Automatic control method for roller press and ball mill combined grinding system

Abstract

The present invention discloses an automatic control method for a roller press and a ball mill combined grinding system, which mainly includes automatic control when the amount of fine powder in the pre-grinding system increases, when the temperature of the cement discharged from the mill is high, and when the specific surface area of ​​the finished product is unqualified when the working condition is saturated grinding, and then reaches the control conditions required for the normal working condition. The present invention solves the technical problems of the prior art in that automation is not achieved, the quality and efficiency are poor, and the cost is high through the automatic control method for a roller press and a ball mill combined grinding system.

Description

Technical Field

[0001] The invention relates to the field of combined grinding, and in particular to an automatic control method for a combined grinding system of a roller press and a ball mill. Background Art

[0002] Roller press is a new type of energy-saving cement grinding equipment. The material is fed from above the two squeezing rollers of the roller press, and is continuously brought into the gap between the rollers by the squeezing rollers. After being subjected to the high pressure of 100-150MPa, it becomes a dense cake and is discharged from the bottom of the machine. The ball mill is the key equipment for crushing the material after it is broken. The roller press and the ball mill together form a grinding system for crushing and grinding the material. If you want to optimize the cement, you need to control the roller press and the ball mill to adapt them.

[0003] The cement mill control system currently used in cement plants still relies on experienced operators to adjust the system. However, due to the limitations of human physiological functions, it is impossible for humans to operate the system with high concentration for 8 hours continuously, making it difficult to ensure the continuous and stable operation of the system. The system operation method will be rough, and the quality and output will not reach the optimal values. Once the operator does not operate the system for a long time, the cement quality will be unqualified, the output will be reduced, and the system will crash and stop. In addition, since the cement mill system frequently requires manual intervention, each production line needs to be equipped with 5 operators, which has huge labor costs. Summary of the invention

[0004] The object of the present invention is to provide an automatic control method for a roller press and ball mill combined grinding system to solve the technical problems of the prior art that automation is not achieved, quality and efficiency are poor, and cost is high.

[0005] To achieve the above object, the present invention provides an automatic control method for a roller press and ball mill combined grinding system, including the following strategies:

[0006] S1. When the amount of fine powder in the pre-grinding system increases, the true or false is judged according to the steady flow bin and circulating bucket lifting current, and whether to trigger the fine powder control strategy is selected;

[0007] S2: When the temperature of cement leaving the mill is high, the authenticity is judged according to the temperature of the gas and material at the mill outlet, and whether to trigger the high cement temperature control strategy is selected;

[0008] S3, when the working condition is full grinding, judge the truth or falseness according to the mill current, the negative pressure of the grinding head and the current of the grinding bucket, and choose whether to trigger the full grinding control strategy;

[0009] S4. If the surface area of ​​the finished product is unqualified, choose whether to trigger the strategy according to the surface area and fineness value of the finished product to optimize the surface area of ​​the finished product;

[0010] S5. Under normal working conditions, when the above S1-S4 conditions are all false, this condition is true, and it is selected whether to trigger the normal working condition strategy;

[0011] The S1-S5 sends the judgment result to the intelligent control system, and then identifies the cement mill working condition through the judgment condition, and calls the corresponding control strategy control system.

[0012] In S1, when both the steady flow bin reaches the set lower limit and the circulating bucket current reaches the set upper limit, it is determined that the pre-grinding system has a large amount of powder and the roller press has a large amount of throughput, and the following steps are performed:

[0013] S11, control the opening of the inclined plug plate, and reduce the opening of the inclined plug plate by 5% / 10s until the circulating bucket current returns to the set value;

[0014] S12, control the speed of the circulating fan. To avoid material slippage, the circulating fan is prohibited from slowing down. As the feeding increases and the inclined plate descends, the circulating fan starts to pull air until the bin position and circulating bucket lifting current return to the set range;

[0015] S13, control the feeding amount. As the amount of fine powder increases, the feeding amount is increased. When the bin position returns to the set range, stop increasing the feeding amount.

[0016] Further in S2, when both the outlet gas temperature is higher than the set value and the outlet material temperature is higher than the set value are met at the same time, it is judged as the working condition of high outlet cement temperature. At this time, the tail exhaust air volume is triggered to be controlled. When the tail exhaust air is increased by 3Hz and the gas and material temperatures return to the set values, the air volume is gradually restored at a reduction rate of 0.2Hz / 15s.

