Preparation Plant Control Using on-Line Ash Analyzer

The application of on-line ash analyzers in coal processing has become widespread. However, the analyzers are employed largely in monitoring, blending or sorting applications. Just recently has work begun on using on-line ash, moisture and/or solids data for plant control; and even more recently for localized circuit or unit operation control. Process Technology, Inc. (PTI) has since 1990 placed several bulk coal and slurry analyzers in practice where Fuzzy Logic Control (FLC) loops are used to manipulate controllable variables in real time. This technology is now being advanced by PTI. Unit operations where FLC has been employed in feedback loops using on-line ash analyzers include: heavy media vessels, cyclones, concentrating tables and froth flotation. The design, implementation and improvements attainable in preparation plant control using on-line ash analyzers are outlined in this paper.