Process Mineralogy Study on a Skarn Type High Argillaceous Refractory Tungsten-Molybdenum Ore Deposit in Henan

This is a paper in the field of process mineralogy. A silica-type tungsten and molybdenum mine in Shaanxi has diverse ore types and large variations in tungsten and molybdenum grades, and it is difficult to improve the concentrate grade and recovery. Multiple technics including microscopic observation, X-ray diffraction (XRD), scanning electron microscope energy dispersive spectrometer(SEM-EDS) and mineral liberation analyser (MLA) were adopted to study the mineral compositions, dissemination characteristics of target minerals and the distributions of valuable elements of the ore, and the beneficiation process scheme was explored and optimized. The results show that the valuable elements are tungsten and molybdenum, and the main target minerals are scheelite and molybdenite. The content of clay minerals such as soapstone and montmorillonite is high, which are the main harmful minerals affecting the flotation recovery of tungsten and molybdenum. Scheelite is mainly coarse- to medium-grained, and molybdenite is medium- to fine-grained. The proportion of -0.02 mm refractory particle size of molybdenite is up to 31%, which requires fine grinding to be liberated. The theoretical grade of molybdenum and tungsten concentrate by flotation of molybdenite and scheelite is expected to be 58% and 67%, and the theoretical recovery is about 76% and 92%, respectively. By adjusting the reagent system, the dispersion and inhibition of clay minerals such as saponite and montmorillonite, which are easy to float and slime, was strengthened in the beneficiation process, reducing the influence on the recovery of tungsten and molybdenum.