### (PDF) Influence of feed size on AG / SAG mill performance

Jan 01, 2001 When the feed size of a SAG mill becomes coarser, i.e. α r increases, the energy required to break the ore increases, i.e. φ r and φ f increases (Morrell et al., 1996; Morrell and Valery, 2001 ...

Get PriceEmail contact### IMPROVEMENTS IN SAG MILL THROUGHPUT FROM FINER

identify where the opportunities were greatest and what effect the combined changes would have on mill performance. Initially, the focus was to reduce the SAG mill feed size while processing the lower tonnage Subika ore and improve the grinding circuit product size while processing the

Get PriceEmail contact### Modelling SAG milling power and specific energy ...

The feed size distribution is also the implicit result of the ore competence (affecting blasting and crushing performance). This 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

Get PriceEmail contact### Modelling SAG milling power and specific energy ...

Jan 01, 2015 The feed size distribution is also the implicit result of the ore competence (affecting blasting and crushing performance). This 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

Get PriceEmail contact### Application of Operating Work Indices in Autogenous ...

terms such as “SAG mill inefficiency factor.” As ore breakage characteristics can be a major factor in AG/SAG mill product size distribution, Figure 2 compares only data for porphyry ores. Before the true power efficiency of an AG/SAG grinding mill can be properly assessed by using the Wio concept, the T 80 used for calculations must be

Get PriceEmail contact### Multi-component AG/SAG mill model - ScienceDirect

Apr 01, 2013 The grinding media of autogenous mills derive from the feed ore size and composition (Delboni and Morrell, 1996) and the varying ratio of different components in the mill feed affects the mill charge and consequently the whole breakage process. after developing a new AG/SAG mill model that describes the influence of mill charge composition on breakage performance, Delboni (1999) recommended investigating multi-component ore

Get PriceEmail contact### Taking Control of the Mill Feed R2 - Metallurgy

The effect of feed size in AG/SAG milling has been studied extensively with an early review presented by Abel (1997), whilst the relationship between changes in feed size and comminution has been covered by a number of authors under the banner of “Mine to Mill” (Morrell and Kojovic, 1999).

Get PriceEmail contact### Feed Size VS Ball Size - Grinding Classification ...

Feed Size VS Ball Size - Grinding Classification Circuits - Metallurgist Mineral Processing Engineer. Does anyone have a chart to know if there is any relation between the feed size and the size of the ball needed to grind the ore in SAG and Ball mills?

Get PriceEmail contact### (PDF) CURRENT TRENDS IN SAG AND AG MILL OPERABILITY AND ...

Figure 4 shows the effect on the feed rate system on one of the SAG mills at Telfer, prior to the Manta Cube feed control being implemented. A drop in feed is noticeable when one of the feeder ...

Get PriceEmail contact### INFERENTIAL MEASUREMENT OF SAG MILL PARAMETERS IV ...

rate [t/hr], smdc is the SAG mill discharge size distribution [%retained w/w], MV DC_H2O is the SAG mill discharge water addition rate measured variable 3[m3/hr] and SG l is the process water specific gravity [t/m ]. Step 2: SAG Mill Rock Charge The SAG mill rock charge properties (SMRC) and size distribution (smrc) are estimated by the reverse-

Get PriceEmail contact### (PDF) CURRENT TRENDS IN SAG AND AG MILL OPERABILITY

The Effect Of Variable Ore Type ... The SAG mill power distribution shows a shift to the right, indicating that ... and decoupling control technology to overcome the variations of feed ore ...

Get PriceEmail contact### Improved Relationships for Discharge in SAG/AG Mills

of grate/pulp lifter design in AG/SAG mill discharge. The current understanding from literature lacks knowledge of mill content size distribution and its effect on discharge through the grate at various aperture sizes and radial positions. It also indicates that in ... on the grate is driven by the factors of ore filling, radial position and ...

Get PriceEmail contact### A Neural Network Model for SAG Mill Control

SAG specific power range of about 3 to 9 kWh/t for this site. The design of the ore stockpiling and conveying system contributes to fluctuating size distribution with significant short-term segregation occurring under certain operating situations. Depending on ore type and feed size distribution, each SAG mill will process between 700 and 3000 tph.

