De Resíduo a Recurso: Bioprocessos para reciclagem de rejeitados da indústria mineira em alinhamento com a lei de matérias-primas críticas

The W2R project introduces an innovative and sustainable approach to resource management by harnessing tailings as a source of metals and raw materials for construction. The primary goal is to shift the perception of tailings from mere waste to valuable secondary resources for extracting metals of economically relevant metal(oid)s (As, Al, Ni and Mn) and products with high value essential (technosols; construction materials). This involves exploring the diverse potential of tailings as raw materials, aiming to reduce dependence on primary sources and minimize the environmental impact associated with traditional extraction methods. By employing bio-based technologies, the project seeks to efficiently recover residual metals from tailings, ensuring a more environmentally friendly utilization of mining by-products. Recycling these residues, repurposing them for specific applications, enhances the versatility and adaptability of tailings-derived resources. This approach aligns with the principles of the circular economy, aiming to mitigate the environmental impact of tailings piles and promote a sustainable resource utilization model. The objective of the project extends beyond resource recovery; it addresses environmental concerns by contributing to the rehabilitation of mining sites and reducing the ecological footprint of the mining industry. Ultimately, this effort aims to foster public acceptance of mining activities by showcasing their potential positive impact on the environment through responsible and innovative practices. Therefore, the objectives of the project can be divided into several topics: i)Technical: 1) high mobilization of important metals; 2) eco-friendly approaches with high selectivity and efficiency; 3) new native or engineered cells able to produce organic acids (oxalate and citrate) and accumulate target metals (Ni and Mn); 4) validation of the whole process for sustainable reuse of the mine residues. ii)Economic: 1) exploitation of a huge fraction of rejected materials, which will allow reducing the dependency of the EU from critical metals importations; 2) a low-cost process, minimizing the use of materials and energy consumption, ensured by LCC; 3) development of circular economy model to put on the market products with high value (e.g. tecnhosols). iii)Environmental: 1) valorisation of waste reducing the amount and hazard of mine waste disposals; 2) development of more eco-friendly processes than the conventional methodologies. iv)Social: 1) improve the awareness of society regarding the importance of metals from secondary sources; 2) foster public acceptance of mining activities 3) knowledge dissemination through scientific publications, specialised congresses, workshops and genetic sequences deposited in public databases.