeder; 22. Rock crusher; 3. Rock bypass system; 31. Second belt feeder; 4. Rock buffer bin; 5. Level meter; 6. Feeding belt conveyor; 7. Rock return belt conveyor; 8. Rock transfer belt conveyor; 9. Automatic ball adding machine; 10. First electronic belt scale; 11. Second electronic belt scale; 12. Third electronic belt scale; 13. Fourth electronic belt scale; 14. Coarse ore pile; 15. Vibrating feeder; 16. Double-layer vibrating screen. DETAILED DESCRIPTION

[0045] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0046] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0047] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0048] The preferred embodiments of the present application are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present application and are not used to limit the present application.

[0049] According to an embodiment of the present application, a control method for a semi-autogenous grinding-rock crushing circuit is provided, which is used to achieve stable control of the total ore feed rate of the semi-autogenous grinding-rock crushing circuit, thereby achieving stable operation of the circuit working condition.

[0050] Among them, see Figure 1 As shown, the semi-autogenous grinding-stone crushing circuit includes a stone processing section, a semi-autogenous grinding mill 1, a stone buffer bin 4, a material level meter 5, a feeding belt conveyor 6, a stone return belt conveyor 7, a stone transfer belt conveyor 8, an automatic ball adding machine 9, a first electronic belt scale 10, a second electronic belt scale 11, a third electronic belt scale 12, a fourth electronic belt scale 13, a coarse ore pile 14, a vibrating feeder 15 and a double-layer vibrating screen 16.

[0051] The rock processing section includes a rock crushing system 2 and a rock bypass system 3 .

[0052] The rock crushing system 2 includes a first belt feeder 21 and a rock crusher 22 .

[0053] The rock bypass system 3 includes a second belt feeder 31 .

[0054] Specifically, the coarse ore pile 14 is located at the starting end of the entire loop as a storage place for the raw ore. The vibrating feeder 15 is arranged below the coarse ore pile 14, and its function is to feed the raw ore in the coarse ore pile 14 to the feeding belt conveyor 6 at a certain rate. The feeding belt conveyor 6 is responsible for conveying the raw ore and the subsequent processed stubborn stones and other materials to the semi-autogenous mill 1, and is an important conveying link connecting the raw ore supply and the semi-autogenous mill 1. The semi-autogenous mill 1 is the core grinding equipment, which grinds the raw ore and stubborn stones fed into it. The discharge end of the semi-autogenous mill 1 is connected to a double-layer vibrating screen 16, which can screen the materials discharged from the semi-autogenous mill 1. The screened material is stubborn stones, and the screened material enters other subsequent processes (such as possible further processing links such as pump pools). The stubborn stone return belt conveyor 7 is located between the double-layer vibrating screen 16 and the stubborn stone buffer bin 4, which is used to receive the stubborn stones screened from the double-layer vibrating screen 16 and transport it to the stubborn stone buffer bin 4. The stone buffer bin 4 is located above the stone processing section, and is used to buffer the stone screened from the double-layer vibrating screen 16, which plays a role in buffering material flow and stabilizing feeding. The first belt feeder 21 in the stone crushing system 2 transports the stone in the stone buffer bin 4 to the stone crusher 22, and the stone crusher 22 crushes the stone. The crushed stone is transported to the feeding belt conveyor 6 via the stone transfer belt conveyor 8, and finally returns to the semi-autogenous mill 1 for grinding again. The second belt feeder 31 of the stone bypass system 3 can directly transport the stone in the stone buffer bin 4 to the feeding belt conveyor 6 through the stone transfer belt conveyor 8 without crushing, and then send it to the semi-autogenous mill 1. This bypass design can flexibly adjust the stone processing path under different working conditions to achieve stable control of the total feeding amount of the circuit. The automatic ball adding machine 9 provides grinding media (steel balls, etc.) for the semi-autogenous mill 1 to ensure the effective implementation of the grinding process.

