Energy-Model and Life Cycle-Model for Grinding Processes …
The Bond Work Index (Wi B K) of grinding material was calculated using the Bond formula and Karra algorithm [47,48]. The grindability coefficient of Bond grinding …
Bond Impact Crushing Work Index -Procedure and Table of Crushability
P80 = 25400 x Css x 7Ecc x (0.02Wi + 0.70) / (7Ecc – 2Css) Where Oss = Open-side setting in inches. Css = Closed-side settings in inches. Ecc = Eccentric throw in inches. P80 = Aperture through which 80% of the product will pass. Wi = Work Index. The impact apparatus consists of two pendulum-mounted hammers, mounted on two bicycle …
Energy Use of Fine Grinding in Mineral Processing
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 ...
A New Approach to Bond Grindability and Work Index
The most widely known measure of grindability is Bond Work Index (BWI) which was defined as the resistance of the material to grinding and quantified the specific work input (kWh/t) required to ...
Table of Bond Work Index by Minerals
Limestone: 13.8: 10.3: 12.7: 14.0: 14.0: 14.0: 9.9: 4-36: 177: Limestone burnt: 11.0: 6-18: 5: Magnesite: 12.3: 11.1: 12.2: 12.5: 12.0: 14.6: 5-25: 18: Manganese ore: 13.5: 12.2: 13.4: 14.0: 13.9: 6-23: 19: Magnetite: 11.0: Malartic: 19.1: Marble: 4.1: Marl: …
Energy-Model and Life Cycle-Model for Grinding …
By Bond grinding, the Bond Work Index of the limestone sample was 14.45 kWh/t. During the determination of the Hardgrove Grindability Index (HGI), 50–50 g limestone samples from the …
[PDF] A quick method for Bond work index approximate …
The Bond work index is a measure of ore resistance to crushing and grinding and is determined using the Bond grindability test. Its value constitutes ore characteristic and is used for industrial comminution plants designing. Determining the Bond work index value is quite complicated, timeconsuming and requires trained operating personnel and …
Crushing work index Calculation
The paper by Angove & Dunne (1997) reports a standard deviation in crushing work index tests across laboratories as 4.5. The laboratory CWi value of 27.4 (metric) is almost within 4.5 units of the 22.4 value I calculated, so what you are observing is probably the natural variation in the crushing test.
The Bond work index of limestone and andesite mixtures
Table 1 The Bond work index values obtained by standard the Bond procedure and values calculated according to the mass fraction of the sample components Test sieve, Wi, Wi calcul., Difference, Sample µm kWh/t kWh/t % 74 13.90 / / Limestone : andesite 105 12.77 / / 100 : 0 150 12.63 / / 74 14.51 14.95 3.02 Limestone : andesite 105 13.91 13.81 ...
Limestone grindability in terms of HGI and a new
In terms of grinding energy calculations, Bond Work Index (BWI) was taken into consideration. In addition, proposed method for HGI prediction was employed to understand the possible role of ...
(PDF) Investigate the relationship between of the bond work index …
The Bond work index (BWI) is a well-known method used when selecting comminution equipment, to evaluate the grinding efficiency and to calculate the required grinding power.
The Bond work index of limestone and andesite mixtures
PDF | On Jan 1, 2017, Dejan Todorović and others published The Bond work index of limestone and andesite mixtures | Find, read and cite all the research you need on …
Prediction of Bond's work index from field measurable rock …
For the evaluation of laboratory and industrial experiments, the work index can be determined as follows: BWI = 44.5 P 1 0.23 × G 0.82 10 P − 10 F where BWI = Bond's work index (kWh/sh. Ton), F = 80% passing size of original feed (μm), P = 80% passing size of circuit product (μm), P1 = Test-sieve size (μm) and G = Net grams of …
Tower Mill Operating Work Index
Limestone from minus 4000 microns to 2.4 microns average particle size. Ferrite from minus 1680 microns to 2 microns average particle size. by L D Michaud February 29, 2024 June 3, 2016 Categories Grinding Tags isamill, Tower Mill Work Index, …
A New Approach to the Calculation of Work Index and the …
crystalline materials like limestone and magnesite as well . ... For fine and ultrafine grinding, the Bond work index is an inappropriate measure of grindability, so alternatives are discussed ...
A meaningful expression between bond work index, grindability index …
In this study, limestone samples (a total of 108 sample) were collected from two limestone quarries. The collected samples were initially in the form of palm sized and they were crushed to −2.36 mm. Grinding experiments were conducted in standard HGI (Hardgrove Grindability Index) mill and Ring mill.
