Project TI-RRES

Management information

Title: Evaluation of the potential of recovery o rare earths (REE) and other raw materials (Nb, Ta, Sn) from mining wastes of the Golpejas mine and its ecological restoration (TI-RRES)

Code: TED2021-130109A-I00

Initial date: 1 de December de 2022

Ending date: 30 de November de 2024

Funding: 101200 €

E-mail: t.llorens@igme.es

Project description

Comprehensive evaluation of the mining waste accumulated in the ponds and tailing dumps of the Sn-Ta Golpejas mine.

The TI-RRES project aims to carry out a comprehensive study of the mining waste accumulated in the ponds and tailing dumps of the Sn-Ta Golpejas mine, in Salamanca, in order to evaluate its potential for the recovery of rare earths and other critical raw materials, such as tantalum and niobium, and determine the possibilities of using industrial minerals, thus generating an economic, environmental and social benefit in the area, by favoring the return of land affected by mining waste facilities to a state suitable for the establishment of a self-sustainable ecosystem over time. This project is a clear example of Circular Economy and Ecological Restoration, both pillars of the ecological transition demanded by the EU and society in general, which allows the reincorporation into the production process of materials containing waste for the production of new products or secondary raw materials.

Targets

The dependence of the European Union on certain raw materials highlights a pressing need to move towards an economy with more efficient use of resources and sustainable development, thus it is necessary to ensure the supply of raw materials in quantity and quality suitable for the European industry.

With the development of the proposed study, the potential of abandoned mining waste to provide critical raw materials to the EU will be revealed, especially with regard to the supply of REE, which the EU currently lacks completely, making its study and valuation extensible to other deposits of secondary raw materials in Spain, which is currently one of the countries with the largest amount of this type of wastes. At the European level, it will contribute to guaranteeing the security of supply of these raw materials, reducing dependence on imports and avoiding the use of primary natural resources. This fact will favor the development of sustainable mining within the framework of the circular economy, reducing the energy and economic cost and minimizing the environmental impact of future mining operations. All these factors constitute basic pillars of the field of ecological transition.

Activities

Activity 1

Delimitation and evaluation of the volume of resources

Conducting field work to define the surface occupied by the different ponds and waste dumps.

Review of old aerial photographs to know the surface and depth extension, as well as the morphology of the old exploitation pits that are currently filled with the mining wastes. Development of geophysical studies using electromagnetic techniques (SEDT) that provide a clear profile and morphology of the reservoirs.

With all this, a calculation of the volume of accumulated mineral resources will be carried out.

Activity 2

Chemical, mineralogical and granulometric evaluation of resources

Systematic representative sampling of mining waste by performing pitches and taking surface samples. A preliminary geochemical control is carried out in situ by taking data with portable X-ray fluorescence equipment.

Chemical characterization of sand samples and fractions from different pitches, study using estereoscopic and optical microscopy, X-ray diffraction, scanning electron microscopy and electron microprobe.

Mineral liberation studies on samples of mineral concentrates of Sn, Ta, Nb and REE.

Comparison and integration of geochemical, textural and mineralogical results with information from the primary deposit.

Activity 3

Modeling and evaluation of resources

The geochemical, mineralogical and granulometric information will be integrated together with the information on the volume estimation in the different reservoirs, in order to model the resources of Sn, Ta, Nb and REE. To do this, there will be statistical support, the application of geographic information systems and the construction of 3D models.

Activity 4

Study of the best processing techniques

Study and evaluation of the best available techniques for the comprehensive use of mining waste, in a sustainable way and in accordance with the ecological transition objectives. Processing techniques based on gravimetric, magnetic separation and electrostatic separation, flotation as well as hydrometallurgical techniques, will be used. Additionally, the possibility of benefiting the minerals present in the tailings as potential raw materials for other value chains will be studied.

Activity 5

Ecological restoration

Mineralogical, granulometric and soil characterization of current mining waste. The results obtained from each sample will be combined with the appearance of the sample taken in the field, the degree of vegetation cover and its composition, and the recognition of edaphic structure, as well as the rest of the analytical results of geochemical and mineralogical characterization. The mining wastes resulting from the metallurgical and hydrometallurgical tests developed will also be studied, in order to define its limitations in order to sustain ecosystems, thus anticipating what will happen in the future it they are produced massively and restoration is needed.