Specific energy of mill compared to new created surface energy → not meaningful, efficiency much smaller that 1% ... energy/specific work of comminution Particle strength by compression Specific work of comminution ... Tumbling mill Vibrating mill Planetary ball mill Stirred ball mill Mills …
BM = Ball mill specific energy from T 80 1.7 mm to final product P 80, using Bond's Law, (kWh/t) W T = Total grinding mill circuit specific energy (kWh/t) Note that K BM is the composite of EF3, EF4 and EF5 factors for ball milling (Rowland, 1982). Morrell and SMCC Morrell (2004) developed a methodology for predicting specific energy with
Apr 10, 2021· specific power consumption of ball mills for line. specific power consumption of ball mills for line. Our company is committed to building crushing, industrial grinding, ore processing and green building materials, and provides intelligent solutions and mature supporting products.The products includes five series: crusher, sand making machine, powder grinding mill, mineral processing …
Specific comminution energy of ball mills 2012 pdf milling analysis of particles autumn 2010 7 3 mills figure 4 specific comminution energy according to rittinger bond and kick 3 mills 31 mills with loose milling tools ball mills are the most important group of such machines .
12.00 Influence of the mineralogical structure in grinding specific energy consumption of itabirite iron ores D.B. Mazzinghy, H.D.G. Turrer, J.F.C. Russo (Iron Ore Brazil–Anglo American, Brazil) and L.M. Tavares (Universidade Federal do Rio de Janeiro, Brazil) 12.20 Finding the mill setting sweet spot – a DEM assisted case study
The model predicts the total comminution energy of most types of plant that contain conventional crushers, High Pressure Grinding Rolls (HPGR) and wet tumbling mills such as Autogenous (AG) Semi-autogenous (SAG), rod and ball mills. As well as the total specific energy it will also predict
The specific energies of the SAG and ball mills were determined using AusGrind (Ausenco's in-house software) (Lane, Foggiatto, Bueno and McLean, 2013 and Morrell's ) method. SAG mill specific energy was a function of the inverse of the Axb value, the mill geometry and the mill operating conditions.
4, 2012. The paper presents the analysis of efficiency of the work of ball and rod mills ... evaluated by the factor describing increase of certain chosen particle size ... determining fine particle fractions before operations of comminution is crucial ... Keywords: comminution, ball mills, rod mills, fine particles, energy consumption. Read more
Specific Energy Requirement and Design. These equations form the Basis of DJB's "Millpower2000" Simulation Program for estimating power requirements and mill sizes vs mill throughput objectives. It is an iterative process, but the software can accommodate a large number of geo-comminution samples in a time-efficient manner.
Comminution '08 Falmouth, UK, June 17-20, 2008 ... replacing ball mills • Media wear ... Weber showed that there is a minimum in the correlation between specific grinding energy and stress intensity. The stress intensity is given by, where v T is the peripheral (or maximum) particle velocity. This can be …
Dec 18, 2013· where W is the specific grinding energy (kWh/t), W i is the Bond ball mill work index (kWh/t), F80 is the feed 80 pct passing size (μm), and P80 is the product 80 pct passing size (μm). It can be seen that in the regime in which the Bond equation is valid, energy use increases exponentially as product size decreases with constant feed size ...
Feb 01, 2016· 1. Introduction. A specific energy-based size reduction model for batch grinding ball mills has been developed (Shi and Xie, 2015).The objective of this work was to overcome the limitations in the existing JKMRC (Julius Kruttschnitt Mineral Research Centre) perfect mixing ball mill model, including the use of a set of default breakage appearance functions for all ores, and the lumped model ...
THE EFFECT OF BALL MILL PARAMETERS ON MINERAL LIBERATION Hector E. Rojas Committee Chairman: Dr. G.T. Adel ... the breakage rates and energy specific breakage rates indicate that a change in breakage kinetics may be ... United States power consumption is related to comminution (Comminution and Energy Consumption, 1981). With this in
working. He says traditional ball mills' large grinding media consume huge amounts of energy for fine grinding and the slow rotation mill speed results in low power intensity. "Low power intensity in a ball mill cannot deliver the high mill throughput required. And the impact and abrasive stresses used in ball mills do not work well for
Oct 01, 2018· SLW: Another example of improving wear life for increased mill performance, including reduced specific energy consumption, is given in a paper by Sever Ciutina ( MLS) and R.J.Soriano (Senior ...
the literature, two more-established circuits, a cone crusher / ball mill and an .... stirred mill circuit in a study examining the need for a reduction in the energy ..... provides a best-case scenario for the crushing circuit. ... results indicated that a pressing force of 4 N/mm2 provided a fine balance between energy …
A particle size reduction model has been developed as the first component of an upgraded ball mill model. The model is based on a specific energy-size reduction function, which calculates the particle breakage index, t 10, according to the size-specific energy, and then calculates the full product size distribution using the t 10-t n relationships and the mass-size balance approach.
particle breakage versus energy data was converted into breakage rates with the impact energy spectra of the grinding mill. The proof of the modeling concepts is shown for a 90 cm laboratory scale ball mill. The material used in the study was limestone. In the batch mill, approximately a …
C.2.4 Fine Particle Tumbling Mill Specific Energy 11 C.2.5 Total Net Comminution Specific Energy 12 C.3 Conventional Crushing/Ball Mill Circuit 12
total specific energy consumption of the comminution system is 20 to 50 % less compared to conventional ball mills. The double rolls used for the process are on the first glance similar in design to conventional crushing, compacting or briquetting rolls but differ considerably in details, particularly in view of the very high separating force.
specific comminution energy of ball mills 01 pdf ME. For tumbling mills the specific comminution energy (Wi) relates to the power at the pinion or for gearless drives the motor output. the purposes of this approach it has been assumed that the additional specific energy for ball milling is the same as the difference in specific energy between ...
