SU718168A1 - Method of automatic control of intramill loading in cement mill - Google Patents

Description

/ - current electrostatic precipitators; P - vacuum in the mill; f - degree of loading of the mill; p is the quality of iomol cement.

Depending on the current of the dust-collecting mechanism, it is necessary to change the load of the grinder according to a predetermined schedule (see Fig. 2) in order to optimally conduct the grinding process. The vacuum in the mill is stabilized at an optimum level by acting on the gate of the fan.

The regulator 1 maintains the vacuum in the output neck of the mill 2 by a constant electric signal of the load / first chamber of the mill 2 and the current / electrostatic precipitator 3 using measuring blocks 4 and 5 are fed to the ratio block 6, which produces and outputs a proportional signal of the optimal load to the regulator 7

The current / electrostatic precipitator 3 indirectly indicates the amount of material Qg passing in its interelectrode space, and can be used to judge the amount of material passing from the first chamber to the second chamber of mill 2, while maintaining the negative pressure P in the outlet neck of the mill 2 constant.

As the number of particles moving into the second chamber of mill 2 increases, the amount of dust passing through the electrostatic precipitator 3 also increases, causing a decrease in the current in it.

By reducing the amount of material passing into the second chamber of mill 2, the amount of dust in electrostatic precipitator 3 decreases, which causes an increase in current in it.

The dependence of the current in the electrostatic precipitator 3 on the passage of material in it is physically explained by the fact that the total current in the interelectrode space of the electrostatic precipitator is equal to the sum of the current alternated by gas ions having a relatively high speed and the current transferred slowly by moving the charged

718168

dust particles. The magnitude of the last current strength is from 1 to 20% of the total current strength in the electrostatic precipitator.

However, since the charged particles are in an electric field for a long time (compared to gas ions), the charges placed on them form a spatial charge, which leads to a decrease in the current strength in the electrostatic precipitator (reduces the number of charges transferred per unit of time between the corona and collecting electrodes).

With an increase in the number of particles in an electric field, the spatial charge increases, causing a decrease in the total current strength.

As the number of particles decreases, the spatial charge decreases, which increases the current in the electrostatic precipitator.

Claims (2)

Invention Formula Method for automatic control of intramill loading in cement the mill, which includes measuring the current of the dust-collecting mechanism, the degree of loading of the mill and the dilution in the mill and changing the degree of loading, characterized in that, in order to improve the performance of the mill at a given value for the fineness of grinding, they also stabilize the depression of the intramillary space by influencing the fan gate and set the ratio between the degree of loading of the mill and the current of the dust-collecting mechanism, and the change in the degree of loading is carried out based on maintaining a predetermined ratio between the degree of loading of the mill and YOKOM dust collecting mechanism. Sources of information (information taken into account during the examination 1. USSR author's certificate No. 449742, class B 02C 25/00, 1973. 2. Issues of automation of dust systems with spherical drum mills, ORGRES, Energie, 1965 p. 25-41.