Centrifugal Float-Sink Testing of Fine Coal: An Interlaboratory Test Program

Abstract

The Pittsburgh Energy Technology Center (PETC) recently completed an interlaboratory test program (ITP) involving eight laboratories that are currently performing washability analyses of coals finer than 500-microns top size using a centrifugal float-sink technique. With the current and future development of fine coal cleaning technology, there is a growing need to determine the washability of coals in extremely fine sizes, in some cases as fine as several microns by zero. However, much uncertainty exists about limitations relative to particle size and the viability of centrifugal float-sink procedures in achieving ``ideal`` specific gravity separations (i.e, the perfect separation of particles according to their density). The objective of this work was to develop an understanding regarding the variables affecting the procedure and initiate a process for obtaining a standard procedure. (VC)