sag mill and closed circuit ball mill

2019-09-16T11:09:35+00:00

SAG Mill Grinding Circuit Design 911metallurgist

By combining with SAG discharge and screening on the SAG discharge screens, top size control to the ballmill circuit feed is maintained while still unloading the SAG circuit (Mosher et al, 2006) A variant of this method is to direct pebblecrushing circuit product to the ballmill proposed flowsheet consists of existing SAG mill circuit followed by a new proposed ball mill in closed circuit with the existing hydrocyclone package In all simulations, SAGT, CYCL and MILL models were selected to simulate SAG mill, Hydrocyclone packages and ball mill units SAGT and MILL models both are based on the population balance model Chapter M MODELLING, SIMULATION, OPTIMIZATIONThe circuit comprises a SAG mill, 12 m diameter by 61 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 bidirectional rotational capacity (Reversing direction evens out wear on liners with Grinding Circuit an overview ScienceDirect Topics

AMIT 135: Lesson 6 Grinding Circuit – Mining Mill

AG/SAG mills 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 of a ball mill Because of the range of mill sizes available, AG/SAG milling can often be accomplished with fewer lines than in a conventional rod mill/ball mill circuitCFnet is an empirical adjustment to a ball mill circuit [CFnet = 235 029 × ln(P80)] Morrell Mi model: Morrell (2008) published a twoparameter model based on two equations (3 4) to describe a variety of comminution devices, including singlestage SAG and AG millsPowerbased modelling of singlestage AG and SAG mill Your problem can occur in a SAG Mill or Ball Mill Other point to consider is the particle size distribution, it is possible to receive a finer ore from the mine and the particle size distribution of the product from the crushing circuit is different, In this case, the residence time in the tumbling mill Grinding Circuit Overload Grinding Classification

USING THE SMC TEST® TO PREDICT COMMINUTION

ball mill cyclone overflow The closed circuit crusher distribution can be seen to be relatively steep compared with the open circuit crusher distribution and ball mill cyclone overflow Also the open circuit distribution more closely follows the gradient of the cyclone overflow If a ball mill circuit were to be fed 2 distributions, each with A ball mill operates more with the grinding surface action of the balls than the impact form of grinding that the rod mill uses Taking this into account you can see that if the rod mill doesn’t reduce the ore to a size that the ball mill can reduce quickly, the circuit Operating and Troubleshooting a Grinding Circuit The ball mill has higher circulation load, it generates only 30 35% of actual fines you require to be called as product If your product size needed is 100% passing 45 micron, then the ball mill total discharge material will contain normally 30% of 45 micron High recirculating loads in Ball Mill Circuits Grinding

Method of assessing ball mill health

method to assess the health of a closedcircuit ball mill circuit by separating the overall circuit efficiency into separate efficiency measurements for the classification and grinding components of the circuit This permits plant metallurgists to determine which unit operations (hydrocyclone or grinding mill) require optimization 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 yearsFREDA REBECCA SAGMILLING CIRCUIT OPTIMIZATION circuit is shown in Figure1 It is commonly referred to as a SABC circuit, for SemiAutogenous Ball mill Crusher (SABC) This circuit shows a semiautogenous grinding (SAG)/ball mill circuit where both grinding mills are in closed circuit, with the SAG mill closed with a crusher to control the amount of ‘critical size’ material in the circuitOptimizing Performance of SABC Comminution Circuit of

Page 1 Page 2 INTRODUCTION SAG Orway

ScrubBall Scrubber, open circuit classification, followed by a closed circuit Ball Mill SS SAG Primary crushing followed by a single stage SAG Mill SAB Primary crushing followed by a SAG Ball circuit SABC Primary crushing followed by a SAG Ball circuit with recycle crusher ABC Primary crushing followed by a AG Ball circuit with recycle crusher focused on the energy and cost comparisons of the existing AG/SAG ball mill circuits with two proposed comminution circuits, including an HPGR ball mill circuit and a novel HPGR stirred mill circuit The main objective of this research was to advance the understanding of the potentialCOMPARISON OF HPGR BALL MILL AND HPGR The circuit comprises a SAG mill, 12 m diameter by 61 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 bidirectional rotational capacity (Reversing direction evens out wear on liners with Grinding Mills an overview ScienceDirect Topics

