An experienced SAG mill operator or metallurgist can recognize the trends in operating conditions associated with various operating states that may impact SAG mill grinding performance.

"AG-pebble and AG-ball milling circuits are increasingly favored for reductions in media consumption, facilitating lower OPEX and reduced carbon intensity," agreed Nick Green, vice president – Horizontal Mills at .

A SAG (Semi-Autogenous Grinding) mill is a giant rotating cylinder filled with grinding media and the ore being reduced. As the mill rotates, the grinding media lifts and the impact crushes the feed material. SAG mill control refers to the practice of managing the mill load, which is the amount of material inside the mill at any given time.

The single stage SAG/AG milling option is . × ... 2 contains operating scenarios and appropriate actions that should be taken by the operators or control systems to control a single stage AG or SAG mill. The guide should form the basis of any control philosophy. Table 2 - Generic Operating Guide SCENARIO ACTION Mill Load Power Draw Circulating ...

• Control • Mill Design . 3.1 Circuit Design . Ag/sag milling has now been accepted to the point where it is the favoured choice in nearly all new projects. For many years, however, the ...

Prior to embarking on the development of any type of high level control strategy, a series of tests is required to determine the nature of the relationships between SAG mill …

PDF | On Jan 1, 2001, S. Morrell and others published Influence of feed size on AG / SAG mill performance | Find, read and cite all the research you need on ResearchGate

3 SAG mill (8 – 15% ball charge) Variable competency ore 4 High ball charge SAG mill (15 to 25% ball charge) Incompetent ore 5 Low ball charge SAG mill, high mill speed. (4% ball charge, 90% Nc) A cross between AG and SAG for competent, abrasive ores. As typically operated in RSA. 6 SAG mill (configurations 3, and 5 ) with recycle crusher

related to SAG mill performance and control is the power draw of the mill. Much attention has been given to predicting the power draw of the mill (Morrell, 1996a, Morrell, 1996b, Morrell, 2004 ...

As primary grinding units which receive feed directly from crushers, industrial AG/SAG mills are difficult to control and stabilise owing to the variability of the feed ore characteristics in terms of hardness (work index), ... Due to the unfriendly environment of AG/SAG mill operations, as well as the opaque nature of the mill shells, direct ...

The operation of AG/SAG mills is sensitive to mill filling, therefore developing grindcurves to relate mill filling to performance indicators such as throughput, power draw, and product size can assist in achieving optimal mill operations. The ... Comminution Grinding SAG milling Process control a b s t r a c t The operation of AG/SAG mills is ...

Add-ons for SAG and AG mills. Mill liners - Armour™ mill liners increase uptime and improve grinding efficiency; LoadIQ™ – A smart tool to optimise AG and SAG mill loading to increase throughput by 3 – 6%; Smart liner package – Extend liner life and reduce power consumption with a specialist package of lifecycle services

Control of -SemiAutogenous Grinding(SAG) mill weight is an example of an important process that exhibits many of these aspects. Maintaining the SAG mill weight at the optimum value is critical for achieving maximum grind rate efficiency and mill production (Powell, M.S., van der Westhuizen, A.P., & Mainza, A.N. 2009).

The instrumentation installed on a SAG mill is integral to control. For example, the mill load and noise sensors are instruments that provide essential information for an optimized SAG mill operation. Insufficient understanding of the ore characteristics and feed composition can result in an ineffective SAG mill operation.

The design of large mills has become increasingly more complicated as the size has increased and there is little doubt that without sophisticated design procedures such as the use of the Finite Element method the required factors of safety would make large mills prohibitively expensive. In the past the design of small mills, up …See more on 911metallurgist

AG MILL or SAG MILL introduction. AG MILL(autogenous grinder) or SAG MILL(semi-autogenous grinder), also known as No media mill,, which works principle same as ball mill, the difference is even greater its cylinder diameter, without a ball or any other grinding media, the use of the cylinder body is pulverized material itself as a medium in the cylinder body continuously and …

Mill Sizing: After laboratory and pilot plant testing confirm the feasibility of autogenous or semi-autogenous grinding, it can be used to establish the exact grinding circuit and mill size.In the pilot plant tests, the tare power of …

2. Background. The SAG grinding process has been modeled by various authors, either generating explanatory models of the grinding process, with the aim of modeling, simulating, and optimizing the individual process, as well as integrating it into aggregate processes, such as the mine-to-mill (M2M) paradigm, a practice that has generated the …

An Expert System for Control of a Sag/Ball Mill Circuit. e) AG/SAG Mill Theory - Text and graphics explaining grinding definitions, the fundamentals of AG and SAG mills, mill control strategies, techniques for handling problems with overviscous pulps and effects of variation of mill speed, ball load and total mill charge on throughput and ...

Difference Between Sag Mill vs Ball Mill - mech4study. 1. SAG mill is the primary tool for grinding. SAG mill is used before the other mills. Ball mill is a secondary, and it is used after the SAG mill. 2. SAG mill breaks the raw material into pieces for the further grinding.

The dynamic model of an AG/SAG mill includes several interlinked sub-process modules, and these modules can be updated individually. As shown in Fig. 1, the mill is divided into n sections, where m is the section number and q is the transported material. All sections have the same length, and each section contains a dataset of particle information at any simulating …

With a constant mill weight/power draw control strategy this would result in a decrease in throughput. It is important to stress that this response is similar to that shown in Figure 2 and relates to sag mill operation. ... As all exprimary crusher ag/sag mill feed size distributions are the result of how in-situ rock has been blasted and ...

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 …

Feeding AG/SAG mills with secondary crusher products changes the breakage behaviour and classification of the ore in the mill when compared with mills fed with primary crusher products. This requires changes to the ball and total mill filling levels, process control, shell liners and discharge system designs.

In a large-scale operation, feed ores are introduced into the AG/SAG mill in a continuous mode at a given flow rate to replace the discharging slurry. Nonetheless, the variations in the feed characteristics, typically hardness and size distribution, could cause sudden disruption to the mill operation. This would be challenging to detect in practice, owing to the hostile …

Pilot scale testing is essential for designing AG milling circuits. Photo: . Alternatives to SAG mills: Going fully autogenous SAG mill-based flowsheets typically have high greenhouse emissions (GHG) associated with …

AG/SAG mill is inefficient in grinding particles of a certain size, typically in the range of 25-55 mm, i.e., pebbles. Therefore, cone crushers are often used as pebble crushers and integrated into AG/SAG mill circuits to break the critical size particles that accumulate in the mill and to increase the performance of the primary grinding circuits.

This study supports the use of mill acoustic sensing technique to understand different grinding conditions in AG/SAG mills for improved and continuous process monitoring, …

"Hardening of the ore over time thus creates less impact on throughput in a VRM compared to an AG/SAG mill and can be easily compensated for by increasing grinding pressure. The Loesche VRM, for example, is equipped with a self-adjusting process control system that automatically adjusts the system to changes in ore hardness and mineral ...