Highland concentrator grinding system heavy load linkage test load progression control and steel ball supplement method

Abstract

The application provides a highland ore-dressing plant grinding system heavy load linkage commissioning load progression control method, comprising the following steps: determining the altitude of the commissioning site; highland environment adaptation; setting four progressive load stages; commissioning operation; performing stage shutdown inspection operation; performing stage switching review; until all load stages are executed. Through the collaborative work of the three control links, the load progression control provides the main timing framework, the ball dynamic calculation provides the medium balance guarantee, and the highland parameter correction provides the environmental adaptability basis. The application realizes the systematic and quantitative control of the whole process of heavy load commissioning of a large grinding system.

Description

Technical Field

[0001] This invention relates to the field of industrial process control technology, and in particular to a method for load progression control and steel ball replenishment during heavy-load linkage commissioning of a grinding system in a high-altitude ore dressing plant. Background Technology

[0002] Before commencing formal production, a newly built large-scale mineral processing plant must conduct a heavy-load integrated commissioning of its grinding system after the completion of infrastructure construction. Grinding systems typically include semi-autogenous mills, ball mills, vertical stirred mills, and their associated hydrocyclone classification systems, feeding systems, and lubrication systems. The core purpose of the heavy-load integrated commissioning is to verify equipment performance and process reliability under loaded conditions, and to accumulate operating parameters for formal production. Essentially, the heavy-load integrated commissioning is a complex industrial process control system oriented towards multiple equipment, multiple stages, and multiple constraints. Its control objectives include safe equipment start-up and shutdown, smooth load transition, dynamic balance of grinding media, and continuous optimization of process parameters.

[0003] Currently, the following control methods are mainly used for heavy-load commissioning of grinding systems.

[0004] The first method is open-loop one-time load control. After commissioning, a rate of ore close to the design load is directly fed into the mill, allowing the system to reach its rated processing capacity in a short time. However, in the initial startup phase, the mill liners and steel balls have not yet been fully broken in, and the main bearing lubrication has not reached its optimal stable state. Directly subjecting the mill to full-load impact at this time can easily cause abnormal meshing of the large and small gears, a sudden rise in bearing temperature, motor overcurrent tripping, or even liner breakage. The fundamental flaw of this method is that it does not introduce load ramping constraints and ignores the load adaptability limitations of the equipment in the initial operation phase.

[0005] The second approach is experience-based step-by-step control. The commissioning process is roughly divided into two or three load stages, such as 50% load, 80% load, and 100% load, with each stage running for several days. However, the equipment operating parameters for each stage—including the amount of steel balls replenished, the number of hydrocyclones in operation, and the grinding concentration—are estimated by operators based on experience or directly applied using design values, lacking refined quantitative basis and a closed-loop feedback adjustment mechanism. Differences in experience among different operators lead to poor repeatability of commissioning results, making it difficult to develop standardized control procedures. The core problem with this approach is that control decisions rely on human experience rather than quantitative models, making it a typical example of open-loop experience-based control.

[0006] The third method is constant ball replenishment control. This involves determining the ball loading and replenishment amounts for each stage of the mill by referring to commissioning data from similar concentrators, or adopting a constant ball replenishment system—that is, adding one or two sizes of steel balls daily. However, the throughput and wear rate of steel balls differ at each stage. Using the same daily replenishment amount at low load stages as at high load stages inevitably leads to excessive ball replenishment at low loads, resulting in an accumulation of steel balls in the mill and an unnecessary increase in motor power consumption. Conversely, insufficient ball replenishment at high loads limits grinding capacity and results in substandard product fineness. The fundamental flaw of this method lies in the lack of a dynamic mathematical relationship between the replenishment amount and the state of the controlled object (cumulative throughput, wear rate). Ball replenishment control and load control are independent and lack coupling coordination.

[0007] Furthermore, none of the existing control methods mentioned above have specifically modified equipment parameters for high-altitude environments. At altitudes of 4500 to 5500 meters, air density is only about 60% of that at sea level, significantly reducing motor heat dissipation efficiency and lowering the breakdown strength of insulation by 8% to 13%. Simultaneously, the extreme diurnal temperature range in high-altitude regions, with average annual temperatures dropping below -20 degrees Celsius, leads to poor lubrication of lubricating oil at low temperatures and difficulties in equipment startup. Traditional commissioning methods directly utilize equipment parameters and protection thresholds from plains areas, resulting in frequent equipment failures such as overheating shutdowns, insulation breakdowns, and pipe freezing. The root cause lies in the failure to incorporate environmental parameters as pre-input parameters to the control system, resulting in insufficient environmental adaptability of the control system.

[0008] In summary, existing technologies suffer from systemic deficiencies in the following control aspects: First, load control lacks "ramp rate" constraints and state assessment decision gates, making it impossible to achieve smooth load progression; second, steel ball replenishment control lacks a dynamic model based on material balance, failing to adaptively adjust with load stages; and third, control parameters have not been systematically modified for high-altitude environments, resulting in insufficient robustness of the control system. These three issues are interconnected, collectively limiting the success rate and reproducibility of heavy-load commissioning of large-scale grinding systems in high-altitude environments. Summary of the Invention

[0009] This invention provides a method for progressive load control and steel ball replenishment during heavy-load commissioning of a grinding system in a high-altitude ore dressing plant, aiming to solve the technical problems existing in the aforementioned control methods. This invention divides the heavy-load commissioning control process into four load stages—30%, 60%, 90%, and 100%. Each stage is executed according to a preset processing capacity and runtime. A system-wide shutdown check and a Go / No-Go decision review gate are set between stages, forming a closed-loop progressive control logic of "setting-execution-detection-review-switching," allowing the equipment load to gradually approach the design value and eliminating the impact damage caused by a single loading. Regarding steel ball replenishment control, this invention establishes a dynamic calculation model based on "cumulative processing capacity of each stage × ball consumption per unit," quantitatively solving for the replenishment amount as a function of the cumulative processing capacity. This ensures that the replenishment control and load control form a coordinated coupling relationship, guaranteeing that the mill filling rate remains within the optimal range throughout the entire commissioning cycle. In terms of environmental adaptive control, this invention uses altitude and extreme temperature as feedforward inputs to establish a quantitative mapping rule from environmental parameters to control parameter correction coefficients. This includes a set of correction rules such as motor power correction coefficient, electrical clearance increase coefficient, creepage distance increase coefficient, and temperature protection threshold reduction range, enabling the control system to have high-altitude environment adaptive capabilities. Through the coordinated work of the above three control links—load progression control providing the main timing framework, ball replenishment dynamic calculation providing medium balance assurance, and high-altitude parameter correction providing the basis for environmental adaptability—this invention achieves systematic and quantitative control of the entire heavy-load commissioning process of a large-scale grinding system.

[0010] To achieve the above objectives, the present invention adopts the following technical solution: A method for load progression control during heavy-load commissioning of a grinding system in a high-altitude concentrator includes: determining the altitude of the commissioning site; adapting the grinding system to the high-altitude environment based on the determined altitude; after completing the high-altitude environment adaptation, setting the heavy-load commissioning process into four progressively increasing load stages according to the load percentage from low to high, with a load increment gradient of 30 percentage points between each load stage, and each load stage having a corresponding preset running time; executing the commissioning operation of each load stage sequentially from low to high according to the four load stages; after each load stage has run for the corresponding preset running time, performing an inter-stage shutdown check operation; after the inter-stage shutdown check operation is completed and passes acceptance, performing a stage switching review to determine whether the current load stage meets the switching conditions for entering the next load stage; when all switching conditions are met, allowing entry into the next load stage and continuing the commissioning operation until all load stages are completed.

[0011] A method for replenishing steel balls during heavy-load linkage commissioning of a grinding system in a high-altitude concentrator, used in a load progression control method for heavy-load linkage commissioning of a grinding system in a high-altitude concentrator, includes: obtaining the cumulative throughput of each grinding equipment at each load stage; determining the steel ball wear consumption per unit of each grinding equipment; multiplying the cumulative throughput at each stage by the corresponding steel ball wear consumption to obtain the total replenishment amount of the corresponding grinding equipment at the corresponding load stage; obtaining the mass ratio of each grade of ball diameter in the initial ball load of each grinding equipment; and distributing the total replenishment amount according to the mass ratio of each grade of ball diameter in the initial ball load to obtain the replenishment amount of each grade of ball diameter in the corresponding load stage of the corresponding grinding equipment.

[0012] In summary, the present invention has at least the following beneficial effects: This invention eliminates the impact damage to equipment caused by traditional one-time loading through a four-level progressive loading control strategy. Heavy-load testing starts from a low load, gradually transitioning to full load via intermediate loads, with each level having a set stable operating time, allowing the equipment load to increase smoothly at a preset ramp rate. The load increase gradient between levels is controlled within a reasonable range, avoiding mechanical and thermal shocks to the equipment caused by excessive load jumps. The mill system using this control method can operate continuously and stably for extended periods at full load, with the main bearing temperature consistently below the safe threshold.

[0013] This invention upgrades steel ball replenishment control from open-loop empirical estimation to closed-loop quantitative calculation through a quantitative calculation model based on "cumulative processing volume multiplied by ball consumption per unit consumption per stage". The replenishment amount in each stage is dynamically adjusted according to the cumulative processing volume, and the replenishment control and load control form a coordinated coupling relationship, avoiding the imbalance problem of excessive replenishment in the low-load stage and insufficient replenishment in the high-load stage. The deviation between the total cumulative replenishment amount in each stage and the theoretical calculation value can be controlled within a reasonable range, and the mill filling rate remains stable throughout the entire commissioning cycle.

[0014] This invention enhances the environmental adaptability of the control system through a complete set of equipment parameter correction methods for high-altitude environments. A quantitative mapping rule is established from altitude to correction coefficients and then to control parameter setpoints, including motor power correction coefficients, clearance increase coefficients, creepage distance increase coefficients, and temperature protection threshold reduction ranges. The corrected control parameters form a systematic deviation compensation with the original design values, ensuring that the control parameter setpoints match the actual operating conditions at high altitudes. After adopting the correction scheme of this invention, the robustness of the control system to environmental disturbances is significantly enhanced, and the number of unplanned shutdowns due to overheating or insulation failure is significantly reduced.

[0015] This invention employs a control strategy combining phased initial ball loading and dynamic ball replenishment to ensure the mill filling rate remains within its optimal range. The ball mill filling rate smoothly transitions from a low value through an intermediate value to the designed full-load value, avoiding the problems of excessive filling rate leading to "bloating" or excessively low filling rate resulting in insufficient grinding. During the full-load stage, both the semi-autogenous mill and the ball mill are within their respective optimal operating ranges, and both grinding efficiency and product fineness meet design expectations.

