SU1039560A1 - Method of automatic control of wet ore disintegration process in ball mill - Google Patents

Abstract

A METHOD FOR AUTOMATIC CONTROL OF THE PROCESS OF WET MILLING OF ORE IN A BALL MILL, Including changing the pressure of the oil wedge in the discharge bearing, changing the ore consumption in proportion to the deviation of the oil wedge from the set value and maintaining the ratio of ore flow to the area of the pool. water into the mill, characterized in that, in order to increase the control accuracy by maintaining a predetermined fractional composition of the solid phase in the discharge, Contents in the sink fraktsii.zadannoy size classifier, averaged over a specified period deviation of the measured contents from a predetermined value. , J III periodically measure the moisture and fractional composition of the ore, change the water consumption in the classifier directly proportional to the deviation of the measured content of the fraction of a given size from the specified value, and during the change in ore consumption adjust its consumption by the value calculated by the formula O 1 -In and where the consumption of ore; the measured content of the fraction of a given size in the ore} 2 the established content of the JV fraction of a given size of the solid phase in the discharge of the classifier; 8 .- measured ore moisture; C-, –2 proportionality coefficients, and the proportionality coefficient Cd is corrected proportionally from 09 to the measured average for a specified period of deviation from the measured fraction in the discharge of the fraction of a given size from the specified value. / /

Description

The invention relates to the automatic control of the process of mokog grinding ore in a ball mill working in conjunction with a classifier, and can be used in the processing of apatite and in other industries with similar technology.

There is a known method for controlling the wet grinding process, which includes stabilizing the sound parameter of the mill of the classifier’s drainage density, measuring the ore and water consumption supplied to the mill, water consumption to the classifier, calculating the liquid to solid ratio in the classifier drain, and changing the water consumption to the mill. In this method, the measured value of ore consumption per mill is multiplied by the calculated ratio of liquid to solid in the classifier discharge, the measured amount of water flow is subtracted from the value of the resulting product, and the change in water per mill is equal to the computational difference Cl

The disadvantage of this method is that with. By changing the grindability of the raw material, the circulation and total load of the mill is changed. At the same time, the water consumption in the mill does not change, which degrades the quality of maintaining the classifier discharge.

Closest to the invention, the technical essence is a method for automatically controlling the process of wet grinding of ore in a ball mill, including measuring the oil wedge pressure in the discharge bearing, changing the ore consumption is proportional to the deviation of the oil wedge pressure from the set value and maintaining the specified ratio between the ore consumption and water into the mill by affecting the flow of water into the mill. This method includes measuring the density of the classifier discharge, measuring the circulation load, changing the flow rate of pulp into the mill, and changing the flow rate of water into the mill is proportional to the deviation of the discharge density from the specified value. In it, the value of the circulation load is determined by the difference in the mass flow rate and the moisture content of the sands discharged from the classifier, and the flow of water into the mill additionally corrects the PS moisture content hecKOB 2.

The disadvantage of this method is the low accuracy of maintaining a given size in the discharge of the classifier because of the low accuracy of the measurement of the weight flow and the moisture holding sand.

The disadvantage of these methods is that they do not allow obtaining a classifier discharge with a predetermined content of the established solid phase fraction. For the grinding of apatite ore, this is one of the requirements for the subsequent (with these technological limits on the quality of grinding.

. The purpose of the invention is to increase the control accuracy by maintaining a predetermined fractional composition of the solid phase in the discharge.

The goal is achieved in that according to the method of automatically controlling the process of wet grinding of ore in a ball mill, including measuring the pressure of the oil wedge in the discharge bearing, the change in ore consumption is proportional to the deviation of the pressure of the oil wedge from the set value and maintaining the specified ratio between the ore and water consumption in the mill by affecting the flow rate of water in the mill, the content in the discharge of the classifier of fractions of a given size is measured, the deviation, average for a specified period, the moisture content and the fractional composition of the ore are periodically measured, the flow rate of the ore is changed into a classifier, directly proportional to the deviation of the measured content of the fraction of a given size from the preset value, and during the ore consumption change, the flow rate is calculated by the value calculated formula

(SC. ,,)

O. 1-B

de O. ore consumption; To the measured content of the fraction of a given size in the ore;

