METHOD OF PREPARATION OF QFSM OF VARIOUS GRADED COMPOSITION BY DRY-CLEANING PROCESS Russian patent published in 2009 - IPC B07B9/00 

FIELD: mining engineering.

SUBSTANCE: invention is in the field of development, particularly in pegmatitic development. The area of application - dressing plants engaging in preparation of quartzo-feldspathic mixtures from decayed pegmatitic ores. The method of preparation of quartzo-feldspathic mixtures of various graded composition by means of dry-cleaning process comprises feed stock drying, preliminary treatment of quartzo-feldspathic feedstock by disintegration with subsequent classification in gravitational air classifier, dry magnetic separation for iron removal. The feedstock is disintegrated in two stages: at first it is disintegrated in the centrifugal percussion mill and then in the screen Kroosher with simultaneous classification by the following 5 grain-size classes: +1; -1+0.5; -0.5+0.25; -0.25+0.1; -0.1+0 mm. Then the material is transferred for magnetic separation performed in two stages with obtaining two magnetic and one nonmagnetic fraction of each grain-size class. Nonmagnetic fractions of the following grain-size classes +1; -1+0.5 are subjected to aftergrinding to - 0.5 mm grain size and then together with nonmagnetic fractions of -0.5+0.25; -0.25+0.1 grain size they are subjected to aftertreatment i.e. the second stage of magnetic separation. The material produced in gravitational air classifier is subject to the second stage of integration.

EFFECT: improved separation and iron removal efficiency as well as an increasing degree of technological characteristics contrast owing to precious material development.

2 dwg,1 tbl