[0016] This invention establishes a complete database of the correspondence between "processing capacity - feed pressure - number of operating hydrocyclones" by combining quantitative calculation of the number of hydrocyclones in operation at each stage with pressure feedback adjustment. This database provides directly applicable control parameter settings for the formal production stage, avoiding the need for lengthy trial and error adjustments after commissioning and shortening the transition period from commissioning to formal production.

[0017] This invention constructs a closed-loop control method consisting of "control execution - status detection - problem diagnosis - decision review - next stage control" through inter-stage shutdown inspection and a Go / No-Go decision review mechanism. This mechanism ensures that all problems exposed in each stage are resolved before entering the next stage, preventing minor issues from being amplified into equipment damage failures under higher loads, and improving the success rate and safety of the commissioning process. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the load progression control and steel ball replenishment method for heavy-load linkage commissioning of a plateau ore dressing plant.

[0019] Figure 2 This is a schematic diagram of the filling rate variation curves at each stage. Detailed Implementation

[0020] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0021] like Figure 1 As shown, this embodiment provides a method for load progression control and steel ball replenishment during heavy-load linkage commissioning of a plateau ore dressing plant, including the following steps.

[0022] Step S1: Measure the environmental parameters at the test site. Environmental parameters must include at least altitude. Average annual minimum temperature and extreme minimum temperature .altitude Measurements were taken in meters, and temperature parameters were measured in degrees Celsius. Environmental parameters were measured before the start of the heavy-load linkage test run, and the results served as the basis for subsequent equipment parameter correction calculations. Altitude data was obtained using a calibrated barometric altimeter or GPS positioning device. The annual average minimum temperature and extreme minimum temperature were obtained by reviewing historical observation data from local meteorological stations over the past ten years.

[0023] Step S2, based on the altitude measured in step S1 The power selection of the main motor for the grinding system should be adjusted for high-altitude conditions. The high-altitude adjustment of the main motor should be performed as follows.

[0024] Set motor power correction factor . Calculate according to formula (1): ; in The altitude measured in step S1 is in meters. This is a dimensionless motor power correction factor. Formula (1) is applicable to altitudes... Operating conditions within the range of 1000 to 5500 meters. The physical meaning of formula (1) is: for every 1000 meters increase in altitude, the allowable output power of the motor decreases by approximately 10%, therefore the required power rating needs to be increased accordingly. For operating conditions at an altitude of 4500 meters, The calculated value is 1.538.

[0025] Actual power of the main motor Calculate according to formula (2): ;in The design power for plains areas is expressed in kilowatts. The motor power correction coefficient is defined by formula (1); The redundancy factor is a constant between 1.10 and 1.15. When the average temperature at the test site during the three winter months is below -10 degrees Celsius, it is taken as 1.15, and for other operating conditions, it is taken as 1.10. The actual power rating for high-altitude environments is given in kilowatts. The physical meaning of formula (2) is to add an extra 10% to 15% margin based on the power correction to cope with potential instantaneous overload and poor heat dissipation in high-altitude environments. In actual selection, Round up to the nearest whole number for the standard motor power rating. The insulation class of the main motor should be at least one level higher than the design requirements for plains areas. When the design insulation class for plains areas is F, H-class insulation should be used for high-altitude areas; when the design insulation class for plains areas is B, F-class insulation should be used for high-altitude areas. The temperature limit of H-class insulation is 180 degrees Celsius, and the temperature limit of F-class insulation is 155 degrees Celsius. Increasing the insulation class by one level increases the thermal margin by 25 degrees Celsius to compensate for the decrease in withstand voltage caused by the reduced strength of the insulation medium under the low air pressure environment of high altitudes.

[0026] Step S3, based on the altitude measured in step S1 The creepage distance and clearance of electrical equipment are corrected for high altitude. The creepage distance is corrected according to formula (3): ;in The standard creepage distance in a plain environment is expressed in millimeters. The elevation correction factor for the creepage distance is calculated according to formula (4); The corrected creepage distance is in millimeters.

[0027] ; in The altitude measured in step S1 is in meters. This is a dimensionless elevation correction factor for the creepage distance. Formula (4) is applicable to elevation... Operating conditions within the range of 2000 to 5500 meters. The physical meaning of formula (4) is: above 2000 meters altitude, the creepage distance increases by 10% for every 1000 meters increase in altitude. For operating conditions at an altitude of 4500 meters, The calculated value is 1.25.

[0028] The electrical clearance is corrected according to formula (5): ;in Standard electrical clearance in a plain environment, in millimeters; The elevation correction factor for electrical clearance is calculated according to formula (6); The corrected electrical clearance is in millimeters.

[0029] ; in The altitude measured in step S1 is in meters. This is a dimensionless electrical clearance altitude correction factor. Formula (6) is applicable to altitudes... Operating conditions within the range of 2000 to 5500 meters. The physical meaning of formula (6) is: above 2000 meters altitude, the electrical clearance increases by 5% for every 1000 meters increase in altitude. For operating conditions at an altitude of 4500 meters, The calculated value is 1.125.

[0030] When conductive dust is present at the test site, the correction factors for creepage distance and clearance should be multiplied by an additional 1.10 times based on the calculated values ​​above. Conductive dust refers to dust with a resistivity lower than... Dust concentrations of ohm-cm were confirmed using a dust resistivity tester. The presence of conductive dust further reduces the effective insulation distance of the insulating medium; therefore, dust environment correction is required in addition to altitude correction.

[0031] Corrected creepage distance and electrical clearance As the minimum insulation distance requirement when selecting electrical equipment, the equipment manufacturer shall meet the above parameter requirements during the equipment manufacturing stage, and the electrical professionals shall measure and confirm them on-site before the commissioning.

[0032] Step S4: Based on the environmental parameters measured in step S1, select appropriate cables and lubricating materials for high-altitude applications.

[0033] Cable selection should follow these steps: Select cold-resistant cables with an applicable temperature lower limit not exceeding -40 degrees Celsius. The cable's current-carrying capacity should be corrected using a high-altitude derating factor of 0.85 to 0.90. This means multiplying the rated current-carrying capacity in plains conditions by a factor of 0.85 to 0.90 to obtain the actual allowable current-carrying capacity in high-altitude environments. The physical reason for the current-carrying capacity derating is the thin air and reduced convective heat dissipation capacity at high altitudes, resulting in a higher cable temperature rise under the same current compared to plains environments.

[0034] When selecting a lubricating oil, perform the following steps: select one with a pour point lower than the extreme minimum temperature measured in step S1. The lubricating oil should have a pour point of at least 10 degrees Celsius. When the extreme minimum temperature is -21.1 degrees Celsius, the pour point of the lubricating oil should not exceed -31.1 degrees Celsius. The pour point represents the highest temperature at which the lubricating oil loses its fluidity; ensuring that the pour point is well below the extreme minimum temperature guarantees that the lubricating oil still has sufficient fluidity when the equipment is started at low temperatures.

[0035] For pipes, valves, and pumps installed outdoors, an insulation layer with a thickness of not less than 50 mm shall be laid. According to GB / T 8175 "Guidelines for Insulation Design of Equipment and Piping", in high-altitude and cold regions, the insulation layer thickness shall be calculated using the heat loss method, with 50 mm being the minimum thickness required to prevent the medium inside the pipeline from freezing within 4 hours of shutdown. All water accumulated inside unused equipment shall be completely drained after shutdown. Lubrication oil stations shall be equipped with electric heating devices with a heating power of not less than 2 kW.

[0036] Step S5, based on the altitude measured in step S1 The temperature protection thresholds for the equipment were adjusted for high-altitude conditions. The alarm value for motor winding temperature was lowered from the plain standard value of 130 degrees Celsius to 120 degrees Celsius. The alarm value for main bearing temperature was lowered from the plain standard value of 70 degrees Celsius to 65 degrees Celsius. The alarm value for gearbox oil temperature was lowered from the plain standard value of 60 degrees Celsius to 55 degrees Celsius. The reduction in temperature protection thresholds by 5 degrees Celsius is based on the following physical reason: the lower air density in high-altitude environments leads to a decrease in the convective heat transfer coefficient, resulting in a higher steady-state temperature rise for the equipment under the same heat output compared to low-altitude environments. Therefore, the alarm thresholds need to be lowered accordingly to provide the same safety margin at the same absolute temperature.

[0037] The results of the equipment parameter correction under the above-mentioned high-altitude environment are summarized in Table 1.

[0038] Table 1. Comparison Table of Equipment Parameter Correction for High-Altitude Areas ; Step S6: Confirm the start-up conditions for heavy-load linkage test run. Start-up conditions include: all main process equipment has passed individual unit test runs, the clean water linkage test run is completed with no pipeline leaks, the interlock protection system is functioning normally, all operators are in place, and sufficient production materials such as ore, water, electricity, and reagents are prepared. After all start-up conditions are met, proceed to step S7.

[0039] Step S7: Set the four-level progressive load parameters. Based on the single-series design processing capacity. Based on the standard, the unit is tons per day. Steps S2 to S5, which complete the parameter correction for the high-altitude equipment, are the preparatory steps before the trial start-up; steps S7 to S17 complete the main process of the trial load progressive control; steps S18 to S26 complete the calculation and execution of the steel ball replenishment quantity in parallel with the main process. The parameters for the four-level progressive load are executed according to Table 2.

[0040] Table 2. Parameter Table for Four-Level Progressive Load ; In Table 2, The design capacity for a single series is expressed in tons per day. , , , These represent the number of operating days for levels one through four, in days. , , , These figures represent the cumulative processing capacity for stages one through four, in tons. Hourly processing capacity is a theoretical calculation; actual feed rate is controlled based on this value, and equipment operating rate is assumed to be 100%. The load increment between each load stage is 30 percentage points. Setting 30% as the starting load is based on the following considerations: Before the equipment is fully broken in, a load below 30% will result in insufficient material filling in the mill to achieve effective grinding, making it impossible to verify the system's true operating status; while a starting load above 30% significantly increases the risk of impact.

[0041] Step S8: Perform the trial run at the first stage of 30% load. During the trial run at the first stage of 30% load, the semi-autogenous mill is not initially loaded with balls, and the filling rate is 0%. The technical consideration for not loading balls at the 30% load stage is that the semi-autogenous mill relies mainly on the impact of large ore pieces for initial crushing under extremely low loads; the presence of steel balls is not necessary at this time. Not loading balls avoids additional impact damage to the incompletely broken-in liners and also facilitates verification of the purely mechanical operation of the feeding, lubrication, and control systems without steel ball interference. The objectives of the first stage of 30% load are: to verify the operation of the feeding, lubrication, and control systems under low loads, to investigate pipeline leaks and abnormal vibrations, and to provide baseline data for subsequent ball-loading operations. The first stage of 30% load runs continuously for 5 days. During operation, the following parameters are recorded hourly: semi-autogenous mill main bearing temperature, ball mill main bearing temperature, motor current of each mill, feed rate, discharge particle size, and hydrocyclone feed pressure. The recorded data is taken as the sliding average of the last 24 hours at the end of each stage, which serves as the judgment benchmark value for condition three in step S10 - the operating parameters are within the allowable range, and also serves as the data basis for the compilation of formal production operation procedures.

