AshScan® Online Coal Analyzer
The AshScan® Online Coal Analyzer provides realtime, continuous data on total ash content in coal. Using DUET (duel energy transmission) technology, also known as LET (low energy transmission), the AshScan® is a tried and proven performer suitable for most coal types. Ash consists mainly of oxides of silicon (Si), iron (Fe), aluminum (Al) and calcium (Ca). The AshScan® measures the combined total of these elements which directly correlates to the total ash content in coal. The DUET technique uses two radioactive sources; Am-241 and Cs-137. Am-241 is a low energy gamma radiation. Absorption of Am-241 gamma rays occurs due to the presence of Si, Fe, Al and Ca, and the amount of coal on the belt scale. Cs-137 is a high energy gamma radiation. Absorption of Cs-137 gamma rays is due only to the amount of coal on the belt scale. This allows the Am-241 measurement to be normalized for bed depth. The normalized Am-241 absorption is then correlated to total ash content by calibrating against laboratory reported ash sample results. The AshScan® is suitable for both raw coal and washed coal where ash chemistry is relatively stable and where the bed depth of the coal does not exceed 14 inches. Its practical design incorporates many unique features not available in other through belt ash gauges. The AshScan® on-belt coal analyzer’s modern electronics, communications and human machine interface makes set-up, calibration and ongoing verification of accuracy simple and straightforward. The AshScan® is commonly used in the coal and power industries for:
- Quality Control
- Metallurgical Accounting
GammaScan® Non-Nucleonic Coal Analyzer
The GammaScan® non-nucleonic coal analyzer, measures total ash in coal, in real time, on a conveyor belt. As such, it does not require a radioactive source. Ash content is calculated by measuring changes in natural background radiation emitted by coal.
Gamma radiation is predominantly emitted by elements uranium (U), potassium (K) and thorium (Th) which are naturally present in coal. The amount of these elements correlates strongly with the main ash forming elements silicon (Si), iron (Fe) and calcium (Ca). By measuring the gamma count rate ash content is accurately determined.
The GammaScan® incorporates a large scintillation detector which is mounted between conveyor idlers directly under the center line of the belt. This detector is shielded from background radiation by a lead lining within the detector assembly, as well as an over belt lead shield.
This technology is ideally suited to the measurement of ash in applications with thick coal beds such as run-of-mine, raw coal conveyors and plant feed conveyors. The natural gamma technology is the only technology that can measure bed depths that are more than 14 inches.
The GammaScan®, like all RTI online analyzers, combines advanced technology with field know-how. The result? A state-of-the-art online coal analyzer that is easy to install, easy to calibrate, and practical to service. The GammaScan® is commonly used in the coal industry for maximizing coal recovery.
