Microwave enhanced roasting for pyrite ore samples with dielectric properties strongly dependent on temperature

Abstract

<p>This article shows the main experimental results related to the measurement of dielectric properties of Pyrite ore mineral samples as a function of temperature, and their effect on the heating behavior of the samples. It was found that the sample’s dielectric properties strongly depend on temperature. The best model for and that fitted the experimental data, was a Gaussian model. Besides, and under certain conditions, it was possible to roast the mineral even better than with an electric furnace, while requiring less processing time and with lower electrical energy consumption. Additional exploratory tests revealed that microwaves can be used to smelt a roasted mineral ore with time reductions of about 90%, while keeping recovery margins above 95%. Thus, we conclude that, as a next stage, the process should be directed to using a single mode applicator, for processing higher volumes of mineral at pilot plant scale.</p>

Conventional versus microwave-assisted roasting of sulfidic tailings: Mineralogical transformation and metal leaching behavior

“…4), indicating that the sulfate-to-oxide phase transition of sphalerite (ZnS) also occurred at a faster pace during MR. Given that most sulfide minerals are good microwave absorbers [42], such fast and selective heating during MR is expected to give a similar effect to chalcopyrite (CuFeS2) and galena (PbS) as the respective main Cu and Pbbearing minerals in the tailings.…”