부산대학교 도서관

For ores subject to magnetic separation, the magnetic properties of minerals and ores are the main determinants of the technological process of enrichment. Changes in the magnetic characteristics of minerals and ores during grinding affect the efficiency of flotation, magnetic and electrostatic separation, filtration and other technological processes. The study of these changes in the processes of mineral processing is relevant for the improvement of rational schemes and methods of processing and integrated use of mineral resources. The main trend of changes in the magnetic properties of magnetite quartzites, which we record during grinding and a corresponding reduction of the grain size of minerals, is a gradual decrease in specific saturation magnetization due to crystal chemical changes. We refer to such changes as qualitative, because they definitely affect the result of the technological process – obtaining a concentrate with the maximum possible iron content. At the stage of wet beneficiation, significant qualitative changes in the magnetic properties take place: 1) a gradual decrease in the magnetization of the source ore during grinding in ball mills with subsequent separation into magnetic concentrate and nonmagnetic tails;2) the gradual decrease in the magnetization of magnetite aggregates as a result of disruption of its domain structure and partial oxidation with the formation of new mineral phases – magemite and hematite / martite. Due to multi-stage magnetic separation, mineral neoplasms – magemite and hematite / martite, as a rule get into the enrichment waste, which provides the opportunity to obtain a high-quality concentrate with maximum iron content. Along with the changes in magnetization, we recorded a natural gradual decrease in the Curie temperature of industrial products in the process of enrichment of ferrous quartzites.