[0017] Furthermore, in S3, when two of the three conditions, namely, the ball mill current is lower than the set value, the outlet elevator current is lower than the set value, and the grinding head negative pressure is lower than the set value, are met at the same time, it is judged as a saturated operating condition. At this time, the circulating air volume is reduced by 15%. After the parameters return to normal conditions, the air volume is restored in increments of 0.5Hz / 15s; the feeding amount is reduced by 15%. After the parameters return to normal conditions, it is restored in increments of 1t / 15s; the circulating air volume is reduced by 10%. After the parameters return to normal conditions, the speed is restored in increments of 0.5Hz / 15s.

[0018] Furthermore, the comparison table results in S4 include:

[0019] If the current tested specific surface area is ≤ the lower limit, the control target value of cement specific surface area is +3 on the original basis;

[0020] If the current tested specific surface area is greater than the lower limit and less than the lower limit + 5, the control target value of cement specific surface area will be increased by 1 on the original basis;

[0021] If the current test specific surface area is ≥ the lower limit value + 5 and less than the lower limit value + 10, the control target value of cement specific surface area is -1 on the original basis;

[0022] If the current test specific surface area is ≥ the lower limit + 10 and less than the lower limit + 15, the control target value of cement specific surface area is -2 on the original basis;

[0023] If the current tested specific surface area is ≥ the lower limit value + 15, the cement specific surface area control target value is -4 on the original basis.

[0024] Furthermore, in S5, the control strategies under normal working conditions are divided into steady flow bin position control strategy, grinding head hoist current control strategy and grinding tail circulation compliance control strategy, among which the steady flow bin position control strategy is divided into:

[0025] The feeder enters the steady flow position with an upper limit of 20T and a lower limit of 17T at a feeding rate of 225t / h and 105t / h under the controller with a gain of 0.05, a lag time of 90s and a steady state time of 600s.

[0026] The circulating fan enters a steady flow position with an upper limit of 20T and a lower limit of 17T at a rotation rate of 38Hz and 34Hz under the controller with a gain of -0.1, a lag time of 120s and a steady-state time of 90s.

[0027] Furthermore, the current control strategy of the grinding head hoist is divided into:

[0028] The feeder reaches the upper limit of 210A and the lower limit of 190A of the grinding head bucket lifting current value under the condition of the controller with a gain of 0.5, a lag time of 30s and a steady-state time of 5s with a feeding rate of 220t / h and a lower limit of 205t / h;

[0029] The roller press has an upper limit of 44Hz and a lower limit of 40Hz. The opening of the inclined plug plate of the roller press reaches an upper limit of 210A and a lower limit of 190A for the grinding head bucket lifting current when the controller has a gain of 1.5, a lag time of 10s and a steady-state time of 10s.

[0030] Furthermore, the grinding tail cycle complies with the control strategy as follows:

[0031] The circulating fan reaches the upper limit of 160A and the lower limit of 145A at the current of the mill tail hoist with the upper limit of 39Hz and the lower limit of 32Hz under the condition of the controller gain of 15, lag time of 900s and steady-state time of 100s, and automatically optimizes the target value of the tail hoist current;

[0032] The powder concentrator reaches the upper limit of 160A and the lower limit of 145A of the mill tail hoist current value with the upper limit of 39Hz and the lower limit of 32Hz under the controller with the gain of 10, the lag time of 100s and the steady-state time of 15s, and automatically optimizes the target value of the tail hoist current;

[0033] The main exhaust fan reaches the upper limit of 160A and the lower limit of 145A for the mill tail hoist current with an upper limit of 44Hz and a lower limit of 37Hz under the conditions of a controller gain of -12, a lag time of 120s and a steady-state time of 40s, and automatically optimizes the target value of the tail hoist current.

