PDF | On Jan 1, 2011, A. P .P van der Westhuizen and others published Milling curves as a tool for characterising SAG mill performance | Find, read and cite all the research you need on ResearchGate
A mill is a grinder used to grind and blend solid or hard materials into smaller pieces by means of shear, impact and compression methods. Grinding mill machine is an essential part of many industrial …
Process variables like bearing pressures or load cell measurement can be applied for better correlation. 3. Actual application and resultsThe outlined method was applied in a 36 × 17 ft −15 000 HP (11.2 MW) variable-speed semiautogenous (SAG) mill for copper ore concentration with nominal throughput of 24 000 tons per day. The mill is …
Although this was a low aspect SAG mill operated with a very high ball load in closed circuit, the power response is generic. ... This indicates that for a mill on load cells two points can ...
AG/SAG mill: One of the few remaining Hardinge 6' x 2' high aspect pilot 18 kW SAG mills in the world is fully operational at the ALS Metallurgy, Balcatta campus in Western Australia. Installed with a shell hatch to facilitate easy charge removal, the mill is installed on load cells connected to a SCADA system to collect mill weight, mill ...
A high aspect SAG mill had an ID of 6.0 m and the length measured 4.0 m along the central line. The mill was charged with ore having a S.G. of 2.65 and the load was 40% of the mill volume. The grinding media steel balls occupied 12.2 % of the mill volume. The mill was rotated at 75% of its critical speed, which was 12.9 rpm. Estimate:1.
Mill filling is an important operational parameter in a SAG mill circuit and by its control and optimisation it can produce significant improvements in production capacity and energy efficiency. However, it is industry practice to report mill load as the total output given by load cells, or kPa for systems based on lubrication bearing back ...
Where they are installed, load cells measure the mill and charge total mass. Where load cells are not installed, the total mass can be inferred from bearing pressure. The charge mass is then ... shows the throughput versus SAG mill load for two different liner designs and operating loads, and the power draw versus SAG mill load for the Cadia ...
Where they are installed, load cells measure the mill and charge total mass. Where load cells are not installed, the total mass can be inferred from bearing pressure. …
designing the new SAG mill chamber for optimum conditions at the design point is clearly established. For the operating load range just beyond the optimum performance conditions, a linear model was developed to assess the lost production that would result from running the mill at too high a load level.
Mill filling is an important operational parameter in a SAG mill circuit and by its control and optimisation it can produce significant improvements in production capacity and energy efficiency. However, it is industry practice to report mill load as the total output given by load cells, or kPa for systems based on lubrication bearing back pressure, rather than …
Sag mills in the gold and copper operations would vary from 6%- 15% and are normally grate discharge types in most cases the densities of the slurry in the mill is over 65% and that goes for ball mills also. ... Modern mills operate with load cells and mill optimizer's which synchronize the mill weight, power draw, ore feed and weight with ...
The article discusses the topic of the specific power consumption of a drum mill type SAG 8.5x5.3. The purpose of the study is to<br> determine the influence of some basic parameters like angular velocity of the mill drum, the wear on the drum's lining, mass of the mill filling, loading rate of the mill with ore and flow rate of incoming water of the …
Although this was a low aspect SAG mill operated with a very high ball load in closed circuit, the power response is generic. Download : Download full-size image; ... This indicates that for a mill on load cells two points can reliably be used to calibrate the fill–load correlation. Thus one stop when the mill is in normal operating condition ...
The cornerstone of effective SAG mill control lies in accurately measuring the mill load. There are two primary methods: Direct measurement: This method utilises …
The SAG mill has four load cells installed at . 13TH AUSIMM MILL OPERATORS' CONFERENCE / PERTH, WA, 10–12 OCTOBER 2016 understAnding siZe effects Of semi-AutOgenOus grinding mill OPer AtiOn As A PAthWAy tO sOlVing feed disturbAnces 323 the discharge end of the mill, two at ±16.5° (F1 and F3), and
Calculating a grinding circuit's circulating loads based on Screen Analysis of its slurries.. Compared to %Solids or Density based Circulating load equations, a more precise method of determining grinding circuit tonnages uses the screen size distributions of the pulps instead of the dilution ratios.Pulp samples collected around the ball mill or rod …
The Impactmeter is an advanced SAG mill performance monitoring instrument developed to measure load generated impacts and provide mill liner protection through the use of …
The sensitivity analysis of the GANN model shows that the work index, inlet water to the SAG mill, mill load cell weight, SAG mill solid percentage, mass flowrate and feed moisture have a direct relationship with mill power, while outlet water to the SAG mill has an inverse relationship with mill power. Expand
Because SAG mills rely both on the ore itself as grinding media (to varying degrees) and on ore-dependent unit power requirements for milling to the transfer size, …
Thereafter, this idea was investigated by Toor, Franke, Powell, , and Waters (2013) on the 32 ft semi-autogenous grinding (SAG) mill at concentrator Two at Newcrest's Cadia Valley Operation (CVO).
