Mineral Processing Plant High Purity Graphite Using Comminution Pressure Leaching And Flotation

Among the phyllosilicate family, mica has many industrial applications thanks to its sheet crystallographic structure giving rise to unique physicochemical, electric, mechanical, thermal and mineralogical properties . Its application fields include capacitors, plastic fillers, insulators, pigments and aeronautical industry . Previous studies were performed in order to produce 3D components for various applications using ceramic materials by the inkjet process . Many applications include fuel cells or other electronic components . Given the electrical and thermal properties of mica, it seems a promising candidate for inkjet printing of 2D or 3D components. However, the powder must be of a size compatible with the diameter of the printing nozzles, in order not to obstruct them. Nozzle suppliers recommend using powders for which 90% by volume of the particles (D90) have a diameter fifty times smaller than the opening diameter of the printing nozzles . The opening diameter of the nozzles used in our case is 52 μm, which imposes a D90 lower than 1 μm. Generally, micas in their natural state are not as fine (several hundreds of micrometers), so grinding is necessary. Mica grinding is considered as an industrial challenge because of its laminar structure and mechanical properties. Its hardness ranges between 2.8 and 3.2 according to the Mohs scale. A combination of impact, friction and delamination is necessary for size reduction. Moreover, the finer the particles, the more friction is necessary, often associated with longer grinding times (10 h for grinding by sonication in ). 

Hengyang Company is one of company in China that offers a one stop shopping concept for graphite projects covering the whole value chain from drill core analyses up to process development for obtaining saleable graphite products, sample production and engineering of a processing plant. The main stages of the process may be summarized as:

– Pre-processing

– Physical processing

– Chemical and thermal processing

– Refinement