[0034] Furthermore, the control logic of automatically optimizing the target value of the tail hoist current, automatically optimizing the target value of the tail hoist current, and automatically optimizing the target value of the tail hoist current is:

[0035] If the steady-current bin weight measurement value is less than the bin weight lower limit, the tail mill hoist current target value = current lower limit + (current upper limit - current lower limit) * 0.25;

[0036] If the steady-current bin weight measurement value is greater than the bin weight lower limit, the tail mill hoist current target value = current lower limit + (current upper limit - current lower limit) * 0.75;

[0037] When the bucket lifting current is ≤160A and the current is ≥145A, the circulating fan controls the mill tail hoist current to be in a steady state at the target value;

[0038] When the bucket lifting current is less than 145A, or the bucket lifting current is greater than 160A, the main exhaust fan and the high-efficiency powder classifier are used to simultaneously control the mill tail circulation load so as not to exceed the limit.

[0039] Based on the above technical solution, the embodiments of the present invention can produce the following technical effects:

[0040] (1) The present invention provides an automatic control method for a roller press and ball mill combined grinding system, which automatically optimizes the specific surface area. When unqualified finished products appear, the system is guided to accelerate adjustment. When the finished products are qualified, over-grinding can be avoided, thereby maximizing the unit-hourly output.

[0041] (2) The present invention provides an automatic control method for a roller press and ball mill combined grinding system. Through the experience of many excellent operators, five working conditions are summarized, including normal working conditions, working conditions with increased fine powder content, working conditions with high cement temperature, working conditions with saturated grinding, and unqualified finished product ratio. Five optimal operation strategies are formulated and developed into software programs. The software programs can identify working conditions through their characteristic conditions, call corresponding strategies, and use computer programs to create a virtual operator to simulate manual operation, achieve 24-hour precise adjustment, improve system stability, and improve quality and output.

[0042] (3) The present invention provides an automatic control method for a roller press and ball mill combined grinding system, which completely replaces the operator during normal operation, realizes fully automatic intelligent operation, and reduces the manpower cost of the enterprise. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a schematic diagram of a process of a roller press and ball mill combined grinding system according to an embodiment of the present invention;

[0044] Figure 2 1 is a schematic diagram of the control strategy flow under normal working conditions of the pre-grinding system of an embodiment of the present invention;

[0045] Figure 3 1 is a schematic flow chart of a control strategy for increasing the amount of fine powder in a pre-grinding system according to an embodiment of the present invention;

[0046] Figure 4 It is a flow chart of a control strategy for high cement outlet temperature according to an embodiment of the present invention;

[0047] Figure 5 It is a flow chart of the control strategy of the full grinding condition according to an embodiment of the present invention;

[0048] Figure 6 It is a schematic flow chart of the automatic optimization control strategy of the specific surface area of ​​the finished product according to the embodiment of the present invention;

[0049] Figure 7 It is a schematic diagram of the control strategy flow of the steady flow bin position under normal working conditions of an embodiment of the present invention;

[0050] Figure 8 1 is a schematic diagram of a control strategy flow of a grinding head hoisting machine current under normal working conditions according to an embodiment of the present invention;

[0051] Fig. 9 It is a schematic flow chart of the control strategy of the mill tail circulation load under normal working conditions in an embodiment of the present invention. DETAILED DESCRIPTION

[0052] In order to better understand the purpose, structure and function of the present invention, the automatic control method of the roller press and ball mill combined grinding system of the present invention is further described in detail below in conjunction with the accompanying drawings.

[0053] In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0054] As shown in the figure, the present invention provides an automatic control method for a roller press and ball mill combined grinding system, including the following strategies:

[0055] S1. When the amount of fine powder in the pre-grinding system increases, the true or false is judged according to the steady flow bin and circulating bucket lifting current, and whether to trigger the fine powder control strategy is selected;

[0056] S2: When the temperature of cement leaving the mill is high, the authenticity is judged according to the temperature of the gas and material at the mill outlet, and whether to trigger the high cement temperature control strategy is selected;

[0057] S3, when the working condition is full grinding, judge the truth or falseness according to the mill current, the negative pressure of the grinding head and the current of the grinding bucket, and choose whether to trigger the full grinding control strategy;

[0058] S4. If the surface area of ​​the finished product is unqualified, choose whether to trigger the strategy according to the surface area and fineness value of the finished product to optimize the surface area of ​​the finished product;

[0059] S5. Under normal working conditions, when the above S1-S4 conditions are all false, this condition is true, and it is selected whether to trigger the normal working condition strategy;

[0060] The S1-S5 sends the judgment result to the intelligent control system, and then identifies the cement mill working condition through the judgment condition, and calls the corresponding control strategy control system.

