Design engineers generally use Bond Work Index and Bond energy equation to estimate specific energy requirements for ball milling operations. Morrell has proposed different equations for the Work Index and specific energy, which are claimed to have a wider range of application. In this paper an attempt has been made to provide a comparison of these two approaches and bring out their ...
The ball mill is designed to accept a ball charge in accordance with F. C Bond's standard. This ball charge consists of 286 balls as follows: 44 x 35mm balls; 67 x 30mm balls; 10 x balls, 71 x balls and; 94 x balls; Fully automated version of the Bond Index Ball Mill is also available on request.
In the standard AC closed circuit ball mill grindability test the work index is found from. where Pi is the opening in microns of the sieve mesh tested, and Gbp is the net grams of mesh undersize produced per revolution of the 12″ x 12″ test ball mill. The closed circuit 80% passing size P averages P1/log 20 for all sizes larger than 150 mesh.
A Bond Ball Mill Work Index test is a standard test for determining the ball mill work index of a sample of ore. It was developed by Fred Bond in 1952 and modified in 1961 (JKMRC CO., 2006). This index is widely used in the mineral industry for comparing the resistance of different materials to ball milling, for estimating the energy required ...
An alternative mill ball charge is proposed that closely approximates Bond's original total ball mass, number of balls and ball surface area. Results of 30 Bond Work index tests of six pure materials (calcite, magnesite, labradorite (feldspar), quartz, andalusite and glass) using closing screen apertures (P 1 ) values of 500, 250, 125, 90 and ...
b) Bond Work Index Both Rod Mill (Wr) and Ball Mill (Wb) The Bond test is used to predict the energy required for coarse material grinding between the 80% passing feed size and the split size ...
in a Bond ball mill for, 1, 2, 4, and 8 min. After each grinding cycle, the grinding product PSD is determined and returned to the mill for the subsequent grinding cycle.
The Bond work index, W i, is defined in a Bond ball mill on the samples of standard size − + 0 mm. In practice, it is possible to find materials of nonstandard size that are finer than mm.. In this work, a procedure for the calculation of the Bond work index is suggested for cases when the Bond grindability test is conducted on samples of nonstandard size.
This Table of Ball Mill Bond Work Index of Minerals is a summary as tested on 'around the world sample'. You can find the SG of each mineral samples on the other table. Source 1. Source 2. Source 3. Source 3. Source 4.
Key words: Comminution, Bond work index, Grinding, Crushing, Ball mills, Rod Mills. Theoretical efficiency In their book Process Engineering of Size Reduction Ball Milling, Austin, Klimpel and Luckie (1984) stated that, "We have tried throughout this book to avoid the use of the term grinding efficiency because the degree of conversion of
The Work Index (BWi) is calculated according to Fred Bond's Equation. Bond Work Index for Testing Procedure. Cleaning and Storing of Ball Mill Charge after the Bond Work Index Procedure is done: Add about 500 g of silica sand into the mill containing the ball charge. Seal the mill. Rotate for 20 revolutions to clean.
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 ...
and the Bond Ball Mill Work Index Test (GMG, 2021). The sampling and surveying guideline (GMG, 2016) pro vides addi tional detail on how to collect the required data and is critical to this analysis.
The FC Bond Work Index Test Ball Mill was designed by F. C. Bond for use in determining the Bond Index, a measure of grindability and power required for grinding applications. The FC Bond Mills are used in laboratories throughout the world. A copy of Fred C. Bond's Method of Crushing and Grinding for determination of the Bond Index is included with each mill. This mill can be used to calculate ...
The Bond Ball Mill is a small universal laboratory mill used in calculating the grindability of ... (Gbp) is the ball mill grindability. The ball mill work index, Wi (kWh/short ton) is calculated from the following equation (Bond 1961):1 The mill should be cleaned by either blowing air into it or wiping the interior with a cloth and or
Bond ball mill w ork index test is used to ca lculate the work index rel ated to fine grinding (Mib). Mia and Mib are used to cal culate Ecs for the coarse (Wa) and fine (Wb) components acc ording .
