Density

DENSITY DETERMINATION

SGS uses the latest state-of-the-art technology through nuclear depth density gauges. The probe source is a radioactive material that emits gamma radiation at a constant average rate. The gamma rays interact at the atomic level with the surrounding medium. The number of interactions, or scattering events, per unit time is a function of the density of the sample.

The variation in chemical composition of the different coal sources represented in most stockpiles requires calibration of the nuclear depth gauge. This allows a representative sample of coal in each stockpile. Once the nuclear gauge is calibrated to the coal, a borehole is made and access tubing is inserted. The nuclear probe is then lowered into the stockpile via the access tubing and readings are taken at pre-determined depth intervals. These are recorded for use in the pile density calculation.