SU915961A1 - Method of automatic control of grinding process in ball mill with introducing surface-active substance - Google Patents

Description

The invention relates to methods for automatic control of the grinding process in ball tube mills with the introduction of surface-active substances (surfactants). And can be used in chemical, ore-dressing, cement and other industries that use fine grinding of materials.

A known method of controlling the grinding process in a ball mill, which includes the introduction of surfactants depending on the filling level of the first chamber of the mill with the material [1].

The disadvantage of this method is that the concentration of surfactant in the comminuted material remains constant, moreover, it does not take into account the fact that when changing some properties of the comminuted material, the specified surfactant concentration becomes excessive. Increased surfactant concentration in the material leads to nezapla2

change in the quality of the finished product.

The closest to the present invention is a method of automatic control of the grinding process in a ball mill with the introduction of surfactants, including a change in the consumption of surfactants proportional to the level of filling the mill with material and extreme control of the concentration of surfactants in the grinded material depending on the performance and power consumed by the mill drive. In this method, an extreme search for such a surfactant concentration in the comminuted material is carried out, at which the specific electric energy costs for grinding I 2 are minimized]

The disadvantage of this method is that it does not take into account the possibility of changing the properties of the finished cement when the surfactant concentration in the grinded material is excessive. For example, with a high content of surfactant

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plasticized cement can be obtained, although this mark is not provided by the technological map of the enterprise.

The purpose of the invention is to improve the quality of management.

This goal is achieved by the fact that in the method of automatic control of the grinding process in a ball mill with the introduction of a surfactant, including a change in the flow rate of surfactant is proportional to the filling level of the mill with material and the extreme regulation of ciento. depending on the capacity and power consumed by the mill drive, the surfactant in the grinded material additionally measures the fluidity of the finished product, compares it with a predetermined value, and if the fluidity exceeds a predetermined value, the extreme regulation of the surfactant concentration ceases and decreases in proportion to the deviation value measured yield value from a given.

The drawing shows the block diagram of the device that implements this method.

The device contains a mill 1, a sensor 2, the degree of filling of the first chamber of the mill with material, a surfactant flow rate controller 3, a power sensor 4, a capacity sensor 5, a division unit 6, an extreme surfactant concentration controller 7 in the material to be ground, an actuator of the SAA flow regulator 8, a sensor 9 the yield strength of the finished product, the comparison unit 10, the multiplication unit 11, the logic device 12, the switching unit 13 and the concentration calculation unit 14 with a deviation of the yield strength of the finished product from the specified value.

The method is implemented as follows.

The material is ground in the mill 1. The consumption of surfactant in the mill is determined by the regulator 3, depending on the degree of filling of the mill, measured by sensor 2, and a predetermined concentration of surfactant in the grinded material. The consumption of surfactant is carried out through the executive mechanism of the regulatory body 8. To determine the concentration of surfactant in. the material to be ground is measured at 35

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45

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the main drive of the mill with the help of sensor 4 and the capacity of the unit for the finished product using sensor 5. Using ₅ units of division 6, calculate the specific electricity consumption for grinding, and then use an extreme regulator 7 to search for such a surfactant concentration Real electricity costs would be minimal.

Assume that at some point in time the concentration of surfactant in the grinding material is optimal in the sense of 15 minimum energy consumption for grinding. While the fluidity of the finished product, measured by the sensor 9,

, does not exceed the specified value of those ·; a pileiness that is determined by

„Block 10 comparison. Next mo2i

ment time properties of the crushed material · changed so that the fluidity of the final product increased, the predetermined values ₂₅ of flow has been exceeded. (For example, a range of extreme concentration adjusting technology modified lignosulfonates (LSTM) in the material being ground, giving ₃₀ yn intensification of grinding process is in the range 0,0-- 0.26%. In a cement plant material Belgorod plasticised cement may be obtained when the content LSTM 0,120,17%, and on the material of the Resurrection Cement Plant at 0.20-0, '22%.

If the specified value is exceeded, continuation of the extreme regulation is not advisable, since it can lead to a change in the grade of cement. Therefore, in case of exceeding the specified yield value, the signal from the comparison unit 10 is fed to the logic device 12 and the multiplication unit 11.

In block 11, the amount of correction of the surfactant concentration determined by the extreme regulator 7 is calculated.

In block 14 receive the corrected signal values of the concentration of surfactants. The surfactant concentration in this unit is reduced in proportion to the deviation of the measured yield from the specified value. The logic device 12 generates commutation switching de- vice 13, ⁵⁵ so that in the case of a normal flow process to the controller 3 receives the job directly from the former $ 0

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of the tremul regulator, and in case the fluidity exceeds the norm, the corrected task from block 14. The amount of surfactant concentration of block 14 is changed so that the grinding process is returned to normal process conditions.

This method allows to improve the quality of management.

Claims (1)

Claim The method of automatic control of the grinding process in a ball mill with the introduction of a surfactant, including a change in the consumption of surfactant is proportional to the level of filling the mill with material and the extreme regulation of the concentration of surfactant in the material to be ground, depending on the capacity and the power consumed by the mill drive, characterized in that, 5 in order to improve the quality of control, they additionally measure the fluidity of the finished product, compare it with a predetermined value if the fluidity exceeds a predetermined value, extreme control of the concentration of a surfactant substance stops and reduces it · is proportional to the deviation of the measured yield value 15 from the given.