Characterization and Comminution Studies of Low-Grade Indian Iron Ores

A higher Bond work index value was found for the BHJ ore (15.4 kWh/ton) than for the BHQ ore (12.4 kWh/ton). A decrease in the product particle size was associated with an increase in the work index value. ... Characterization studies play an important role in the processing of ores. These studies help to identify the major and …

Bond´s work index estimation using non-standard ball mills

It is a well-known 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 ...

-Average surface bulk temperatures and …

The largest decrease, i.e. improvement, in the work index (by 13%) occurred for the ore 2, which was heated up to 608ºC as seen in Table 1. It should be noted here is that the reproducibility of ...

Metallurgical Test Work: Gold Processing Options, Physical Ore

1. Background. For the past 100 years, the key element in the processing of gold ore has been the cyanidation process.Over the years, steady improvements have occurred in equipment design; milling has evolved from stamp mills, through tube mills and ball mills to the large semiautogenous grinding (SAG) and fully autogenous grinding …

Indicators of grindability and grinding efficiency

indices provide the same information as the Bond indices; whether one type of index is more accurate or more useful than the other; whether there are limitations to the ~s indices similar to those to the Bond Wi indices. Information on these questions is presented here from work done on Witwatersrand gold ores. However, the principles relating

Effect of mineralogy on grindability – A case study of …

1 contained more than 80% (w/w) of quartz compared to about 70% in the other two ores. The Bond work indices were 13.8, 21.6, and 17.3 kWh/t for sulphide 1, sulphide 2, and oxide ore ... Figure 1—A typical copper deposit hosted by an arkosic sandstone, featuring three mineralization zones. The arkosic sandstone is dominated by quartz,

Compare and Understand Rod/Ball/Impact …

Anyone wondering how Bond ball mill work index compares versus SPI or JK A*b? Well, M. Doll says, several comparisons have been published, such as at CMP 2011 and Procemin 2009 and in …

Bond Work Index

Berry and Bruce (1966) developed a comparative method of determining the hardness of an ore. The method requires the use of a reference ore of known work index. The …

(PDF) Variability Study of Bond Work Index and …

Abstract and Figures. It is a well-known 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 ...

(PDF) Alternative Approaches for Determination of Bond Work Index …

The brittleness indices of the ores were calculated using the chemical composition of the gangue, and a good correlation between brittleness indices and Bond work indices was observed, which ...

Geometallurgy—A Route to More Resilient Mine Operations …

Geometallurgy is an important addition to any evaluation project or mining operation. As an integrated approach, it establishes 3D models which enable the optimisation of net present value and effective orebody management, while minimising technical and operational risk to ultimately provide more resilient operations. Critically, …

Ball Mill Design/Power Calculation

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 …

Correlation Between Bond Work Index and Mechanical Properties …

Indices with which the crushing resistance or the grindability in a wide meaning is expressed include the Rittinger number, crushing resistance, Hardgrove index and Bond work index. The Bond work index is regarded as one of the crushing resistance; it can therefore be presumed that the Bond work index is correlated to the mechanical …

Grinding of Australian and Brazilian Iron Ore Fines …

Oxidised pellets have become an indispensable high-quality charge for blast furnaces. Nevertheless, high-quality pellet feeds are becoming scarcer and scarcer. To broaden the range of sources of …

EFFECT OF OPERATING VARIABLES ON BOND'S WORK INDICES …

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 ...

Table of Bond Abrasion Index for Varied Minerals-Materials

The Bond Abrasion Test determines the Abrasion Index, which is used to determine steel media and liner wear in crushers, rod mills, and ball mills. ... Ore Laboratory Testwork. Comminution Testing; Mineral Liberation; Gravity Concentration Testing; ... Prev Previous Bond Abrasion Index VS Mohs Mineral Hardness Scale. Next Copper Flotation ...

Characterization and Bond Work Index Determination of …

The bond work index test obtained high work index 52.60 kw.h/t and consumed power 11.72 kw.h/t to grind one ton of low grade iron ore and this attributed to the high concentration and hardness of ...

A New Approach to the Calculation of Bond Work Index …

Grinding media influence the energy consumption and efficiency of the grinding process during the calculation of the Bond Work index (BWi), a well-known method for selecting comminution equipment, evaluating milling efficiency, and calculating required milling power. Traditional grinding tests often choose steel balls as the grinding media, but …

AMIT 135: Lesson 7 Ball Mills & Circuits

Work Index. Bond estimated the amount of wear in terms of kilograms per kWh based on the abrasion index, A;, i.e., Wet Ball Mill = kg kWh = 0.16(A i-0.015) 0.33; Dry Ball Mill = kg / kWh = 0.023A i 0.5; Replacement Ball Size. Rowland and Kjos proposed the use of their equation for the determination of the initial and replacement media size.

