characterized as sodium feldspar. The Hardgrove grindability test used a ball-race test mill. The Hardgrove grindability indices of these feldspar samples had an average of 46.25. Knowing the average Hardgrove index, a calculated work index of 12.88 kW/STPH was estimated using Aplan’s empirical formula

WiBM Bond Ball Mill Test Work Index (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 drive pinions. 3.KEYWORDS Work Index, Work Index Efficiency, Bond Work Index testing 4.INTRODUCTION AND BACKGROUND

Dec 07, 2018 This is because work index frequently changes as a function of the product size in comminution. If target grind size during a project is changed, or if the test is run at the wrong product size, then it is necessarily to provide a correction. The goal of this work is to create an equation to adjust a Bond ball mill work index from one P 80 basis

Dec 12, 2016 Ball Mill Power Calculation Example. A wet grinding ball mill in closed circuit is to be fed 100 TPH of a material with a work index of 15

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

test using ball-race test mill was performed. Knowing the Hardgrove indices, the Bond work indices of some samples were estimated using the Aplan’s formula. The approximate work indices were determined by running a batch dry-grinding test using a laboratory ball mill. Finally, the work indices obtained from both methods were compared

Apr 19 2013 Bond ball mill work index given by the equations Table 1 shows work index and parameters of Revista de Metalurgia 42 1 pp 41–48 . effect of operational variables on ball milling Poli Monografias UFRJ

Apr 29, 2018 The Bond Ball Mill Work index test, first developed by Fred Bond in 1952, is the industry standard for sizing mills and measures the resistance of an ore to grinding. The Work Index can be used to determine the power required for closed circuit ball milling

Jan 25, 2021 Procedure for determination of ball Bond work index in the. 01.01.2009 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)

Sep 17, 2018 The work performed included analysis of operating performance data from 49 mills and included extensive determinations of the Bond Abrasion Index for different ore types. For an improved understanding, the wear rate constant is directly related to the grinding media consumption rate expressed in grams of steel per kWh drawn by the mill, using

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

Oct 28, 2021 Bond Ball/Rod Mill Work Index. Bond ball mill work index (BBMWI) test is a standard test used to measure the ball mill work, which is calculated in accordance with the procedure proposed by the Bond [21]. The BBMWI determines how much energy is needed to grind a sample of ore in a ball mill [22]

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

Ball Mill Work Index Test (BMWI), where the circulating load and the classification efficiency were systematically changed to determine their relationship on milling performance. The tests were completed in a Labtech Essa laboratory mill that

Sep 10, 2013 The Bond work index can be determined by many ways, some of them are as follows: with the traditional standard method in a (1) Bond-ball mill or in a (2) Hardgrove mill with the conversion of the Hardgrove method's result to Bond work index by an empirical formula, (3) with the more work-saving Karra algorithm (compared to the standard Bond

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

Ball mill work index adjustment. The Bond ball mill work index test requires the operator to select an appropriate screen size to close the test. The procedure states that the closing screen size should be such that the product size of the test is the same as the expected product size of the operating plant

Correction of Bond Ball Mill Work Index Test for Closing Mesh Sizes It is commonly known that one must run the Bond ball mill work index test such you pick a closing mesh to give a P80 close to desired grind size

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

Aug 03, 2021 Change Energy transfer nodes to display energy in thousand of RF. Beam more ball size is calculated in. Pictur calculation of impact and options below to work index of the spreadsheet ball mill calculation bond ball mill work by the bearing seats are nothing more detail drawing displayed

8.3.2.2 Ball mills. The ball mill is a tumbling mill that uses steel balls as the grinding media. The length of the cylindrical shell is usually 1–1.5 times the shell diameter ( Figure 8.11). The feed can be dry, with less than 3% moisture to minimize ball

mill, such as the Denver lab ball mill, to determine work index. Results obtained show that with an adequate adaptation of the methodology, especially using a volume correction factor, the

Mar 14, 2015 Use this online formula to calculate a Ball Mill, Rod Mill or SAG Mill Operating Work Index. Based on Fred Bond’s work you can estimate the energy used into your grinding circuit. This is the most accurate and informative method, but much of the data necessary for its application is not yet available. A) Total Apparent Volumetric Charge Filling – including balls

in [1]. By rearranging the formula to [2], the operating work index (Wio) of an existing grinding circuit can be calculated, given known mill power draw, throughput, feed and product size distributions. kWh/t = Power applied per ton of feed to the grinding unit Wi = The standard Bond work index of the ore P 80 = The 80% cumulative passing size

For the batch tests the mill is loaded and rotates for a time . t (sec) consuming energy (Joules). This energy corresponds to a specific energy . e = E/m (Joules/ kg), where . m. is the mass (kg) of the sample. Finally the product is wet screened to find the size . d. 80. EPt 2.3. Rod Mill Batch Process . The mill dimensions, (D L), are 0.204 0.3 m and it is

values. If the Bond work index is assumed to be proportional to the batch operating Bond work index, W. =OC:W. ｾ＠ ｾｯ＠ cc'E ( 1 1,-1.o T ｾMｾ＠ where c( proportionality constant E net specific energy provided during the batch test, (kwh/t) ( 3) If A = oe'E 10, the work index can be computed directly from A(-..! lJ -1

index in a ball mill (B BWI), which is based on a first order k inetics present in the Bond ball mill for grinding mineral raw materials (Austin et al., 1981; Ahmadi and Shahsavari, 2009)

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). The work index calculations across a narrow size range are conducted using the appropriate laboratory work index determination for the

Dec 07, 2018 This is because work index frequently changes as a function of the product size in comminution. If target grind size during a project is changed, or if the test is run at the wrong product size, then it is necessarily to provide a correction. The goal of this work is to create an equation to adjust a Bond ball mill work index from one P 80 basis