optimization of sag mill circuit

Home optimization of sag mill circuit

Autogenous Grinding (SAG) mill in closed circuit with a hydrocyclone package. The gold ... In this research, an optimization study of Aghdarreh plant grinding circuit performance was done to lower the product particle size (P 80) from 70 Pm to approximately 40 Pm by maintaining current throughput using modeling and simulation approach. After ...


Optimization of mill performance by using online ball and pulp measurements Soon after a stop, a mill is a dangerous place to enter for the personnel tasked with taking measurements or samples. Crash stops are difficult to handle. The mill and all feed streams should be stopped simultaneously but, often, they are stopped around about the same time.


In the first three years of continuous operation, Vale investigated different alternatives for improving the circuit’s performance by investigating operating conditions, mainly focusing on the SAG mill. It was decided to further assess the performance of the comminution circuit as a …


Circuit surveys reported a SAG specific energy of 8.6 kWh/t and ball mill specific energy at 8.0 kWh/t (Dunne et al, 1999 Hart et al, 2001). The T 80 was not given so this was back-calculated to ...


design processing rates of the Cadia Hill SAG mill circuit and that could be easily manipulated were; SAG Mill Load Ball Charge - SAG mill power draw was guaranteed by the vendor at 13% ball charge and 30% total volume to be 20.96MW for the 40 foot diameter SAG mill. In practice this power draw was never achieved I-14 (Dunne et al 2001).


(MPC) is described for a SAG mill circuit in a bauxite processing refinery at Wagerup, Australia (Refs: Gopinath, Mathur et al, 1995 and Le Page, Freeman et al 1996, Luse, Mathur et al 1997). The MPC ... An optimization problem is then set up to minimize the deviation of this predicted output from a


The circuit consists of a 34' x 20' EGL SAG mill, a Raptor 900 pebble crusher and two 24' x 39'6" ball mills. Each mill is equipped with a 2 x 8500HP dual pinion drive system. The plant was designed to process 1585 h mtpof SAG feed. From startup, the mill struggled to meet the required production rates.


By combining with SAG discharge and screening on the SAG discharge screens, top size control to the ball-mill circuit feed is maintained while still unloading the SAG circuit (Mosher et al, 2006). A variant of this method is to direct pebble-crushing circuit product to the ball-mill sump for secondary milling: while convenient, this has the ...


SAG mill in closed circuit with hydro cyclones at Freda Rebecca Gold Mine would affect through put and specific energy consumption using an Excel based milling process simulator developed by Hinde, a comminution specialist who has worked for Mintek for many years.


Generally, the discharge from AG/SAG mills consists of one or both of the following components: slurry (water and finer particles) and pebbles (20-100 mm). Single stage AG/SAG mills have to handle large amounts of slurry as they are generally in closed circuit with classifiers whose circulating loads reach as high as 400-500%.


Haijie Li is doing an industrial Ph.D jointly funded by FL A/S and Danish Innovation Fund, and the Chalmers Rock Processing Systems (CRPS) research group. His research focuses on the modelling and optimization of SAG mill-pebble crusher circuit.


calculations on mass balance on ball mill circuit. Ball mills are used primary for single stage fine grinding, regrinding, and as the second stage in two stage grinding circuits. According to the need of customers, ball mill can be either wet or dry designs.…. Ball Mill. +.


The range of mill sizes and versatile applications allow SAG milling to be accomplished with fewer lines than conventional set-ups. This, in turn, contributes to lower capital and maintenance costs for a SAG mill circuit. Versatile applications . SAG milling extends itself to many applications due to the range of mill sizes available.


Replacements are seldom done to SAG mills due to cost and also the constraints of other circuit equipment. Instead, often additional production lines are added. Also, if the bottleneck is the SAG mill, adding a pebble crusher can provide a small production boost (typically 5 to 10%).


As the Sossego circuit includes the first large diameter semiautogenous mill installed in Brazil, the literature review was largely focused on operating and optimization aspects of such a process ...


Control Of Grinding Mill Circuits Minerallurgy. Even so the steadystate form of this model can be considered as the standard approach to modelling grinding mill circuits a dynamic population balance model for sag grinding mills are found in both amestica et al 1996 and salazar et al 2009 both models make use of a cumulative breakage rate to describe the breakage of ore inside the mill.


SAG Mill power draw models are used in mill design and grinding circuit modelling to predict how muc h pow er wi... [↓ read more ↓] Alex Doll: modelling: A simple estimation method of materials handling specific energy consumption in HPGR circuits


The milling circuit consumes about 50% of the concentrator plant's power demand. ... for monitoring and optimising the performance of SAG mills," he says. "The SAG mill is a key element of ...


