Crushing & Grinding Machines

INFERENTIAL MEASUREMENT OF SAG MILL PARAMETERS

semiautogenous grinding SAG mills and is the last in a five-part series on Inferential Measurement of SAG Mill Parameters Inferential measurements of SAG mill discharge and feed streams and mill rock and ball charge levels detailed earlier in the series are utilised in a simulation environment...

Model Morrell SS SAG

Ball mill Wi test closing screen size umclosing 181 m Ball mill Wi test product size P 80 181 m Ball mill Wi test feed size F 80 181 m Ball mill Wi grams per revolution at test conclusion gpr Required parameters F 80 181 m is the 80 passing size of the fresh feed to the circuit expected to be a Bond-compatible size distribution P 80...

20150806 Survey Sample Grinding Circuits

F80 80 passing size of the circuit feed μm HPGR High Pressure Grinding Roll P80 80 passing size of the circuit product μm PSD Particle Size Distribution ROM Run-of-Mine SAG Semi-Autogenous Grinding SMC Test® SAG Mill Comminution Test 3 KEYWORDS Autogenous Grinding AG mill Ball mill Comminution...

Modelling SAG milling power and specific energy

Jan 01 2015 0183 32 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...

A General Model for Semi

an 8 m diameter SAG mill with LID = 05 grinding a copper ore and predicted maximum capacity and minimum kWh/ton at about 6070 ball load at 25070 complex function of the feed size distribution and specific rates of breakage However it is still convenient to define a mean residence time by solid hold-up W divided by solid feed rate...

Model Bond/Barratt SABC Models

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 E peb...

Understanding Size Effects of Semi

Oct 10 2016 0183 32 Although it is well known and easily experienced that the feed size distribution influences the throughput and stability of operation of a semi-autogenous grinding SAG mill the details are poorly understood since it is often only the input and output measurements that are used to identify unfavourable in-mill conditions...

GEOMETALLURGY APPLIED IN COMMINUTION TO

specific energy requirements of SAB SAG and ball mill and SABC SAG and ball mill with-pebble crushing circuits for mill design purpos Ultimately an example is presented to demonstrate the application of this method can be used to evaluate and minimize design risks...

Evaluating the effect of feed particles size and their

Nov 16 2016 0183 32 Nowadays experimental semi-autogenous SAG mill and drop-weight test are used for evaluation of grinding circuit regarding changes in feed particle size distribution size of the ball speed of mill prediction of energy required and product size distribution for complete grinding in AG and SAG mills...

Optimization and Performance of Grinding Circuits The

fluctuating feed size of between x F 80 =102 to 185 mm A need for control of the feed size as well as blending ratios was recommended for an efficient operation in terms of throughput and final product size This could be achieved through closer monitoring of the primary crusher performance and proper control of the ratios for the SAG mill...

What s the Difference Between SAG Mill and Ball Mill

Nov 26 2019 0183 32 The feed size is usually between 20-30mm and the product size is 0-3mm Feed Both the autogenous grinding mill and the ball mill feed parts are welded with groove and embedded inner wear-resistant lining plate As the sag mill does not contain grinding medium the abrasion and impact on the equipment are relatively small...

performance curves of sag mill

2016-6-15 respect with SAG mills being increasingly less sensitive as the ball charge is increased Morrel S and Valery W 2001 22 EFFECT OF FEED SIZE DISTRIBUTION ON SAG MILLING The qualitative effect of changes in particle size distributions PSD on the SAG mill performance can be addressed by using the grind curv Get Price...

FREDA REBECCA SAGMILLING CIRCUIT OPTIMIZATION

respect with SAG mills being increasingly less sensitive as the ball charge is increased Morrel S and Valery W 2001 22 EFFECT OF FEED SIZE DISTRIBUTION ON SAG MILLING The qualitative effect of changes in particle size distributions PSD on the SAG mill performance can be addressed by using the grind curv...

t10 63 x 53 The SCSE Parameter the JK Drop Weight A

AG/SAG mills for a given feed size distribution and feed rate Morrell and Morrison 1996 Hence when using JKSimMet in a design situation the dimensions of the AG/SAG mill are adjusted until the load in the mill reaches 25 by volume when fed at the required feed rate The model predicts the...

factors that affect sag mill performance

factors affecting the performance of the sag mill factors affecting the performance of the sag mill Modelling S milling power and specific energy alterations etc are the most important factors affecting the S mills performance Some operations have recognised an opportunity in the relationship between feed size and mill performance and manipulate feed size to and...

