3- STANDARD BOND TESTS 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
This ball mill, also called mill for measuring bond work index, is a key device for measuring grinding work index. It is widely used by teaching and researching departments for grindability test of ores raw materials for cement and its mixtures.
Bond ball mill and grind for an arbitrary number of mill revolutions (N 1 = 50, 100 or 150 revolutions). After grinding, screen the sample on the comparative sieve and determine
WiBM Bond Ball Mill Test Work Index (kWh/t) Wic Bond Impact Crushing Test Work Index (kWh/t) WioACT Actual Operating Bond Work Index determined from measurements on the circuit (kWh/t) WiRM Bond Rod Mill Test Work Index (kWh/t) WiSTD Standard Circuit Bond Work Index (expected or designed) used for circuit design. Specific energy requirement at ...
The Bond Ball Mill Grindability Test is a locked-cycle laboratory grinding test. It provides the Bond Ball Mill Work Index which expresses the resistance of a material to ball milling. This Index is widely used in the mineral industry for comparing the resistance of different materials to ball milling, for estimating the energy
Bond Work Index (BWI) Test. Celtest have the capability to carry out the Bond Work Index (BWI) Test in accordance with EPRI Report CS3612 : FGD Chemistry and Analytical Method Handbook, Volume 2 . The BWI is used to estimate the required mill power per ton of product (Specific Energy). The specific energy requirements and the desired production ...
rod mill Work Index test for these purposes. Chose a o closing screen for the ball mill test one (standard square root of 2 series) mesh size coarser than the plant ball mill circuit P80. If between standard mesh sizes, the finer of the chose two. Results of Bond ball mill tests conducted with closing
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 ...
ball mill work index was averaging only 11.6 kWh/t, which is not hard. A rod mill work index fi gure was not found but was thought to be in the 16 kWh/t to 18 kWh/t range. The Xstrata Zinc 22 ft ID × 40 ft EGL over ow ball mill fl was installed at Mt Isa in 2009. This mill was put into single
We have bond ball mill work hardness jktech,a modified Bond ball mill procedure Mod Bond was developed by MinnovEX Technologies now SGS which requires 12kg of sample crushed at minus 335mm The 12kg charge is milled with the standard Bond ball mill for a set time A particle size analysis is performed on the feed and ground product and a modified work index is calculated using a proprietary …
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.
submitted to the Bond ball mill work index test. The number of SAG mill revolutions required to grind the material to a P 80 of 1.7 mm is used to predict AG/SAG specific energy using quation 4. Correction E factors for feed size and pebble ing are applied to …
micrometers in size. According to the Bond standard procedure, the work index is determined by simulating a dry grinding in a closed circuit in the Bond ball mill to achieve 250% circulating load (Bond, 1949, 1952, 1961). The test is performed on a raw material approximately weighing 10 kg, which coarseness is -3.327 mm.
The Bond Index conforming rod charge consists of: 6 rods of 1.25" diameter and 21" length. 2 rods of 1.75" diameter and 21" length. The grinding jar for the Bond Index Rod Mill is 12″ x 24″ in size and has a wave-shaped design. At least 15 to 20 kg sample material is required to simulate a closed grinding circuit in a ball or rod mill.
In this regard calculation of work index of limestone made by standard Bond grindability test. Ball mill was employed to conduct the grinding test of seven different samples. Among all seven samples collected from the different faces of quarry, Bond work index of limestone Face4A results less than 20kwh/t, remaining 6 samples are marked as hard -
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.
Ball Mill Bond Work Index. Bond Rod Mill Grindability Test. Grinding Solutions can carry out Bond Rod Mill Work Index tests to determine the energy requirements for milling ore in a rod mill. The test requires a minimum of 20kg of -12.5mm material. Closing screen sies typically range from 4.75mm to 212m. Get Price List Chat Online
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 ...
In this scientific study, the objective is to determine the Bond work index of a given ore. A given ore was prepared by stage crushing and grinding, and underwent feed size analysis. After which, the ore was grinded in a ball mill until a 250% circulating load was achieved.
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 ...
Bond ball mill work index: Figure 2: Ball mill for determining Bond ball mill work index 1 For the purists, there were two models in existence at the time: the Von Rittinger and Kick models. Neither of these gave results that matched the observations of specific energy consumption from tumbling mills.
XMGQΦ305 Grinding Work Index Ball (Rod) Mill . Description; 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 …
What Is Bond Ball Mill Work Index. As a leading global manufacturer of crushing equipment, milling equipment,dressing equipment,drying equipment and briquette equipment etc. we offer advanced, rational solutions for any size-reduction requirements, including quarry, aggregate, grinding production and complete plant plan.
Bond(1952) E=CB(1 x2-1 x1) or dE dx =CB 1 x3/2 or EB=W1(10 x2-10 x1) where x 1, x 2: top particle sizes before and after, or the sieve sizes in μm through which 80% powders in the feed and product, respectively. W 1: Bond work index e.g. W I=9.45kWh/ton for bauxite =20.7 for coke from coal =8.16 for gypsum rock In general, dE dx =-C xN where N ...
The goal of this work is to create an equation to adjust a Bond ball mill work index from one P 80 basis to another. The proposed model consists of two components, the variable coefficient that is determined from a specific work index determination and a fixed exponent determined by a …
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.
The reason for this variation in ball mill work index is because the ore at Mt. Milligan has an intrinsic exponent of –0.45 in the 100 µm to 200 µm size range, not the –0.50 exponent empirically measured by F. Bond. The work index increase between 100 µm and 76 µm is due to a porphyritic grain size that causes a spike in energy
The Bond ball mill work index is one of the most commonly used grindability tests in mining, and is often referred to as the Bond work index. The test is a 'locked-cycle' test where ground product is removed from test cycles and replaced by fresh feed. The test much achieve a …
EURASIAN MINING • 1. 2015 Technology and technics of ore preparation processes 7 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.
Bond Work Index An Overview Sciencedirect Topics. The ball mill work index laboratory test is conducted by grinding an ore sample prepared to 100 passing 3.36 mm 6 mesh to product size in the range of 45-150 m 325-100 mesh, thus determining the ball mill work index Wi B or BWi.
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 and the ball mill.
The ability to simulate the Bond work index test also allows examination of truncated ball mill feed size distributions on the work index. For grinding circuits where the feed to a ball mill is sent directly to the classifier and the cyclone underflow feeds the ball mill (see Figure 3.10), a question arises as to whether this practice will alter the ball mill work index (BW i) of the material ...
In ball milling, the Bond ball mill work index can be used to determine specific energy at a range of feed and product sizes. The Bond top size ball formula can be used to estimate the media size required. No such standard formulas exist in fine grinding.