[0055] Furthermore, the material level meter 5 is installed on the stubborn stone buffer bin 4. The material level meter 5 can be on the top, side or inside of the stubborn stone buffer bin 4 (such as using different types of material level meters 5 such as non-contact or insertion type), which is used to monitor the material level height (L) of the stubborn stone in the buffer bin in real time. It should be noted that by monitoring the material level height, key information is provided for the control of the entire loop. When the stubborn stone material level is too high, it may mean that the stubborn stone production speed is greater than the stubborn stone processing (crushing or bypass transfer) speed. At this time, the working efficiency of the stubborn stone processing unit can be appropriately accelerated, such as increasing the processing capacity of the stubborn stone crusher 22 or increasing the transfer capacity of the stubborn stone bypass system 3; when the material level is too low, it may be necessary to check the stubborn stone screening of the front double-layer vibrating screen 16 or the working state of the semi-autogenous mill 1 to see whether the amount of stubborn stone production is reduced due to changes in the grinding effect. At the same time, the data of the material level meter 5 can also be used to prevent abnormal situations such as buffer overflow or empty bin, and ensure that the stubborn stone can be stably supplied to the subsequent processing links.

[0056] Further, the first electronic belt scale is located before the drop point of the feeding belt conveyor 6 relative to the stubborn stone transport belt conveyor 8, and the second electronic belt scale is located after the drop point. This means that the raw ore is first weighed by the first electronic belt scale, and then the stubborn stone (after crushing or bypass transfer) is added at the drop point, and then weighed by the second electronic belt scale. It should be noted that the first electronic belt scale is mainly used to measure the feed amount (W1) of the raw ore. This can help the operator understand the raw ore flow rate of the coarse ore pile 14 fed to the feeding belt conveyor 6 through the vibrating feeder 15. According to this data, the feeding speed of the vibrating feeder 15 can be adjusted to achieve a stable supply of raw ore. For example, if the first electronic belt scale shows that the raw ore feed amount is lower than the set value, the frequency of the vibrating feeder 15 can be appropriately increased to increase the raw ore supply. The second electronic belt scale is used to measure the total feed amount (W2) including the raw ore and the added stubborn stone. By comparing the data of the first electronic belt scale and the second electronic belt scale, the amount of stubborn stone added can be accurately known. Moreover, by monitoring the total feed rate, combined with the working requirements of the semi-autogenous mill 1 and the processing capacity of the entire circuit, the working states of the rock crushing system 2 and the rock bypass system 3 can be adjusted, thereby achieving stable control of the total feed rate of the circuit. For example, if the second electronic belt scale shows that the total feed rate is too high, it may be necessary to reduce the feed rate of the rock crusher 22 or reduce the transfer capacity of the rock bypass system 3.

[0057] Furthermore, the third electronic belt scale 12 is installed on the stone return belt conveyor, and the third electronic belt scale 12 is on the transportation path between the double-layer vibrating screen 16 and the stone buffer bin 4. It should be noted that the third electronic belt scale 12 is used to measure the stone flow rate (W3) returning from the double-layer vibrating screen 16 to the stone buffer bin 4. This data is very important for understanding the amount of stone produced. If the amount of stone returned displayed by the third electronic belt scale 12 suddenly increases, it may mean that the grinding effect of the semi-autogenous mill 1 has changed, resulting in an increase in the amount of stone screened, and it is necessary to further check the working parameters of the semi-autogenous mill 1 (such as grinding time, filling rate of grinding media, etc.); if the return amount decreases, it may be that the screening efficiency of the double-layer vibrating screen 16 has changed or the grinding effect of the semi-autogenous mill 1 has improved, resulting in a decrease in the amount of stone produced.

