Latest Developments of X-ray-Transmission-Based Sorting for Coal

摘要

Coal sorting with an x-ray-transmission (XRT) sensor has experienced a lot of development since first described by Bloomfield and Slight in 1966. Powerful computers and increasingly sensitive X-ray scintillation counters enabled the development of high-performance sensor-based sorting machines with up to 2.4m working width. The first industrial installation of a belt-type XRT-sorting for coal is in operation since 2004. It is upgrading high quality coal from 1% ash to 0.7% ash for cathode production. Since 2010 chute-type sorters are in operation in South Africa for destoning of raw coal and have been used for extensive test work. Improvements on both separation efficiency and availability of containerized semi-mobile systems have been achieved. The article will introduce the principle of the technology and will summarize the latest experiences in both separation efficiency and operational stability. In addition to containerized semi-mobile installations it introduces the plant layout of a stationary plant with 1,200tph plant capacity.