Gold in ash and slag material of the Primorsk hydroelectric power

Abstract

The paper shows the results of studies on the identification of noble-metal mineralization in various components of ash and slag formations: underburning, aluminosilicate microspheres, initial ash (fed to the magnetic separation of the technological section of Primorsk SDPP), magnetic and non-magnetic fractions – using analytical and mineralogical methods, electronic microscopy. An integrated approach made it possible to reliably establish significant concentrations of gold, to identify the factors of technological persistence of anthropogenic materials. All products contain free gold grains ranging in size from 50 to 230 micrometers and microscopic inclusions of 0.5-20 microns. The content of free grains of gold is from 0.4 to 1.37 mg / kg. The gold is pure or with an admixture of silver (up to 17% of the mass). Depending on the research materials, gold contains variable inclusions of magnetite, ilmenite, quartz, glass, amphiboles, pyroxenes, clay minerals, and carbonaceous formations. Gold grains have complex structure and morphology. Micronized inclusions, usually rounded, also contain an admixture of silver.