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PREPARATION
Title: SENIOR SCIENTIST
Phone: () -
IMPROVED PROCESSES ARE SOUGHT FOR DEASHING AND DESULFURIZING COAL. THIS INVESTIGATION WILL FOCUS ON ULTRASONIC EFFECTS ON FINE PARTICLE SEPARATION OF COAL FROM ASH, PYRITE AND LIKE MINERAL MATTER AFTER GRINDING. COAL ORGANIC MATTER, INCLUDING SULFUR CONTAINING ORGANICS, HAS A SPECIFIC GRAVITY OF LESS THAN ABOUT 1.6. CLAYS AND MINERALS FROM OVERBURDEN HAVE SPECIFIC GRAVITIES BETWEEN 2.4 - 2.8, WHILE THE SPECIFIC GRAVITY OF PYRITE IS ABOUT 5.0. HENCE, CONVENTIONAL COAL CLEANING PLANTS USE SPECIFIC GRAVITY TO EFFECT REMOVAL OF CLAYS AND PYRITE. MANY COALS CONTAIN PYRITE AND MINERALS WHICH ARE OF SMALL PARTICLE SIZE AND WIDELY DISPERSED. SPECIFIC GRAVITY WILL NOT BE EFFECTIVE IN REMOVING WIDELY DISPERSED PYRITE. THE CYCLIC VIBRATORY MOTION OF A PNEUMATIC MEDIUM INFLUENCES SUSPENDED DISCRETE PARTICLES TO A VARYING EXTENT. AT ONE EXTREME, WHEN THE PARTICLES ARE VERY SMALL AND/OR THE FREQUENCY IS LOW, THE PARTICLES VIBRATE IN PHASE WITH THE MEDIUM AND AT THE SAME AMPLITUDE. AT THE OTHER EXTREME, WHEN THE PARTICLES ARE VERY LARGE AND/OR THE FREQUENCY IS HIGH THE PARTICLES REMAIN STATIONARY. AS THE FREQUENCY IS INCREASED, THE LARGEST PARTICLES ARE THE FIRST TO LAG BEHIND THE VIBRATION OF THE MEDIUM AND, FINALLY, TO STOP VIBRATING. INCREASE OF FREQUENCY FURTHER LIMITS THE SIZE OF PARTICLES RESPONDING, THE SQUARE OF THE LIMITING PARTICLE DIAMETER BEING INVERSELY PROPORTIONAL TO THE FREQUENCY. IN THIS PROJECT, ULTRASONIC EFFECTS ON ENTRAINMENT AND SEDIMENTATION AS A FUNCTION OF PARTICLE SIZE, DENSITY AND SHAPE WILL BE ANALYZED. AFTER FINE GRINDING COAL PARTICLES REMAIN MORE EQUIAXED THAN ASH CONTENTS WHICH ASSUME A PLATE-LIKE SHAPE. WHEN INTRODUCED INTO A GAS STREAM IN A TUBULAR REACTOR AND EXPOSED TO ULTRASONIC STANDING WAVES THESE DISSIMILAR PARTICLES WILL SEPARATE BECAUSE OF DIFFERING SIZE, DENSITY AND SHAPE THUS ENABLING EASY COLLECTION. THE TWO PRODUCTS WILL THEN BE ANALYZED BY EXISTING METHODS SUCH AS WASHABILITY AND SUBSEQUENT PROXIMATE ANALYSIS TO DETERMINE THE SEPARATION EFFICIENCY OF THE TECHNIQUE. THE PHASE I FEASIBILITY DEMONSTRATION SHOULD PROVIDE THE NECESSARY ENGINEERING DATA FOR FURTHER PHASE II AND III DEVELOPMENT OF PRODUCTION ARRAYS.
* Information listed above is at the time of submission. *