Solar thermal treatment of manganese ores can potentially lower energy costs and reduce greenhouse gas emissions. The solar thermal treatment of three manganese ores resulted in thermal decomposition and reduction of the ores. Empirical results compared to thermodynamic equilibrium models and numerical heat transfer models informs the next steps towards proving the concept. The study provides information regarding the bulk thermal conductivity of manganese ores as determined by optimization of the heat transfer model parameters. Changes observed in the mass of the solar treated samples confirm thermal decomposition and reduction of manganese and iron minerals.

Understanding the behaviour of plasma arcs is an important part of the design and operation of direct current electric arc furnace smelting processes, which are used in the industrial production of many metallurgical commodities. In recent years numerical and computational modelling techniques have begun to illuminate the complexity of arc behaviour and how it is deeply connected to the thermodynamic and physical properties of the arc plasma. Plasma properties may be estimated from first principles using statistical mechanics methods, but this requires as input some knowledge of the composition of the gas phase that occurs over the process during smelting. In this paper the authors describe a workflow using thermochemistry software to predict the expected gas phase composition through a given process, followed by plasma property calculations using an open-source software tool that has been in development for several years. This tool, 'minplascalc' has been in development for several years and is also described in detail here. The workflow is then applied to the calculation of plasma properties of interest for a variety of historical and current pyrometallurgical processes, and the results are compared. The plasma property data are published in an open-access database for general use.