Coal Preparation Using Magnetic Separation. Volume 4. Evaluation of Magnetic Fluids for Coal Benefication. Final Report

摘要

Research objectives were to acquire a body of information on the properties and potential applications of magnetic fluids, to study the selective coating behavior of magnetic fluids when contacted with a mixture of organic an inorganic matter, and to determine the extent of coal beneficiation that can be acccomplished with fluid-enhanced magnetic separation. Objectives were achieved by performing an extensive literature survey and by acquiring and testing samples of three fluids and several commercially-important domestic coals. Coal beneficiation tests were conducted in a high intensity induced-roll dry magnetic separator and in a high-gradient matrix-type wet magnetic separator. The induced-roll device could not beneficiate untreated coal, but high yields of magnetic clean coal were obtained when the feed was first pretreated with magnetic fluid. The high-gradient separator did achieve substantial coal beneficiation of untreated coal, and level of coal cleaning increased moderately when the feed was pretreated with magnetic fluids. However, yield of the nonmagnetic clean coal decreased. All magnetic fluids tested exhibited the ability to wet both organic and inorganic surfaces but showed a preference for organic surfaces. Testing of a high-ash preparation-plant refuse indicated that the organic fluid was capable of selective attachment to the organic components of a complex feed mixture. (ERA citation 05:037582)