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sag mill power calculations
2021-01-05T02:01:03+00:00
AG Autogenous SAG SemiAutogenous Mill Design Calculations
Table of ContentsSAG Mill ChargeSAG Mill Horsepower — Drive PowerOre Testing for AG SAG Grinding Mill Design Mill Sizing: After laboratory and pilot plant testing confirm the feasibility of autogenous or semiautogenous grinding, it can be used to establish the exact grinding circuit and mill size In the pilot plant tests, the tare power of the pilot plant mills should be determined The SAG Power Index (SPI) test (Starkey Dobby, 1996) uses a benchscale SAG mill test to determine the specific energy of an industrial SAG mill The test is operated in closed circuit and the time required to grind the material to a P 80 of 17 mm is used to predict AG/SAG Orway Mineral Consultants Canada Ltd Mississauga, ON AG/SAG mills in the data base are up to 40ft in diameter and ball mills are up to 26ft in diameter The measured gross power draws from these mills are plotted against the model predictions in Figure 1 As indicated by this data base the accuracy of the model (1 standard deviation) is 46% GROSS POWER CALCULATOR SMC Testing
Modelling SAG milling power and specific energy
1/1/2015 SAG mill power consumption (Pc) in kW, in 4 grinding circuits (GC1 to GC4) at different % of the fresh feed in the size range −6″ +1″ (−152 +25 mm) It is important to notice that the behaviour shown in Fig 4 is affected by the dependence of the power consumption on the mill sizes This fact will be addressed later on in this paper 3stage ball mills, rod mills or AG/SAG mills when calculating power according to the Bond Third Theory method Rod mill and AG/SAG mill products are similar and tend to be not as steep as a 05 slope when plotted on loglog paper This is because the particle size distribution (PSD), these mills produce have a coarse fraction but also a fi ne fraction which is not credited for in an 80 per A Method of C alculating Autogenous/ SemiAutogenous Existing powerbased calculations for comminution circuits Most modern grinding circuits consist of a primary SAG mill and secondary ball mill Bond’s method is widely used for determining the Powerbased comminution calculations using Ausgrind
TECHNICAL NOTES 8 GRINDING R P King
LG A mill power equation for SAG mills Minerals and Metallurgical Processing Feb 1990 pp5762 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 The basic parameters used in ball mill design (power calculations), rod mill or any tumbling mill sizing are; material to be ground, characteristics, Bond Work Index, bulk density, specific density, desired mill tonnage capacity DTPH, operating % solids or pulp density, feed size as F80 and maximum ‘chunk size’, product size as P80 and maximum and finally the type of circuit open/closed Ball Mill Design/Power Calculation1/1/2016 Methods of estimating SAG mill volumes, mill charges, feed size and power consumptions and optimum speeds of rotation during operation are described The operation and mechanism of grinding and size reduction is explained with the help of solved mathematical examples Computation for determining SAG power index is illustratedAutogenous and SemiAutogenous Mills ScienceDirect
USING THE SMC TEST® TO PREDICT COMMINUTION CIRCUIT
AG/SAG mill and crusher circuit simulations through the use of JKSimMet Independent of this it can be used in powerbased calculations, which in conjunction with the Bond ball work index test, enable the prediction of the specific energy of comminution circuits where such circuits include combinations of any of the following equipment: AG and SAG mills Ball mills Rod mills Crushers High Existing powerbased calculations for comminution circuits Most modern grinding circuits consist of a primary SAG mill and secondary ball mill Bond’s method is widely used for determining the Powerbased comminution calculations using AusgrindSAG mill optimisation using powerbased simulations Author Dr Rajiv Chandramohan, Robert Braun, Greg Lane Paper presented by Dr Rajiv Chandramohan at Comminution '18, Cape Town, South Africa, April 2018 ABSTRACT Ausenco’s Ausgrind comminution program has been the inhouse design tool used on a number of successful projects and technical studies In recent years, Ausgrind has SAG mill optimisation using powerbased simulations Ausenco
Mill power draw models
Mill Power Draw Models The mill power draw models are used to predict how much power will be consumed by a particular type of mill, mill geometry and set of mill operating conditions This power is transferred to the ore and used to predict the throughput when combined with the specific energy consumption models Models of this type do not predict the particle size distribution of a milled 1/1/2016 Methods of estimating SAG mill volumes, mill charges, feed size and power consumptions and optimum speeds of rotation during operation are described The operation and mechanism of grinding and size reduction is explained with the help of solved mathematical examples Computation for determining SAG power index is illustratedAutogenous and SemiAutogenous Mills ScienceDirectMill Volume Filling Calculation This calculation will estimate the volume percentage of charge in a mill based upon the number of lifters exposed above the mill charge Enter total number of lifters: Nt= : toolsmillfilling
: Mill Critical Speed Determination
