the equations governing the motion of steel balls and their impact onto shell liners in industrial semi-autogenous grinding (sag) mills are derived in full details by the authors and are used in order to determine the effective design variables for optimizing the working conditions of the mill and to avoid severe impacts which lead to the breakage of sag mill shell liners. these design variable...

This paper examines the design of comminution circuits and the issues that impact on comminution circuit efficiency. Circuit efficiency is discussed, principally from the perspective of power efficiency. However, operating efficiency, maintenance efficiency, capital expenditure and return on investment are often the key efficiency factors in project development outweighing power efficiency cons...

The equations governing the motion of steel balls and their impact onto shell liners in industrial Semi-Autogenous Grinding (SAG) mills are derived in full details by the authors and are used in order to determine the effective design variables for optimizing the working conditions of the mill and to avoid severe impacts which lead to the breakage of SAG mill shell liners. These design vari...

Semi-Autogenous Grinding mills can be optimized for maximum ore throughput or maximum grinding energy efficiency. In both cases, precise control of the mill weight is critical. Model predictive control provides an additional tool to improve the control of Semi-Autogenous Grinding mills and is often able to reduce process variability beyond the best performance that can be obtained with proporti...

Semiautogenous (SAG) mills for ore grinding are large energy consumption equipments. The SAG energy consumption is strongly related to the fill level of the mill. Hence, on-line information of the mill fill level is a relevant state variable to monitor and drive in SAG operations. Unfortunately, due to the prevailing conditions in a SAG mill, it is difficult to measure and represent from first ...

The aim of this research work was to investigate on the ball filling estimation of Miduk semi-autogenous (SAG) Mill via an utilized method. Miduk copper concentrator is located in Kerman Province, Iran, and its size reduction stage includes one gyratory crusher which feeds one SAG mill (9.75 dia.(m)*3.88 length(m)) following two parallel ball mills (5dia.(m)*7lenght(m)). After SAG mill, a tromm...

the aim of this research work was to investigate on the ball filling estimation of miduk semi-autogenous (sag) mill via an utilized method. miduk copper concentrator is located in kerman province, iran, and its size reduction stage includes one gyratory crusher which feeds one sag mill (9.75 dia.(m)*3.88 length(m)) following two parallel ball mills (5dia.(m)*7lenght(m)). after sag mill, a tromm...

The number of lifters of mill shell liners, mill rotation speed, and filling percentage of grinding media are three of the most important parameters influencing the charge behavior and the trajectory of ball motion inside the SAG mills, and consequently, their performance. In this paper, the milling operation of pilot-scale SAG mills using the discrete element method (DEM) is investigated. Firs...

To ensure that these requirements were met, Chinalco and Jacobs Engineering selected ABB as a technology partner and principal supplier of the mine’s electrical and automation equipment. They awarded ABB contracts worth around $120 million to supply three gearless mill drive systems for the semi-autogenous (SAG) mill and two ball mills, a plant-wide electrical solution, and a process automation...

Liner design is becoming an increasingly more important tool for the AG/SAG mill performance optimization. The Gol-E-Gohar iron ore concentration plant uses three 9 m × 2.05 m autogenous mills (AG) in parallel in a dry operation. Due to large variations in feed characteristics and inadequate blending, the performance of AG mills has been lower than the target value. In order to increase the cir...