GSL offers the following tests for SAG mill testing and/or sizing.
JKTech Drop Weight
The JKTech Drop-Weight Test measures the breakage characteristics of an ore for five size fractions in the range of 13 to 63 mm, at various energy inputs (0.1 to 2.5 kWh/t). The ore-specific parameters derived from these measurements can be used in grinding circuit modelling and simulation. In combined with other inputs such as a Bond ball mill work index, they enable simulating the response of a flowsheet to ore and process variability. The simulation can also be used when designing new circuits and in equipment selection.
The test requires a minimum of 75 kg of <100mm ore.
SAG Mill Comminution (SMC) Test®
The SMC Test® is conducted on a single size range which is typically -31.5 mm +26.5 mm, hence the sample requirements are less than drop weight test.
The test generates the Drop Weight Index (DWI) which is expressed in KWh/m3, which strongly correlates to values generated from a Drop Weight Test.
The sample requirements depend on which size fraction is selected for the test. 5kg of material in the test size range is required for testing. Assuming a test size of between 31.5 mm and 26.5 mm, 30 kg of ore is generally sufficient.
SAG-mill Power Index® (SPI) Test
The SPI® test is carried out in a standardised mill under set conditions, with the output being the time to reach a given size, which can be converted to a SAG mill specific energy input (in kWh/t).
The SPI® index provides a profile of the hardness of the ore type and can be used for geometallurgical models. The data can be used for the sizing of AG and SAG mills.
The test requires a minimum of 2kg of ore passing ¾” (19.1mm) with no more than 80% passing ½” (12.7mm).