ball mill work index

A Bond Work index mill ball charge and closing screen product size distributions for grinding crystalline grains Int. J. Miner. Process., 165 ( 2017 ), pp. 8 - 14, 10.1016/j.minpro.2017.05.011

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 kilowatt-hours 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

work index values tend to remain the same for different product sizes. As a supplement to this study, rod and ball mill grindability tests were run on the porphyry copper ore at sizes of 4 through 65 mesh for the rod mill tests and 14 through 325 mesh for the ball mill tests. These tests were run to determine the changes in work index values,

The Bond Ball Mill Work Index remains today as the only tool used for ball mill scale-up design. For an (only nominally, not at all materially modified) update on its use for industrial mill sizing, see " Selection of Rod Mills, Ball Mills, Pebble Mills, and Regrind Mills," Rowland, C. A., Jr., 1982, Chapter 23, Design and Installation of ...

2. Calculate the Standard Circuit Bond Work Index (WiSTD) for the material being processed (equation 3). Wtotal WiSTD= –––––––––––– (3) 10 10 (––––－––––) √￣P80 √￣F80 The Bond Standard Circuit is the "conventional" crush-ing-rod-ball …

Abstract The Bond work index, Wi, is defined in a Bond ball mill on the samples of standard size − 3.327 + 0 mm. In practice, it is possible to find materials of non-standard size that are finer than …

After which, the ore was grinded in a ball mill until a 250% circulating load was achieved. The Bond work index was then calculated to be equal to 41.38 kWh/tone. I. Introduction Comminution is the process of reducing particle size by breaking, crushing and grinding until the valuable minerals are minute enough and can be isolated by such ...

of the cyclone underflow back to SAG mill, introduction of a second classification stage as well as introduction of a second ball mill. The evaluation of breakage tests and survey data revealed the following; the Bond work index obtained for the current ore ranges between 17.20 - …

A Bond Ball Mill Work Index may also be used in the simulation and optimisation of existing mill(s) and the associated grinding circuit(s). Sample requirements: A minimum of 8 kg of material crushed to nominally minus 10 mm is preferred. JKTech would stage crush the sample to minus 3.35 mm, as required for the Bond Ball Mill Work Index test feed.

Bond ball mill work index. The method requires all the elements of the ball mill work index test to be filled in: Ball mill Wi test closing screen size, umclosing, µm; Ball mill Wi test product size, P 80, µm; Ball mill Wi test feed size, F 80, µm; Ball mill Wi grams per revolution at test conclusion, gpr; Required parameters

Catalog excerpts. BALL MILLS, ROD MILLS & BOND INDEX MILLS Labtech Essa manufacture a range of metallurgical laboratory sized ball and rod mills to suit most applications. Included in the range is a Bond index mill which has specific application in establishing the grindability of ores (see sheet 2 of this data sheet) The ball and the rod mill ...

This video was put together by Joshua Wright and Aldo Vasquerizo as a supplemental lecture for University of Nevada Reno.If you have any questions, need advi...

This process includes a bond ball mill work index of 20.4-kilowatt-hours per tonne, a leach feed grind size distribution of 150 microns, and cyanide consumptions of 0.5 grams per tonne. Tesoro said the results from its testwork …

The Bond Ball Mill Work Index (BBWi) test is carried out in a standardised ball mill with a pre-defined media and ore charge. The Work Index calculated from the testing can be used in the design and analysis of ball mill circuits The test requires a minimum of 10kg of sample that has been stage-crushed to passing size of <3.35 mm.

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.

Work index can change as a function of the product size of a Bond ball mill grindability test, which is controlled by the closing mesh size …

4.4.2 Bond Ball Mill Work index Results: Wi=25.23 kwh/t Reduction ratio is 2.98 Analysis: The sub-samples were compared to determine BWi (Bond Work Index) for unknown sample. With formation of trendline with respect to the size distribution for known and unknown samples, F80 and P80 for respective sub-samples was obtained from the interpolation ...

The work index of a particular material is determined in the laboratory by conducting the standard Bond grindability test. Bond developed separate tests for the rod mill and the ball mill. The simplified test method described in this paper is an alternative procedure to the ball mill grindability test.

The aim of this study was to develop a new method for assessing the Bond work index in a ball mill (BBWI), which is based on a first order kinetics present in the Bond ball mill for grinding mineral raw materials (Austin et al., 1981; Ahmadi and Shahsavari, 2009). Theoretical basis of quick procedure

C) for coarse rocks (75-50 mm), a rod mill work index (Wi RM) for intermediate sized particles (25-3 mm), and a ball mill work index (Wi BM) for small particles (<3 mm) (Ammtec, 2000). Laboratory testwork is required to determine these Work Indices, and each test requires carefully collected samples of rock that is representative of future mill ...

The Bond grindability testing procedure has been standardized to obtain the same grindability values, i.e., Bond work index (BWi), on the same ore when tests are performed in different laboratories or by different operators. This is accomplished by the standardization of mill dimensions, tumbling speed, grinding-ball charge weight and distribution, sample charge …

The Bond ball mill grindability test is run in a laboratory until a circulating load of 250% is developed. It provides the Bond Ball Mill Work Index which expresses the …

The Work Index (BWi) is calculated according to Fred Bond's Equation. Bond Work Index for Testing Procedure Cleaning and Storing of Ball …

Work Index Ball Mill, alluding to the grind ability list of Metals, is utilized to demonstrate the granulating trouble of the material. It is measured by a rule that to compute the work file ball plant in light of yield of every unrest of the factory after the material is ground to an adjusted state by the predetermined plan.

published his method of energy calculation with an index called Bond work index (Bond 1961). In the 1970s, the population balance or selection and breakage function model was at the forefront of research (Fuerstenau et al. 1973). A number of advancements were made in the application of this model to ball mill grinding.

SAGDesign testing provides SAG pinion energy grindability in kWh/t to within +/- 5% from 152 to 1.7 mm, and Bond Ball Mill Work Index on SAG ground ore, from the SAG test on the same sample. Starkey & Associates uses the patented SAGDesign technology to calculate accurate mill sizes from measurements on a client's own ore samples.

Determination Of The Bond Work Index Using An Ordinary . Numerically the work index is the energy required in kwh/t to reduce a given material from theoretically infinite feed size to 80 passing 100 microns The work index of a particular material is determined in the laboratory by conducting the standard Bond grindability test Bond developed separate tests for the rod mill …

XMGQΦ305 Grinding Bond Ball (Rod) Mill is mainly applied for testing the grinding work index of the material of every kinds of ores, slag, etc. Under the specific rotation speed for dry grinding, then screening the products, weighing, repeat operation several times, getting the grinding work index kWh/t. Technical Parameters:

Ball Mill Wio, BWio 86 Circuit Wio, OWio 146 Bond Ball Mill Work Index, BWi, kWh/t 134 Bond Rod Mill Work Index, RWi, kWh/t 181 Table 1 Example of AG/SAG Ball Mill Circuit Wio Calculations [1] [2] ABstrAct Optimum use of power in grinding, both in terms of grinding efficiency and use of installed capital, can have a large effect on .

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 mesh), thus determining the ball mill work index ( WiB or BWi ).