Processing of Dolomites for Refractory Applications

摘要

This report presents specific research pertinent to various aspects of dolomite processing. The concept of reactive phase calsintering evolved from research on raw material effects. This process allows for the densification of dolomite in a single-step process in which the dolomite is first mixed with an oxide that will form a liquid at elevated temperatures and a compact formed by processing. The compact is then heated in a controlled manner to 1,100 C to effect the decomposition of the dolomite. The decomposed material is rapidly heated from 1,100C to the sintering temperature, where the liquid phase forms. The calsintering process is then extended to the sintering of calcium carbonate. The result of adding a chloride salt was investigated and determined to be deleterious to the calsintering of dolomite. It is believed that this is primarily an effect of the chloride salt on the decomposition product. To more fully understand this process, both chloride and fluoride salts were systematically added to dolomite, calcite, and magnesite and their effects on the decomposition was studied.