A SAG mill consists of a rotating drum filled with steel balls or rods, and the rock that needs to be ground. The drum is mounted on a stationary structure, which houses the motor, gear, reducer, and bearings. ... The mill weight is measured by load cells or a strain gauge, and the controller adjusts the feed rate accordingly. SAG mills can be ...
A linkedin group was recently discussing this by asking: I've tried to estimate AG/SAG Mill power requirements using several different methods: (1) Using the results of SMC data (2) Using SAG Power Index (SPI) data (3) Using the 1989 Barratt method updated on Alex Doll's Web site (February 16, 2015) (3) Using Don Burgess' …
If the SAG mill is not intended to be the rate-limiting step in a process plant, then it is best to adjust the SAG load (and power) to hold a constant tonnage to satisfy another constraint elsewhere. Underground mines are an example: the hoisting capacity of the mine shaft is the rate-limiting step in the process, and the SAG mill must adapt to ...
SAG MILL TESTING - AN OVERVIEW OF THE TEST PROCEDURES AVAILABLE TO CHARACTERIZE ORE GRINDABILITY AUTHOR: F.O. VERRET, G. CHIASSON AND A. MCKEN - SGS KEYWORDS Comminution, grindability, grinding, SAG mill, AG mill, milling, HPGR, work index, pilot plant INTRODUCTION The resistance of ore samples to …
(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]).
1. Introduction. Mill filling has a dominant effect on grinding mill performance (Apelt, Asprey and Thornhill, 2001), and therefore, its accurate measurement is vital for modelling grinding mill performance.Measuring filling is also necessary to estimate the composition of the load for mill modelling: rock and slurry for AG mills; rock, balls and …
SAG mill powerdraw [kW] SAG mill load cell [t] Cyclone feed water addition [m 3/hr] Cyclone feedrate [m /hr] Cyclone feed density [% solids w/w] Oversize c rusher feedrate [t/hr] Ore is fed to the SAG mill for primary grinding. The mill discharge is screened with the oversized material
Provide a motor with the capability to deliver design power on a continuous basis by including a suitable service factor, usually 15% to cover any drive losses and …
Conditions inside your mill are automatically adjusted to minimise liner damage, stabilise and then optimise the operation of a SAG Mill. With the combination of ECS/ProcessExpert and LoadIQ, your mill will grind more efficiently, helping to reduce energy consumption while lifting throughput and extending the life of your mill liners and ...
of the SAG model, i.e. the throughput, the power draw, the load cell value and the P80. Additionally, considering that there is a desired transfer size from the SAG circuit to downstream processes ...
Yes, you add load cells to existing SAG Mills; it depends on the type of mill bearing support system. They are normally button type compressive cells. With Polysius mills they are integral in the Feed end bearing pedestals and provide a load signal out via an amplifier …
Load cells and power monitoring are sometimes used but are generally poor indicators of the mechanisms that lead to such unwanted conditions. At the MMG Century operation …
This paper discusses inferential measurement models for semiautogenous grinding (SAG) mills. Inferential measurements of SAG mill discharge and feed …
There are few methods of semi-autogenous (SAG) mill power prediction in the full-scale without using long experiments. In this work, the effects of different operating parameters such as feed moisture, mass flowrate, mill load cell mass, SAG mill solid percentage, inlet and outlet water to the SAG mill and work index are studied. A total …
Westwood grinding circuit. 2.1 Semi-autogenous mill model The grinding process in a SAG mill as described by Sbárbaro (2010) is st ti li ti f si l t s i- t s ll- ill i i i it . . érez- arcÃa ∗ J. ouchard ∗,∗∗ . oulin ∗,∗∗∗ ∗ niversité Laval, L, entre 4, avillon drien- ouliot ...
SAG Mill process control classically maintains the SAG mill volumetric filling within a set operating range. Typically a SAG mill weight measurement, by either bearing pressure transducers or load cells, is used as an inferred measurement of volumetric filling. To maintain volumetric filling within a set operating range the SAG …
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). Power draw ranged between 18.0MW and 19.0MW. In order to draw more power the options immediately …