Autogenous mill and semiautogenous mill

While AG mills operate without a ball charge, SAG mills use a grinding media charge of normally 3 % 12 % for comminuting the feed material The maximum feed size is between 200 mm and 500 mm The AG/SAG mill is normally installed upstream of a tube mill operating in closed circuit 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 The importance of cyclone performance should Expert mill control at AngloGold Ashanti 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 speedAN OVERVIEW OF SINGLE STAGE AUTOGENOUS AND

USING THE SMC TEST® TO PREDICT COMMINUTION

ball mill cyclone overflow The closed circuit crusher distribution can be seen to be relatively steep compared with the open circuit crusher distribution and ball mill cyclone overflow Also the open circuit distribution more closely follows the gradient of the cyclone overflow If a ball mill circuit were to be fed 2 distributions, each with proposed flowsheet consists of existing SAG mill circuit followed by a new proposed ball mill in closed circuit with the existing hydrocyclone package In all simulations, SAGT, CYCL and MILL models were selected to simulate SAG mill, Hydrocyclone packages and ball mill units SAGT and MILL models both are based on the population balance model Chapter M MODELLING, SIMULATION, OPTIMIZATION circuit is shown in Figure1 It is commonly referred to as a SABC circuit, for SemiAutogenous Ball mill Crusher (SABC) This circuit shows a semiautogenous grinding (SAG)/ball mill circuit where both grinding mills are in closed circuit, with the SAG mill closed with a crusher to control the amount of ‘critical size’ material in the circuitOptimizing Performance of SABC Comminution Circuit of

Adriatic Metals plc PreFeasibility Study Metallurgy

The grinding circuit consists of a SAG mill, ball mill and cyclones The grinding circuit will be designed to reduce ore from an 80% passing size of 76mm to 40µm The SAG mill will be a single pinion low aspect mill, operating in a closed circuit The mill has an inside diameter of 38m and an effective grinding length (EGL) of 50m The mill Table 2 and 3 include the process and operating data for the Copper Mountain SAG mill Table 2 general SAG mill circuit and ore data Specification Data Operating circuit Closedcircuit Operating mill ball charge 15 percent by volume Operating mill total charge 32 percent by volume Mill speed 1008 RPM (76 percent of critical speed average)Paper # 25 Copper Mountain Overview on the 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 onlyAutogenous and SemiAutogenous Mills

Expert mill control at AngloGold Ashanti

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 The importance of cyclone performance should Ball Mill Grinding Circuit The ball mill is in closed circuit with a sump and three cyclone classifiers The ore and trim water are added to the ball mill and the outflow from the ball mill goes to a sump where additional water is added The slurry from the ball mill is pumped out of a sump into two cyclone separators The underflow from the Advanced Controller for Grinding Mills: Results from a conventional SAG mill based circuits, a pilot scale study was conducted to compare the energy requirements of the existing SABC circuit at the Huckl eberry Mine to two alternative circuits: an HPGR ball mill circuit and a novel HPGR stirred mill circuit The study was conducted in *C Wang , S Nadolski , O Mejia , J Drozdiak , B Klein

Grinding control strategy on the conventional milling

The only manipulated variable available in the closed milling circuit (ball mill 2) is the cyclone dilution water flow rate Attempts to use this for density control were not successful Because of the high magnetite concentration of the ore it was found that the actual density exceeded the required density, ball mill cyclone overflow The closed circuit crusher distribution can be seen to be relatively steep compared with the open circuit crusher distribution and ball mill cyclone overflow Also the open circuit distribution more closely follows the gradient of the cyclone overflow If a ball mill circuit were to be fed 2 distributions, each with USING THE SMC TEST® TO PREDICT COMMINUTION