sag mill control

The ROM SAG mill circuit—a brief description. The typical ROM SAG mill circuit is depicted in Figure 1. The circuit is usually closed with either a screen or, more commonly, a cyclone for product size classification. The focus of control can be divided into two parts, viz. the mill and the cyclone.

Effective SAG mill control will maximise throughput, minimise damage to mill internals (liners and lifters) and contribute significantly to achieving maximum recovery in flotation. Well designed and implemented SAG control will payback in weeks not years. SAG mill control is essentially the stabilisation of mill load (and/or power) and density

Continuously improve, identify and test the controller – the overall objective is to stabilize SAG mill control for high ore variability. A stable SAG mill performance enables …

Over the past seven years, there have been approximately 40 projects globally working on installations of energy-efficient SER drives. With our SAG mill running at 65.4% critical speed (mill @ 8.7 ...

A SAG mill, or semi-autogenous grinding mill, is a type of machine used in mining and mineral processing operations. It uses the crushing and grinding action of rocks to reduce materials such as copper ore into smaller pieces for further processing. Unlike traditional mills that rely on steel balls or other media to break down materials, SAG ...

An autogenous circuit is difficult to control final grind. Autogenous plus crusher. This circuit was difficult to control and resulted in low tonnage. ... Semi-autogenous plus ball mill has been the "work horse" of mills. SAG vs Ball Mill Advantages . AG & SAG Mill Grinding Compared – Which is Best. Grinding rods and balls can be …

SAG mill control fundamentally means managing the load in the mill by adjusting the feed rate of ore to the mill and/or manipulating the rotational speed of the mill. The best way …

Rocky DEM, a software tool developed by Brazilian company Engineering Simulation and Scientific Software (ESSS), predicts SAG mill liner wear over time and helps engineers adjust conditions for mill operations by …

The typical application of the adaptive model-based predictive controller for SAG mills is for control of the mill load. In these cases, mill load was inferred either from a direct weight measurement or from bearing oil pressure. Figure 2 gives a diagram showing the SAG Mill and the load control strategy.

In a SAG mill, the speed control system is a nonlinear and strongly coupled multivariable system. The proportional integral (PI) vector control method is used in the mill control system . The PI vector control method cannot meet the requirements of high-performance control when the mill speed control system is subjected to external …

The accurate control of feeders in Semi-Autogenous Grinding (SAG) mills plays an important role for obtaining good operational results. This paper presents the design of a Smith predictor for MISO systems, representing a set of feeders in a SAG plant. The design considers the special characteristics of the application, as well as issues like ...

To stabilize and optimize the operation, ramp up production and prevent damages to the SAG mill liners, Cía. Minera Antapaccay contracted with FL to implement …

controls downwards; so without the advanced regulatory control layer, the comprehensive plant automation strategy cannot be properly built. In this paper, an industrially proven …

The biggest characteristic of the sag mill is that the crushing ratio is large. The particle size of the materials to be ground is 300 ~ 400mm, sometimes even larger, and the minimum particle size of the materials to be discharged can reach 0.1 mm. The calculation shows that the crushing ratio can reach 3000 ~ 4000, while the ball mill's ...

(EGL) SAG mill driven by a 24,000 kW gearless drive. The SAG mill feeds two FL ball mills each 26 ft. in diameter × 40 ft. long (EGL), each driven by a 16,400 kW drive. The SAG mill is one of the largest volumetric capacity SAG mills in the world and represented the first 40 ft. SAG mill in Peru (Garcia & Villanueva, 2013 [1]).

The mill operator then needs some way of balancing the distribution of this critical sized material between the primary and secondary mill as an onstream operating control. This would allow the operator to adjust the workload between the primary and secondary mill as the ore changes so one will not be overloaded and the other underfed.

The simplest controller would employ feedback (FB) only control by adjusting the SAG mill feed rate to maintain the SAG mill power draw at its set-point value. As with any feedback controller, such a system can only take action after a disturbance has affected the process and caused a measurable deviation from the set-point.

Acoustic emissions monitoring could aid in-mill energy-efficient operation. Towards the development of an improved and more efficient online monitoring system in an industrial AG/SAG grinding mill, the present study employs a laboratory-based AG/SAG mill and acoustic sensor to investigate the acoustic characteristics of different mill …

index by using values from an operating circuit. Its value is only valid at the stated SAG product size. • Transfer size (T80) is the term used to describe the SAG mill product that is sent to the ball mill. For peak performance and balancing the power available in the SAG mill and ball mill, the transfer size must be measured and controlled.

In order to obtain the optimal operation parameters of a SAG mill, in this paper, the discrete element method (DEM) is used to simulate the breakage process of the particles by controlling three ...

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 output quality.

2.4. Multivariable predictive control. In the present work, a three-input-three-output scheme of control was performed. The total water feed to the mill (the feed water flow rate was added to the dilution water flow rate, so they could be specified separately, but for the SAG mill model, the total water content was the variable of interest), the fresh ore …

AG and SAG mills are now the primary unit operation for the majority of large grinding circuits, and form the basis for a variety of circuit configurations. SAG circuits are common in the industry based on: High single-line capacities (leading to capital efficiency) The ability to mill a broad range of ore types in various …. Read more.

Recent developments in low power wireless and Digital Signal Processing (DSP) technologies have given rise to a new system that can monitor vibrations in real-time on the rotating surface of SAG, AG, and Ball mills. Specifically designed for the SAG mill, a new device is presented that digitizes and processes vibration from three key points on the …

SAG mill control requires managing the load in the mill by adjusting the feed rate of ore to the mill and/or manipulating the rotational speed of the mill. The load cells are calibrated to measure ...

feed and recycle crusher operation have resulted in the evolution of. control of SAG and AG mills to utilis e new advanced control techniques. These techniques are necessary to maintain stability ...

When SAG mill liner bolts loosen, break or stretch beyond limits, liner impairment and degraded performance are generally next on the agenda, followed by mill stoppage for repair or replacement. ... McLellan …

PRESS RELEASE: FL has launched SAGwise, a sensory and process optimisation system designed to optimise the use of the three main consumables in SAG milling: power, media and liners. The SAGwise total process control system can reduce energy consumption by up to 6%. This is a significant reduction considering that, …

SAG Mill Control Strategy using Profit Controller "ProfitSAG" applications have been implemented using Honeywell technology called "Profit ControllerTM"; this is a Multivariable Predictive Control algorithm based on models, also known as RMPCT (Robust Multivariable Predictive Control Technology). As its name points out, this …

SAG / Ball Mill Monitoring Condition Monitoring to Ensure Reliability for Critical Grinding Equipment in Mining Today's mining operations must keep crucial milling assets online and running optimally, but variations in ore particle size, feed rate and moisture content, can lead to plugging, high vibration and machine bearing wear, and ...