Melhorar a circularidade do tratamento de águas residuais: Concepção de uma nova solução

The overall objective of the proposal is to develop an innovative and easy-to-apply solution to treat wastewater for reuse, facing the emerging compounds pollution, and be available to the water sector. Ultimately, the solution will contribute to the zero-pollution ambition regarding wastewaters discharge and to the circularity in the water sector, by involving the water actors. It includes, not only treating wastewater to safe levels but also eliminating pollution and transforming pollutants in value-added products. Thus, the proposal will cover the following specific objectives: O1: Design and develop a recyclable filter medium capable of removing micropollutants from wastewater: The project proposes to develop a nanocomposite filter medium made from an adsorbing material, such as reduced graphene oxide (rGO), where metal/metal oxide nanoparticles (NP) will be incorporated to act as catalysts in its recovery process. This filter medium is expected to be able to remove both traditional and emerging contaminants from wastewater, producing decontaminated water safe for reuse in several applications. O2: Develop methods to valorise the pollutants adsorbed and removed, regenerating the filter medium for reuse: For process circularity, recyclability of the filter medium must be guaranteed and pollutants eliminated, so the project also intends to develop simple methods for this. Two different approaches will be evaluated, one based on chemical methods and another based on biological methods. The idea of the former is to try to transform pollutants, through thermal treatment or photocatalysis, in water and CO2 and capture it in the form of carbonates or use it to grow biomass, for example. Alternatively, pollutants may be used as raw material for the production of carbon-based materials, such as graphene or graphene oxide, which are potential candidates as filter mediums. The latter approach intends to use microorganisms to degrade the pollutants either to CO2 and water or to metabolites which will be treated as described above. O3: Engage the stakeholders in the solution design and testing: Stakeholders from aquacultures, water companies, agri-food companies, etc. will be involved in the project through workshops and multi-criteria decision analysis incorporating their information, technical skills and expertise to support the development of the solution, select the best one and study it at a pilot scale. O4: Test the best solution at pilot scale: The best filter solution is planned to be tested at pilot scale in different wastewater scenarios corresponding to the wastewater produced in stakeholders' companies/industries. O5: Assess the environmental risk of the solution proposed: The proposed solution poses the potential risk of leaking the filter medium. This is of particular concern since nanomaterials are involved (rGO, NP). Thus, the potential environmental risk of the nanocomposite filter medium will be evaluated to guarantee the safety of the treated wastewater. The project emphasis on wastewater reuse aligns with a forward-thinking and sustainable perspective. Globally, water scarcity is a growing concern so recycling treated wastewater for various applications can contribute significantly to mitigating this issue. The integration of novel and advanced materials and the required interdisciplinary reflect a forward-looking approach to address the challenges of wastewater treatment, marking a potential breakthrough in the field.