[0061] In S1, when both the steady flow bin reaches the set lower limit and the circulating bucket current reaches the set upper limit, it is determined that the pre-grinding system has a large amount of powder and the roller press has a large amount of throughput, and the following steps are performed:

[0062] S11, control the opening of the inclined plug plate, and reduce the opening of the inclined plug plate by 5% / 10s until the circulating bucket current returns to the set value;

[0063] S12, control the speed of the circulating fan. To avoid material slippage, the circulating fan is prohibited from slowing down. As the feeding increases and the inclined plate descends, the circulating fan starts to pull air until the bin position and circulating bucket lifting current return to the set range;

[0064] S13, control the feeding amount. As the amount of fine powder increases, the feeding amount is increased. When the bin position returns to the set range, stop increasing the feeding amount.

[0065] Further in S2, when both the outlet gas temperature is higher than the set value and the outlet material temperature is higher than the set value are met at the same time, it is judged as the working condition of high outlet cement temperature. At this time, the tail exhaust air volume is triggered to be controlled. When the tail exhaust air is increased by 3Hz and the gas and material temperatures return to the set values, the air volume is gradually restored at a reduction rate of 0.2Hz / 15s.

[0066] Furthermore, in S3, when two of the three conditions, namely, the ball mill current is lower than the set value, the outlet elevator current is lower than the set value, and the grinding head negative pressure is lower than the set value, are met at the same time, it is judged as a saturated operating condition. At this time, the circulating air volume is reduced by 15%. After the parameters return to normal conditions, the air volume is restored in increments of 0.5Hz / 15s; the feeding amount is reduced by 15%. After the parameters return to normal conditions, it is restored in increments of 1t / 15s; the circulating air volume is reduced by 10%. After the parameters return to normal conditions, the speed is restored in increments of 0.5Hz / 15s.

[0067] Furthermore, the comparison table results in S4 include:

[0068] If the current tested specific surface area is ≤ the lower limit, the control target value of cement specific surface area is +3 on the original basis;

[0069] If the current tested specific surface area is greater than the lower limit and less than the lower limit + 5, the control target value of cement specific surface area will be increased by 1 on the original basis;

[0070] If the current test specific surface area is ≥ the lower limit value + 5 and less than the lower limit value + 10, the control target value of cement specific surface area is -1 on the original basis;

[0071] If the current test specific surface area is ≥ the lower limit + 10 and less than the lower limit + 15, the control target value of cement specific surface area is -2 on the original basis;

[0072] If the current tested specific surface area is ≥ the lower limit value + 15, the cement specific surface area control target value is -4 on the original basis.

[0073] Furthermore, in S5, the control strategies under normal working conditions are divided into steady flow bin position control strategy, grinding head hoist current control strategy and grinding tail circulation compliance control strategy, among which the steady flow bin position control strategy is divided into:

[0074] The feeder enters the steady flow position with an upper limit of 20T and a lower limit of 17T at a feeding rate of 225t / h and 105t / h under the controller with a gain of 0.05, a lag time of 90s and a steady state time of 600s.

[0075] The circulating fan enters a steady flow position with an upper limit of 20T and a lower limit of 17T at a rotation rate of 38Hz and 34Hz under the controller with a gain of -0.1, a lag time of 120s and a steady-state time of 90s.

[0076] Furthermore, the current control strategy of the grinding head hoist is divided into:

[0077] The feeder reaches the upper limit of 210A and the lower limit of 190A of the grinding head bucket lifting current value under the condition of the controller with a gain of 0.5, a lag time of 30s and a steady-state time of 5s with a feeding rate of 220t / h and a lower limit of 205t / h;

[0078] The roller press has an upper limit of 44Hz and a lower limit of 40Hz. The opening of the inclined plug plate of the roller press reaches an upper limit of 210A and a lower limit of 190A for the grinding head bucket lifting current when the controller has a gain of 1.5, a lag time of 10s and a steady-state time of 10s.