The "Critical Speed" for a grinding mill is defined as the rotational speed where centrifugal forces equal gravitational forces at the mill shell's inside surface This is the rotational speed where balls will not fall away from the mill's shell Result #1: This mill would need to spin at RPM to be at 100% critical speedSAG mill discharge control is quite involved due to few interactive variables, such as mill discharge sump level, classification hydrocyclone variables (feed density, flow and pressure) and water feed rate to the sump Model predictive control (MPC), which is a multiinput multioutput (MIMO) controller, is very suitable for this purposeThroughput optimisation in milling circuitsthe SAG mill amounting to 512 t/h affecting mill capacity as this took space and limited the capacity for new feed Using ModSim simulator, incorporation of a 100 micron screen on the cyclone underflow stream was simulated The main purpose of the screen is to reduce the re circulating load by removal of fines that are deemed gold liberated enough and directed to the leaching circuit The re FREDA REBECCA SAGMILLING CIRCUIT OPTIMIZATION
THE COMMINUTION CIRCUIT DESIGN FOR THE CONSTANCIA PROJECT
Whilst the 60 x 89 crusher had the volumetric capacity, the SAG mill throughput is sensitive to crusher product size distribution and a target OSS of 150 mm on competent ore would lead to power requirements above 600 kW Hence, the larger 60 x 113 crusher with 1,000 kW motor was selectedoperating at 90% of its maximum power The combined power draw of the SAG mill and ball mill was 8658 kW, which caused partial overgrinding From experience in processing plants outside of China, the power rating of the ball mill should be higher than that of the SAG mill [5] The pebble crusher had an overpowered configuration The Optimizing Performance of SABC Comminution Circuit of the Mill Power Draw Models The mill power draw models are used to predict how much power will be consumed by a particular type of mill, mill geometry and set of mill operating conditions This power is transferred to the ore and used to predict the throughput when combined with the specific energy consumption models Models of this type do not predict the particle size distribution of a milled Mill power draw models
SAG Mill Power Draw YouTube
24/2/2021 Calculation of SAG Mill Power Based Morrell Equations11:0012:30 Mill power draw models for ball mills and SAG mills Alex D 12:3013:30 Lunch 13:3015:00 (tutorial) Example calculation in the software; use a preloaded set of test results to run a mill sizing exercise using the Bond/Barratt method Alex D 15:0015:30 Coffee break PM 15:3017:00 (tutorial) Run the same example calculation in the software using a Powerbased grinding models for design and geometallurgyTo calculate grinding media charge for continuous type ball mill, M = 0 x D2 x L Example how to calculate cement grinding mill balls charge – kefid Mining FLshanghai ball mill for cement grinding cement mill is a corrugated lining designed to obtain maximum power For fine grinding, the charge consists of small calculates the grinding charge of a ball mill Mining
FREDA REBECCA SAGMILLING CIRCUIT OPTIMIZATION
the SAG mill amounting to 512 t/h affecting mill capacity as this took space and limited the capacity for new feed Using ModSim simulator, incorporation of a 100 micron screen on the cyclone underflow stream was simulated The main purpose of the screen is to reduce the re circulating load by removal of fines that are deemed gold liberated enough and directed to the leaching circuit The re operating at 90% of its maximum power The combined power draw of the SAG mill and ball mill was 8658 kW, which caused partial overgrinding From experience in processing plants outside of China, the power rating of the ball mill should be higher than that of the SAG mill [5] The pebble crusher had an overpowered configuration The Optimizing Performance of SABC Comminution Circuit of the Scaleup criterion is the net specific power consumption, ie the power consumed by the mill rotor itself minus all mechanical and electrical losses divided by the feed rate of solids For the full scale mill, specific power is multiplied by the feed rate to get the net mill powerAMIT 135: Lesson 6 Grinding Circuit – Mining Mill Operator
OSTIGOV Technical Report: Improving Energy Efficiency Via
Depending on the mill size the SAG mills draws between 2 MW and 17 MW The product from the SAG mill is further reduced in size using pebble crushers and ball mills Hence, typical gold or copper ore requires between 20 and 75 kWh per ton of energy to reduce the particle size Considering a typical mining operation processes 10,000 to 100,000 tons per day the energy expenditure in grinding SAG Calculator View All Technical Tools Radius of Curvature (mm): Diameter (mm): Sag (mm): $$ \text{SAG} = R \sqrt{R^2 \left( \frac{D}{2} \right)^2} $$ R : Radius of Curvature: D : Diameter: Description Determine the sag of a surface based on radius of curvature and diameter Related Product Category: Optical Lenses View All Now Was this content useful to you? Thank you for rating SAG Calculator Edmund OpticsWhen future tonnage is to be increased, the SAG Mill can feed downstream ball milling to boost capacity FullerTraylor SAG/AG Mills range in size from 43m through 122m in diameter with powers as high as 28,000 kW Our team of product engineers continually improves SAG/AG Mill designs in order to provide the most robust, safe, and efficient grinding mills available Key design features Autogenous and SemiAutogenous Mills