Reference mineral (Granite) of known weight and work index ( Kwh /tone) was ground for 30 minutes at a particular speed and power consumed was determined from the power rating of the ball mill. An identical weight of Wasagu Manganese ore whose work index was to be determined was ground in the same ball mill under same condition as
Conclusions. The power model and linear model both will give reasonable P80 estimates given the P100 of a Bond ball mill work index test product. The power model might be marginally more robust ...
Bond Ball Mill (BBM) Standard Test The procedures to carry out the Bond grindability tests in ball mills and rod mills are outlined in Sections and They are usually referred to as the standard tests, but it
A Bond Work index mill ball charge and closing screen product size distributions for grinding crystalline grains. Int. J. Miner. Process., 165 (2017), pp. 814, / View PDF View article View in Scopus Google Scholar. Menéndez et al., 2018.
A standard Bond mill (Fig. 1) was designed to perform the work index tests and determine the energy consumption of various s mill has a round internal housing at the corners, has no lifters, and is for dry grinding. The inner diameter and the length are m, and the ball load is % of mill volume (equaling a total weight of kg).
The Bond's standard ball mill is used to determine the work index value of differ ent samples. The Bond work index is defined as the kilowatthours per short ton required to break from infinite size to a product size of 80% passing 100 µm. If the breakage characteristics of a material remain constant over all size ranges, the calcul ated work ...
It is a wellknown 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 with the Bond standard grindability tests on different critical metal ores (W, Ta), ranging from coarse grinding (rod mills) to fine grinding (ball mills). The relationship between wi and grinding size did not show a clear ...
The Bond Work Index (Wi) is a common technique for the estimation of hardness and energy requirement for comminution using ball mills. However, this technique is timeconsuming (close to 5 hours ...
µm. Note that—in order for no correction factor for ball mill product fineness to apply—the ball mill circuit P80 should be no less than approximately 70 µm (Bond, 1962). This Bond Efficiency determination should not be applied to circuits with a P80 finer than approximately 70 µm without making qualifications. 3.
Bond Work Index (BWI) Hardgrove Grindability Index (HGI) tests for biomass coal. • BWI can predict the potential for mill choking of biomass in a tube and ball mill. • HGI is a poor method of predicting grindability of biomass in vertical spindle mills. • Pellets should be composed of predensified particles close to the target size. •
Bond Ball mill work index determination (1 reply) s. srinu1234. 5 years ago. srinu1234 5 years ago. Dear all, Have a good day! I am trying to determine ball mill work index for a very soft . If I follow bonds procedure to do experiment, not able to determine. The following is the data of ore sample. F80% = 2300mic.
Fred Bond published an article in 1961, which, described the procedure for testing ores for a Bond Ball Index. This parameter is still one of the most demanded tools in the design, evaluation and optimization of ball grinding plants around the world. However, the testing methodology for the Bond Dall Index requires about 10 kg of
The Bond work index, Wi, is defined in a Bond ball mill on the samples of standard size − + 0 mm. In practice, it is possible to find materials of nonstandard size that are finer than 3. ...
The Ball mill work index is the final Bond work index, applicable to the size range of ball milling (very roughly: from mm to about 75 µm; yes, it overlaps the Rod Mill Wi range). More on ...
For the ball mill grindability test, the work index is calculated from the following revised equation (in short tons): where: Pi = sieve size tested (microns) Gpb = ball mill grind ability Wi, P F have the same meanings as in the top equation. Equipment required: Laboratory ball mill, cm x cm with following ball charge: Agitator ...
The work index equation for a ball mill test was generated by Fred Bond to empirically predict the operating work index of an industrial ball mill (8 ft dia by 8 ft effective grinding length ...
world. It shows that the ball mill work index is normally distributed with an average of and a median of kWh/t. bOnd rOd mill GrindAbility The Bond Rod Mill Grindability Test is performed similarly to the ball mill test. The feed sample is stagecrushed to ½" and the test is run under a 100% circulating load. As in the ball mill ...
You need a twostage solution, first stage opencircuit mill and then second stage closedcircuit mill. First stage, will be broken into two parts as well, you use a Bond rod mill work index for the coarse component of the ore (+ mm) and the Bond ball mill work index for the fine component ( mm).
© DZCrusher - كل الحقوق محفوظة