Unlock SAG mill capacity with process control optimization

Alternatively if high energy impacts are detected the SAG mill speed is reduced to protect the liners Although this works well in most scenarios changes to the feed conditions ie competency size distribution can shift the base layer reading for high energy impacts and create false positives or...

Taking Control of the Mill Feed R2

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...

Optimizing Performance of SABC Comminution Circuit of

Minerals 2016 6 127 3 of 9 back to the SAG mill This causes a higher variation in the feed rate and particle size distribution in the feed to the SAG mill which results in a greater variation in the SAG mill power draw in the transition...

20150821 Morrell Method

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/leach-ing 2 Feed rate to the circuit dry tonnes/h 3 Power draw of the comminution equipment kW...

PDF Optimisation of the Sossego SAG mill Mauricio

A implemented at the Sossego SAG mill briefly described as follows SPLIT on-line size distribution analyzer was later installed at the SAG mill feed conveyor All these actions resulted in a much more controlled First Generation size distribution of primary crusher discharge Table 3 shows the results obtained during May 2006...

Modelling SAG milling power and specific energy

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 con-sider the projected feed size distribution it is likely that this mill...

TECHNICAL NOTES 8 GRINDING R P King

LG A mill power equation for SAG mills Minerals and Metallurgical Processing Feb 1990 pp57-62 Gross power No load power Net power drawn by the charge 813 The net power is calculated from Net power KD25L e c/ Watts 814 In equation 814 D is the diameter inside the mill liners and Le is the effective length of the mill including the...

5 Use the JKSimMet SAG default breakage rates for design

Set A b and ta appearance function parameters in SAG model = to the actual ore type values for the ore that has been drop tested and is currently being simulated 12 If SAG feed size distribution has no plus 200 mm material add a 200 mm screen to feed size screen set and set retained to 001 will not change size distribution...

INFERENTIAL MEASUREMENT OF SAG MILL PARAMETERS IV

The oversize crusher feed size distribution oscf and the primary cyclone feed size distribution pcfd are estimated utilising the SAG mill grate size and discharge screen aperture sizes and the Rosin-Rammler size distribution function which has been selected for its convenience and since it has been found to fit many...

The SAG grindability index test

Jan 01 2014 0183 32 The mill reportedly rotates at 70 of critical velocity Verret et al 2011 or 54 rpm Gonzalez 2000 There is controversy surrounding the mill rotational speed The calculation of mill critical velocity V c is derived from the balance of gravitational force and the centrifugal force acting on a ball and is given by Eq after Austin and Concha 1994 1 V c = 422 D-d where D is the...

Blasting design for increased SAG mill productivity

SAG mill throughput is often a bottleneck to increasing plant productivity Improved size distribution control in the mill feed can be used to increase mill production This can be accomplished by controlling blast fragmentation as a function of energy input and rock characteristics Such an approach requires the integration of rock fragmentation and comminution modeling...

PDF Influence of feed size on AG / SAG mill performance

The feed size distribution together with the ore characteristics hardness lithology alterations etc are the most important factors affecting the SAG mills performance...

Characterization and Modeling of Semi

The qualitative e ect of changes in ore size distribution OSD on the performance of the mill can be addressed using the grindcurves Powell and Mainza 2006 of the SAG mill under analysis The operation of SAG mills is extremely sensitive to mill lling from a qualitative point of view for a given ll level and constant feed rate and...

Control of Size Distribution of the Ore Feeding a Semi

A control strategy for the ore feed size distribution is assessed using a simulator of the ore stockpile operationINTRODUCTIONThe popularity of autogeneous FAG and semi autogeneous SAG grinding mills has been increasing over the last 20 years Napier Munn et al 1996...

OUTOTEC GRINDING TECHNOLOGIES

used where a narrow product size distribution is required for example for subsequent gravity separation MH Series Grinding Mills A standard range of SAG ball and rod mills with spherical roller bearing technology enabling faster delivery and start-up lead time OUR MILL RANGE Pebble mills Outotec has a long history of successfully...