[0042] Step S9: After 5 days of operation at the first-level 30% load stage, perform an inter-stage shutdown inspection. The inter-stage shutdown inspection includes: shutting down the entire system, including at least the semi-autogenous mill, ball mill, belt conveyor, vibrating feeder, and flotation machine; organizing technical personnel from mechanical, electrical, process, and automation disciplines to conduct a comprehensive inspection of all equipment; the inspection should include at least the equipment bearing temperature, gear meshing status, liner bolt tightness, pipeline leaks, and the tightness of electrical terminals; summarizing the problems found during the inspection in the commissioning problem log; classifying and rectifying all problems in the log, and after rectification, a joint acceptance inspection by the construction unit, construction unit, supervision unit, and equipment supplier. The core function of setting up inter-stage shutdown inspections is to centrally resolve problems exposed in each stage before entering the next load stage, preventing minor problems from evolving into equipment damage failures under subsequent higher loads. Initial ball loading is carried out simultaneously with the shutdown inspection and is completed during the shutdown inspection period without adding extra downtime.

[0043] Step S10: After the four-party joint acceptance in Step S9 is passed, a Go / No-Go review for phase transition is performed. The conditions for passing the Go / No-Go review include the following four conditions: Condition 1: No equipment damage incidents occurred during the current phase of equipment operation; Condition 2: All problems exposed in the current phase have been resolved and passed the four-party joint acceptance; Condition 3: All equipment operating parameters at the end of the current phase are within the allowable range, including at least the main bearing temperature not exceeding 65 degrees Celsius, the motor current not exceeding the rated value, and the lubricating oil temperature not exceeding 55 degrees Celsius; Condition 4: The operators have passed the operational skills assessment under the current load. The assessment method is a practical assessment. Operators must independently complete at least one shift of operation within the last 24 hours of continuous operation in the current load phase, without any violations, and all equipment operating parameters must be qualified to pass the assessment. The motor current is determined using the sliding average value of the last 24 hours of the phase. An instantaneous peak not exceeding 110% of the rated value and lasting no more than 3 seconds is not considered an overshoot. When all four conditions are met, the review result is a Go decision, allowing entry into the next load phase. If any one of the above four conditions is not met, the review result is a No-Go decision, and the rectification and improvement work will continue in the current stage until all four conditions are met.

[0044] Step S11: After the review result in step S10 is a Go decision, the second-level 60% load stage trial operation is performed. Upon entering the second-level 60% load stage, the initial ball charge of the semi-autogenous mill is introduced all at once during the shutdown inspection. This ensures the semi-autogenous mill's filling rate reaches over 4%, with the initial ball gradation ratio following the semi-autogenous mill's design full-load gradation. During the second-stage 60% load phase, the semi-autogenous mill's ball replenishment is performed daily on average, following the methods described in steps S18 to S21. The ball mill operates synchronously at the ball load corresponding to the second-stage 60% load phase, with the ball load for each load phase calculated and determined according to the method described in step S22. The grinding and classification system begins to form a closed-loop cycle. The second-stage 60% load phase operates continuously for 5 days. The daily throughput of the second-stage 60% load phase is set as follows: At the end of the second-stage 60% load phase, the cumulative processing volume of the second-stage phase... ,in day.

[0045] Step S12: After running for 5 days in the second-level 60% load phase, repeat the inter-phase shutdown check operation described in step S9 and the Go / No-Go review described in step S10. After passing the review, proceed to the third-level 90% load phase.

[0046] Step S13: Perform the commissioning operation for the third-level 90% load phase. The daily processing capacity for the third-level 90% load phase is set as follows: The third stage, operating at 90% load, lasts for 10 consecutive days. Upon entering the third stage at 90% load, the semi-autogenous mill is initially charged with balls during a one-time shutdown inspection. This ensures that the semi-autogenous mill filling rate reaches over 8%. At the end of the third stage at 90% load, the cumulative throughput of the third stage... ,in day.

[0047] During the third-stage 90% load operation, the number of hydrocyclones in operation, grinding concentration, and classification pressure are finely adjusted. The method for determining the number of hydrocyclones in operation involves the following steps: setting the target control range for the hydrocyclone feed pressure to 0.06 MPa to 0.10 MPa. The design processing capacity of a single hydrocyclone is... The unit is tons per hour. The theoretical number of hydrocyclones in operation at a given load stage. Calculate according to formula (7): ; in This represents the hourly processing capacity for this load phase, expressed in tons per hour. The design processing capacity of a single hydrocyclone is expressed in tons per hour. The calculated number of hydrocyclones is the theoretical number of units to be activated, rounded up. The specific number of units activated for different types of hydrocyclones at each load stage is shown in Table 3.

[0048] Table 3. Correspondence between the number of hydrocyclones in operation and the load. ; Actual number of units activated The adjustment is determined according to the principle of "symmetrical start-stop," that is, with two units as the minimum adjustment unit for adding or removing units. When When it is an odd number, Pick To ensure symmetry.

[0049] The adjustment rules for the number of hydrocyclones in operation are shown in Table 4.

[0050] Table 4. Pressure Regulation Rules ; One additional unit is added when the feed pressure is between 0.10 MPa and 0.12 MPa; two additional units are added when the feed pressure is greater than 0.12 MPa.

[0051] During operation, the feed pressure of the hydrocyclone is monitored in real time. Columnar sediment refers to sediment flowing out in a continuous columnar shape with a relatively high solid-liquid ratio; umbrella-shaped sediment refers to sediment spreading out in a uniform umbrella shape with a moderate solid-liquid ratio; loose sediment refers to sediment in a loose granular form with a relatively low solid-liquid ratio. When the pressure is greater than 0.10 MPa and the sediment is columnar, increase the number of operating units by 1 or 2. When When the pressure is less than 0.06 MPa and the sediment is loose, reduce the number of operating units by 1 or 2. When When the pressure is between 0.06 MPa and 0.10 MPa and the sediment is umbrella-shaped, the current number of operating units remains unchanged.

[0052] Step S14: After running for 10 days in the third-level 90% load phase, repeat the inter-phase shutdown check operation described in step S9 and the Go / No-Go review described in step S10. After passing the review, proceed to the fourth-level 100% load phase.

[0053] Step S15: Perform the commissioning operation for the fourth-level 100% load phase. The daily processing capacity for the fourth-level 100% load phase is set as follows: The fourth stage, operating at 100% load, lasts for 15 consecutive days. Upon entering the fourth stage, at 100% load, the remaining initial charge of the semi-autogenous mill is added in one go during a shutdown inspection. This allows the semi-autogenous mill to achieve its designed full-load filling rate. That is, 12%, corresponding to the total initial ball load. The unit is tons. At the end of the fourth stage (100% load), the cumulative processing volume of the fourth stage is... ,in The ball mill has reached its designed full-load ball loading capacity. The corresponding ball mill design full-load filling rate It is 30%.

[0054] Step S16: During the 15-day continuous operation at 100% load in the fourth stage, each shift is 8 hours long. The following parameters are recorded for each shift: feed rate to each mill, discharge particle size distribution, motor power, motor current, main bearing temperature, lubricating oil temperature, hydrocyclone feed pressure, and hydrocyclone overflow particle size. An alarm is triggered when the following abnormalities occur: main bearing temperature exceeds 65 degrees Celsius, motor current exceeds 105% of the rated value, hydrocyclone feed pressure exceeds the range of 0.06 MPa to 0.10 MPa, and lubricating oil temperature exceeds 55 degrees Celsius.

[0055] Step S17: After 15 days of operation at the fourth-level 100% load stage, a comprehensive evaluation of the trial run results is conducted. The passing criteria for the comprehensive evaluation are: no major equipment failures and all process indicators reaching more than 90% of the design values. After passing the comprehensive evaluation, the heavy-load linkage trial run is completed.

[0056] Step S18: Determine the steel ball wear consumption per unit of grinding equipment. The steel ball wear consumption is determined by either a laboratory small-scale mill wear test or by referring to production statistics from concentrators producing similar ore. "Similar ore" refers to ore whose absolute relative deviations from the target ore in Protodyakonov's hardness coefficient and Bond's index do not exceed 10%. Reference data should be obtained from production statistics from at least three similar concentrators or from a cumulative operating period of at least 30 days, with the average value from each data source used as the basis for the value. The specific operation of the laboratory small-scale mill wear test is as follows: Using a standard Bond's index mill with a diameter of 305 mm × 305 mm, a rotation speed of 70 rpm, and a grinding concentration of 65% to 75%, a predetermined amount of representative ore and steel balls are loaded into the laboratory mill. After running under the set grinding conditions to the predetermined grinding fineness, the mass loss of the steel balls is measured, and the steel ball wear amount corresponding to the unit ore throughput is calculated.

[0057] The specific wear loss of steel balls in a semi-autogenous grinding mill is denoted as: The unit is kilograms per ton of ore. The wear consumption of steel balls in a ball mill is denoted as... The unit is kilograms per ton of ore. The wear consumption of steel balls in a vertical stirred mill is denoted as... The unit is kilograms per ton of ore.

[0058] Step S19: Calculate the total amount of balls supplied to each mill at each load stage according to formula (8): ;in This is the index number for the load phase. These correspond to four load stages: 30%, 60%, 90%, and 100%, respectively. This is the index number for the mill type. Represents a semi-autogenous mill. Represents a ball mill. Represents a vertical stirred mill; For the first Cumulative throughput during the load phase, in tons. The values ​​are obtained from Table 2; For the first The wear consumption of steel balls in a mill is expressed in kilograms per ton of ore. For the first The mill in the first The total amount of balls replenished during the load phase, in kilograms.

[0059] The physical meaning of formula (8) is that the wear of steel balls in the mill is directly proportional to the total amount of ore processed, and the proportionality coefficient is the steel ball wear consumption per unit. The total amount of replenished balls is equal to the cumulative processing volume of each stage multiplied by the steel ball wear consumption per unit.

[0060] Step S20: According to formula (9), the total amount of replacement balls calculated in step S19 is... Distribute according to the initial packing ratio of each ball diameter: ;in For the ball diameter level index number, , For the first The total number of ball diameter grades for each type of mill; For the first The first type of mill The mass ratio of the bulb diameter in the initial bulb load is a dimensionless percentage and satisfies the following conditions: ; For the first The mill in the first During the load phase The amount of replacement balls for each ball diameter is expressed in kilograms. The physical meaning of formula (9) is: the amount of replacement balls for each ball diameter is distributed according to the proportion of that grade in the initial ball load, so as to keep the particle size composition of the ball load in the mill consistent with the design gradation.

