Feasibility study of high-pressure grinding rolls in tungsten ore comminution: comparison on the products characteristics and gravity separation performance of two crushing methods

Tungsten ores exhibit high brittleness and a tendency to sliming, which significantly limits the application of high-pressure grinding rolls (HPGRs) in tungsten ore processing. To explore the feasibility of applying HPGRs, this study conducted a comparative experiment between HPGRs and jaw crushers for tungsten ore comminution. The experiment employed the tungsten ore from a mine in Jiangxi Province, China, which had been pre-sorted by sensor-based sorting. Particle size distribution and mineral liberation of the two crushed products were systematically characterized. Additionally, particle morphologies and surface roughness were examined using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Combining these observations with grinding kinetics, the influence of the two crushing methods on subsequent grinding processing was deeply evaluated. Particle-size-screened gravity separation tests were also performed. Results indicate that HPGRs accelerate the liberation of tungsten minerals. When combined with pre-screening before grinding, HPGRs significantly enhance rod mill grinding efficiency and mitigate the sliming phenomenon, resulting in a 3.22 percentage point increase in gravity separation recovery. The findings provide data and reference for the industrial application of HPGRs in tungsten ore processing.