H

the established content of the fraction of a given size of the solid phase in the discharge of the classifier;

In measured ore moisture; coefficients are proportional. C2ality, with the proportionality coefficient C2 being adjusted in proportion to the measured average for a given period, the deviation of the fraction of a given size from the measured in the discharge. given value. The drawing shows the functional scheme of the system, implementing the proposed method. The system contains a drum-type ball mill 1, a spiral classifier 2, a weighing ore metering device 3, a hyt water flow regulator 4 supplied to the mill, a wedge oil pressure gauge sensor 5 in the thrust bearing, an instrument b for measuring the content of the solid phase fraction of a given size in the sink, samplers 7 and 8 for laboratory analysis of ore by size and moisture content B, adder 9, corrector 10 assignments for ore consumption, adder 11, computing unit 12, keys 13-15, somum matrix 16, regulator 17 for controlling water consumption sifikator, a smoothing filter 18 and the equalizer units 10, 12 and 19 are implemented by the microprocessor electronics 60. The output of the mill 1 is connected to the input of the classifier 2, one of the outputs of which Q is connected to the entrance of the mill, and the second output is a drain. The second input of the classifier 2 soy dinene with the output fl. regulator 17, the input of which is connected to the output of the adder 16. One of the inputs of the adder 16 is connected to the output of the device to the second input serves the specified value K2 of the content of the established solid fraction in discharge Sj of the classifier 2. The first input of the mill 1 is connected to the output of & 2 regulator 4, to the first input of which I apply water flow. The second input of regulator 4 is connected to the output of the adder 11. The input of the adder 11 is connected to the output of the block 12. To the first input of the block 12, the content of the established fraction of the solid phase in the drain is supplied . The second and third model inputs through keys 1 and 14 are connected to. the outputs of the samplers 7 and 8.. The second input of the mill is connected to the output of the dispenser 3, the first of the inputs of which serves the flow of ore A, and the second is connected to the output of the sum of the matrix 11. The output of the sensor 5 is connected to the first input of the adder 9, the second. the inlet of which is supplied with the set value P of the oil wedge pressure The output of the adder is connected to the input of the corrector 10, the output of which is connected to the second input of the adder 11. The output of the adder 16 is connected to the input of the filter 18, the output of which is connected via the switch 15 to the input of the corrector 19. The output A corrector 19 is connected to one of the inputs of block 12. The method is carried out as follows. Results of analyzes for grain size and moisture. In ores, taken through samplers 7 and 8, are fed to the outputs of the computational unit 12. However, they also supply the specified content of the determined solid matter fraction in the discharge of the classifier. In the model, the optimal value of the ore consumption is calculated by the formula. Q (SS) (de C and Cj are the coefficients found empirically; .K. Is the content of pellets of a given size in the ore. Sensor 5 measures the pressure P of the mass wedge and in the adder 9 compares it with P. The error signal equal to the difference Pj-Pr is fed to the input of the corrector 10, where a correction signal is generated either with the other 2 where Cj and Sc are the coefficients found by the test. In the adder 11, the signals Q and q Q are produced and the task is generated 0. For ore dispenser 3. Simultaneously, the same signal serves as a reference for the regulator. 4. Dispenser 3 doses their ore to the mill, and regulator 4 directs the flow of water to the mill, f gDe H®1 (3) where C 5 is the ratio between the ore and water consumption supplied to the mill and found by operation. The pulp from mill 1 is fed to the inlet of classifier 2. Sands Ee from the classifier are fed to the inlet of the mill, and discharge Qj is the finished product.The content of the fixed fraction of the solid phase in the drain is measured by instrument 6 and the signal K. proportional to the measured content is fed to the input adder 1.6, in which it is compared with Adan K2. The 4K error signal is supplied. To the input of the regulator 17, which controls the water flow of the SC in the classifier a "4 (Oj + CbaK + C7 dK-dl-t, (4) where 614 (0) is the initial water consumption in the classifier; C and C coefficients found experimentally. The mismatch of the DCs simultaneously serves the filter 18, which forms the mean deviation value for a given period. K y-AKcit, (5)

where T is the specified smoothing period.