[0058] Furthermore, the fourth electronic belt scale 13 is installed on the stone transfer belt conveyor, and the fourth electronic belt scale 13 is on the transportation path of the stone from the stone buffer bin 4 to the feeding belt conveyor 6 after crushing (through the stone crushing system 2) or bypass (through the stone bypass system 3). It should be noted that the fourth electronic belt scale 13 is used to measure the stone flow rate (W4) ready to return to the semi-autogenous mill 1 after processing (crushing or bypass transfer). This data is critical for controlling the return amount of stone. According to the working requirements of the semi-autogenous mill 1 and the total feed control target of the entire circuit, the feeding speed of the first belt feeder 21 in the stone crushing system 2 or the transfer speed of the second belt feeder 31 in the stone bypass system 3 can be adjusted according to the data of the fourth electronic belt scale 13, so as to achieve precise control of the stone processing and return to the semi-autogenous mill 1. For example, if the total feed rate needs to be increased and the semi-autogenous mill 1 can handle more rock, the working efficiency of the rock crushing system 2 and / or the rock bypass system 3 can be appropriately increased according to the data of the fourth electronic belt scale 13.

[0059] In this embodiment, for medium hardness ores, the pebble crusher 22 selects a solution with lower processing capacity, and the processing capacity is determined according to the pebble yield of about 10%, and the discharge port gap is set to ≤15mm. Among them, the vibrating feeder 15, the semi-autogenous mill 1, the feeding belt conveyor 6, the first belt feeder 21, the second belt feeder 31 and the pebble transport belt conveyor 8 are all frequency conversion equipment, so that these equipment can flexibly change the operating parameters according to the actual production needs, and then more properly adapt to various working conditions, so as to achieve a stable and efficient operation state of the semi-autogenous mill-pebble crushing circuit.

[0060] The rock crushing process presents the following characteristics under normal working conditions: the first belt feeder 21 and the rock crusher 22 operate normally, while the second belt feeder 31 is in a shutdown state. The control method of the semi-autogenous grinding-rock crushing circuit provided in this embodiment has the following control logic:

[0061] Furthermore, when the grindability of the ore is stable, the rock crusher 22 operates normally without faults, and the rock processing capacity (W) of the rock crusher 22 is greater than or equal to the rock return capacity (W3) of the semi-autogenous grinding mill 1, the rock level (L) in the rock buffer bin continues to decrease. At this time, if the stone material level (L) in the stone buffer bin is higher than the low alarm value, the first belt feeder 21 and the stone crusher 22 are kept working normally, and the second belt feeder 31 is in a shutdown state, that is, the stone flow rate (W4) returned to the semi-autogenous mill 1 is kept stable, and the total feeding amount (W2=W1+W4) of the semi-autogenous mill 1 is kept stable; if the stone material level (L) in the stone buffer bin is lower than the low alarm value, the first belt feeder 21 and the stone crusher 22 are shut down, and the second belt feeder 31 is started at the same time to make the stones in the stone buffer bin directly sent to the stone transfer belt conveyor 8, and by adjusting the speed of the second belt feeder 31 (the frequency of the belt head motor), the stone transfer amount (W4) on the stone transfer belt conveyor 8 is kept consistent with the stone processing amount (W) of the stone crusher 22 (that is, W4=W). Since the stones in the second belt feeder 31 are not crushed by the stone crusher 22 and are directly sent to the stone transfer belt conveyor 8 The ore grindability of the belt conveyor 8 is reduced, and the return amount (W3) of the semi-autogenous mill 1 will increase. When the return amount (W3) of the semi-autogenous mill 1 is greater than the design index of the rock processing capacity (W) of the rock crusher 22, the rock transfer amount (W4) is slowly reduced to less than the return amount (W3) of the semi-autogenous mill 1. If W4=0.5W3 is maintained, the rock level (L) of the rock buffer bin will continue to rise. When the rock level (L) is higher than the high alarm value, the first belt feeder 21 and the rock crusher 22 are started, the second belt feeder 31 is stopped, and at the same time, steel balls are added by the automatic ball adding machine 9 to reduce the rock return amount (W3) of the semi-autogenous mill 1, so that the rock return amount of the semi-autogenous mill 1 and the rock processing amount (W) of the rock crusher 22 maintain a dynamic balance. At this time, the total feed amount of the semi-autogenous mill will smoothly transition from one stable state to another.

