SU995882A1 - Method of automatic control of single stage wet disintegration cycle - Google Patents

Description

(3) AUTOMATIC CONTROL METHOD FOR SINGLE-WIDE CRUSHING SINGLE-CYCLE

one

The invention relates to the automatic control of technological processes of enrichment, and more precisely to methods of automatic control of the process of wet grinding, and can be used in enrichment (|) abricas of nonferrous and ferrous metallurgy, having similar cycles of processing raw materials.

A known method of automatic control of a single-stage wet grinding cycle, including stabilizing the flow rate of the original ore into the mill, the classifier discharge size and ore-water ratio, measuring the amount of water supplied to the classifier and classifier sand size, correcting the flow rate of the original ore to the mill according to the change in water quantity, fed into the classifier, and the size of the sand of the classifier, and the correction of water flow in the mill according to a change in the size of the sand of the classifier tOLost A known method is the impossibility of attaining the maximum productivity of the finished product of a given class with changing physicomechanical characteristics of the raw material. This is due to the fact that, when regulated by a known method, it is not supported.

10, the optimum pulp density in the mill lives, which corresponds to pumping the processed raw material, because the size of the sand of the classifier used to correct the consumption of ore and water in the mill does not sufficiently characterize the change, such as the original ore, due to the fact that hk is on average constant, and only their volume changes, i.e. the circulating cycle load, and the existing means of controlling the size of the sand of the classifier are imperfect, give a large error. As a result, the corrective action cannot bring the shredding unit to the area of optimal modes, and in this connection there are significant fluctuations in the technological parameters and the low quality of the control of the grinding process. The closest to the present invention is a method for automatic control of a single-stage wet grinding cycle, including controlling ore consumption and water consumption in a mill, measuring the size of a grinding product in a ball mill unloading and classifier discharge, adjusting the size of a grinding product in a classifier discharge with a value sign correction deviations from the specified size of the grinding product in the unloading of the mill and the discharge of the classifier and the correction of the adjustable values of ore consumption and water into the mill. In the known method, the ore consumption control is carried out with a correction by the sign of the magnitude of the deviation from the specified size of the product of the reduction in the discharge of the mill | 2 j The disadvantage of the known method is the impossibility of achieving the maximum possible productivity of the finished product due to the presence of fluctuations in the size of products in the unloading of the mill and the classifier, caused by neglecting the varying time of the material in the mill depending on the properties of the processed material (size, grindability) and from the grinding mode (total feed of the mill by ore and sand of the classifier, the ratio of the values of ore consumption, sands and water in the mill, etc.). The purpose of the invention is to improve the quality of control by eliminating the occurrence of accidental fluctuations of the technological grinding process. The goal is achieved in that according to the method of automatic control of a single-stage wet grinding cycle, including controlling the ore consumption and water consumption in the mill, measuring the size of the grinding product in the discharge of the mill and discharge of the classifier, adjusting the size of the grinding product in the discharge of the classifier with a correction of the deviation value from the specified size of the grinding product in the unloading of the mill and the discharge of the classifier, and the correction of the controlled values of the ore and water consumption in m In addition, the water consumption in the classifier discharge is measured, the circulating load is measured by the measured ore consumption, the discharge flow of the classifier, the size of the grinding products in the mill discharge and the discharge of the classifier, the time spent for the material in the mill is determined by the cost of ore and water into the mill, the flow rate of water into the discharge of the classifier, the magnitude of the circulating load and the size of the grind products in the discharge of the mill and the discharge of the classifier, predict the size of the and the grinding product in the mill discharge according to the ore flow rate, circulating load, water consumption in the mill and material residence time in the mill, and the ore consumption is corrected according to the circulating load, and the water flow correction in the mill is proportional to the difference between the set and predicted values of the size of the grinding product in the discharge of the mill. The drawing shows a diagram of the device that implements the proposed method. The scheme includes a system for stabilizing the flow rate of the original ore in the mill, KOTOpain contains a weight gauge 1 for ore consumption, a secondary device 2, a regulating device 3, a control unit k for the thyristor converter 5 of the drive engine 6 for the feeder consisting of a size sensor 7, a secondary device 8, a regulating device 9, an actuator 10 of a valve 11; a system for regulating the flow of water into the mill, which contains the flow meter 12, the secondary device 13 for the flow of water into the mill, the regulating device 1, the actuator 15, the valve 16; The contour of correction of the size of the grinding product in the discharge of the classifier, which contains the sensor 17 of the mill unloading size, the secondary device 18, the comparison and adjustment unit 19, the correction change actuator 20, the setting unit 21 of the stabilization system in the discharge of the classifier correction circuit, water and ore into the mill, which includes the flow meter 22 of the water flow into the classifier discharge, the secondary device 23, the setting unit 2 of the mill discharge, the computing unit 25, with access to the controllers 3 and 14.

The grinding unit of a single-stage wet-grinding cycle consists of a granule 26 operating in a closed cycle with a classifier 27. Both mechanical single-or double-spiral classifiers and hydrocyclones can be used as a classification apparatus.

According to the method, the wet grinding process is controlled by affecting the ore and water consumption in the ball mill and the water flow rate into the classifier, as follows.

Optimal filling and pulp density in the mill is maintained by adjusting the flow of water and ore to the mill with appropriate stabilization systems.