At intervals of time equal to T close the key 15 and LC serves to the input of the equalizer 19, which adjusts the coefficient C2

t

(6) CgSCjlOJ + CgAK + CgLlColttC d K / at,

where C2 (0) is the initial value of the coefficient Cg;

 - coefficients found by experiment. The consumption of ore fl in the mill can vary within the range of 70-150 t / h. The flow rate of water 2 supplied to the ground ™ varies within 35-75 tons / h. The flow rate of water supplied to the mill, sect etc is within 35-75 tons / h The moisture content of the ore varies within. The pressure setpoint. RPH is in the range of 25-75 kg / cm. The preset value of fractions less than 0.16 mm in the discharge can be in units 18–22. The flow rate of water supplied to the classifier is 70–120 ton / h. The predetermined period (correlation T is within, from 1 to 4 hours. The period of control of moisture and size of ore is determined by the production conditions and can vary from 4 to 8 hours.

Primer p. Initial data; 21%, B 0.10, K - the content in the ore of granules with a size greater than 25 mm is 13%, C 5.4, 0 (0) 1.4, ER 30 kg / cm, LR O, Co 2, C 0, 5, Cs 0.5, (SC (0) 100 t / h, Cg 2, Cf-0.5 T 1 h, DK 0, C8-0.1, C9-0.02, C 0.

The order of action of the indicated system realizing the proposed method for this particular case is as follows.

With the help of laboratory analysis, the content of K is measured, in the ore of fractions with a particle size of more than 25 mm and the moisture content of B of ore K 13%, and B 0.1. In block 12, the following is calculated: is calculated by the formula (1) 5 ore consumption and (5.413 + -1.4 21) (1-0.1) 116.6 t / h. The sensor 5 measures the pressure P of the oil wedge in the bearing P 29 kg / cm. In the adder 9, the E is the agreement of the LR; 10 4P 30-29: 1 kg / cm. In the corrector 10, according to the formula (2), there are Dw: yes (2.0 Yu, 5) (1 + 0) 2.5 t / h. In adder 11, determines the total QT reference for ore consumption, 6 + 2.5 119.1 t / h.

Dispenser 3, in accordance with task 1, directs the flow of ore 0. into the mill. The ratio controller 4 directs the flow of "2 V ® 0.5-119.1 to 59.5 t / h to the mill. The device 6 measures the content of the K fraction of the solid phase in the discharge, less than 0.16 mm, K-20%. In the adder 16 there is a mismatch LK 21% 20% «1%. The regulator 17 doses the water flow 84 classifier according to the formula (4) f (2) l + (- 0.5) i Jtd + O) 97.5 t / h. On this loop control is terminated.

Suppose that for a set period of time T 1 h in block 18, it will be found on formula (5) that LC is 0.5%. Then in the correction formula 19 by the formula (6) the new value of the coefficient C 2 C2 1.4 + (- 0.1) 0.5 + (- 0.02) 0.5 1г34;

This is where the control loop ends.

Thus, in the proposed method, it is achieved that the control accuracy is improved by maintaining a predetermined fractional composition of the solid phase in the discharge.

Claims (1)

METHOD FOR AUTOMATIC CONTROL OF THE WET ORE GRINDING PROCESS IN A BALL MILL, including the change in the pressure of the oil wedge in the discharge bearing, the change in the ore flow is proportional to the deviation of the pressure of the oil wedge from the set value and maintaining the specified ratio between the flow of ore and water to the mill by affecting the mill water flow rate characterized in that, in order to improve control accuracy by maintaining the specified fractional composition of the solid phase in olive, the content in willow of the classifier of the fraction of the given fineness, the average deviation of the measured content from the set value over a set period, humidity and fractional composition of the ore are periodically measured, the water flow into the classifier is directly proportional to the deviation of the measured content of the fraction of the given fineness from the set value, and when the ore flow changes its consumption by the value calculated by the formula where is the ore consumption; Κ _Ί - measured fraction content of a given size RUDE; ' Kj - established content | fractions of a given size, solid phase in the discharge of class-I syphifier; I 8 measured ore moisture; ^with 2 “proportionality coefficients, and the proportionality coefficient C ₂ corrects, in proportion to the measured average over a set period, the deviation of the content measured in the discharge. The fraction of a given particle size from a given value. 0996601 “P V