The net value added in the production of silicon metal depends on the quality and availability of its raw materials carbon and quartz. This logic is valid throughout the entire supply and value chain – including the silicon manufacturer, raw material traders, and the mining companies.
High-quality raw materials are rare
When searching for new raw material sources, obtaining an early reliable prediction of the raw materials quality is vital. After all, the operator ‘s primary goal is to mine good quality resources over many years. Prompted by the silicon manufacturers to deliver raw materials of demonstrable
quality, the trade fraction applies the same standards.
Raw material analysis: a cost factor or compromise solution?
SiO reactivity is the most common evaluation method to determine the quality of raw materials. This method allows for a rather essential, but not necessarily reliable indication of the expected silicon yield. Statements on silicon quality cannot be derived using this method. An accurate assessment of raw materials is only possible on an industrial scale covering a few hundred tons of raw material, which is complicated and expensive.
New precision in raw material testing
During the JPM Raw Material Test, an actual silicon sample is produced from the raw material sample in our microwave furnace. The thus drawn sample equals the melting result on the industrial standard of the SAF (submerged arc furnace).
Based on the obtained silicon sample analysis of the impurities values of iron, aluminum, calcium, and titanium are done by ICP-MS for a precise assessment of the expected silicon quality. XRD analysis determines the expected silicon yield of the tested raw materials. For this method, a few kilograms of the raw material are sufficient.
Case study: SiO reactivity is non-conclusive
The exclusive focus on the SiO reactivity leads to the assumption that the alternative coal would lead to similar results in production. Observation of the achievable silicon grades clarifies that the El Correjon produces a more economical result due to an obtainable increase in silicon quality. This economically relevant statement is made possible by the JPM Raw Material Test