Flotation of Polish hard coal in saline water

Abstract

With the use of process water (saline), the ash content in the concentrate was 6% and in the tailings up to 70%. Of course the upgrading plants which apply flotation for coal slurries still use mine water in technological processes. The water quality, particularly the content and type of salts in water, fundamentally influences the surface properties of phases which remain in contact during the process, that is the solid, gaseous and liquid phases. The properties of these phases and interactions between them determine the probability of occurrence of elementary flotation actions (Brożek and Młynarczykowska, 2005, Brożek and Młynarczykowska, 2008): collision, adhesion and separation, and ultimately the upgrading process effectiveness expressed by technological parameters. The paper presents the results of flotation effectiveness analysis for coal as a model raw material. The object of evaluation was qualitative parameters of the upgrading process products on the basis of flotation tests conducted for variable pulp salinity. The principal goal was to determine the impact of process water quality on the course and effectiveness of flotation.