[0062] Furthermore, when the grindability of the ore is stable, the rock crusher 22 operates normally without faults, and the rock processing volume (W) of the rock crusher 22 is less than the rock return volume (W3) of the semi-autogenous grinding mill 1, the rock level (L) in the rock buffer bin continues to rise. At this time, if the rock material level (L) in the rock buffer bin is lower than the high alarm value, the rock crusher 22 is kept working normally, and the second belt feeder 31 is in a shutdown state, that is, the rock flow rate (W4) returned to the semi-autogenous mill 1 remains unchanged, and the total feeding amount (W2=W1+W4) of the semi-autogenous mill 1 remains stable. At the same time, steel balls are added by the automatic ball adding machine 9 to change the grinding efficiency of the semi-autogenous mill 1, and the rock return amount (W3) of the semi-autogenous mill 1 is reduced to maintain a dynamic balance with the rock processing amount (W) of the rock crusher 22; if the rock material level (L) in the rock buffer bin is higher than the high alarm value, the rock crusher 22 keeps working unchanged, and the second belt feeder 31 is started at the same time so that part of the rock in the rock buffer bin can be directly sent to the rock transfer belt conveyor 8, and the speed of the second belt feeder 31 (the belt head motor frequency) is adjusted to make the rock transfer belt conveyor 8 The rock flow rate (W4) returned to the SAG mill 1 in the belt conveyor 8 is kept in dynamic balance with the rock return amount (W3) discharged from the SAG mill 1. Since the rocks in the second belt feeder 31 are directly sent to the rock transfer belt conveyor 8 without being crushed by the rock crusher 22, the grindability of the ore is reduced. At this time, it is necessary to add steel balls through the automatic ball adding machine 9 to reduce the rock return amount (W3) discharged from the SAG mill 1. When the rock return amount (W3) discharged from the SAG mill 1 changes, the speed of the second belt feeder 31 (the belt head motor frequency) is adjusted to keep the rock flow rate (W4) returned to the SAG mill 1 in the rock transfer belt conveyor 8 and the rock return amount (W3) discharged from the SAG mill 1 in dynamic balance until they are consistent (i.e., W4=W3). At this time, the total feed amount of the SAG mill 1 will smoothly transition from one stable state to another.

[0063] Furthermore, when the grindability of the ore remains stable and the rock crusher 22 needs to be shut down for maintenance or malfunction, the second belt feeder 31 is started so that part of the rock in the rock buffer bin can be directly sent to the rock transfer belt conveyor 8. By adjusting the speed of the second belt feeder 31 (the belt head motor frequency), the rock flow rate (W4) of the rock transfer belt conveyor 8 returning to the semi-autogenous mill 1 and the rock return rate (W3) of the semi-autogenous mill 1 are kept in dynamic balance. Since the rock in the second belt feeder 31 is directly sent to the rock transfer belt conveyor 8 without being crushed by the rock crusher 22, the second belt feeder 31 can be directly fed to the rock transfer belt conveyor 8 without being crushed by the rock crusher 22. Conveyor 8, the grindability of the ore is reduced, at this time it is necessary to add steel balls through the automatic ball adding machine 9 to reduce the return amount of stubborn stones (W3) discharged from the semi-autogenous mill 1. When the return amount of stubborn stones (W3) discharged from the semi-autogenous mill 1 changes, adjust the speed of the second belt feeder 31 (the belt head motor frequency) to make the stubborn stone flow (W4) returning to the semi-autogenous mill 1 in the stubborn stone transfer belt conveyor 8 maintain a dynamic balance with the return amount of stubborn stones (W3) discharged from the semi-autogenous mill 1 until they remain consistent (i.e. W4=W3). At this time, the total feed amount of the semi-autogenous mill will smoothly transition from one stable state to another.

