Scantech International Pty Ltd designs, manufactures and supplies analysers for measurement of conveyed coal utilizing various technologies depending on the parameter to be measured. The COALSCAN range of ash, moisture and elemental analysers has been on the market for over 35 years and continues to expand.
Initially the company was focused on commercializing dual-energy transmission technology for ash measurement in the early 1980s. With hundreds of installations this was and still is a very robust design with some units installed in the 1980s still operating. The COALSCAN 2100 ash analyser typically achieves accuracies of better than 1% ash. Main applications are measuring raw coal feed to wash plants and washed coal quality. The COALSCAN 1500 uses natural gamma sensing to calculate the ash content of coal without the use of radioactive sources as in the COALSCAN 2100.
Moisture analysis is commonly used in conjunction with ash analysis to enable calculation of heating value of coal. TBM systems utilize microwave transmission technology to detect free moisture by measuring the attenuation and group delay of microwaves passing through the conveyed coal. A signal from a belt weigher is used for the total mass flow and the TBM determines the moisture content to accuracies better than 0.5% moisture. Moisture measurement can be used to monitor TML, assist with optimal filter or dryer operation, and for dust management.
In some cases more detailed information on coal quality, such as sulphur content and other ash components is also needed, particularly for thermal coal where power stations may require coal with strict composition requirements.
The COALSCAN 9500X has been used to provide accurate elemental analysis on full flows rather than sample streams which may not be representative. A chute-based version has also been supplied where opportunities to measure have been limited by high chlorine content in conveyor belts or space has been limited on existing belts. Measurement accuracy is typically close to 0.5% ash.
The latest models use a common interface and include remote access capability. All models measure through the full bed depth continuously and provide results second by second or minute by minute. Scantech analysers are considered a premium product due to high specification, robust design and comprehensive shielding particularly for the PGNAA based COALSCAN 9500X which requires no additional isolation area around the unit.
Recent comparisons to other products on the market by a customer indicated the COALSCAN 9500X had one quarter the radiation levels of a newer competitor product claiming to be the latest and most advanced system in the market with a smaller source, but evidently also much less shielding. No two products in the market are the same so a thorough due diligence process involving reference checks should be considered in all purchasing decisions.
Scantech’s latest addition to its range is the SizeScan PSD (particle size distribution) analyser developed by COREM in Canada and commercialized by Scantech. It is a next-generation PSD system using a 3D infrared camera and advanced algorithms that overcome known problems in particle recognition using segmentation software. The 3D IR camera is unaffected by dust and lighting controls required for traditional 2D digital camera systems which add significantly to installation and operating cost and maintenance of those systems. SizeScan has the added advantage of reporting every five seconds the conveyed volume and belt speed with the PSD data. Where bulk density is consistent the SizeScan becomes a reliable mass flow measurement device compara­ble to a nucleonic weigh scale in performance. SizeScan does not require ongoing calibration or support, unlike other measurement systems.
Scantech offers various installation services. Installation manuals are available to clients wishing to install equipment themselves. Installation supervision, engineering, fabrication, or full turnkey options are also available. This limits risk of cost or schedule blowouts and ensures analysers are installed correctly the first time, every time. Clients have analysers operating sooner and providing benefits in the shortest possible timeframe after purchase.
Ongoing service and support for analysers is handled by qualified service engineers based near concentrations of analyser installations in Europe, Africa, Asia, Australia, North America and Latin America. A central pool of engineers provides support as needed for commissioning and calibrating analysers as well as R&D.