SHAPES ON BALL MILL PERFORMANCE ... Comminution is an important process in mineral processing, power plants, cement ... terms of energy requirements and steel consumption related to grinding media and liners. Spherical grinding media are predominantly used in final stages of ore grinding. The spherical balls change shape through breakage and ...
The Features of Energy-saving Ball Mill . Compared with traditional ball mill, the energy saving ball mill fan save power 18-25%, lubricant 70% and cooling water 90%, and comprehensively save energy above 20%. Regularly, it doesn't need change the main shaft in 10 years, which will save much maintenance fee and labour hours
08.30 The influence of the water balance and classifier choice on the energy efficiency of milling circuits A. Hinde (Independent Consultant, South Africa), E. Ford (Mintek, South Africa) and J. Makola ( Solutions International, South Africa) 08.50 An analysis of classification innovations in closed circuit ball mills
The Journal of The Southern African Institute of Mining and Metallurgy VOLUME 110 NON-REFEREED PAPER MARCH 2010 141 Relationships between comminution energy and product size for a magnetite ore specific comminution energy at pinion (kWh/t), x2 is the 80% [4] passing size for the product ( m) and x1 is the 80% passing size for the feed ( m).
specific net mill power, the following Eqns. (4)–(8) can be used to determine the specific rate of breakage S i (1/min), for each size class i obtained after grinding, as a function of J. Bond F.C. (1960) proposed the following relationship for wet grinding in overflow ball mills to scale-up results from laboratory tests to larger mills
In the past 20 years, the energy-efficient comminution technologies, including high pressure grinding rolls (HPGR) and high speed stirred mill, have been developed and adopted in the ... Table 5.5 Calculation of ball mill circuit specific energy for AG/SAG mill circuits .....76 Table 5.6 Calculation of ball mill circuit specific energy for HPGR ...
The Karara iron ore project is a magnetite operation consist of open pit mining and concentrator to produce high-grade magnetite concentrate. The concentrator has adopted three stages of comminution, ie fine crushing in the high pressure grinding rolls (HPGR), primary ball milling and fine grinding in the TowerMill plus magnetic separation in between these comminution devices.
the ball mill is less energy efficient than a crusher and has to input more energy to do the same amount of size reduction). Hence from equation 7, to crush to the ball mill circuit feed size (x. 2) in open circuit requires specific energy equivalent to: f x f x 2. 1 W c ic. 1.19* 4 2 M x x. 1 (10) For closed circuit crushing the specific ...
Comminution is a process that results in particle breakage caused by the impact of the mill structural elements and/or contacts between moving (often very fast) particles [].As was studied so far, comminution could be an effect of crushing, attrition, cutting, splitting, bending, breaking and hitting [].The choice of the best grinding method depends primarily on the properties of the material ...
tional ball mills (fine particles) it is labelled Mib, W is the specific comminution energy at pinion (kWh/t), x 2 is the 80% passing size for the product ( m) and x 1 is the 80% passing size for the feed ( m). [9] The work index related to the breakage property of an …
Nov 08, 2016· Table 1 shows a comparison of the specific energy values calculated from Eqs. () and for the 100 mesh test sieve (S = 150 µm) and seven values of G in the range of 0.33–3 g/rev.It can be seen that at a G value of 1.5 both the equations give the same estimate of the specific energy. For G values greater than 1.5 the Bond equation gives relatively higher values, and for G values smaller than ...
For tumbling mills the specific comminution energy (Wi) relates to the power at the pinion or for gearless drives - the motor output. For HPGRs it is the energy inputted ... ball mill is less energy efficient than a crusher and has to input more energy to do the same amount of size reduction). Hence from equation 7, to crush to the ball mill
conventional comminution devices like tumbling ball mills. 2.1 Roller ... total specific energy consumption of the comminution system is 20 to 50 % less ... roller press and the effect of roller press grinding on the energy consumption of the ..... In Equation (3), the number of contacts, BZ, increases quadratically with ratio of the.
given mill on comminution efficiency. Specifically, using, mill and comminution circuit temperature data ... - specific heats of the ore and water [kJ/kg-K], T 2, T 1 ... the average portion of energy input into ball mill grinding lost to the environment which in this case is 30% or 681 kW. Using mill make-up water (16C) as the cold source and ...
feed for the rod mill, i.e. 10000 μm in accordance with Table. The value of P 80 is accepted based on the required grain-size characteristics of the ball mill discharge. Considering the Bond energy law and the correction factors by Rolland, the total specific energy E req required for comminution of mineral from the initial size F 80 (coarse
A more in-depth look at ball mill operation clearly sug - gests the richness of the information hidden behind the value of specific energy in an operation, which should be regarded as merely an average number. The emphasis on this number suggests, in principle, that it would not mat-ter how the material receives energy, just the amount.