Mineralogy and Characterization of Phosphate Rock for Direct Application

摘要

Phosphate rock (PR) is the major raw material component used to produce practically all phosphate fertilizers. The primary phosphate compound in PRs of commercial interest is some form of the min-eral apatite. Depending on the origin of the PR and itsgeologic history, the apatite may have widely differing chemical and crystallographic characteristics and physical properties. Distinctive suites of assessory minerals are also associated with PRs of various origins and geologic histories. The mineral-ogical, chemical, and textural characteristics of phosphate ores and concentrates determine their suit-ability for various types of beneficiation processes to upgrade the ores and remove impurities, adaptability for chemical processing by various routes,and suitability for use as direct-application fertilizers. The factors that are most important in the assessment for direct application are grade, suitability for eneficiation, and the reactivity of the apatite.