Feed density control in rod drum mill at sylvinite ore milling stage

High energy input of milling decreases economic efficiency of ore pretreatment. It is of current concern to improve control over milling of sylvinite ore in production of potassium fertilizer at an annual output of millions of tons. The efficient control can reduce the energy input of the process and increases the quality of the end product at relatively low investment. The improved control of milling ore of potassium is achieved owing to the use of additional information from existing gauges and from the authorial dynamic model of the milling process. The wet milling technology is described. The conservative dynamic model is built using the customary representation of the process flow stages as independent links of a complex object of control – a salt rod drum mill at EuroChem Usolskiy, Perm Krai. At the stage of sylvinite ore milling down to flotation size, the control of the mill in its interaction with the high-performance sieves enables a considerable decrease in over-milling which leads to the loss of a useful component. It is proposed to support the invariant loop of control of the pulp density by information on the disturbance–mass flow of recycle stock. The simulation model is implemented in MATLAB Simulink to calculate efficiency of the proposed reconstruction of the automatic control system. The flow density control at the mill outlet is assessed using the existing measurement system with the proportional regulator and using the proposed combination system. The research shows that the inclusion of the disturbance into the process control and the disturbance action compensation enables essential improvement of the control quality as compared with the manual or proportional control. Accordingly, the proposed re-organization of the automated control system can be recommended for the introduction into industry. The proposed information approaches to the control improvement are usable both in other processes of ore pretreatment and in milling other ore minerals.

Zatonskiy A. V., Bekker V. F., Saramaga Yu. O. Feed density control in rod drum mill at sylvinite ore milling stage. MIAB. Mining Inf. Anal. Bull. 2024;(8):125-140. [In Russ]. DOI: 10.25018/0236_1493_2024_8_0_125.

A.V. Zatonskiy¹, Dr. Sci. (Eng.), Professor, Head of Chair, e-mail: zxenon@narod.ru,
V.F. Bekker¹, Cand. Sci. (Eng.), Professor, Professor, e-mail: bekker@bf.pstu.ru,
Yu.O. Saramaga¹, Student, e-mail: ysaramaga@mail.ru,
¹ Perm National Research Polytechnic University, Berezniki Branch, Berezniki, Russia.

A.V. Zatonskiy, e-mail: zxenon@narod.ru.

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