[0064] Further, when the grindability of the ore remains stable but the ore processing capacity of the semi-autogenous mill 1 needs to be changed. If the ore processing capacity of the semi-autogenous mill 1 needs to be reduced, firstly, the frequency of the vibrating feeder 15 is reduced to reduce its feeding capacity (W1), and at the same time, the second belt feeder 31 is started to directly send the stones in the stone buffer bin to the stone transfer belt conveyor 8, and by adjusting the speed of the second belt feeder 31 (the belt head motor frequency), the sum of the stone flow rate (W4) returning to the semi-autogenous mill 1 in the stone transfer belt conveyor 8 plus the feeding capacity (W1) of the vibrating feeder 15 is kept consistent with the total feeding capacity (W2). At this time, since the stones in the second belt feeder 31 are directly sent to the stone transfer belt conveyor 8 without being crushed by the stone crusher 22, the grindability of the ore is reduced, and the amount of stones returned (W3) discharged from the semi-autogenous mill 1 will increase, and it is necessary to add steel balls through the automatic ball adding machine 9 to reduce the amount of stones returned (W3) discharged from the semi-autogenous mill 1. Secondly, the speed of the second skin feeder (the frequency of the belt head motor) is slowly reduced until it stops, so that the sum of the rock flow (W4) returned to the SAG mill 1 in the rock transfer belt conveyor 8 after the speed reduction plus the rock feed amount (W1) of the vibrating feeder 15 is equal to the new ore processing volume to be executed. Finally, the speed of the SAG mill 1 (the motor frequency of the SAG mill 1) is slowly reduced, and the rock flow (W4) returned to the SAG mill 1 in the rock transfer belt conveyor 8 is kept in dynamic balance with the rock return amount (W3) of the SAG mill 1 discharge, and the total ore feed amount of the SAG mill 1 will smoothly transition from one stable state to another. If it is necessary to increase the ore processing volume of the SAG mill 1, first slowly increase the frequency of the vibrating feeder 15 and increase its ore feed amount (W1). At this time, the rock return amount (W3) of the SAG mill 1 discharge will increase, and it is necessary to add steel balls through the automatic ball adding machine 9 to reduce the rock return amount (W3) of the SAG mill 1 discharge. Secondly, the speed of the SAG mill 1 (the motor frequency of the SAG mill 1) is slowly increased to keep the return amount (W3) of the SAG mill 1 in the discharge of the SAG mill 1 consistent with the rock processing amount (W) of the rock crusher 22. Finally, when the sum of the rock flow (W4) returning to the SAG mill 1 in the rock transfer belt conveyor 8 plus the feed amount (W1) of the vibrating feeder 15 is equal to the new ore processing amount to be executed, the frequency of the vibrating feeder 15 and the frequency of the SAG mill 1 are kept stable. At this time, the total feed amount of the SAG mill 1 will smoothly transition from one stable state to another stable state.

