A method of grinding a mineral-containing ore, which includes grinding the mineral-containing ore in a primary milling process and thereafter fine grinding the mineral-containing ore in a secondary ball-mill. A composite grinding medium comprising a mixture of steel balls and pebbles is used in the secondary ball-mill. The pebbles have an average size which is …
A quick procedure with two grinding cycles for the determination of the Bond. work index approximate value is exactly the same as in the first two …
Table of Bond Work Index by Minerals. Post navigation. Previous. Next. 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 Bond work index determination according to the standard Bond's test is done on all these samples with compara-tive sieve size of 74, 105 and 150 microns. The Bond Work Index is calculated using the formula (Bond, 1961): (√ √) (1) where: W i – Bond work index (kWh/t); P c – test sieve mesh size (µm);
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 …
Table 4 shows the Bond work indices for some minerals and industrial materials from [25]. Note that the real circuit mills present work indices greater than those in laboratory tests, in a typical ...
Average annual production of 303,000 ounces of gold over a 10.3 year life of mine within proposed pit shell; ... Bond Rod Work …
Testwork: Bond abrasion index SAGMILLING. Test name: Bond Abrasion Index Abbreviation Alternate Forms Ai Typical F 80 size Typical P 80 size 19 000 µm n/a Models: Steel wear calculation The Bond Abrasion Index is a measure of how readily a rock sample will wear away steel that comes into contact with it.
Determination of Bond Index of Wasagu Manganese. ABSTRACT. the grinding power required for a given throughput of material under ball mill grinding consitions JKTech Pty, A Bond Ball Mill Work Index test may be required for the design of a, sample of ore that is typical of the proposed feed to the plant.
A Bond ball mill work index is then performed on the mill product for the design of SAG-ball mill circuits. This is important because it was found that there was a 1–1.5 kWh/t higher ball mill work index if the –3.35 mm ball mill test feed size is obtained by SAG mill grinding compared with crushing.
Here is the old Allis-Chalmers Bond Work Index Grindability Test Procedure. The standard feed is prepared by stage crushing to all passing a 6 mesh sieve, but finer feed can be used when necessary. It is screen analyzed and packed by shaking in a 1000-cc graduated cylinder, and the weight of 700 cc is placed in the mill and ground dry at 250 ...
Bond Work Index Tables (Wi) - Free download as PDF File (.pdf), Text File (.txt) or view presentation slides online. Here there are given tables from various sources for the Bond work index values of mining materials (ores, industrial minerals and rocks). These work indexes can be used for the determination of tumbling mills (rod, ball mills ...
FIGURE 6: BOND BALL MILL WORK INDEX v. UNCONFINED COMPRESSIVE STRENGTH 0 100 200 300 400 UCS (MPa) 5 10 15 20 25 30 WiBM (metric) Figure 6 displays the plot of ball mill Work Index (Wi BM) versus UCS. Still no relationship is observed.
Results from the Program will be used by the Company to advance La Negra along the path towards an initial mineral resource estimate and a preliminary economic assessment (PEA). Work will include: Sample characterization including QEMSACN mineralogy. Bond Ball Work Index test and grind calibration testing.
• The following average gold grades were determined for the three composites: Composite 1: 6.6 g/t, Composite 2: 16.7 g/t, and Composite 3: 11.4 g/t. • The Bond Ball Work Index ranged between 15.7 and 16.8 KWh/metric tonne Outotec concluded that sufficient data was generated from the test to support a conceptual
Abstract. 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 resistance of material to ball milling. This happens after 7–10 grinding cycles, which shows that the procedure is a lengthy and complex one and is therefore ...
1.. IntroductionA 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 for grinding, …
From an ore hardness and comminution perspective, the majority of South Australian magnetite ores have a rock strength classified as soft to medium with Bond crushing work index (CWi) values typically 10–20 kWh/t, abrasion index (Ai) values 0.2–0.6 (majority <0.5) and Bond ball mill work index (BWi) values 11–19 kWh/t.
Bond's approach consists of determining the ore hardness characteristics, or Work Index (Wi) via standardized laboratory testwork. The full suite of Bond comminution tests provide the Ball Mill Work Index (BWi), the Rod Mill Work Index (RWi), the Crusher Work Index (CWi) and the Abrasion Index (Ai).
Wi = The Bond Ball Mill Work index ( 1952 )- is a measure of the resistance of the material to crushing and grinding . A Bond Ball Mill Work Index test may be required for the design of a new mineral processing plant . It is determined by Bond Ball Mill Grindability test in a lab using a Bond Mill.
Table of Bond Work Index by Minerals. Mar 19,, 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, Basalt, 189, 171, 188, 190, 190, Concentrator Manuals/Procedures Crushing & Screening Dewatering Equipment Feeders.
Bond Ball Mill Work Index, BWi, kWh/t 13.4 Bond Rod Mill Work Index, RWi, kWh/t 18.1 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 profitability. Mill operators have long used operating ...
The actual minerals are rarely used, particularly diamond, as it is expensive to procure. For instance, a fingernail is often used to represent hardness scale 2.5 and a steel file for 6.5. The testing process involves starting at the soft end of the scale and working through until one of the minerals/materials leaves a permanent indentation.
the work index depending on the grind size. In this way, work index values are usually obtained for some specific grind size that characterizes the grinding operation to design or under evaluation. This study was carried out in a standard bond ball mill 305 mm x 305 mm size in mineral processing laboratory, in the mining engineering department ...
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 ...
SMC Data Processing. The results from conducting the SMC Test® are used to determine the drop-weight index (DWi) which is a measure of the strength of the rock as well as the comminution indices Mia, Mih and Mic. In conjunction with the Bond ball mill work index they can be used to accurately predict the overall specific energy requirements of ...
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 work index (Wi) is calculated in a laboratory-scale ball mill with Bond equation. The Bond work index has been widely used in designing full-scale mills but the Bond test is rather complex, lengthy susceptible to procedural errors and this is why attempts have been made to abbreviate and simplify Bond test procedure ( Weiss, 1985 ). 2.
Gangue minerals include dominantly plagioclase and quartz along with sericite/muscovite, K-feldspar, and carbonates. Comminution: Bond Ball Mill Work Index (BWI) testing was performed on nine samples. The indices varied from 16.9 to 20.6 kWh/t, with an average of 18.6 kWh/t.
others in Allis-Chalmers have developed a grinding test in a ball mill in a closed cycle until the establishment of stable recirculating load (Maxson et al., 1933). The Bond work index is a parameter which represents a measure of an ore resistance to grinding. Numerically, the work index represents the energy (kWh/sht)
حقوق النشر © 2024.Artom كل الحقوق محفوظة.خريطة الموقع