Each milling circuit is unique, and as such the goals and most optimal control strategy might differ for individual cases. Process IQ is an expert in implementing control systems for SAG and Ball milling circuits, making use of advanced stabilisation and optimisation strategies developed by Mintek.


2 AG mill + a recycle crusher Competent ore - relatively homogenous (the recycle crusher is used to balance the rate of impact breakage within the circuit) 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.


If the secondary mill is a pebble mill, grinding media for the pebble mill may be removed from the top deck of the screen with any excess returned to the primary mill. In some circuits, the screen over-size is put through a short-head cone crusher …


optimization of the SABC comminution circuit, focusing on the primary (SAG mill) and secondary (ball mill) grinding mills, and estimating the outcomes of changes to circuit operating parameters (e.g., feed rate, mill load, ball charge, etc.).


The SAG mill circuit also includes a single-deck screen and a cone crusher while the ball mill circuit utilizes hydrocyclones. Currently, the grinding circuits are inefficient in achieving the aspired product fineness of xP,80 = 125 μm even at low to normal throughputs (450-600 t/h).


The IntelliSense.io Grinding Circuit Optimization application has been piloted at the Aktogay Plant of JSC "AK Altynalmas". A Digital Process Model of the SAG mill was created using first principle modeling and enhanced with machine learning algorithms – the combination which enables improved monitoring, performance prediction, and optimization to increase profitability.


The circuit comprises a SAG mill, 12 m diameter by 6.1 m length (belly inside liners, the effective grinding volume), two pebble crushers, and two ball mills in parallel closed with cyclones. The SAG mill is fitted with a 20 MW gearless drive motor with bi-directional rotational capacity. (Reversing direction evens out wear on liners with ...


At Eagle, the ball milling circuit starts with a crushing plant and ends with a 12.7-mm screen. "The ball mill is 3.20 m diameter and 4.88 m long," the study said. The discharge typically contains "negligible +12.7-mm material." At the time, "tonnage was 45 metric tons per hour (mt/h), and mill power draw was 709 kW," the study said.


Following implementation of these strategies, SAG mill throughput when treating the harder copper/zinc ores increased from a target of 2,750 mt/h in 2007 to 4,000 mt/h in 2009 and 4,400 mt/h in 2010-11. Optimization of the overall process also resulted in less energy consumption per ton of product. Continuous Improvement Delivers Further Benefits


SAG mill discharge slurry flow rates and densities. The implementation of soft sensors to estimate these variables can provide additional information to aid circuit optimization as well as increasing advanced control system availability. The SAG mill charge estimator combines the SAG mill mass


circuit. The Kinross Paracatu new grinding circ uit consists of one 11.6 x 6.7m (38' x 22') SAG mill with. installed po wer of 20MW, followed by two 7.3 x 12.2m (24' x 40') ball …


Following implementation of these strategies, the SAG mill throughput when treating the harder copper/zinc ores increased from 2,750 tph to an average of 3,600 tph, and the optimization of the overall process improved energy efficiency, resulting in considerably less energy consumption per ton of …


batu hijau sag mill - travelslow.pl. BATU HIJAU MILL THROUGHPUT OPTIMIZATION: MILLING . Figure 1 PT Newmont Nusa Tenggara Batu Hijau Project Comminution Circuit . The SAG Mill was designed with 13.4 MW of installed power for size reduction from a 175mm feed size down to 2 mm -10 mm of product size with given maximum ball charge of 13% by


Also, the mill load varied in the range of 125 to 165 tons. These disturbances propagated throughout the milling circuit and even to the flotation circuit. The Millstar Power Optimiser gave the following benefits: • Mill feed cuts were prevented, resulting in a stable mill loading. • No huge power dips occurred, since any sign of the mill


• Ball Mill Limited: the overall grinding circuit is constrained by the Ball Mill capacity and the SAG mill and Pebble Crusher circuits have spare capacity. This limitation is commonly experienced during the processing of the low grade ores (less than 0.4%Cu). This also confirms theBWi ore hardness – …


AG & SAG Mill Grinding Circuit Automatic Control. It is obviously well understood that autogenous AG and semi-autogenous SAG mills operate quite differently from conventional rod mill or ball mills. Since these mills are of a grate discharge type, they operate with varying loads, with the power drawn by the mill being dependent upon the ...


(pdf) optimization of the sag mill circuit at kinross ... circuit. The Kinross Paracatu new grinding circ uit consists of one 11.6 x 6.7m (38' x 22') SAG mill with. installed po wer of 20MW, followed by two 7.3 x 12.2m (24' x 40') ball mills with ...


An optimization study of the circuit performance was conducted to improve product fineness through circuit surveys, experimental lab work and simulations. ... Furthermore, the SAG mill circuit ...