[0065] Furthermore, when the grindability of the ore changes significantly within the first time (such as 30 minutes) and other equipment operates normally, the amount of rock returned (W3) discharged from the semi-autogenous mill 1 changes significantly. At this time, if the amount of rock returned (W3) discharged from the semi-autogenous mill 1 is significantly less than the rock processing capacity (W) of the rock crusher 22 within 30 minutes, the rock crusher 22 is shut down, and the second belt feeder 31 is started at the same time to send the rock in the rock buffer bin directly to the rock transfer belt conveyor 8. By adjusting the speed of the second belt feeder 31 (the frequency of the belt head motor), the rock flow rate (W4) of the rock returning to the semi-autogenous mill 1 in the rock transfer belt conveyor 8 is kept consistent with the rock processing capacity (W) of the rock crusher 22. Since the rock in the second belt feeder 31 is not crushed by the rock crusher 22 and is directly sent to the rock transfer belt conveyor 8, the rock in the second belt feeder 31 is not crushed by the rock crusher 22 and is directly sent to the rock transfer belt conveyor 8. The grindability of the ore on the belt conveyor 8 is reduced, and the return amount of stubborn stones (W3) discharged from the semi-autogenous mill 1 will become larger. At this time, it is necessary to add steel balls through the automatic ball adding machine 9 to reduce the return amount of stubborn stones (W3) discharged from the semi-autogenous mill 1. When the return amount of stubborn stones (W3) discharged from the semi-autogenous mill 1 changes, the speed of the second belt feeder 31 (the frequency of the belt head motor) is adjusted to keep the stubborn stone flow (W4) returned to the semi-autogenous mill 1 in the stubborn stone transport belt conveyor 8 and the return amount of stubborn stones (W3) discharged from the semi-autogenous mill 1 in a dynamic balance until they are consistent. At this time, the total feed amount of the semi-autogenous mill 1 will smoothly transition from one stable state to another. If the amount of rock returned from the SAG mill 1 (W3) is significantly greater than the amount of rock processed by the rock crusher 22 (W) within 30 minutes, the rock crusher 22 maintains its working state, and at the same time starts the second belt feeder 31 so that part of the rock in the rock buffer bin can be directly sent to the rock transfer belt conveyor 8. By adjusting the speed of the second belt feeder 31 (the frequency of the belt head motor), the rock flow rate (W4) of the rock returned to the SAG mill 1 in the rock transfer belt conveyor 8 is kept in dynamic balance with the amount of rock returned from the SAG mill 1 (W3). The crushed stone by the stone crusher 22 is directly sent to the stone transfer belt conveyor 8, and the grindability of the ore is reduced. At this time, it is necessary to add steel balls through the automatic ball adding machine 9 to reduce the return amount (W3) of the stone discharged from the semi-autogenous mill 1. When the return amount (W3) of the stone discharged from the semi-autogenous mill 1 changes, the speed of the second belt feeder 31 (the frequency of the belt head motor) is adjusted to keep the stone flow (W4) returning to the semi-autogenous mill 1 in the stone transfer belt conveyor 8 and the return amount (W3) of the stone discharged from the semi-autogenous mill 1 in a dynamic balance until they are consistent. At this time, the total feed amount of the semi-autogenous mill 1 will smoothly transition from one stable state to another.

[0066] The control method of the semi-autogenous grinding-rock crushing circuit provided in this embodiment can effectively cope with the changes in the material level of the rock buffer bin 4 by coordinating the control of the rock processing unit (including the rock crushing system 2 and the rock bypass system 3) and the semi-autogenous grinding mill 1. Specifically, when the rock level continues to drop and is higher than the low alarm value, the rock crushing system 2 is controlled to operate and the rock bypass system 3 is shut down. In this way, the processing path of the rock can be reasonably allocated according to the material level, avoiding the problem of rock amount fluctuation caused by the large selection of the rock crusher 22 in the prior art, and realizing the stable control of the total feed rate of the semi-autogenous grinding-rock crushing circuit; when the rock level continues to drop and is lower than the low alarm value, the rock crushing system 2 is controlled to shut down, the rock bypass system 3 is started, and the two are shut down. The transfer volume of the semi-autogenous mill 1 is matched with the transfer volume of the semi-autogenous mill 1, and combined with the monitoring and control of the return volume of the stubborn rock discharged from the semi-autogenous mill 1, it can ensure the reasonable treatment of the stubborn rock amount under the condition of low material level, and prevent the total feed volume from fluctuating greatly; when the stubborn rock material level is higher than the high alarm value or continues to rise, through the comprehensive control of the stubborn rock crushing system 2, the stubborn rock bypass system 3 and the semi-autogenous mill 1, such as adjusting the grinding efficiency, adjusting the stubborn rock transfer volume and other operations, the stubborn rock transfer volume and the stubborn rock return volume of the semi-autogenous mill 1 are kept in dynamic balance. This helps to maintain the stability of the semi-autogenous mill 1, avoids the problem of frequent fluctuations in the grinding process conditions caused by frequent and large fluctuations in the stubborn rock amount in the prior art, thereby ensuring the stable operation of the entire grinding process conditions; when the stubborn rock crushing system 2 is overhauled or shut down due to a fault, the stubborn rock bypass system can be controlled to start and adjust the operating state in time, and the grinding efficiency of the semi-autogenous mill 1 is adjusted at the same time, so that the stubborn rock transfer volume of the stubborn rock bypass system 3 and the stubborn rock return volume of the semi-autogenous mill 1 are kept in balance. In this way, when there is a problem with the equipment, the normal operation of the semi-autogenous mill-rock crushing circuit can still be guaranteed, reducing the impact of equipment failure on production; when adjusting the ore processing capacity of the semi-autogenous mill 1, through the sequential control of the feeding belt conveyor 6, the rock bypass system, the semi-autogenous mill 1 and other equipment, such as first adjusting the feeding frequency of the feeding belt conveyor 6, and then controlling the semi-autogenous mill 1 and the rock bypass system, the rock transfer capacity of the rock transfer belt conveyor 8 and the rock return capacity of the semi-autogenous mill 1 can be kept in dynamic balance. This makes the adjustment of the ore processing capacity more flexible, and the balance of the entire circuit can be maintained during the adjustment process, which improves the adaptability of the system to different production needs. In addition, by obtaining the rock return capacity of the semi-autogenous mill 1 and the ore processing capacity of the semi-autogenous mill 1, and performing corresponding control at different times according to the size relationship between the two, such as controlling the start and stop of the rock crushing system 2 and the rock bypass system and adjusting the working state, the rock transfer capacity and the ore processing capacity of the semi-autogenous mill 1 are kept balanced. This dynamic balance control method can effectively improve grinding efficiency, reduce energy and material consumption, and avoid the problem of low production efficiency caused by an imbalance between the amount of stubborn rock and the amount of ore processed.

