Evaluation, engineering and development of advanced cyclone processes. Quarterly technical progress report No. 15, April 1, 1994--June 30, 1994

The project goal is to develop an advanced coal beneficiation technology that can achieve high recovery of the parent coal`s calorific value, while maximizing pyritic sulfur removal. Coal cleaning is to be accomplished by physical means incorporating an advanced form of cycloning or gravimetric process. Evaluation of different media types and their attendant systems for recovery, concentration, and regeneration is to be completed. Phase I, media evaluation, now completed involved a paper study and a number of laboratory tests to eliminate all but the best media options. Phase II, media testing, involved detailed testing of the more promising media and separators in a closed-loop pilot facility circuit. In the final phase, Phase III, it is proposed to test individual components of the process using the optimum medium, separator, and medium recovery systems(s) selected in prior phases. Some of the highlights for this reporting period are: (1) Outomec conducted a second set of hot water wash experiments. These hot water experiments, using prefiltered medium, yielded a significant improvement in calcium nitrate recovery, and showed a consistent decrease in residuum calcium nitrate with increasing wash rate. (2) Several alternatives were investigated for potential reduction in thermal regeneration process costs. Culligan, Spin Tek, and Rochem, manufacturers of reverse osmosis or ultra filtration systems were contacted. Rochem ultimately performed laboratory experiments. Starting with a dilute medium density of 1.07, the Rochem laboratory system achieved a density of 1.11. A density of 1.22 sg would be commercially attainable. This is less than the target medium density of 1.35, meaning that if their system were utilized, some thermal means would still be required to regenerate medium to operating density. (3) Management and Technical Systems initiated work on a preliminary economic study and will submit a report during the next quarterly reporting period