[0061] Step S21: Perform the staged ball loading and replenishment operation for the semi-autogenous mill. The total initial ball load at full load for the semi-autogenous mill is denoted as... The unit is tons. The design full-load filling rate of a semi-autogenous mill. The initial ball charge of the semi-autogenous mill is 12%. Effective volume of semi-autogenous mill Steel ball bulk density Design filling rate porosity between steel balls According to the formula Confirmed, among which In cubic meters The unit is tons per cubic meter. This refers to the bulk density of steel balls, expressed in tons per cubic meter (t / m³), with a typical range of 4.80 to 4.95 t / m³. The bulk density of forged steel balls is typically 4.85 to 4.95 t / m³, while that of cast steel balls is typically 4.80 to 4.90 t / m³. Actual measurements are required for the most accurate and specific values. The porosity between steel balls is a dimensionless percentage, ranging from 0.38 to 0.45. This is used in the initial gradation of a semi-autogenous mill. millimeters millimeters millimeters millimeters The mass ratio of the five ball diameters is 20%, 31%, 22%, 18%, and 9%. This gradation is the recommended gradation for a semi-autogenous mill operating at full load. In practical applications, it can be adjusted within ±5 percentage points according to ore hardness, mill specifications, and product fineness requirements, but the sum of the proportions of each ball diameter must remain at 100% after adjustment. The porosity of the steel ball pack corresponding to the above gradation ratio is... The measured value was 0.42. If measured data is unavailable for engineering calculations, a typical value within the range of 0.38 to 0.45 can be used based on the steel ball gradation. However, different gradation ratios correspond to different values. The values ​​differ; it is recommended to determine them through a stacking test. The initial ball loading of the semi-autogenous mill adopts a staged loading strategy: the initial loading amount for the first stage at 30% load is... tons; the second-level 60% load phase input is The input amount for the third-level 90% load stage is: The input amount for the fourth level 100% load phase is: Initial ball loading was completed during shutdown inspections to avoid dynamic impact.

[0062] During the first stage at 30% load, the total ball replenishment volume of the semi-autogenous mill No ball replacement operation will be performed.

[0063] During the second stage at 60% load, the total amount of ball replenishment for the semi-autogenous mill is calculated according to formula (10): ;in This refers to the cumulative processing capacity during the second stage at 60% load, expressed in tons. The wear consumption of steel balls in a semi-autogenous grinding mill is expressed in kilograms per ton of ore. This refers to the total amount of feed balls required for the semi-autogenous mill during the second stage at 60% load, expressed in kilograms. After converting to tons, During the operation period, the amount of balls replenished is distributed on a daily average basis. The unit is tons per day. The total ball input of the semi-autogenous mill during the second stage at 60% load. (Convert to tons).

[0064] During the third stage at 90% load, the total amount of ball replenishment for the semi-autogenous mill is calculated according to formula (11): ;in This refers to the cumulative processing volume at the third-level 90% load stage, in tons. The wear consumption of steel balls in a semi-autogenous grinding mill is expressed in kilograms per ton of ore. This represents the total amount of balls added during the third stage (90% load) of the semi-autogenous mill, expressed in kilograms. After converting to tons, During the operation period, the amount of balls replenished is distributed on a daily average basis. Total ball input of the semi-autogenous mill at 90% load in the third stage. .

[0065] In the fourth stage, at 100% load, the initial ball loading volume was: It is put into operation all at once during the shutdown inspection when entering the fourth level. The total number of balls replenished during operation is calculated according to formula (12): ;in This represents the cumulative processing capacity at the fourth stage of 100% load, expressed in tons. The wear consumption of steel balls in a semi-autogenous grinding mill is expressed in kilograms per ton of ore. This represents the total amount of ball replenishment required for the semi-autogenous mill during the fourth stage at 100% load, expressed in kilograms. After converting to tons, During the operation period, the amount of balls replenished is distributed on a daily average basis. Total ball input of the semi-autogenous mill at 100% load in the fourth stage. .

[0066] Step S22 involves performing the staged initial ball loading and replenishment operations for the ball mill. The total initial ball load at full load for the ball mill is denoted as... The unit is tons. The design full-load filling rate of the ball mill. The initial ball load of the ball mill is 30%. The effective volume of the ball mill Steel ball bulk density Design filling rate porosity between steel balls According to the formula Confirmed. Among them... The porosity between the steel balls is a dimensionless percentage, ranging from 0.38 to 0.45. Its specific value depends on the steel ball gradation and the semi-autogenous mill in step S21. The value is determined using the same method. The porosity between steel balls in the ball mill. The initial gradation of the ball mill is determined by actual measurement. The method for determining it is the same as that for the semi-autogenous mill in step S21, but the values ​​may vary depending on the gradation. The actual measured values ​​shall prevail.

[0067] The target ball quantity in the ball mill at the end of each load stage is set as follows: At the end of the first stage (30% load), the ball quantity in the ball mill is... The corresponding filling rate is 9%; at the end of the second stage of 60% load, the ball volume in the ball mill is The corresponding filling rate was 18%; at the end of the third stage (90% load), the ball volume in the ball mill was... The corresponding filling rate was 27%; at the end of the fourth stage of 100% load, the ball volume in the ball mill was... The corresponding filling rate is 30%.

[0068] The initial ball charge of the ball mill adopts a phased charging strategy to gradually approach the target ball quantity within the mill. The initial ball charge quantity during the first stage at 30% load is... The initial ball loading volume at the second stage (60% load) is... The initial ball loading volume at the third stage (90% load) is... The initial ball loading volume at the fourth stage (100% load) is... The initial ball loading was completed during the shutdown inspection to avoid dynamic impact. The technical consideration for adopting this step-by-step loading strategy of 30% in the first three stages and 10% in the fourth stage is that if the total amount of initial balls is loaded all at once, the mill's starting torque will be too large, which may cause motor overload or impact damage to the mechanical transmission system; the step-by-step loading allows the filling rate to smoothly transition from 9% to 18%, 27% to 30%, with the increase in filling rate at each step controlled within 10 percentage points, ensuring a smooth transition in the mill's operating state.

[0069] The total amount of balls replenished during the operation of the ball mill at each load stage is calculated according to formula (13): ;in This is the index number for the load phase. ; For the first Cumulative throughput during the load phase, in tons; The wear consumption of steel balls in a ball mill is expressed in kilograms per ton of ore. For the ball mill in the first The total amount of replenished balls during the load phase, in kilograms. Its function is to compensate for the first The mass of steel balls lost due to grinding during the load stage is used to maintain the target ball quantity in the mill at the end of the stage.

[0070] ball mill in the first Mill ball volume during load phase Calculate recursively according to formula (14): ;in This indicates that there were no balls in the mill before the trial run; the unit is tons. The number of balls in the mill at the end of the previous load stage, in tons; For the first The initial ball loading volume during the load phase, in tons; For the first The total amount of ball replenishment during the load phase is in tons, calculated by formula (13) and then converted to tons; For the first The actual wear of the steel balls during the load-bearing phase, expressed in tons, in actual operation... (Ignoring measurement error), therefore formula (14) can be simplified to This means the number of balls inside the mill is approximately equal to the cumulative initial ball load. Theoretical target value. ( )and Through this recursive control, the ball mill filling rate was gradually increased in increments of 9%, 18%, 27%, and 30%.

[0071] when When the deviation between the theoretical calculation value and the estimated filling rate value derived from the motor current exceeds 10%, the initial ball loading amount for the next stage shall be corrected according to the following formula: ,in This is the value derived from the motor current. The calculated value is from formula (14). The theoretical calculated value of the ball quantity inside the mill. As an internal reference value of the central control DCS system, it is cross-validated with the filling rate estimate obtained by back-derived from the motor current in step S25.

[0072] Step S23: Perform the calculation of the distribution of ball replenishment amount for each ball diameter stage of the ball mill. The initial loading distribution of the ball mill... The mass ratio of bulb diameter is , , This represents the total number of ball diameter classes in the ball mill. In a typical initial load configuration of a ball mill, the mass proportion of Φ80 mm ball diameter is approximately 75%, and the mass proportion of Φ60 mm ball diameter is approximately 25%.

[0073] ball mill in the first Load Phase The initial loading amount of bulbs is calculated according to formula (15): ;in For the ball mill in the first The total initial ball load during the load phase, in tons; For the first The mass ratio of bulb diameter in the initial gradation is a dimensionless percentage. For the ball mill in the first Load Phase The initial loading quantity of seed bulbs is in tons.

[0074] ball mill in the first Load Phase The amount of replacement bulbs for the diameter of the seed bulb is calculated according to formula (16): ;in For the ball mill in the first Total ball replenishment volume during the load phase, in tons; For the first The mass ratio of bulb diameter in the initial gradation is a dimensionless percentage. For the ball mill in the first Load Phase The amount of bulbs replenished during the planting process, measured in tons.

[0075] ball mill in the first Load Phase The total number of balls thrown according to the diameter of the seed ball is calculated according to formula (17): ;in Calculated using formula (15), the unit is tons; Calculated using formula (16), the unit is tons; For the ball mill in the first Load Phase The total number of balls thrown, measured in tons.

[0076] Step S24: Perform daily ball replenishment. Daily ball replenishment is performed on a shift basis, with each shift lasting 8 hours.

[0077] The daily ball supply for a mill during a certain load stage is calculated according to formula (18): ; in This refers to the total amount of balls added to the mill during this load phase, in tons. This refers to the number of operating days during this load phase, in days. This refers to the daily ball replenishment volume, expressed in tons per day.

[0078] The theoretical number of balls to be added for each shift is calculated according to formula (19): ; in The daily ball replenishment amount is calculated using formula (18), in tons per day; The theoretical ball replenishment volume for each shift, in tons per shift.

[0079] In practice, the amount of pellets added per shift is rounded up to the nearest whole ton. The theoretical pellet addition amount for each shift... If it is not an integer, take the value less than 1. The largest integer value is used as the actual amount added; any balance less than 1 ton is carried over to the next shift. The carryover balance at the end of each phase is included in the total actual pelleting amount for that phase and does not roll over to the next phase. The theoretical pelleting amount for the next shift is... The sum of the carry-over balance from the previous shift is rounded down again and added, with the remaining balance carried over. Through this balance carry-over mechanism, the cumulative error for each shift is controlled within the range of -0.99 tons to +0.99 tons. After a finite number of shifts, the proportion of the cumulative error to the total theoretical replenishment volume approaches zero, avoiding the accumulation of systematic deviations caused by shift-by-shift rounding. When the accumulated rounding error in a certain stage exceeds 1 ton, this error is deducted in the replenishment plan for the next stage. The above balance carry-over mechanism and the end-of-stage deviation correction mechanism address errors of different natures. The balance carry-over process handles the small remainders generated by shift-by-shift rounding, which are usually less than 1 ton and are included in the actual replenishment volume for this stage. The end-of-stage deviation correction process handles systematic deviations caused by non-rounding factors such as fluctuations in ore properties and changes in equipment status. This deviation is independent of the shift rounding error, and correction is triggered only when the deviation exceeds 5% of the total theoretical replenishment volume for this stage.