[0067] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0068] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A control method for a semi-autogenous grinding-hard stone crushing circuit, characterized in that: The SAG mill-rock crushing circuit comprises a rock processing unit and a SAG mill, wherein the rock processing unit is capable of receiving rocks discharged from the SAG mill, the rock processing unit comprises a rock crushing system and a rock bypass system, wherein the rock crushing system is capable of crushing the rocks and then discharging them back to the SAG mill, and the rock bypass system is capable of discharging the rocks back to the SAG mill; The control method comprises: In response to the adjustment instruction, controlling the operating state of the stubborn stone processing unit; Controlling the semi-autogenous mill to adjust the grinding efficiency; Wherein, the SAG mill-rock crushing circuit further comprises a feeding belt conveyor and a rock transfer belt conveyor, wherein the rock transfer belt conveyor can receive and transfer the rock discharged from the rock crushing system and the rock bypass system to the feeding belt conveyor, and the feeding belt conveyor can transport the rock and raw ore to the SAG mill; The control method further comprises: Obtaining the ore processing capacity of the semi-autogenous mill; When the ore processing capacity of the SAG mill is reduced, the feeding belt conveyor is first controlled to adjust the feeding frequency, reduce the feeding capacity of the feeding belt conveyor, and control the start-up of the rock bypass system at the same time. Then, the SAG mill is controlled to adjust the grinding efficiency, reduce the amount of rock returned from the SAG mill, and then the rock bypass system is controlled to slow down until it stops. Finally, the SAG mill is controlled to slow down so that the rock transfer capacity of the rock transfer belt conveyor and the amount of rock returned from the SAG mill are kept in dynamic balance. Wherein, after obtaining the ore processing capacity of the semi-autogenous mill, the control method further comprises: When the ore processing capacity of the semi-autogenous mill is increased, the feeding belt conveyor is first controlled to adjust the feeding frequency and increase the feeding capacity of the feeding belt conveyor. At the same time, the semi-autogenous mill is controlled to adjust the grinding efficiency and reduce the amount of stubborn stones returned from the discharge of the semi-autogenous mill. Then, the semi-autogenous mill is controlled to speed up its operation. Finally, the feeding belt conveyor and the semi-autogenous mill are controlled to be stable in frequency.

2. The control method according to claim 1, characterized in that: The SAG mill-rock crushing circuit further includes a rock buffer bin, into which the rocks discharged from the SAG mill are discharged, and the rocks in the rock buffer bin are discharged to the rock crushing system and the rock bypass system; The control method further comprises: Obtaining the level of the hard stone in the hard stone buffer bin; When the rock material level continues to drop and is higher than the low level alarm value, the rock crushing system is controlled to operate, and the rock bypass system is controlled to shut down.

