Semi autogenous grinding (SAG) mills, because of their advantages in terms of capital and operating costs, were the natural choice for mines as their primary grinding mill option. Then, in the late 1980s when the price of copper rose quickly from a low of /lb to a high of /lb, this substantial increase in price further fuelled the
Choosing a SAG Mill To Achieve Design Performance John Starkey1, Principal Consulting Engineer Sami Hindstrom2, Manager, Grinding Travis Orser2, Project Manager, Grinding 1 Starkey Associates Grinding Design and Process Engineering 336 – 268 Lakeshore Rd. E. Oakville, Ontario L6J 7S4
Grinding mill machine is an essential part of many industrial processes, there are mainly five types of mills to cover more than 90% materials sizereduction applications. Do you the difference between the ball mill, rod mills, SAG mill, tube mill, pebble mill? In the previous article, I made a comparison of ball mill and rod mill. Today, we
SAG milling extends itself to many applications due to the range of mill sizes available. They can accomplish the same size reduction work as two or three stages of crushing and screening, a rod mill and some or all of the work done by a ball mill. SAG mills are also an optimum solution for wet grinding since crushing and screening in these
The Grinding Circuit optimization Application is the first technology to accurately predict critical SAG Mill performance variables. It then correlates this data to give an accurate picture of conditions inside the mill. This allows mines to reduce downtime in operations by reducing scheduled liner wear inspections and unnecessary changes.
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,, van der Westhuizen,, Mainza, 2009).
Rely on our proven track record of SAG and AG Mill superiority. Since the early 1980s, we have been designing and manufacturing SemiAutogenous (SAG) and Autogenous (AG) Grinding Mills under the FullerTraylor brand. Semiautogenous grinding uses a minimal ball charge in the range of 615% while autogenous grinding uses ore only.
Starting as small as 13 feet (4 m) in diameter on 330 HP and as large as 24'' ( m) in diameter on 3,300 HP, the 911MPE Semi Fully Autogenous Mills tumble crushed ore without iron or steel grinding media. They are used when the crushed ore pieces are hard enough to perform all the grinding. SAG mills tumble mainly ore but they use up to 15% volume of steel balls to assist grinding. Semi
The power draw of the SAG mill has room for significant improvement. As ball filling in the SAG mill is quite low, additional grinding media would likely increase the processing capacity of the SAG mill; however, the capacity of the ball mill, with installed power
A robust, accurate laboratory SAG test has been needed for years. The SAGDesign Consulting Group has developed such a test. This paper also presents case studies in how it is used. Feed is prepared from ~10 kg of half core samples by crushing to 80% passing 19mm. Grinding is then done in a m diameter SAG mill to 80% passing 12 mesh US
Sep 07, 2008· During assembly of the SAG mill, a 10,000tonne goldrich bulk sample is being run through a Knelson concentrator circuit as 40 individual 250tonne blocks. In order to calculate gold content of each block, full gold cleanup is done at the end of each block run.
Topics covered by this course include Grinding Circuit Basics, AG and SAG Mill Circuits, and Ball and Rod Mill Circuits. In recent years the mineral processing industry has downsized its labor force, installed new technology with larger equipment and incorporated plant wide automation, all in an effort to improve productivity and performance
Oct 12, 2017· SAG mill make use of steel balls included with some large and hard rocks for grinding. These mills utilize the balls in making the large fragments of materials broken into pieces. The ball charge of a SAG mill is about 9% to 20%.This process takes place inside the large rotating drum of SAG mill which is filled with balls partially.
Jan 08, 2016· In this training module, we''ll cover the workings of a semiautogenous grinding mill, or SAG mill, that''s designed to be the first stage of a grinding circuit. Ore that''s crushed in a primary
In SAG mill operation, the grinding rate passes through a minimum at a "critical size" (Chapter 5), which represents material too large to be broken by the steel grinding media, but has a low selfbreakage rate. If the critical size material, typically 25–50 mm, is accumulated the mill energy efficiency will deteriorate, and the mill feed
ball mill and sag mill SAG mills use a ball charge of 8 to 21%. The largest SAG mill is 42'' () in diameter, powered by a 28 MW (38,000 HP) motor. A SAG mill with a 44'' () diameter and a power of 35 MW (47,000 HP) has been designed. Attrition between grinding balls and ore particles causes grinding of finer particles.
The CSE Uniserve Modern SER Drive is a compact, powerful, multifunctional and reliable addition to other SAG mill control technologies on the market today. Electrical features The CSE Uniserve Modern SER is designed, manufactured and tested to the ISO 61800 family of standards, meaning you can be sure it will operate in almost any site or
The mill produces copper and gold concentrate from mined ore through a process to separate valuable minerals from the impurities covering them. The main steps in the process are crushing, grinding, flotation, and dewatering. Crushing and grinding transform ore size into fine sand in order to release particles containing copper and gold.
The grinding circuit for the Copper Mountain project consists of one FL SAG mill and two FL ball mills. Figure 1 Overview grinding circuit The Copper Mountain SAG mill is 10363 mm [34 feet] in diameter and 6096 mm [20 feet] long. It is a grate discharge mill with an inside diameter of 10363 mm [34 feet] and a grinding length of 5334
a mill grindout (no ore feed) of 10 to 20 minutes is also performed before mill inspection or relining. The complete grindout is required to obtain the accurate ball load measurement or the percentage by volume of balls in the mill. This is usually performed soon after a crash stop.
stabilizes the operation of the SAG mill, resulting in improved operation and increased production. BrainWave SAG mill is a unique control package using patented modelbased predictive adaptive control technology. It is well known within the mining industry that effective grinding in a SAG mill depends largely on the loading of the mill. A mill
distribution affects the SAG mill load and the load affects directly the mill power and the efficiency of the mill operation (Van Nierop and Moys, 2001). If a SAG mill has been designed with a conventional power or specific energy model which do not consider the projected feed size distribution it is likely that this mill
bling mills (AG/SAG, rod, and ball mills) involved in reducing the size of the primary crusher product to that of the final product (usually the cyclone overflow of the last stage of grinding prior to flotation/leaching). 2. Feed rate to the circuit (dry tonnes/h) 3. Power draw of the comminution equipment (kW)
Sep 24, 2012· FINLAND – At metres diameter and metres long, the new semiautogenous mill that Outotec is building may well be the largest SAG mill in the huge mill will offer increased efficiency, effective grinding conditions, 15% greater mill capacity, and reduced energy consumption.