[0080] The calibration relationship between the ball replenishment amount and the motor power is obtained as follows: Under stable operating conditions, record the no-load power respectively. and full load power This linear calibration relationship applies to fill rates between 5% and 35%; recalibration is required for fill rates outside this range. (Additional ball quantity) With power The relationship is based on the linear interpolation formula Confirmed, among which To design full-load ball loading capacity, This is the current measured power. and All units are kilowatts. Before each ball replenishment operation, record the current motor power and motor current of the mill. After each ball replenishment operation, observe the change in motor power. When the increase in motor power exceeds 20% of the expected increase, suspend the ball replenishment operation and analyze the cause. The expected increase is determined based on the calibration relationship between the ball replenishment amount and motor power described in the preceding part of step S24.

[0081] After each phase, the percentage deviation between the actual total ball replenishment volume of that phase and the theoretical total ball replenishment volume calculated by formula (8) or formula (13) is calculated. The cutoff point for deviation statistics is when the last ball replenishment operation of that load phase is completed. Ball replenishment operations during inter-phase shutdown checks are not included in the statistics of the previous phase. When the deviation percentage exceeds 5%, the ball replenishment volume is adjusted in the ball replenishment plan of the next phase. Let... This refers to the theoretical total number of balls to be replenished during this stage, calculated using formula (8) or formula (13). This represents the total number of balls actually replenished during this stage, as recorded by the ball replenishment metering device. Correction factor. Calculate according to formula (20): ; in This represents the theoretical total ball replenishment amount for this stage, in tons. This refers to the total amount of balls actually replenished during this phase, in tons. This is a dimensionless correction factor. When the actual ball replacement amount is greater than the theoretical ball replacement amount, If the actual number of balls added is less than 1, the number of balls added in the next stage will be reduced; when the actual number of balls added is less than the theoretical number of balls added... If the actual ball replenishment amount is greater than 1, the ball replenishment amount will be increased in the next stage. When the deviation between the actual ball replenishment amount and the theoretical ball replenishment amount at the end of the stage exceeds 5%, the deviation will be equally distributed to each day of the next stage—that is, the daily ball replenishment amount in the next stage. Increase or decrease the deviation based on , This represents the number of operating days for the next phase. If the deviation occurs at the fourth level (100% load), the deviation will not be allocated to subsequent phases but will be recorded in the comprehensive commissioning evaluation as an input parameter for the ball replenishment system correction in the formal production phase.

[0082] Step S25: Perform dynamic monitoring and adjustment of the mill filling rate. The mill filling rate is defined as the percentage of the volume occupied by the steel balls inside the mill to the effective volume of the mill.

[0083] Figure 2 The target filling rate curves for the semi-autogenous mill and ball mill at the end of four load stages are shown. The target filling rate of the ball mill at the end of each load stage is set as follows: at the end of the first stage (30% load), the ball mill filling rate is 9%; at the end of the second stage (60% load), the ball mill filling rate is 18%; at the end of the third stage (90% load), the ball mill filling rate is 27%; and at the end of the fourth stage (100% load), the ball mill filling rate is 30%.

[0084] The target filling rate of the semi-autogenous mill at the end of each load stage is set as follows: at the end of the first stage with a 30% load, the filling rate of the semi-autogenous mill is 0%; at the end of the second stage with a 60% load, the filling rate of the semi-autogenous mill is 4%; at the end of the third stage with a 90% load, the filling rate of the semi-autogenous mill is 8%; and at the end of the fourth stage with a 100% load, the filling rate of the semi-autogenous mill is 12%.

[0085] During operation, if the mill motor current is below 80% of the rated value, it is considered that the filling rate is too low, and the amount of balls added in the next shift will be increased. The method for increasing the amount of balls added is to multiply the theoretical amount of balls added in the next shift by 1.10. If the mill motor current is above 105% of the rated value, it is considered that the filling rate may be too high, and the ball adding operation will be suspended while checking for excessive accumulation of steel balls inside the mill. The checking method includes comparing the current motor power with historical power data under the same processing capacity. The historical power data is the average power of the same period on the second day after the current load stage has stabilized, to ensure that the ore properties and processing capacity conditions are basically the same. If the current power is more than 10% higher than the historical power, excessive accumulation of steel balls is confirmed, and the subsequent ball adding amount will be reduced until the power returns to the normal range.

[0086] Step S26: Perform the ball loading and replenishment operation for the vertical stirred mill. The material processed by the vertical stirred mill is the fine-grained product after the ball mill discharge. The impact load on its grinding media is much smaller than that of a semi-autogenous mill and a ball mill. Therefore, the initial ball loading will not cause impact damage to the equipment. The initial ball loading of the vertical stirred mill is performed all at once when it enters the first stage of 30% load. The total initial ball loading capacity of the vertical stirred mill at full load is [not specified in the original text]. Effective volume of vertical stirred mill Steel ball bulk density Design filling rate porosity between steel balls According to the formula It is confirmed that the definition and value method of each parameter are consistent with those in step S21.

[0087] The ball replenishment amount for a vertical stirred mill is calculated according to formula (21): ;in This is the index number for the load phase. ; For the first Cumulative throughput during the load phase, in tons; The wear consumption of steel balls in a vertical stirred mill is expressed in kilograms per ton of ore. For vertical stirred mills in the first The total amount of ball replenishment during the load phase is in kilograms. The ball replenishment amount for the vertical stirred mill is added in tons, rounded up. Any balance less than 1 ton is carried over to the next shift, consistent with the balance carryover mechanism in step S24.

[0088] Step S27: Automatic recording and control of ball replenishment quantity is performed through the ball replenishment metering device. The ball replenishment metering device is installed at the ball replenishment port of the mill. The ball replenishment metering device includes a weighing sensor and a counting device. The accuracy of the weighing sensor is ±50 kg. The counting device automatically records the type, quantity, and total weight of each ball replenishment. The data from the ball replenishment metering device is uploaded to the central control DCS system in real time. When the cumulative ball replenishment quantity of a shift reaches the theoretical ball replenishment quantity calculated by formula (19), the ball replenishment metering device issues an audible and visual prompt signal, indicating "Ball replenishment quantity has reached the standard".

[0089] Step S28 involves closed-loop verification of the ball replenishment effect using a real-time motor power monitoring system. Each mill's main motor is equipped with a power transmitter. The power transmitter connects the power signal to the central control DCS system. The central control DCS system displays the motor power, motor current, and historical trend curves in real time. When the motor power exceeds 105% of the rated value, the central control DCS system automatically issues an alarm signal, prompting the operator to check the filling rate; when the motor power is below 80% of the rated value, the central control DCS system automatically issues a warning signal, prompting the operator to increase the ball replenishment frequency according to the method described in step S25.

[0090] Step S29: Automatic adjustment of the number of hydrocyclones in operation is performed through the hydrocyclone pressure monitoring system. Pressure transmitters are installed on the feed pipes of each hydrocyclone group. The pressure transmitter readings are accurate to 0.01 MPa. The signals from the pressure transmitters are connected to the central control DCS system. The central control DCS system displays the feed pressure of each hydrocyclone group in real time. The criteria for determining the sediment morphology—the definitions of columnar sediment, umbrella-shaped sediment, and loose sediment—are performed according to the definitions in step S13.

[0091] When the feed pressure exceeds the target range of 0.06 MPa to 0.10 MPa, the central control DCS system automatically displays an operation prompt stating, "Please adjust the number of hydrocyclones in operation." The operator manually adjusts the number of hydrocyclones in operation according to the prompt and the adjustment rules described in step S13. After adjustment, the operator continues to monitor the feed pressure until it returns to the target range.

[0092] Step S30: Automatic control of lubricating oil temperature is performed through the lubricating oil temperature monitoring system. PT100 resistance temperature sensors are installed on the mill main bearing and gearbox. The PT100 resistance temperature sensors monitor the lubricating oil temperature in real time. The temperature signal is connected to the central control DCS system.

[0093] When the lubricating oil temperature is below 10 degrees Celsius, the central control DCS system automatically activates the electric heating device of the lubricating oil station. The electric heating device preheats the lubricating oil to a temperature between 20 and 25 degrees Celsius. Before the lubricating oil temperature reaches above 20 degrees Celsius, the mill starting circuit is locked, prohibiting the mill from starting. When the lubricating oil temperature exceeds 55 degrees Celsius, the central control DCS system automatically issues an alarm signal. When the lubricating oil temperature exceeds 60 degrees Celsius, the central control DCS system automatically triggers the mill shutdown protection.

[0094] Step S31: Input and generate reports for ball replenishment data via local operation terminals. Each ball replenishment point is equipped with a local operation terminal, which includes a touchscreen and an industrial PDA. Operators input the type, quantity, and batch number of each ball replenishment via the local operation terminal. The local operation terminal then uploads the input data to the central control DCS system.

[0095] The central control DCS system automatically generates a ball replenishment execution report based on the uploaded data. The report includes at least the following: ball replenishment quantity for each ball type, cumulative ball replenishment quantity, percentage deviation from theoretical values, and an estimated current mill filling rate. Management personnel can query the ball replenishment execution report in real time via local operating terminals or the central control screen.

[0096] Step S32 involves data interaction and collaborative control between the central control DCS system and each monitoring device. Weighing data from the ball replenishment metering device, power data from the real-time motor power monitoring system, pressure data from the hydrocyclone pressure monitoring system, and temperature data from the lubricating oil temperature monitoring system are all aggregated by the PLC controller. The PLC controller then uploads the aggregated data to the central control DCS system server via industrial Ethernet.

[0097] The central control DCS system automatically generates the theoretical ball replenishment quantity for each load stage and shift according to the calculation model of formulas (8) to (21). The central control DCS system compares the theoretical ball replenishment quantity with the actual ball replenishment quantity uploaded by the ball replenishment metering device in real time. When the deviation between the actual ball replenishment quantity and the theoretical ball replenishment quantity exceeds 5%, the central control DCS system triggers an alarm and pushes the comparison result to the industrial PDA used by the management personnel.

[0098] The central control DCS system compares the power data uploaded by the real-time motor power monitoring system with the theoretical power data calculated based on the current filling rate. When the deviation between the actual power and the theoretical power exceeds ±10%, the central control DCS system automatically adjusts the theoretical ball replenishment amount for subsequent shifts. The adjustment method is to multiply the theoretical ball replenishment amount for subsequent shifts by a power deviation correction factor. , Calculate according to formula (22): ; in The theoretical power is calculated based on the current filling rate, and the unit is kilowatts; The actual power uploaded by the motor power real-time monitoring system, in kilowatts; This is a dimensionless power deviation correction factor. When the actual power is higher than the theoretical power, If the value is less than 1, reduce the amount of replacement balls; when the actual power is lower than the theoretical power, If the value is greater than 1, increase the number of replacement balls.

