Metallurgy of Dictyonema
| Reference number | |
| Coordinator | ScandiVanadium Sweden AB |
| Funding from Vinnova | SEK 500 000 |
| Project duration | March 2020 - February 2021 |
| Status | Completed |
| Venture | The strategic innovation programme for Swedish mining and metal producing industry - SIP Swedish Mining Innovation |
| Call | Towards a sustainable development in the mining and metal extraction industry |
Purpose and goal
The aim of the pre-study was to test the application of POL (Pressure Oxygenation Leaching) for extracting vanadium from shale in Skåne. The extraction of V was lower than expected and chemical analyzes of the test results, together with a comparison of geological parameters, have resulted in the conclusion that further study is required to determine improved recovery. The project has shown that the approach with several complementary analytical methods has been successful for understanding the chemical reactions during the metallurgical tests.
Expected results and effects
The expected result was to gain a better understanding of the Dictyonema shale metallurgy and study the application of POL to yield vanadium from the material. The recovery rate was relatively low and thus did not live up to expectations. However, the analytical data together with the comparative study means that we understand what happened in the samples and to some extent why. The comparisons also show that it is probably possible to find extraction methods for this shale that may yield high recoveries.
Planned approach and implementation
Two series of experiments were performed under oxygen overpressure and with low pH. Temperature and time were varied and after each experiment the sample was divided and analyzed for surface and bulk chemistry and for mineral content and relative levels present in the sample (XRD), hence a measure of the mineralogical changes that have taken place. The approach worked excellently and is a successful way to analyze the mineralogical changes and thus understand the metallurgical process. Furthermore, a litterature study compared the Skåne site with relevant projects globally.