[0079] Furthermore, the grinding tail cycle complies with the control strategy as follows:

[0080] The circulating fan reaches the upper limit of 160A and the lower limit of 145A at the current of the mill tail hoist with the upper limit of 39Hz and the lower limit of 32Hz under the condition of the controller gain of 15, lag time of 900s and steady-state time of 100s, and automatically optimizes the target value of the tail hoist current;

[0081] The powder concentrator reaches the upper limit of 160A and the lower limit of 145A of the mill tail hoist current value with the upper limit of 39Hz and the lower limit of 32Hz under the controller with the gain of 10, the lag time of 100s and the steady-state time of 15s, and automatically optimizes the target value of the tail hoist current;

[0082] The main exhaust fan reaches the upper limit of 160A and the lower limit of 145A for the mill tail hoist current with an upper limit of 44Hz and a lower limit of 37Hz under the conditions of a controller gain of -12, a lag time of 120s and a steady-state time of 40s, and automatically optimizes the target value of the tail hoist current.

[0083] Furthermore, the control logic of automatically optimizing the target value of the tail hoist current, automatically optimizing the target value of the tail hoist current, and automatically optimizing the target value of the tail hoist current is:

[0084] If the steady-current bin weight measurement value is less than the bin weight lower limit, the tail mill hoist current target value = current lower limit + (current upper limit - current lower limit) * 0.25;

[0085] If the steady-current bin weight measurement value is greater than the bin weight lower limit, the tail mill hoist current target value = current lower limit + (current upper limit - current lower limit) * 0.75;

[0086] When the bucket lifting current is ≤160A and the current is ≥145A, the circulating fan controls the mill tail hoist current to be in a steady state at the target value;

[0087] When the bucket lifting current is less than 145A, or the bucket lifting current is greater than 160A, the main exhaust fan and the high-efficiency powder classifier are used to simultaneously control the mill tail circulation load so as not to exceed the limit.

[0088] It is to be understood that the present invention is described by some embodiments, and it is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims

