The AshScan Low Energy Transmission (LET) analyser combines state-of-the-art nuclear technology with ground-breaking modelling and powerful statistical analysis. Installed on a conveyor belt, the AshScan delivers accurate, minute-by-minute data on percentage ash content present in the coal feed from the mine enabling operators to blend coal from different seams to achieve an ash target for onward selling to consumers.
AshScan DUO in Coal Mining / Processing
The earths natural resources are becoming depleted and no more than ever there are renewed emphasis placed on using these resources more efficiently. Extending mine life, minimising waste, improving efficiency and increasing production are but a few of the challenges faced by operators of coal mines on a daily basis. Having the ability to mine, previously overseen areas where lower quality coal are present enable operators to utilise these less favourable coal and blend it with higher quality, higher cost, coals in order to achieve a pre-determined quality target. This extends the mine life whilst maintaining quality and at the same time ensure that the mine achieve it operational objectives. In order to do so operators are reliant on the provision of quality data to pro-actively direct mining operations, blend the different coal seams and maintain production rates. Sampling combined with laboratory analysis has been used for decades to achive these objectives and of late operators have realised the effect that data latency have on the operation. Timely delays in data availability, questionable representation of samples and maintenance associated with the up keep of sampling systems can be eliminated by measuring the coal ash content in real time with minute by minute reporting of this critical date which enable operators to respond quickly to changing conditions within the mining operation.
AshScan operating principle.
The AshScan utilises two radioactive sources. The technology is referred to as Dual Energy Transmission (DET) or Low Energy Transmission (LET).
LET analysers uses a Am-241 source which transmits “soft X-rays” at 60keV, which measures the density/atomic number of the ash forming elements within the coal. The higher the Ash content, the less 60keV rays will reach the detector. The second source Cs-137 transmits higher energy gamma rays at 660keV, which measures the bulk density of the coal and compensates for the bulk density and bed depth variations. If the Fe and Ca varies significantly within the coal, it will affect the accuracy of this analyser and introduce a shift in the calibration. E.g. wash plant receiving coal from 2 or 3 different mines with different Fe & Ca content. The analyser can store up to 16 different calibrations for different coal types, but it needs an input to know which coal is being feed at any given time, e.g. Coal from Mine A or B, etc. Accuracy is approx. 0.9 -1%
The AshScan has proprietary counting electronics, which is the fastest available on the market. The measurement and output has the fastest update time of less than 25 seconds.