Process Dynamics of Grinding Circuits and the Use of Automatic Control

CIM Bulletin, 1967

T. C. Crosby Supervising Instrument Engineer, Mining & Metals Division, Bechtel Corporation, Montreal, Que.

Grinding has a marked effect on concentrator recovery and operating cost, and improved operation through a utomatic control can enhance plant performance. The correct application of automatic control can only be accomplished after the basic process variables and their effect on mill operation have been defined. This paper develops a control system for a closed circuit grinding system. Typical control systems, such as tftose for feed, water flow, level and circulating load, are discussed. A method of determining controllability, using the calculated reaction curve technique, is outlined. Various successful automatic grinding control applications are discussed and future possibilities are outlined. Although this paper primarily deals with closed wet grinding• circuits, the principles involved can be readily applied to other processes.