1. An automatic control method for a roller press and ball mill combined grinding system, characterized in that: These strategies include: S1. When the amount of fine powder in the pre-grinding system increases, the steady flow bin and the circulating bucket current are used to determine whether to trigger the fine powder control strategy. In S1, when the steady flow bin reaches the set lower limit and the circulating bucket current reaches the set upper limit, it is determined that the pre-grinding system has more powder and the roller press has a larger throughput, and the following steps are performed: S11, control the opening of the inclined plug plate, and reduce the opening of the inclined plug plate by 5% / 10s until the circulating bucket current returns to the set value; S12, control the speed of the circulating fan. To avoid material slippage, the circulating fan is prohibited from slowing down. As the feeding increases and the inclined plate descends, the circulating fan starts to draw air until the bin position and circulating bucket lifting current return to the set range; S13, control the feeding amount. Due to the increase of fine powder, the feeding amount is increased. After the bin position returns to the set range, stop increasing the feeding amount. S2, when the temperature of the cement out of the mill is high, judge the truth or false according to the outlet gas and material temperature of the mill, and choose whether to trigger the high cement temperature control strategy. In S2, when the two conditions of the outlet gas temperature higher than the set value and the outlet material temperature higher than the set value are met at the same time, it is judged as the working condition of the high outlet cement temperature. At this time, the tail exhaust air volume is triggered to control. When the tail exhaust air is increased by 3Hz, the gas and material temperatures return to the set values, and the air volume is gradually restored at a reduction of 0.2Hz / 15s; S3, when the working condition is full grinding, judge the truth or falseness according to the mill current, the negative pressure of the grinding head and the current of the grinding bucket, and choose whether to trigger the full grinding control strategy; S4. If the surface area of ​​the finished product is unqualified, choose whether to trigger the strategy according to the surface area and fineness value of the finished product to optimize the surface area of ​​the finished product; S5. Under normal working conditions, when the above S1-S4 conditions are all false, this condition is true, and it is selected whether to trigger the normal working condition strategy; S1-S5 sends the judgment result to the intelligent control system, and then identifies the cement mill working condition through the judgment condition, and calls the corresponding control strategy control system; In S5, the control strategies under normal working conditions are divided into steady flow bin position control strategy, grinding head hoist current control strategy and grinding tail circulation compliance control strategy, among which the steady flow bin position control strategy is divided into: The feeder enters the steady flow position with an upper limit of 20T and a lower limit of 17T at a feeding rate of 225t / h and 105t / h under the controller with a gain of 0.05, a lag time of 90s and a steady state time of 600s. The circulation fan enters the steady flow position with an upper limit of 20T and a lower limit of 17T at a rotation rate of 38Hz and 34Hz under the controller with a gain of -0.1, a lag time of 120s and a steady state time of 90s. The grinding head hoist current control strategy is divided into: The feeder reaches the upper limit of 210A and the lower limit of 190A of the grinding head bucket lifting current value under the condition of the controller with a gain of 0.5, a lag time of 30s and a steady-state time of 5s with a feeding rate of 220t / h and a lower limit of 205t / h; The roller press has an upper limit of 44Hz and a lower limit of 40Hz. The opening of the inclined plug plate of the roller press reaches an upper limit of 210A and a lower limit of 190A for the grinding head bucket lifting current when the controller has a gain of 1.5, a lag time of 10s, and a steady-state time of 10s. The tail grinding cycle complies with the control strategy as follows: The circulating fan reaches the upper limit of 160A and the lower limit of 145A at the current of the mill tail hoist with the upper limit of 39Hz and the lower limit of 32Hz under the condition of the controller gain of 15, lag time of 900s and steady-state time of 100s, and automatically optimizes the target value of the tail hoist current; The powder concentrator reaches the upper limit of 160A and the lower limit of 145A of the mill tail hoist current value with the upper limit of 39Hz and the lower limit of 32Hz under the controller with the gain of 10, the lag time of 100s and the steady-state time of 15s, and automatically optimizes the target value of the tail hoist current; The main exhaust fan reaches the upper limit of 160A and the lower limit of 145A for the mill tail hoist current with the upper limit of 44Hz and the lower limit of 37Hz under the condition of the controller gain of -12, lag time of 120s and steady-state time of 40s, and automatically optimizes the target value of the tail hoist current; The control logic of the automatic optimization tail hoist current target value, the automatic optimization tail hoist current target value and the automatic optimization tail hoist current target value is: If the steady-current bin weight measurement value is less than the bin weight lower limit, the tail mill hoist current target value = current lower limit + (current upper limit - current lower limit) * 0.25; If the steady-current bin weight measurement value is greater than the bin weight lower limit, the tail mill hoist current target value = current lower limit + (current upper limit - current lower limit) * 0.75; When the bucket lifting current is ≤160A and the current is ≥145A, the circulating fan controls the mill tail hoist current to be in a steady state at the target value; When the bucket lifting current is less than 145A, or the bucket lifting current is greater than 160A, the main exhaust fan and the high-efficiency powder classifier are used to simultaneously control the mill tail circulation load so as not to exceed the limit.

2. The automatic control method of a roller press and ball mill combined grinding system according to claim 1, characterized in that: In S3, when two of the three conditions, namely, the ball mill current is lower than the set value, the outlet elevator current is lower than the set value, and the grinding head negative pressure is lower than the set value, are met at the same time, it is determined to be a saturated operating condition. At this time, the circulating air volume is reduced by 15%. After the parameters return to normal operating conditions, the air volume is restored in increments of 0.5Hz / 15s; the feeding amount is reduced by 15%. After the parameters return to normal operating conditions, it is restored in increments of 1t / 15s; the circulating air volume is reduced by 10%. After the parameters return to normal operating conditions, the speed is restored in increments of 0.5Hz / 15s.

3. The automatic control method of a roller press and ball mill combined grinding system according to claim 1, characterized in that: The comparison table results in S4 include: If the current tested specific surface area is ≤ the lower limit, the control target value of cement specific surface area is +3 on the original basis; If the current tested specific surface area is greater than the lower limit and less than the lower limit + 5, the control target value of cement specific surface area will be increased by 1 on the original basis; If the current test specific surface area is ≥ the lower limit + 5 and less than the lower limit + 10, the control target value of cement specific surface area is -1 on the original basis; If the current test specific surface area is ≥ the lower limit value + 10 and less than the lower limit value + 15, the control target value of cement specific surface area is -2 on the original basis; If the current tested specific surface area is ≥ the lower limit value + 15, the cement specific surface area control target value is -4 on the original basis.

Images