3. The control method according to claim 2, characterized in that: After obtaining the level of the hard stone in the hard stone buffer bin, the control method further includes: When the rock material level continues to drop and is lower than the low level alarm value, the rock crushing system is controlled to stop, and the rock bypass system is controlled to start, so that the rock transfer capacity of the rock bypass system is the same as the rock processing capacity of the rock crushing system; Obtaining the amount of stubborn rock returned from the SAG mill discharge; When the amount of rock returned from the SAG mill is greater than the amount of rock processed by the rock crushing system, the rock bypass system is controlled to slow down so that the amount of rock transported by the rock bypass system is less than the amount of rock returned from the SAG mill; Obtaining the level of the hard stone in the hard stone buffer bin; When the rock material level is higher than the high alarm value, the rock crushing system is controlled to start, the rock bypass system is controlled to shut down, and the semi-autogenous mill is controlled to adjust the grinding efficiency and reduce the amount of rock returned from the semi-autogenous mill, so that the amount of rock returned from the semi-autogenous mill and the rock processing capacity of the rock crushing system maintain a dynamic balance.

4. The control method according to claim 2, characterized in that: After obtaining the level of the hard stone in the hard stone buffer bin, the control method further includes: When the rock level continues to rise and is lower than the high alarm value, the rock crushing system is controlled to operate, the rock bypass system is controlled to shut down, and the semi-autogenous mill is controlled to adjust the grinding efficiency and reduce the amount of rock returned from the semi-autogenous mill, so that the amount of rock returned from the semi-autogenous mill and the rock processing capacity of the rock crushing system maintain a dynamic balance.

5. The control method according to claim 2, characterized in that: After obtaining the level of the hard stone in the hard stone buffer bin, the control method further includes: When the rock level continues to rise and is higher than the high alarm value, the rock crushing system is controlled to operate, the rock bypass system is controlled to start, and the rock bypass system is controlled to adjust its working state. At the same time, the semi-autogenous mill is controlled to adjust the grinding efficiency and reduce the amount of rock returned from the semi-autogenous mill, so that the sum of the rock transfer amounts of the rock crushing system and the rock bypass system maintains a dynamic balance with the amount of rock returned from the semi-autogenous mill.

6. The control method according to claim 1, characterized in that: The control method further comprises: When the rock crushing system is shut down for maintenance or failure, the rock bypass system is controlled to start and adjust its operating state, and the semi-autogenous mill is controlled to adjust its grinding efficiency to reduce the amount of rock returned from the semi-autogenous mill, so that the rock transfer volume of the rock bypass system and the amount of rock returned from the semi-autogenous mill are kept in dynamic balance.

7. The control method according to claim 1, characterized in that: The control method further comprises: Obtaining the amount of stubborn rock returned from the SAG mill and the ore processing capacity of the SAG mill; When the amount of rock returned from the semi-autogenous mill is less than the rock processing capacity of the rock crushing system within the first time, the rock crushing system is controlled to shut down, and the rock bypass system is controlled to start. At the same time, the semi-autogenous mill is controlled to adjust the grinding efficiency to reduce the amount of rock returned from the semi-autogenous mill, and the rock bypass system is controlled to adjust its working state, so that the sum of the rock transfer volumes of the rock crushing system and the rock bypass system maintains a dynamic balance with the ore processing capacity of the semi-autogenous mill.

8. The control method according to claim 7, characterized in that: After obtaining the amount of stubborn rock returned by the SAG mill and the ore processing amount of the SAG mill, the control method further includes: When the amount of rock returned from the semi-autogenous mill is greater than the rock processing capacity of the rock crushing system within the first time, the rock crushing system is controlled to operate, the rock bypass system is controlled to start, and the semi-autogenous mill is controlled to adjust the grinding efficiency to reduce the amount of rock returned from the semi-autogenous mill, and the rock bypass system is controlled to adjust its working state, so that the sum of the rock transfer volumes of the rock crushing system and the rock bypass system maintains a dynamic balance with the ore processing capacity of the semi-autogenous mill.

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