Get PriceEmail contact### (PDF) Design of the biggest mill in the world

Surveys of the SAG mill during the first four weeks of operation showed the feed size distribution, transfer size and pebble rate to be lower or less than those catered for in the design.

Get PriceEmail contact### SAG mill Archives - International Mining

The maximum feed size, f 100, at the gold mine trials was limited to 50 mm to ensure free flow through the feed spout. RD culminated in pilot-scale operational trials at the Akbakai gold mine (Kazakhstan), owned by JSC AK Altynalmas, in 2020, where SAG mill rejects of hard underground quartz/gold ore

Get PriceEmail contact### Application of response surface methodology for modeling ...

Sep 01, 2013 The size distribution of ore prepared for ball mill feed was shown in Fig. 1. As shown in Fig. 1, the d80 of sample (as ball mill feed) was 480 μm. The measured Bond work index of ore was 16 that obtained from Bond grindability test. Download : Download full-size image; Fig. 1. Size distribution of the laboratory ball mill feed.

Get PriceEmail contact### GEOMETALLURGY APPLIED IN COMMINUTION TO

independently of ore domains. Freeport-McMoRan’s project Amelunxen et al. (2011) The trade-off economics of SAG mill and HPGR-based circuits were primarily determined for the average ore hardness, and then the performance of the two circuits were modelled over the LOM hardness and head grade plans, resulting in estimated throughputs,

Get PriceEmail contact### SAG Mill Optimization using Model Predictive Control

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, M.S., van der Westhuizen, A.P., Mainza, A.N. 2009).

Get PriceEmail contact### Mine to Mill 2020 - Advanced Mine to Mill Optimisation ...

The Advanced Mine to Mill concept recognised these limitations and developed practical strategies to address them. A brief list of some of these strategies is given below: Produce optimum size distribution (not just finer) and balancing the transfer size between the SAG and ball mill to improve the overall circuit throughput (Powell et.al 2018).

Get PriceEmail contact### A specific energy-based ball mill model: From batch ...

Feb 01, 2016 Since this size (DWT testing 13.2–63 mm particles in narrow size fractions) is too coarse for a ball mill feed and the A × b value at this size is irrelevant to ball milling, a nominal size of 2 mm is used to compare ore competence for ball mill feed.

Get PriceEmail contact### Lime use and functionality in sulphide mineral flotation ...

Nov 01, 2019 Primary grinding – Lime is often added into the semi-autogenous (SAG) mill together with the ore feed and process water. Sulfide minerals are, by nature, acid to varying degrees causing the milled pulp to have a pH ranging from 4 to 8 depending on the sulphide and gangue mineral composition of the ore.

Get PriceEmail contact### Effect of ball and feed particle size distribution on the ...

N2 - In this article, alternative forms of optimizing the milling efficiency of a laboratory scale ball mill by varying the grinding media size distribution and the feed material particle size distribution were investigated. Silica ore was used as the test material.

Get PriceEmail contact### Model:Bond/Barratt SABC Models - SAGMILLING.COM

The ball mill oversize feed factor (EF 4 BM) is always calculated with the rod mill work index for the optimum feed size and the ball mill work index for EF 4 BM. The model assumes that the calculated value of E ssbm + the specified contingency is greater than the sum of E sag

Get PriceEmail contact### Advanced Simulation for Semi-Autogenous Mill Systems: A ...

and size distribution, water discharge rate, ball throughput, bearing pressure, pebble throughput, and toe and shoulder angles of the internal load. 2.1 SAG mill model The particles fed to the mill are ground in the milling chamber and subsequently downloaded into the discharge zone, where, according to a classification probability, they

Get PriceEmail contact### (PDF) CURRENT TRENDS IN SAG AND AG MILL OPERABILITY

The Effect Of Variable Ore Type ... The SAG mill power distribution shows a shift to the right, indicating that ... and decoupling control technology to overcome the variations of feed ore ...

Get PriceEmail contact### Improved Relationships for Discharge in SAG/AG Mills

of grate/pulp lifter design in AG/SAG mill discharge. The current understanding from literature lacks knowledge of mill content size distribution and its effect on discharge through the grate at various aperture sizes and radial positions. It also indicates that in ... on the grate is driven by the factors of ore filling, radial position and ...

