On January 1, 2023, our Laboratory officially started the implementation of the new research project entitled "Management and Utilization of Sewage Sludge in the Circular Economy using Green technologies and methods" with Assistant Professor Alexandros Stefanakis of the School of Chemical and Environmental Engineering as scientific coordinator.

The project is funded by the Green Fund of the Greek Ministry of Energy and Environment in Priority Axis 3 "RESEARCH AND IMPLEMENTATION", of the funding program "NATURAL ENVIRONMENT & INNOVATIVE ACTIONS 2022".

The coordinator of the project is our Laboratory, while the companies DEYACH (Municipal Water Supply and Sewerage Company of Chania) and DEDISA (Intermunicipal Solid Waste Management Company of Chania) also participate as partners.

The kick-off meeting of the project took place on 17/1/2023 at the Laboratory facilities with the participation of the key members of the partners:

- Asst. Professor Alexandros Stefanakis (scientific supervisor)

- Elissavet Koukouraki (Technical and Teaching Staff)

- Panagiotis Regouzas (phd candidate)

- Christina Tsamoutsoglou (DEDISA representative)

- Christina Kotsifaki (DEYACH representative)

The kick-off meeting purpose is to define the main priorities for the implementation of the project and the coordination between the partners for the implementation of the individual actions.

The project presents an innovative integrated model for the circular management of sewage sludge produced in sewage treatment plants. It implements and studies the green technology of Sludge Treatment Wetlands, which is based on natural processes and components minimizing greenhouse gas emissions and operating costs, in contrast to established mechanical technologies. The cycle of dewatered sludge is then closed with the study of reuse and application in agriculture. At the same time, as a second cycle, the co-composting of the reed plant biomass produced by the Sludge Treatment Wetlands is considered. The last cycle is the production of biochar from the same materials, as a biological adsorbent media useful in crops production. All materials and biosolids will be evaluated for their final quality and tested as soil conditioners in crops. Material cycles will be assessed in terms of their environmental footprint, their economic dimension (life cycle analysis and costing) and social acceptance.

These practices and methodological approach are also in line with the EU Circular Economy Action Plan (2018) which is part of the Green Deal, to better manage bio-waste and encourage the reuse and recovery of waste. The proposed model incorporates at its core the need to reduce the environmental footprint and greenhouse gas emissions in an important industrial sector such as waste management. This is achieved by researching and developing an innovative green eco-engineering technology for sludge treatment, which is expected to reduce the overall environmental footprint and greenhouse gas emissions by more than 90% compared to the current linear management model. This is due to the very small need for energy, which can be covered by renewable sources, the elimination of the need for frequent transport, the elimination of the use of chemicals, and the use of only natural materials and processes. This practice is in line with Greece's commitment to significantly reduce greenhouse gas emissions in the context of the European plan "Strengthening Europe's climate ambition for 2030" and the strategy outlined by the Green Deal to decarbonize the economy, as well as with the National Strategy for Adaptation to Climate Change (April 2016).

In addition, the project develops new materials through further methods for the utilization and exploitation of nutrients in agriculture and other beneficial applications. The utilization of a material rich in nutrients is also imposed by the need to mitigate the effects of climate change, such as soil degradation and desertification, phenomena that are observed in Greece and especially in Crete. The use of these materials in the cultivated soil contributes to the preservation and restoration of the ecosystem, allows the sequestration of carbon from the atmosphere, reduces pollution from the use of chemicals and fertilizers, and improves the health of the soil and the crops produced, goals set by the European Green Deal and the 2030 Biodiversity Strategy. Therefore, the proposed project is fully aligned with national and European priorities and policies against the background of the goal of a climate neutral Europe by 2050.