[0099] The central control DCS system compares the pressure data uploaded by the hydrocyclone pressure monitoring system with the target range of 0.06 MPa to 0.10 MPa. When the pressure exceeds the target range for more than 30 minutes, the central control DCS system automatically calculates the recommended adjustment value for the number of hydrocyclones to be opened and pushes the recommended value to the operator's terminal.

[0100] The present invention has the following technical effects compared with the prior art.

[0101] The four-stage progressive loading strategy eliminates the impact damage to the equipment caused by traditional one-time feeding. Heavy-load commissioning starts at 30% load, gradually transitioning to 60%, 90%, and finally 100% load, with each stage having a set number of stable operating days, allowing the mill to gradually adapt to high loads from low loads. The load increase gradient between stages is 30 percentage points, avoiding mechanical and thermal shocks caused by excessive load jumps. In engineering applications, mill systems using this method can operate stably and continuously for 15 days at 100% load, with the main bearing temperature consistently not exceeding 62 degrees Celsius, far below the manufacturer's alarm threshold of 70 degrees Celsius.

[0102] By employing a quantitative calculation formula based on "cumulative processing volume per stage multiplied by ball consumption per unit," steel ball replenishment has been upgraded from empirical estimation to precise calculation. The replenishment amount at each stage is dynamically adjusted according to the processing volume, avoiding the imbalance of excessive replenishment at low load stages and insufficient replenishment at high load stages. The deviation between the total cumulative replenishment amount at each stage and the theoretical calculation value can be controlled within 5%.

[0103] A complete set of equipment parameter correction methods for high-altitude environments ensures reliable equipment operation under high-altitude conditions. Quantitative conversion rules were established from altitude to correction factors and then to equipment parameters, including motor power correction factors, clearance increase factors, creepage distance increase factors, and temperature protection threshold reduction ranges. After adopting the correction scheme of this invention, the number of equipment overheating shutdowns decreased from an average of 5 to 8 times per month using traditional methods to zero times.

[0104] By combining phased initial ball loading with dynamic ball replenishment, the mill filling rate is consistently maintained within the optimal range. The ball mill filling rate smoothly transitions from 9% to 18%, 27%, and finally 30%, avoiding the problems of excessive filling rate leading to "bloating" or insufficient grinding due to excessive filling rate. At 100% load, the semi-autogenous mill filling rate is 12%, and the ball mill filling rate is 30%, both within their respective optimal operating ranges.

[0105] The actual verification of the number of hydrocyclones started at each stage has formed a complete database of the correspondence between "processing capacity - feed pressure - number of start-ups", providing a direct operational basis for formal production and avoiding the problem of having to explore and debug for a long time after the trial run.

[0106] By implementing inter-phase shutdown checks and a Go / No-Go review mechanism, we ensured that all problems exposed in each phase were resolved before moving to the next phase, thus preventing small problems from accumulating into major failures.

[0107] Example 1: This example uses a large copper mine beneficiation plant in Tibet as an example. The beneficiation plant is located in a plateau region at an altitude of 4500 meters, with a single-series design processing capacity of... The daily processing capacity is 37,500 tons. The grinding system includes one semi-autogenous mill, two ball mills, and two vertical stirred mills. The semi-autogenous mill and ball mills form independent grinding loops, and the steel balls are not moved between equipment.

[0108] Perform step S1 to measure the environmental parameters at the test site. The altitude was measured using a calibrated barometric altimeter. Meters, by consulting historical observation data from local meteorological stations over the past ten years, the average annual minimum temperature was obtained. Celsius, extreme minimum temperature Celsius.

[0109] Perform step S2 to perform a high-altitude correction on the selected power of the main motor of the grinding system. Calculate the motor power correction coefficient according to formula (1): ; Calculate the actual power of the main motor according to formula (2). The design power of a certain feeder belt motor is taken as an example. Taking kilowatts as an example, since the average temperature on site is below -10 degrees Celsius for the three months of winter, we take... : The standard motor specifications are rounded up to 75 kW. The motor insulation class is upgraded from F to H.

[0110] Perform step S3 to perform altitude correction on the creepage distance and clearance of the electrical equipment. Calculate the creepage distance altitude correction factor according to formula (4): ; The creepage distance correction factor is 1.25. The clearance elevation correction factor is calculated according to formula (6): ; The electrical clearance correction factor is 1.125. The resistivity of the copper concentrate dust at the site, as measured by a dust resistivity tester, is [value missing]. Ohm-cm, below The ohm-cm value indicates a conductive dust environment. Therefore, the creepage distance correction factor is multiplied by 1.10, resulting in an actual creepage distance correction factor of [value missing]. The clearance correction factor is multiplied by an additional 1.10, resulting in an actual clearance correction factor of [value missing]. .

[0111] Perform step S4 to select appropriate cables and lubricating materials for high-altitude applications. Select cold-resistant cables with a minimum operating temperature of -40°C. Adjust the cable current-carrying capacity according to a high-altitude derating factor of 0.88. Select low-temperature lubricating oil with a pour point of -35°C. Install a 60mm thick insulation layer on exposed pipelines. Install a 3kW electric heating unit at the lubrication station.

[0112] Perform step S5 to perform high-altitude correction on the equipment temperature protection thresholds. Set the motor winding temperature alarm value to 120 degrees Celsius. Set the main bearing temperature alarm value to 65 degrees Celsius. Set the gearbox oil temperature alarm value to 55 degrees Celsius.

[0113] Execute step S6 to confirm the start-up conditions for the heavy-load linkage test. All main process equipment has passed the individual unit test, the clean water linkage test has been completed and there are no leaks in the pipelines, the interlock protection system is functioning normally, all personnel are in place, and there are sufficient supplies of ore, water, electricity, and reagents.

[0114] Execute step S7 to set the four-level progressive load parameters. Single-series design processing capacity. Tons per day. The parameters for the four-level progressive load are as follows: Level 1, 30% load: Daily processing capacity 11,250 tons, hourly processing capacity 468.75 tons, operation... Daily, cumulative processing volume in each phase ton.

[0115] Level 2, 60% load: Daily processing capacity 22,500 tons, hourly processing capacity 937.50 tons, operation... Daily, cumulative processing volume in each phase ton.

[0116] Level 3, 90% load: Daily processing capacity 33,750 tons, hourly processing capacity 1,406.25 tons, operation... Daily, cumulative processing volume in each phase ton.

[0117] Level 4, 100% load: Daily processing capacity 37,500 tons, hourly processing capacity 1,562.50 tons, operation... Daily, cumulative processing volume in each phase ton.

[0118] The four phases operated for a total of 35 days, with a total cumulative processing volume of 1,068,750 tons.

[0119] Execute step S8 to perform the first-stage 30% load trial run. The semi-autogenous mill is not initially loaded with balls; the filling rate is 0%. The system operates continuously for 5 days at a daily throughput of 11,250 tons. During operation, the main bearing temperature, motor current, feed rate, discharge particle size, and hydrocyclone feed pressure are recorded hourly.

[0120] Step S9 was executed. After 5 days of operation at the first-level 30% load stage, an inter-stage shutdown inspection was performed. The entire system was shut down, and technical personnel from the mechanical, electrical, process, and automation disciplines conducted a comprehensive inspection. The inspection revealed 3 minor pipeline leaks and 2 loose electrical connections, all of which were recorded in the commissioning problem log and rectified. The system passed joint acceptance by the construction unit, the contractor, the supervision unit, and the equipment supplier.

[0121] Execute step S10, and conduct a Go / No-Go review for the phase transition. All four conditions are met: no equipment damage incidents have occurred; all issues have been resolved and passed four-party acceptance; the main bearing temperature is 58 degrees Celsius, the motor current is 78% of the rated value (24-hour sliding average at the end of the phase), and the lubricating oil temperature is 42 degrees Celsius, all within the allowable range; the operators have passed the operational skills assessment under the current load and independently completed two shifts of operation in the last 24 hours, with all equipment operating parameters meeting the requirements. The review result is a Go decision, allowing entry into the second-level 60% load phase.

[0122] Execute step S11 to perform the second-stage 60% load trial run. Upon entering the second stage, the semi-autogenous mill's initial ball charge is introduced all at once during the shutdown inspection. The total design full-load initial ball charge of the semi-autogenous mill in this embodiment is known. tons, then Tons, rounded to 103 tons. The calculated filling rate is... The ball mill achieved a ball loading rate of over 4%. The system operated synchronously with phased ball loading. The system operated continuously for 5 days at a daily processing capacity of 22,500 tons.

[0123] Perform steps S18 to S21 to calculate the ball replenishment amount for the semi-autogenous grinding mill. The ball wear consumption of the semi-autogenous grinding mill was determined using a laboratory Bond work index mill after 30 minutes of operation at a grinding concentration of 70% and a rotation speed of 70 rpm. kilograms per ton of ore.

[0124] Cumulative processing volume at the second-level 60% load stage Tons. Calculate the total number of replacement balls according to formula (10): Rounded to 56 tons. Distributed evenly over 5 days, the daily replenishment volume is: Tons per day. The initial gradation of the semi-autogenous mill is... millimeters millimeters millimeters millimeters Five ball diameters (millimeters) are available, with mass ratios of 20%, 31%, 22%, 18%, and 9%. The replenishment amount for each level is allocated according to formula (9): 11 tons of millimeter-sized balls were added. 18 tons for millimeter-long ball replacement. 12 tons for millimeter-long ball replacement. 10 tons of millimeter-sized balls were added. 5 tons of millimeter-sized balls were used for ball replacement.

[0125] Perform steps S22 and S23 to calculate the initial ball loading and replenishment amounts for the ball mill. The total initial ball loading amount at full load for the ball mill in this embodiment is known. Tons. Specific consumption of steel balls worn in a ball mill. The weight per kilogram per ton of ore is determined by production statistics from similar ore beneficiation plants.

[0126] Initial ball loading was carried out during the first stage of 30% load. Tons. Operating replenishment volume. kilogram The weight is 34 tons, rounded down. At the end of the first stage, the number of balls in the mill is approximately 207 tons (the 34 tons of replenished balls exactly compensate for the 34 tons of wear in this stage), corresponding to a filling rate of... The target value has been achieved.

[0127] The second stage, at 60% load, involves the initial loading of the balls. Tons. Operating replenishment volume. kilogram The number of balls in the mill at the end of the second stage is approximately 414 tons (rounded up to 68 tons). The 68 tons of replacement balls compensated for the 68 tons of wear in this stage, corresponding to a filling rate of 68%. The target value has been achieved.

