Selective Coalescence of Ultrafine Coal

摘要

The objective of the in-house work is to evaluate and define the beneficiation potential of selective coalescence techniques, and to accelerate their development as viable technologies for cleaning ultrafine coal to low ash levels. This work consists of three interrelated tasks: (1) development of in-house procedures, (2) verification and comparison of new selective coalescence technologies, and (3) advancement of the state-of-the-art. The first effort involves the establishment of standard laboratory test procedures through experimentation to assess the effects of operating parameters - such as conditioning and mixing time, feed solids weight, slurry concentration, and agglomerate recovery methods - on product quality and quantity. The second effort involves a comparison of the various selective coalescence techniques that have been or are presently being developed by various organizations including Otisca, TVA, Dow, Battelle, and the National Research Council of Canada. This work will be carried out both in-house and through direct participation by those organizations which are developing selective coalescence processes. The third effort will utilize information derived from the first two tasks. Tests will be done to examine the effects of coal such as size, rank, and surface characteristics; the properties of agglomerants such as adsorption selectivity, recoverability, chemistry, and miscibility; and the effects of operating conditions such as mixing and agitation, sample conditioning, ultrasonic treatment, and phase separation. Ancillary to this work we found it helpful to establish an in-house coal sample reserve to provide our various projects with well-characterized standard coal samples. Samples for this reserve will be stored under an argon atmosphere to minimize the effects of oxidation. (ERA citation 10:036028)