Fine coal washability analysis using a laboratory concentrating table: G. William Kalb undergraduate research fellowship project report

Coal washability (float-sink) analysis uses heavy liquids that are a health hazard. In addition, for fine coal (-1 mm) especially, a problem with contamination by the heavy liquids arises as these fines are exposed to these chemicals for a longer time, to affect the separation. Laboratory-scale gravity concentration equipment is available to separate narrow size fractions of coal to develop washability data for a particular size fraction. This project evaluated a laboratory concentrating table for this purpose. Concerns over the validity of the initial float-sink testing limited the validation of its application in the first year of the project. Results in the second-year show promise for the use of the concentrating table, especially when comparing yields at a 10% ash level, which is typical for many US thermal coals. This paper reports on the initial findings from an undergraduate research project sponsored by the Coal Preparation Society of America.