A Study Of Graphite Ultrafine Grinding

Graphite is a laminated structure mineral with the exceeding lubricant and tough properties. How to ultrafine grind graphite effectively is a difficult problem for a long time. This dissertation mainly involves in study of superfine grinding on graphite.In this study, the vertical spiral type stirred mill, a new equipment for superfine grinding with high efficiency, is adopted. The influence of the main operation parameters, such as pulp density, stirrer rotating speed, milling medium's kinds and size, grinding time and dispersants, on superfine grinding efficiency of stirred mill were studied systematically. The reason of the influence was also analyzed in detail.A good technology was established according to the results of experiment and the parameters are as follow: Φ5mm diameter steel ball, 25% concentration of slurry, the stirrer rotating speed of 250rpm, the optimum addition of dispersant(CMC)l%, slurry pH is regulated to 10+0.5. It was testified that superfine grinding is high-efficient. After ground 60 hours, graphite particles yield (<1μm) can be achieved to 72.07%, graphite particles yield (<2μm) can be achieved to 98.65%, the median particles (d₅0) can be achieved to 0.71μm. The flaky shape of graphite particles is well protected.Based on the test results, introducing dispersant is able to increase ultrafine grinding efficiency greatly. The performance of adding dispersant is somehow coincident with the rheology adjustment theory of slurry. Particularly, the viscosity of the slurry can be reduced dramatically by adding CMC. Accordingly, rheological property of the slurry can be improved. Therefore, ultrafine grinding efficiency is raised.