[0128] The initial ball loading was carried out during the third stage at 90% load. Tons. Operating replenishment volume. kilogram The weight is rounded up to 203 tons. At the end of the third stage, the total number of balls in the mill is approximately 621 tons (the initial cumulative ball load). The 203 tons of replacement balls compensated for the 203 tons of wear in this stage, corresponding to a filling rate of [missing information]. The target value has been achieved.

[0129] The initial ball loading was introduced during the fourth stage, 100% load phase. Tons. Operating replenishment volume. kilogram The weight was rounded up to 338 tons. At the end of the fourth stage, the number of balls in the mill was approximately 690 tons (the initial cumulative ball load). The 338 tons of replenished balls compensated for the 338 tons of wear in this stage, corresponding to a filling rate of 30%, reaching the designed full load value.

[0130] Regarding the initial ball loading input for the semi-autogenous grinding mill, the second stage input is 103 tons, and the third stage input is 103 tons. Rounded down to 103), the fourth-level input was 87 tons. The rounding is 88, but considering the rounding deviations of the first two levels, the actual fourth level is rounded to 87 tons to make the cumulative total 293 tons. The cumulative total is 293 tons. All the above rounding deviations are automatically eliminated in subsequent operations through the balance carry-over and end-of-stage correction mechanisms described in step S24.

[0131] Perform steps S12 to S14 to sequentially complete the commissioning operations for the second-level 60% load stage, the third-level 90% load stage, and the fourth-level 100% load stage. A shutdown inspection and Go / No-Go review are performed after each stage. During the third-level 90% load stage, the measured hydrocyclone feed pressure was 0.075 MPa to 0.092 MPa, within the target range of 0.06 MPa to 0.10 MPa. The sediment was umbrella-shaped, indicating good classification. During the fourth-level 100% load stage, which lasted for 15 consecutive days, the main bearing temperature peaked at 62 degrees Celsius, below the alarm threshold of 65 degrees Celsius; the motor current peaked at 98% of the rated value, below the alarm threshold of 105%.

[0132] Execute step S24 to perform the daily ball replenishment operation. Taking the ball mill at 100% load in the fourth stage as an example, the total ball replenishment volume is... tons, number of operating days Daily ball replenishment amount is calculated according to formula (18): ; The theoretical ball replenishment amount for each shift is calculated according to formula (19): ; In practice, each shift adds an integer 7 tons of pellets, with 0.51 tons carried over to the next shift. The theoretical pellet replenishment amount for the next shift is... The amount of pellets added is rounded down to 8 tons, with a remaining balance of 0.02 tons carried forward. This balance carry-forward mechanism ensures that the long-term average replenishment amount does not deviate from the design value.

[0133] Steps S27 to S32 are executed, through the monitoring devices and the central control DCS system, to automatically record, verify, and coordinate the ball replenishment quantity. The weighing data, motor power monitoring data, hydrocyclone pressure data, and oil temperature monitoring data of the ball replenishment metering device are all aggregated by the PLC controller and uploaded to the central control DCS system via industrial Ethernet. The central control DCS system compares the actual ball replenishment quantity with the theoretical ball replenishment quantity in real time, and the deviation is controlled within 5%. When the motor power deviates from the theoretical value, the central control DCS system automatically calculates the power deviation correction coefficient according to formula (22) and adjusts the subsequent ball replenishment quantity.

[0134] A comprehensive evaluation was conducted after the heavy-load joint commissioning. The mill system operated stably and continuously for 15 days at 100% load without any major equipment failures. All process parameters reached over 92% of the design values. The commissioning was successfully completed.

[0135] In some embodiments, after the Go / No-Go stage switching review in step S10 is passed, the following load progression rate adaptive adjustment operation is also performed before entering the next load stage.

[0136] Step S1001: After the phase switch Go / No-Go review is approved, obtain the following operating parameters for the last full shift (8 hours) before the end of the current load phase: main bearing temperature sequence. Motor current sequence Hydrocyclone feed pressure sequence Mill vibration acceleration sequence And the actual cumulative processing volume during the current load phase. Phase-based cumulative processing volume Temperature sequence The unit is Celsius, current sequence The unit is ampere, pressure series The unit is megapascal (MPa), vibration acceleration sequence The unit is meters per second squared, and the time interval between each sequence is 1 second. These data are derived from the historical operation data recorded in steps S8 and S16.

[0137] Step S1002: Calculate the load adaptability index for the current load phase according to formula (23). : ; in The main bearing temperature sequence for the current shift The average value, in degrees Celsius, is calculated according to formula (24): ; The total number of sampling points in the sequence. For the first Each sampling time; The main bearing temperature sequence for the current shift The standard deviation, in degrees Celsius, is calculated according to formula (25): ; Motor current sequence The range, in amperes, is calculated according to formula (26): ; The maximum allowable range of motor current is taken as 10% of the motor's rated current, and the unit is amperes. Cyclone feed pressure sequence The range, in megapascals, is calculated according to formula (27): ; The maximum allowable range of the hydrocyclone feed pressure is set to 0.04 MPa, which is the upper and lower limit difference of the target control range of 0.06 MPa to 0.10 MPa set in step S13. The current shift's mill vibration acceleration sequence The average value, in meters per second squared, is calculated according to formula (28): ; The current shift's mill vibration acceleration sequence The standard deviation, in meters per second squared, is calculated according to formula (29): ; The load fitness index is a dimensionless index, ranging from 0 to 1. The closer it is to 1, the more stable the equipment is operating under the current load and the more suitable it is for entering the next higher load phase; The closer it is to 0, the greater the fluctuation in equipment operation during the current load phase, and the longer the adaptation time required.

[0138] Step S1003: Calculate the unit's overall health index after the current load phase ends according to formula (30). : ; in The bearing temperature health index is calculated according to formula (31): ; It is a dimensionless exponent with a value range of 0 to 1, where 55 degrees Celsius is the upper limit of the optimal operating range of bearing temperature, and 65 degrees Celsius is the main bearing temperature alarm threshold set in step S5. The motor current health index is calculated according to formula (32): ; in For the current shift's motor current sequence The average value, in amperes; This is the rated current of the motor, measured in amperes. It is a dimensionless exponent with a value range of 0 to 1, where 0.80 times the rated current is the upper limit of the optimal operating range of the motor current, and 1.0 times the rated current is the motor current alarm threshold set in step S10. The hydrocyclone feed pressure health index is calculated according to formula (33): ; in The current shift's hydrocyclone feed pressure sequence The average value is expressed in megapascals (MPA). It is a dimensionless exponent, with a value range of 0 to 1, where 0.07 MPa to 0.09 MPa is the optimal operating range for feed pressure, and 0.06 MPa to 0.10 MPa is the allowable range set in step S13; The vibration health index is calculated according to formula (34): ; in The upper limit of the mill vibration acceleration under good operating conditions is set at 2.0 m / s². The alarm threshold for mill vibration acceleration is set to 5.0 meters per second squared. This is a dimensionless index, ranging from 0 to 1. The thresholds for the above health indices (55 degrees Celsius, 0.80 times the rated current, 0.07~0.09 MPa, 2.0 m / s²) are recommended values ​​by the equipment manufacturer. In actual applications, they can be adjusted within ±10% depending on the specific equipment model and operating conditions.

[0139] Step S1004: Based on the load fitness index calculated in step S1002 The unit's overall health index calculated in step S1003 The load acceleration factor for the next load stage is calculated according to formula (35). : ; in It is a dimensionless load acceleration factor, with a value ranging from 0 to 0.5. The physical meaning is: when the equipment is running smoothly ( High) and good overall health ( (High) A value approaching 0.5 indicates that the evaluation time for this stage needs to be appropriately increased to confirm operational stability; when equipment operation fluctuates significantly or its health deteriorates, A value close to 0 indicates that the preset runtime should remain unchanged.

[0140] Step S1005, based on the load acceleration factor The actual number of operating days for the next load phase is calculated according to formula (36). : ; in The number of preset operating days for the next load phase is set in Table 1 in step S7, in days; The load acceleration factor defined by formula (35); This represents the actual number of operating days for the next load phase, in days. When the actual number of operating days exceeds the preset number, the equipment needs more time to adapt to the increased load; when At that time, the actual number of operating days is equal to the preset number of days.

[0141] Step S1006: Calculate the actual number of operating days for the next load phase according to formula (36). Adjust the stage cumulative processing capacity setting value for the next load stage according to formula (37). : ; in The cumulative processing volume for the next load stage is set in Table 1 in step S7, in tons; The number of preset operating days for the next load phase is set in Table 1 in step S7, in days; The actual number of operating days for the next load phase, calculated using formula (36), is in days. This is the set value for the cumulative processing volume of the next load phase after adjustment, in tons.

[0142] Step S1007: Adjust the actual number of operating days for the next load phase. and stage cumulative processing volume setting value Feedback is sent to step S7 to replace the preset number of operating days and the cumulative processing volume setting value for the corresponding load stage in Table 1; at the same time, the adjusted parameters are output to steps S11, S13 or S15 (depending on the current load stage) to update the daily processing volume control target for the corresponding load stage. The updated daily processing volume is calculated according to formula (38): ; in This is the adjusted daily processing capacity for the next load phase, expressed in tons per day. This value replaces the corresponding daily processing capacity setting in steps S11, S13, or S15.

[0143] The aforementioned adaptive adjustment of the load progression rate, by introducing a feedback loop based on actual operating data, ensures that the progression rate of the load phase is no longer fixed but dynamically adjusted according to the actual operational stability and health status of the equipment at the current load phase. This forms a complete control loop of "execution → evaluation → feedback → adjustment." When the equipment is operating smoothly, the adaptation time is automatically reduced; when the equipment's operation fluctuates, the adaptation time is automatically extended, achieving responsive adjustment of the load progression control to the actual state of the equipment.

[0144] Example 2: Based on Example 1, Example 2 further optimizes the method for determining the number of hydrocyclones to be turned on.

[0145] In this embodiment, the design processing capacity of a single coarse grinding hydrocyclone is... Tons per hour. Hourly throughput at each load stage. The rates are as follows: Level 1: 468.75 tons per hour; Level 2: 937.50 tons per hour; Level 3: 1406.25 tons per hour; Level 4: 1562.50 tons per hour.

[0146] Calculate the theoretical number of coarse grinding hydrocyclones to be in operation at each load stage according to formula (7): Level 1 30% load: Rounded up to 4 units. Following the principle of symmetrical start-stop, 4 units were actually activated.

[0147] Level 2, 60% load: Rounded up to 7 units. Following the principle of symmetrical start-stop, with 2 units as the smallest unit, 8 units are actually activated.

[0148] Level 3, 90% load: Rounded up to 11 units. Following the principle of symmetrical start-stop, 12 units were actually activated.

[0149] Level 4, 100% load: Rounded up to 12 units. Following the principle of symmetrical start / stop, 12 units are actually activated. Since 12 is an even number, no adjustment is needed.