Bond Work Index
The ball mill work index laboratory test is conducted by grinding an ore sample prepared to passing 3.36 mm (6 mesh) to product size in the range of 45-150 µm (325-100 …
Prediction of Bond's work index from field measurable rock …
Deniz (2004) [22], presented the relationship between Bond's grindability and breakage parameters of grinding kinetic. He conducted grindability test on 6 limestone samples taken from different regions of Turkey and found the following relation between breakage parameter (S i, a T, β and γ) with correlation coefficients of 0.96, …
(PDF) Variability Study of Bond Work Index and Grindability …
It is a well-known fact that the value of the Bond work index (wi) for a given ore varies along with the grinding size. In this study, a variability bysis is carried out …
Procedure for determination of ball Bond work index in …
Section snippets Grinding kinetics in the Bond ball mill. Tests of grinding kinetics in the Bond ball mill (Fig. 1, Fig. 2) has shown that over a shorter grinding period, the process follows the law of first order kinetics R = R 0 e-kt where R = test-sieve oversize at the time (t); R 0 = test sieve at the beginning of grinding (t = 0); k: grinding rate …
A procedure for rapid determination of the Bond work index
The derived eqs. 9, 15 and 16 make it possible to abbreviate the Bond test to only two grinding tests. The abbreviated procedure for finding the work index is as follows: (1) The work index is determined from feed crushed to minus 3.327 mm (the same as for the standard Bond test). (2) The feed is screened to determine its size distribution ...
Grinding work index according to Bond
Average grinding work index (Wi) by type of mate rial, according to Bond (see table 6.1.): The work index (Wi) expresses the kWh required to reduce a short ton of material from theoretically infinite feed size to 80 % passing a square screen opening of 100 microns. The work index values apply to ball mills grinding wet in closed circuit.
(PDF) Determination of Bond Work Index of Lucky Cement Limestone …
The Bond work index is a research methodology, which is widely used for the estimation of power required to grind the materials. Keeping in view the difficulty in determining this index, many alternatives to the standard method have been explored by
The Bond work index of limestone and andesite mixtures
The Bond work index of limestone and andesite mixtures. This paper investigates grinding of mineral mixtures with different grindabilities in the Bond ball mill. Understanding the ore mixture grinding is of great importance in mineral processing. The energy required for crushing and grinding is presented by the Bond work index and is determined ...
BOND'S WORK INDEX: WHAT IT IS AND WHAT IT ISN'T
by calculating an operating work index where the SEC (E), feed size (F80), and product size (P80) are measured, and the work index (Wi) of the operating industrial circuit is then calculated. The operating work index is useful for performing comparisons of energy efficiency that are corrected for different amounts of size reduction. 2.
The Bond work index of limestone and andesite mixtures
The energy required for crushing and grinding is presented by the Bond work index and is determined by means of Bond grindability test. This paper presents the experimental …
(PDF) Relationship between Bond's work index (Wi) and …
The present work seeks to establish a relationship between Bond's work index (Wi), indexes n (uniformity constant), and K (rate constant) from the theory of grinding kinetics so that by collecting and analyzing only bygone data, a decision could be taken out about the size of the mill. 2. An approach to grinding theory and systems 2.1.
(PDF) Variability Study of Bond Work Index and Grindability Index …
The Bond Work Index (Wi) is a common technique for the estimation of hardness and energy requirement for comminution using ball mills. ... Fine and ultrafine grinding of limestone are frequently ...
The Bond work index of limestone and andesite mixtures
They work index changes of ore mixtures as a found that the energy required for grinding function of the mixture composition, and is most often lower when the components found …
Bond Work Index Formula-Equation
The basic work index equation is: W = 10 Wi/√P – 10 Wi/√F(1) where W is the work input required in kilowatt hours per short ton to grind from 80% passing F microns to 80% passing P microns, and Wi is the work index, or the grinding resistance parameter. It represents the energy input required in kilowatt hours to reduce a s…
(PDF) A Methodology to Estimate Ores Work Index Values …
A Methodolog y to Estimate Ores Work Index Values, Using Miduk Copper. Mine Sample. M. Noaparast1*, S. Rahmati1, G. Jozanikohan1, S. Aslani1and A. Ghorbani1. 1 School of Mining Engineering ...
McLanahan | Hammermill Crushers
The work index is the comminution parameter that expresses the resistance of the material to crushing and grinding. In the case of the HammerMaster and LimeMaster crushers, McLanahan has designed the crusher with rotor dimensions, shaft and bearings to handle a variety of applications at a specific horsepower rating.
A new approach to Bond grindability and work index: dynamic …
Elastic parameters can be determined by using static and dynamic methods. As with the standard Bond method, static methods are difficult and prone to computational mistakes. Dynamic methods are easier to use, with fewer test errors. In this study, the effect of elastic parameters on grinding, and the relationship between them, are investigated.
Determination of Bond Work Index of Limestone | Request …
The Bond work index is a research methodology, which is widely used for the estimation of power required to grind the materials. Keeping in view the difficulty in determining this index, many ...
The Bond work index of limestone and andesite mixtures
The energy required for crushing and grinding is presented by the Bond work index and is determined by means of Bond grindability test. This paper presents the experimental results of the Bond work index values obtained by the standard method on limestone and andesite samples, as well as composite samples…