Hardgrove grindability index and approximate work …

Knowing the average Hardgrove index, a calculated work index of 12.88 kW/STPH was estimated using Aplan's empirical formula. This average work index was less comparable to those of feldspar ores given in the literature. Therefore, the method of Berry and Bruce was used to determine the specific energy and approximate work index.

Variability Study of Bond Work Index and …

It is a well-known fact that the value of the Bond work index (wi) for a given ore varies along with the grinding size. In this study, a …

Summary of results from Bond crushability and impact load cell …

The traditional Bond work index proposed by F.C. Bond over 60 years ago is still today a useful tool for characterizing material crushability and grindability in the minerals industry.

Secrets of the Bond Ball mill grindability test

The Bond ball mill grindability test is one of the most common metrics used in the mining industry for ore hardness measurements. The test is an important part of the Bond work index methodology for designing and measuring the efficiency of mineral grinding circuits. ... a typical feed size observed for samples prepared by stage-crushing.

Hargdrove Grindability Index (HGI) and calculated Bond work index …

Ore grindability is represented by the Bond work index value [6] and Mucsi et al. [5] have summarized the most widely known and utilized grindability tests as Bond, Hardgrove and Zeisel methods [7 ...

A new methodology to obtain a corrected Bond ball mill work index …

Copper ore samples from Canada are designated Copper ore 1, and copper ore samples from the South American meta-sedimentary copper mine are denoted as Copper ore 2 to Copper ore 6.Copper ore 1 samples represent the same sample with different values of parameters F 80, P 80 and P 100.The samples are shown in the table …

[PDF] Alternative Approaches for Determination of Bond Work Index …

PLK (Partially Laterised Khondalite) rock is a general terminology used in this paper for those rocks which are in general associated in bauxite mining such as Partially Altered Khondalite (PAK) rocks, Partially Kaolinised Khondalite (PKK) rocks and Lithomerge. This paper deals with the Bond's work index, Hardgrove index and …

Bond Work Index Procedure and Method

This Grindability Test or Bond Ball Mill Work Index Procedure is used to determine the Bond Work Index of minus six mesh or finer feed ore samples. These equation application methods are used …

Using Rock Geomechanical Characteristics to Estimate Bond …

A quick method for bond work index approximate value determination

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 ...

Prediction of Bond's work index from field measurable rock …

For the evaluation of laboratory and industrial experiments, the work index can be determined as follows: BWI = 44.5 P 1 0.23 × G 0.82 10 P − 10 F where BWI = …

Comparison of measures of rock crushability

The traditional impact work index (Wi) proposed by Fred Bond over 60 year ago is still used today in characterizing material crushability. However, more recent measures, namely the point load ...

(PDF) Comparison of the Standard Bond Procedure and a …

The Bond work index expresses the resistance of materials to milling. ... Bond and two-cycle procedures Conclusions Introduction The hardness and grinding characteristics of an ore are important in determining the power necessary for its comminution. There is also the need to estimate the energy required to grind one tonne of ore from a given ...

Comminution

The typical Bond work indices for ores processed in the mineral industry may vary through a range from below 10 kWh/t to over 30 kWh/t; the larger value indicating the more competent ore. ... Type of media (steel or ceramic) is also important in applications where contamination of product is a problem. There are three important …

Ore competence and its influence on the choice of …

The ball mill values largely followed the Bond laboratory work index results, which were also obtained for each ore type. The AG/SAG operating work indices show their usual elevated levels ...

Bond Work Index Formula-Equation

When Erf/Erp is greater than 1.29, the work index increases as the product size decreases, and when Erf/Erp is less than 1.29 the work index decreases. Eq. (8) suggests that a standard work index Wi100, …

Prediction of Bond's work index from field measurable rock …

Swain and Rao (2009) used Hardgrove index and friability value (S 1) to establish correlation with BWI of partially kaolinised khondalite (A Bauxite mine waste) and found the following correlations with correlation coefficient of 0.9348 and 0.9944 respectively: BWI = − 18.193 ln S 1 + 66.747 BWI H = 0.9982 BWI where, BWI = …

A new approach to the calculation of bond work index

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. ... Ford, E., Sithole, V., 2015. A Comparison of Test Procedures for Estimating the Bond Ball Work Index on Zambian/DRC Copper-Cobalt Ores and …

Ore Types: What They Are, How They're Made, and Their …

This difficulty in testing makes parameters like Bond work index less useful for general ore typing despite their operational importance. Once the best variables for ore typing have been identified, the data are divided into ore types by prescribing upper and lower boundaries for the most heavily weighted parameters so that no sample is outside ...