SU733732A1 - Charge control method for closed-cycle mill having hopper and metering arrangement for non-completely ground materials - Google Patents

Description

one

The invention relates to the field of automation of grinding ore in drum mills operating in closed cycles with spiral classifiers at the processing plants of non-ferrous and ferrous metallurgy.

Methods are known for controlling the process of wet grinding of single-stage cycles, based on the use of the noise of Mill 1. .. However, they do not provide the required control efficiency and obtain the required particle size distribution of the grinding products in the case of processing ores with drastically varying quality.

There is a known method of automatic control of wet grinding, including measuring the noise of a mill, the flow of ore and water into the mill and the content of the boundary class in the discharge of the classifier, sound stabilization, the metric parameter of the mill, regulation, the ratio of the ore plant and the size of the discharge classifier 2,

In this method, in order to reduce slag formation, the average value of ore consumption per mill for a certain period of time is periodically memorized, this value is subtracted from its previous value, and. by the magnitude of their difference, a correction is introduced into the ore-water ratio, increasing the flow rate of water at a negative difference and decreasing at a positive one.

The disadvantage of this method

10 is. the impossibility of its realization in the case of the need to obtain a different size of the classifier overflow when processing ore with a variable material composition (variable impregnation).

The aim of the invention is to obtain a predetermined grain-size composition of the products, grinding and reducing sludge formation during

20 processing of ores of various types

chayosti.

This is achieved by the fact that in the method of automatic control of the wet grinding process, including the measurement of the noise of the mill, the consumption of ore and water in the mill and the content of the boundary class in the discharge of the classifier, the stabilization of the sound parameter of the mill,

30 controls the crust ratio of the classifier’s discharge and size, additionally determine the grindability of the ore by calculating the ratio of ore consumption to the boundary grade in the classifier discharge, while adjusting the ore to water ratio increases the flow of water to the mill as the grindability increases and decreases when reducing and adjusting the size of the drain of the classifier, increase the size of its siive with an increase in grindability and decrease at a decrease in grindability,

The method of automatic control of the wet grinding process can be implemented using a device whose scheme is shown in the drawing.

The device contains:

system of automatic loading of the mill according to the sound parameter, which contains the sound sensor. Sensor 1, controller 2, actuator 3, which changes the consumption of ore fed to the mill 4

ore-water ratio system, containing ore flow weight 5, secondary device .6 ore consumption, signal multiplier 7, grain size class content sensor of classifier 8, secondary device 9, signal multiplier 10, computing unit lif calculating ore grindability, sensor 12 the flow rate of water to the mill, the controller 13 and the actuator 14, which changes the flow of water to the mill 4;

a classifier discharge size control system containing a size sensor 8, a secondary device 9, a signal multiplier 10, a controller 15, a setting device 16 and an actuator 17, change ush} 1st water flow into the classifier 18.

Control is performed as follows.

When changing the grindability of ore, the system of automatic loading of the mill according to the sound parameter maintains the noise of the mill at a given level, changing the ore consumption in the mill; The change in the performance of the mill in terms of ore consumption in this case characterizes the change in the quality of ore in one direction or another. In this case, the signal from the weight meter 5 of the ore flow is fed to the secondary device b and then to the breeder 7 signals,. which propagates it to regulator 13 and to

unit 11, from which the correction signal also arrives at the regulator 13./ In the computational unit 11, in addition to the signal from breeder 7, the signal comes from breeder 10, just a fraction of the classifier’s drain. Computing unit 11 generates, according to the algorithm 1.1.1, a signal, proportional ore shredability and outputs it to controllers 13 and 15, Regulator 13 in addition to the existing ore-water ratio increases the water consumption in the mill with an increase in grindability (more melted ore) decreases - with a decrease5 of the Institute of Grindability (harder ore has gone). The regulator 15 by means of the executive mechanism 17 changes the water supply to the classifier 18, increasing its size

0 plum with an increase of crushed-. ti and decrease - while reducing the grindability.

Claims (2)

Invention Formula Method for automatic control of wet grinding process, including measuring the noise of a mill, the consumption of ore and water in the mill and the content of the boundary class in the discharge of the classifier, stabilizing the sound parameter of the mill, controlling the ratio of ore to water and size of the discharge classifier, characterized in that, in order to obtain a predetermined particle size distribution of the grinding products and reduce sludge formation during processing 0 ores of different grindability The ore grindability is determined additionally by calculating the ratio of ore consumption per mill to the content of the boundary class in the discharge f classifier, and when adjusting the ratio of ore to water, increase -. The flow of water into the mill is increased as the grindability increases, and when the classifier drains decreases and when adjusting the grain size, the grain size of the filter decreases as the grindability increases and the grinder decreases as the grindability decreases. Information sources, 5 taken into account in the examination 1, USSR Author's Certificate No. 154470, cl. B 02 C 25/00, 1963, 2. USSR author's certificate number 575130, cl. B 02 C 25/90, 1973 Q (prototype). water