[0150] During the third stage of operation at 90% load, the measured feed pressure of the hydrocyclone was 0.088 MPa. This value is within the target range of 0.06 MPa to 0.10 MPa, and the sedimentation is umbrella-shaped, indicating the best classification effect. During the fourth stage of operation at 100% load, the measured feed pressure of the hydrocyclone was 0.095 MPa. This value is close to the upper limit of the target range. Following the adjustment rules described in step S29, the operator temporarily did not increase the number of hydrocyclones in operation and continued monitoring. After 2 hours of operation, the feed pressure stabilized at 0.093 MPa, within the target range.

[0151] This embodiment uses formula (7) for quantitative calculation and the principle of symmetrical start-stop to ensure that the number of hydrocyclones in operation is precisely matched with the processing capacity at each stage, avoiding deviations caused by estimation based on experience. The actual operating data at each stage forms a complete correspondence between "processing capacity - number of hydrocyclones in operation - feed pressure", providing a directly applicable operational basis for formal production.

[0152] Example 3: Based on Example 1, Example 3 further optimizes the closed-loop feedback control of the ball replenishment amount and motor power.

[0153] In this embodiment, the total amount of balls replenished during the operation of the ball mill at the fourth stage of 100% load is... Tons. Calculate the daily ball replenishment amount according to formula (18). Tons per day. The theoretical ball replenishment volume per shift is calculated according to formula (19). Tons per shift.

[0154] On the third day of the second shift during the fourth-level 100% load phase, after the ball replenishment operation was completed, the real-time motor power monitoring system detected that the motor power was 98% of the rated value. The theoretical power calculated based on the current filling rate was 93% of the rated value. The actual power was 5 percentage points higher than the theoretical power.

[0155] The central control DCS system calculates the power deviation correction coefficient according to formula (22): ; The central control DCS system adjusted the theoretical ball replenishment volume for the third shift on the third day to: ; On the third day, the third shift actually added a total of 7 tons, with the remaining 0.13 tons carried over to the next shift.

[0156] After the ball replenishment operation on the 4th shift of the 3rd day, the motor power dropped to 95% of the rated value. The deviation between the actual power and the theoretical power narrowed to 2 percentage points. The central control DCS system stopped adjusting and resumed execution according to the original theoretical ball replenishment volume.

[0157] This embodiment, through real-time calculation and dynamic adjustment of the power deviation correction coefficient, enables the ball replenishment amount to respond to changes in the actual load state of the mill, forming a closed-loop control loop of "ball replenishment → power response → deviation detection → ball replenishment correction". This closed-loop control mechanism further improves the accuracy of filling rate control, reducing the deviation between the cumulative total ball replenishment amount at each stage and the theoretical calculation value from within 5% to within 3%.

[0158] Comparative Example: A heavy-load commissioning was conducted on the same ore dressing plant using a traditional, extensive, step-by-step method. The commissioning was divided into three phases: 3 days of operation at 50% load, 5 days of operation at 80% load, and 7 days of operation at 100% load. A constant ball replenishment system was adopted, with fixed daily replenishment. millimeters and Five tons of each of the two types of steel balls (one millimeter in diameter) were used, with no phased adjustments. Equipment parameters for high-altitude environments were not corrected; the equipment selection and protection thresholds for plains areas were directly adopted.

[0159] Test run results: At 50% load, due to a relatively large amount of ball replenishment compared to the low throughput, steel balls gradually accumulated inside the mill. On the third day, the motor current reached 108% of the rated value, triggering an overcurrent trip. At 80% load, due to excessive steel ball accumulation in the early stages, the mill's startup torque was too high, and the main bearing temperature reached 72 degrees Celsius on the second day, exceeding the 70-degree Celsius alarm threshold. At 100% load, due to insufficient motor cooling in the high-altitude environment, coupled with the increased mill load from the accumulated steel balls, the motor winding temperature reached 132 degrees Celsius on the fourth day, triggering an overheat protection trip. The test run was forced to be interrupted three times, extending the total time to 25 days, ultimately failing to complete the 15-day continuous full-load operation test.

[0160] Industrial Applicability: The method for load progression control and steel ball replenishment during heavy-load commissioning of high-altitude concentrators provided in this invention can be used for heavy-load commissioning of grinding systems in various newly built or expanded concentrators at altitudes ranging from 2000 meters to 5500 meters. This method is not only applicable to copper concentrators but also to concentrators of other metal ores such as iron ore, lead-zinc ore, and molybdenum ore. The method of this invention has clear steps, adjustable parameters, and a wide range of applications, possessing good industrial practical value and promising prospects for promotion.

Claims

1. A method for load progression control during heavy-load commissioning of a grinding system in a plateau ore dressing plant, characterized in that, include: Determine the altitude of the test site; Based on the measured altitude, the grinding system was adapted for the high-altitude environment. After completing the adaptation to the high-altitude environment, the heavy load test process was set into four progressively increasing load stages according to the load percentage from low to high. The load increase gradient between each load stage was 30 percentage points, and each load stage was set with a corresponding preset running time. The test operation for each of the four load stages shall be performed in sequence from low to high. After each load phase reaches the corresponding preset running time, an inter-phase shutdown check is performed. After the inter-phase shutdown inspection is completed and passes acceptance, a phase switch review is performed to determine whether the current load phase meets the switch conditions for entering the next load phase. When all the switching conditions are met, the process is allowed to proceed to the next load phase and continue the test run until all load phases are completed.

2. The method for load progression control during heavy-load joint commissioning of a grinding system in a plateau ore dressing plant according to claim 1, characterized in that, The high-altitude environment adaptation includes the following correction methods: Calculating a motor power correction coefficient based on the measured altitude, multiplying the plain design power by the motor power correction coefficient and adding a margin factor to obtain the high-altitude selected power; calculating a creepage distance altitude correction coefficient based on the measured altitude, multiplying the standard creepage distance in the plain environment by the creepage distance altitude correction coefficient to obtain the corrected creepage distance; calculating an electrical clearance altitude correction coefficient based on the measured altitude, multiplying the standard electrical clearance in the plain environment by the electrical clearance altitude correction coefficient to obtain the corrected electrical clearance; and lowering the motor winding temperature alarm value, main bearing temperature alarm value, and gearbox oil temperature alarm value by a pre-set temperature difference value according to the high-altitude environment.

3. The method for load progression control during heavy-load joint commissioning of a grinding system in a plateau ore dressing plant according to claim 1, characterized in that, The four progressively increasing load phases are, in order of increasing load percentage, the first load phase, the second load phase, the third load phase, and the fourth load phase; the first load phase has a load percentage of 30% of the design full load and a preset operating duration of 5 days. The load percentage for the second-level load phase is 60% of the design full load, and the preset operating time is 5 days. The load percentage of the third load stage is 90% of the design full load, and the preset operating time is 10 days. The load percentage of the fourth load stage is 100% of the design full load, and the preset operating time is 15 days.

4. The method for load progression control during heavy-load joint commissioning of a grinding system in a plateau ore dressing plant according to claim 1, characterized in that, The switching conditions for the phase switching review include: no equipment damage accidents occurred during the operation of the equipment in the current load phase; all problems exposed in the current load phase have been resolved and passed acceptance; all equipment operating parameters at the end of the current load phase are within the allowable range; and the operators have passed the operation skills assessment for the current load phase.

5. The method for load progression control during heavy-load joint commissioning of a grinding system in a plateau concentrator according to any one of claims 1 to 4, characterized in that, During the initial commissioning operation at the first load stage, the semi-autogenous mill does not perform initial ball loading, and its filling rate is zero. Upon entering the second load stage, the semi-autogenous mill begins initial ball loading with a filling rate of not less than 4%. Upon entering the third load stage, the semi-autogenous mill supplements the initial ball loading to achieve a filling rate of not less than 8%. Upon entering the fourth load stage, the semi-autogenous mill adds the remaining initial ball loading to achieve the design full-load filling rate.

6. A method for replenishing steel balls during heavy-load joint commissioning of a grinding system in a high-altitude ore dressing plant using the method described in any one of claims 1 to 5, characterized in that, include: Obtain the cumulative throughput of each grinding equipment at each load stage; Determine the unit wear consumption of steel balls for each grinding equipment; Multiply the cumulative processing volume of the aforementioned stage by the corresponding steel ball wear consumption to obtain the total amount of ball replenishment for the corresponding grinding equipment at the corresponding load stage; Obtain the mass ratio of each grade of ball diameter in the initial ball charge of each grinding equipment; The total amount of replenished balls is allocated according to the mass ratio of each ball diameter in the initial ball load to obtain the replenishment amount of each ball diameter for the corresponding grinding equipment at the corresponding load stage.

7. The method for replenishing steel balls during heavy-load linkage commissioning of a grinding system in a plateau ore dressing plant according to claim 6, characterized in that, The ball mill is designed to have a preset total initial ball load at full load. The ball mill is initially loaded in stages: 30% of the total initial ball load is loaded in the first load stage, 30% in the second load stage, 30% in the third load stage, and 10% in the fourth load stage.

8. The method for replenishing steel balls during heavy-load linkage test run of the grinding system in a plateau ore dressing plant according to claim 6, characterized in that, The replenishment of grinding equipment is carried out on a shift basis. The replenishment amount for each shift is in whole tons, and any balance less than 1 ton is carried over to the next shift. After the end of each load phase, the percentage deviation between the actual replenishment amount for that load phase and the total replenishment amount is calculated. When the deviation percentage exceeds 5%, the replenishment amount is adjusted in the replenishment plan for the next load phase.

9. The method for replenishing steel balls during heavy-load linkage commissioning of a grinding system in a plateau ore dressing plant according to claim 6, characterized in that, It also includes the steps for determining the number of hydrocyclones in operation: obtaining the hourly throughput and the designed throughput of a single hydrocyclone during the load period, dividing the hourly throughput by the designed throughput of a single hydrocyclone and rounding up to obtain the theoretical number of hydrocyclones in operation; when the theoretical number of hydrocyclones in operation is odd, the actual number of hydrocyclones in operation is the theoretical number of hydrocyclones in operation plus 1 to ensure even symmetry. During operation at each load stage, the feed pressure of the hydrocyclone is monitored in real time. When the feed pressure exceeds the preset target range, the number of hydrocyclones turned on is adjusted.

10. The method for replenishing steel balls during heavy-load linkage commissioning of a grinding system in a plateau ore dressing plant according to claim 6, characterized in that, It also includes dynamic monitoring and adjustment steps for filling rate: During operation at each load stage, the mill motor current is monitored in real time. When the mill motor current is lower than 80% of the rated value, it is determined that the filling rate is too low, and the amount of balls added in the next ball replenishment operation is increased; when the mill motor current is higher than 105% of the rated value, it is determined that the filling rate is too high, the ball replenishment operation is suspended, and it is checked whether there is excessive accumulation of steel balls in the mill.

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