BOND'S WORK INDEX: WHAT IT IS AND WHAT IT ISN'T
Bond's work index model of quantifying mineral grindability was born out of the desire for a better way of scaling up laboratory grindability test results to industrial-scale grinding mills (Lynch & Rowland, 2005). The Allis-Chalmers company (now ) collected a great deal of operating and laboratory data during the 1930s
Grindability, a test worth taking | American Machinist
Guided by test results, Timken Latrobe Research in Canton, Ohio, then works its metallurgical magic to produce material grades more consistently and with improved grindability. "For some grades," says Jim Maloney, manager of steel product development at Timken, "we have upped grindability by as much as 10%."
Test The Grindability of Your Favourite Elements
The right mineral and metallurgical testing procedures like grindability can help determine the right equipment for large scale projects. To learn more about the metallurgical testing services we offer, and how they can make an impact on your projects, contact Sepro Labs at 1-604-888-7604.
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 general, the …
Why is the Bond Ball Mill Grindability Test done the …
Although the Bond Ball Mill Grindability Test has existed for more than 40 years, there is little information which explains why the test is done the way it is done. Questions about the Bond test include: Why is the test a locked-cycle grinding test? E-mail: [email protected]
Amex Exploration Announces Metallurgical …
Comminution Test Work. Bond Ball Mill Grindability Test. The bond ball mill grindability test was completed on each of the eleven samples. A summary of the test results is presented in Table 3. With bond work index …
The SAG grindability index test
Analysis of a data set of approximately 150 tests conducted using the SGI mill indicate that it is possible to produce a lower cost, lower precision version of the SGI test by performing a single grinding iteration with the standard feed charge for a constant time interval of 60 min.The resulting product is then screened on a Tyler #10 mesh screen (1.7 mm) and an …
Improved grindability and gold liberation by microwave pretreatment of
In addition to the enhanced grindability, gold was released from the matrix of the host minerals at a coarser size, resulting in a significant increase in free gold recovery by gravity ...
Indicators of grindability and grinding efficiency
For the answer, the paper presents averaged values for the standard grindability indices of the gold ores of the Wrtwatersrand, averaged values for the performance of grin
Geometallurgical characterization of South Georgian …
grindability test (Bond, 1961). Chemical and mineral composition of the ore types The copper and gold contents of the six samples range from 0.28 to 0.77% Cu and 0.19 to 0.75 ppm Au. The main copper minerals are chalcopyrite, and chalcocite-group minerals, which have the general formula Cu 2-x S and include chalcocite, digenite,
Why is the Bond Ball Mill Grindability Test done …
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 …
Standard Grindability Tests and Calculations
Standard Grindability Tests and Calculations (New York Meeting.February 1943) SINCE the last publication of tabulated results of grindability tests by the authors1 the total number of ball-mill tests made
Conduct and precision of bond grindability testing
The Bond rod mill grindability test is a widely used tool to estimate the response of ores to rod milling. However, the mass of ore required to conduct the test, which can typically vary from about 8 to as much as 20 kg, may represent a challenge when sample availability is critical. The present work proposes an alternative procedure, which is ...
Results of the Bond grindability test
Grindability measurement as a testing method can be divided into two general categories; the Bond (Gbg) and the Hardgrove grindability index (HGI). ... The variation of gold ore petrography ...
Indicators of grindability and grinding efficiency
Bond grindability test mill is 198 x 10-7kWh. (Equivalent energy consumption is the energy per tonne of product that would be used in a mill of diameter 2,44 m grinding wet with a circulating load of 250 per cent An example of the calculation is shown in Table I. The Bond standard grindability test is well known and
A public Database of tumbling mill grindability …
Collecting and comparing these published grindability measurements provides a basis for basic research, such as calibration of specific energy models, and for benchmarking new projects.
Bond Ball Mill Grindability Test Summary
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 ...
Testwork: SAG grindability index
The SAG Grindability Index (SGI) test, or alternatively the trademarked SAG Power Index (SPI), is a SAG-specific test involving a small batch SAG mill that is charged with a two kilogram ore sample and ground until the product has achieved an 80% passing size of 1.7 mm. The test result is reported as time required to achieve the target product ...
Geometallurgical characterization of the Kittilä gold ore …
the grindability and crushability properties of six different ore types from the Kittilä Au deposit in Northern Finland. In summary, the tests which were conducted for this study include the Bond Ball mill grindability test, the Los Angeles abrasion test, the Point Load Strength test and the JK Drop Weight impact test.
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 ...
An Overview Of the SmAll-ScAle teStS AvAilAble tO …
Several grindability tests, at various scales, have been developed over the years for different applications, from conventional circuit to autogenous grinding, and they all have strengths and …
Methods for Estimating the Bond Work Index for Ball Mills
The proposed grindability test for fine materials indicates the specific energy required to grind a given material from its initial size to a given size. ... Powell, M.S. Benchmarking comminution energy consumption for the processing of copper and gold ores. Miner. Eng. 2014, 65, 109–114. [Google Scholar] Babu, S.P.; Cook, D.S. Breaking ...
(PDF) Evaluation of gold ore properties and their impact on …
Purpose. The purpose of this paper is to evaluate the efficiency of grinding operations in terms of how mechanical properties (e.g., strength properties and ore texture) affect the Bond Work Index.
A Statistical Comparison of Bond Ball Mill Grindability Work …
The commonly used grindability tests included in the database are the Bond work indices for ball milling, rod milling and crushing; the drop weight test results A, b, A×b, DWi, Mia, Mic, Mih and ...
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 …
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 …
A Review of Alternative Procedures to the Bond …
Over the years, alternative procedures to the Bond grindability test have been proposed aiming to avoid the need for the standard mill or to reduce and simplify the grinding procedure. Some of ...
COAL PHYSICAL TESTING
The Hardgrove Grindability test is a measure of coal's resistance to crushing and attempts to reproduce the effects of continuous coal pulverization in a mill. A 50-gram sample of prepared coal of uniform size range is placed inside a grinding unit. The unit undergoes a
Standard Grindability Tests and Calculations
Table I gives the condensed results of 374 standard ball-mill grindability tests. Those for each mesh size are arranged in the order of increasing ease of grinding, so that the list for any mesh constitutes an as- cending graduated scale of grindabilities.
A RAPID SAG MILL GRINDABILITY AND MILL SIZING …
designed a test work and reporting procedure which focused on delivering the highest quality SAG grindability results in the shortest period of time. The full program was executed in six weeks from preliminary work to final reporting. This was possible thanks to the global test quality control conducted on SAGDesign tests which allowed work to be