AUTOMATIC SORTING AND CONTROL IN SOLID FUEL PROCESSING: OPPORTUNITIES IN EUROPEAN PERSPECTIVE

(8 fi gures and 2 tables) ABSTRACT. On-line automatic inspection of solid fuel has been known for several decades and continues to develop. Automatic sorting of solids is currently applied in upgrading a variety of resources and wastes: ore, recycle glass, scrap metals, plastics, and foods. Inspection and sorting use the same technology for both coal and refuse derived fuel. Sen- sors inspect a fl ow of solids and a particular fraction is successively manipulated, e.g. by reject of a particular load or by automatic removal of contaminants by means of controlled air jets. Applications are: • On-line ash and particle size control of coal • Automatic dry cleaning • Automatic control and reduction of contaminants Transmission theory and experiments carried out at Delft University illustrate the potential of dual-energy X-ray transmission imaging for the on-line determination of ash content and size distribution of bituminous coal. Based on this technology and combined with existing methods, sensor controlled sorting systems may in future be applied as cost-eff ective methods for control and improvement of the quality of solid fuel.