Evaluation of Estonian phosphate rock by flotation

•Estonia holds the largest unused sedimentary phosphate rock reserves, about 700 million tonnes P2O5 in European Union.•Estonian phosphate rock is particularly outstanding by its remarkably low content of hazardous heavy metals such as Cd and saturated by valuable elements present in the rock such as rear earth elements.•Considering at least 30 years gap, research in this field needs to recommence to evaluate the economic, technological, and environmental challenges for processing Estonian phosphorite.•Estonian phosphate rock can be beneficiated to produce high-quality concentrates at high recovery levels by modifying the main flotation parameters depending on the properties of the ore. Estonia holds the largest unexploited sedimentary phosphate rock reserves in the EU. Compared to other sedimentary and also igneous phosphate rocks the Estonian phosphorite is particularly outstanding by its remarkably low Cd(1–5 ppm) and trace U content (~50 ppm) and also contains valuable elements such as rare earth elements (REEs), which could be used in important high-technologies in the future. In this paper beneficiation by reverse flotation of the silicates for three types of Estonian phosphorite ores was investigated. The apatite concentrates with grades of over 33 wt% P2O5 at recoveries of 84.8 to 89.2% were achieved. The concentrates had low MgO contents and grades of FeO ranged from 1.29 up to 2.54 wt%. The study gives an overview of the specifics of enrichment of Estonian shelly phosphorite ores, provides a ground for future in-depth and pilot-scale experiments to find proper solutions for the Estonian phosphorite processing and will be applied in the feasibility studies of the phosphorite industrialization.