When the physicomechanical properties of the original ore change, for example, when switching from ore to soft, the content of the finished product in the discharge of the classifier and the productivity of the finished product increase. The signal of the current size of the classifier drain. The sensor 7 of the size through the secondary device 8 is fed to the regulator 9, which changes the water flow in the classifier through the actuator 10 and the valve 11 in the classifier to restore the specified size.

Due to the change in the flow rate of water into the drain of the classifier, the pulp volume and the circulating load change, and their change is proportional to the change in the flow rate of water to the drain of the classifier.

The yield of the finished class in the discharge of the classifier and, consequently, the productivity of the cycle for the finished product depends on the size of the crushed product in the unloading of a ball mill, which, in turn, depends on the properties of the processed material and the mode of grinding.

When the textural, structural and physicomechanical properties of the starting material change, for example, in the direction of increasing the initial size and strength, the weight consumption of the finished class in the unloading of the mill and at the discharge of the classifier decreases, it leads to an increase in the average size of the grinding product in the ball mill, in its unloading, therefore, to an increase in the circulating load and an increase in the difference in the roundness of the material on the discharge of the mill and the classifier.

In proportion to the magnitude of this difference, the setting of the classifier’s particle size stabilization system is changed in order to prevent the emergency blockage of the mill.

In order to introduce a timely advance correction for changes in the circulating load, the computing unit 25 calculates the magnitude of the circulating load from the signals from the devices 2.8, 18 and 23 using the expression, for example,

S-ci, aaW, -a,) Q a mi rej ± M ,,

circulating load;

S where

Q ore consumption in the mill; w consumption: | water in the discharge of the classifier,

d, and d are the size of the product in the discharge of the mill and the discharge of the classifier, the coefficients of the equation.

L 4 gressii.

The signal of the circulating load is determined taking into account the cycle time delay, and is fed from the first output of block 25 to controller 3, which realizes maintaining the specified amount of sand and initial ore by changing the drive drive 6 through the blocks and 5.

In order to reduce the dispersion of fluctuations in the size of the product in the discharge of the mill and the classifier and to adjust the pulp density in the mill to the type of ore processed, block 25 calculates the residence time of the material in the mill using an experimental expression, for example,

l-10o + - (ti + -b.

Claims (2)

) 4l, (1 where b -b- are the coefficients of the regression equation; T is the material residence time in the mill; and W is the flow rate of water to the mill. I. Determine the size of the grinding product S mill drain at the time of prediction that is from the amount of time the material has been in the mill, the difference between the predicted value of the particle size and the target value is determined, and the flow of water into the mill is adjusted by the magnitude of this difference, and if the predicted particle size is greater than the specified one, the water flow into the mill is reduced, and if less, it is increased. size value d determined by eksperimentalnrstatisticheskoy depending, for example, view .A.g z + C, rb) "1 - o.; - 5 (/ - m-5 v where C-C is the regression equation coefficients. The type of expressions (.1) and (3); And the regression coefficients are periodically refined during the setup process. And the settings on the active object. This is done output of the grinding complex to the maximum possible maintenance mode: for this type of ore productivity, and the fluctuations of the output indicators of the mill and classifier are reduced. All the correction signals come with coefficients that are determined empirically and increase the percentage of corrective measures Size Control The grinding process maintains the optimum performance of the grinding unit for the original feed, taking into account the grindability and particle size of the initial product, given the requirements for grain size distribution, by maintaining optimum filling and optimum pulp density in the mill that correspond to the quality of the material being processed. Improved quality process control due to an earlier consideration of the reaction of the circulating load on the disturbance, according to the initial power th. The yield of the finished product increases by 0.22%, the fluctuations of the grain-size composition noticeably decrease, the annual production of concentrate increases by 0.5, the sweat decreases, the useful component of tailings decreases by 0, the economic effect of implementing the proposed control method is U1 thousand , rub. per year per technology section. The invention The method of automatic control of a single-stage wet grinding cycle, including flow control; ores and water flow into the mill; measuring the size of the grinding product in the mill unloading and kla drain (; sifikator; adjusting the size of the grinding product of the classifier with a correction of the deviation value from the specified the size of the grinding product in the unloading of the mill and the discharge of the classifier, and the correction of the controlled values of ore and water consumption in the mill, so that Then, in order to improve the quality of control by eliminating the occurrence of emergency fluctuations in the grinding process, the water consumption in the classifier discharge is additionally measured, the circulating load is determined from the measured values of ore consumption, the flow rate of the classifier drain, the size of the grinding products in the discharge of the mill and the discharge classifier, determine the time spent by the material in the mill according to the values of ore and water consumption in the mill, water consumption in the discharge of the classifier, the value of the circulating loads and sizes of grinding products in the mill discharge and classifier discharge predict the size of grinding products in the mill discharge according to the ore consumption, circulating load, water consumption in the mill and the time spent in the mill, and the ore consumption is corrected according to the circulating load value , and the correction of water consumption in the mill is carried out in proportion to the difference of the specified and predicted values of the size of the grinding product in the discharge of the mill. Sources of information taken into account in the examination 1. USSR author's certificate number 535101, cl. B 02 C 25/00, 1976. 2. USSR author's certificate W 737013, cl. B 02 C 25/00, 1978 (prototype). H itiC L