Get PriceEmail contact### A Neural Network Model for SAG Mill Control

SAG specific power range of about 3 to 9 kWh/t for this site. The design of the ore stockpiling and conveying system contributes to fluctuating size distribution with significant short-term segregation occurring under certain operating situations. Depending on ore type and feed size distribution, each SAG mill will process between 700 and 3000 tph.

Get PriceEmail contact### Advanced Simulation for Semi-Autogenous Mill Systems: A ...

and size distribution, water discharge rate, ball throughput, bearing pressure, pebble throughput, and toe and shoulder angles of the internal load. 2.1 SAG mill model The particles fed to the mill are ground in the milling chamber and subsequently downloaded into the discharge zone, where, according to a classification probability, they

Get PriceEmail contact### SAG mill Archives - International Mining

The maximum feed size, f 100, at the gold mine trials was limited to 50 mm to ensure free flow through the feed spout. RD culminated in pilot-scale operational trials at the Akbakai gold mine (Kazakhstan), owned by JSC AK Altynalmas, in 2020, where SAG mill rejects of hard underground quartz/gold ore

Get PriceEmail contact### Application of CEET and FLEET in the Base Metals Industry

• SAG Mill Size - 30.5 cm (1 ft) diameter by 10.2 mm (4 inches) long • Steel Charge - 2.5 cm (1 inch) diameter balls • Test Feed - 2 kg of dry ore crushed to 80% passing 12.7 mm • Test Product Required - 80% passing 10 mesh (1.7 mm) The test procedure involves the dry grinding of the 2 kg of crushed ore (SAG . feed or core sample) in a ...

Get PriceEmail contact### Mine to Mill 2020 - Advanced Mine to Mill Optimisation ...

The Advanced Mine to Mill concept recognised these limitations and developed practical strategies to address them. A brief list of some of these strategies is given below: Produce optimum size distribution (not just finer) and balancing the transfer size between the SAG and ball mill to improve the overall circuit throughput (Powell et.al 2018).

Get PriceEmail contact### SAG Mill Optimization using Model Predictive Control

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, M.S., van der Westhuizen, A.P., Mainza, A.N. 2009).

Get PriceEmail contact### Throughput optimisation in milling circuits

If the mill feed setpoint is changed, then the actual feed rate needs to stabilise at the new target in a short period of time. The feed rate setpoint can then be tied into a SAG mill power optimisation strategy. SAG Mill Discharge. Controlling the feed and discharge of a mill is mostly a stabilisation exercise – you need to be able to ...

Get PriceEmail contact### Comminution - Wikipedia

Comminution is the reduction of solid materials from one average particle size to a smaller average particle size, by crushing, grinding, cutting, vibrating, or other processes. In geology, it occurs naturally during faulting in the upper part of the Earth's crust. In industry, it is an important unit operation in mineral processing, ceramics, electronics, and other fields, accomplished with ...

Get PriceEmail contact### SAG Mill Testing - Test Procedures to Characterize Ore ...

build up over time. For AG/SAG mills, this may result in a critical size build-up and associated throughput losses. The importance of steady-state testing increases with the ore heterogeneity. On the other hand, the batch tests (e.g. Mod Bond, SPI®, SMC Test®) generally require less sample, which make them more suitable candidates for variability

Get PriceEmail contact### Telfer Project Process Plant Design

1. SAG milling and/or fine crushing to –2mm and gravity concentration to 15% of feed mass followed by ball milling and differential flotation of copper and pyrite concentrates. 2. SAG/ball milling and generation of a bulk flotation concentrate for hydrometallurgical plant treatment on site. 3.

Get PriceEmail contact### Influence of blasting on the size distribution and ...

2.2 Blasting effects on energy consumption in crushing and grinding 8 2.3 Mine to mill and optimisation 12 2.4 General summary of blasting influence on downstream conditions 15 3. Description of blasting results 17 3.1 Fragment size distribution 17 3.2 Other fragment properties 18 3.3 Damage aspects 19 4.

Get PriceEmail contact### Effect of Particle Size and Grinding Time on Gold ...

Effect of Particle Size and Grinding Time on Gold ... A 100 kg ore sample was collected from the rod mill feed conveyor of the concentrator, crushed ... the ore size distribution. The plant uses a ...

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