Scientists: Talk of phosphorite mining is premature
Before addressing the prospect of phosphorite mining in Estonia, scientists say additional research must be conducted so that phosphorite can be mined with other rare earth elements.
On the basis of the current evidence, scientists are convinced it is too early to determine the viability and necessity of phosphorite mining.
Estonia is known for holding some of the largest phosphorite reserves in Europe. Tiit Kaasik, head of the department for geological resources at the Geological Survey of Estonia, estimated that Estonia's deposits contain 2.9 billion tons of phosphorite, in addition to the country's lesser-explored phosphorite reserves.
"In total, Estonia holds approximately 11,3 billion tons of phosphorite, which is dispersed over a larger area, so the overall reserves are greater, but the exact numbers are not known; not all phosphorite sites in Estonia have been thoroughly studied," Kaasik said. The reserves, for example, in eastern Estonia are quite close to the surface and easier to study.
Phosphorite is interesting primarily due to its phosphorus content that is used to produce fertilizers. However, phosphorite also contains a significant quantities of rare-earth elements, such as cerium, praseodymium, neodymium, dysprosium and terbium, which makes phosphorite a potential raw material for rare-earth elements.
Veiko Karu, head of the mining department at the institute of geology at the Tallinn University of Technology (TalTech), said that "in addition to this phosphorus, there are also industrially useful rare earth elements that can be retrieved from phosphorite through further enrichment processes."
Rare-earth elements are essential components in the production of semiconductors, liquid-crystal displays (LCDs), and LED lamps, as well as in energy management, including the production of wind turbines and electric vehicles.
The application of extraction technologies in Estonia should pose no technological challenges, given that they have been developed and are widely used around the world. The only challenge is how to apply them in the context of phosphorus in Estonia.
Before suggesting whether and how much phosphorite could be mined in Estonia, both Karu and Kaasik said that the subject of phosphorite ore processing must be analyzed.
Researchers at the Tallinn University of Technology, geologists, and scientists at the Geological Survey are studying what technologies could be used to process this material in an environmentally friendly way in order to obtain phosphorus and rare earth elements, Karu explained.
Kaasik said that the Geological Survey has also launched the next phase of exploration, which will concentrate on phosphorite processing and refining.
"And, as Karu said, one of the most important questions is how to exploit this resource in an holistic way," Kaasik said.
"Our purpose is to extract as much value as possible from this ore by extracting not just phosphorus but also rare earth elements, as phosphorite also contains these elements."
The benefication of mineral resources is the process of improving the value of the ore without changing its chemical composition. For example, in the case of phosphorite, phosphorus-rich shells are separated from sand but also from other useful components such as rare-earth elements.
In light of worldwide developments in valorisation technology, the Geological Survey of Estonia, together with universities, is seeking the best possible solutions for phosphorite ore in Estonia.
Follow ERR News on Facebook and Twitter and never miss an update!
Editor: Mari Peegel, Kristina Kersa