A real-scale application experience Natural Treatment Systems for Wastewater $\left(NTSW\right)$ operating in continues with livestock farms for one year. These systems are based on digesters, subsurface vertical flow constructed wetlands $\left(SVFCW\right)$ and facultative ponds. Chemical Oxygen Demand removal efficiency $\left({COD}_{RE}\right)$ has obtained between 70 and 90%. Likewise, it have been possible to compare the operation of cascade flow digesters $\left(CFD\right)$ (<76% ${COD}_{RE}$) versus complete mixing digesters (CMD) (<50% ${COD}_{RE}$). Facultative ponds $\left(FP\right)$ when combined with $\left(SSFCW\right)$, removed a higher percentage of ${COD}_{RE}$ compared with ponds (92%). Correlations of interest have been found between the variables evaluated in each plant. Finally, different elements are alternated in the same system, this system is capable of supporting variations in changes in flow rate and organic load coming from the farm, maintaining an adequate elimination of $COD$ and other parameters of interest.

The objective of the described activity is to develop technologies or proposals that can be implemented within the cycle to enhance the relationship between climate change, water, energy, and food. The focus is on analyzing natural treatment systems for wastewater (NTSW) within the context of Macaronesia, considering factors such as life-cycle assessment (LCA), carbon footprint, impacts, and mitigation capacity. The analysis of real case data from the Canary Islands and Cape Verde will inform the development of appropriate technologies tailored to different areas and scales within Macaronesia. This work includes a comprehensive life-cycle analysis of the Santa Catarina (Cape Verde) NTSW. This analysis encompasses: (a) Inventory analysis of the construction phase: This involves the assessment of inputs and outputs associated with the construction of the NTSW, including materials, energy consumption, transportation, and waste generation. The maintenance and operation phases are then evaluated, with a focus on the ongoing maintenance and operation activities required for the NTSW, including energy consumption, water usage, chemical inputs (if any), labor, and equipment maintenance. (b) Finally, the impacts of the NTSW are evaluated. The environmental, social, and economic impacts generated by the NTSW are assessed. This includes an analysis of factors such as carbon emissions, water usage, land use, ecosystem impacts, human health effects, and economic costs. By conducting a comprehensive analysis of the Santa Catarina NTSW, the document aims to provide insights into the environmental performance and sustainability of the system. This information can then be used as a tool and experience of educational innovation for final-year undergraduate students to identify areas for improvement, develop mitigation strategies in the water sector, and inform decision-making processes regarding wastewater treatment technologies in Macaronesia. Furthermore, lessons learned from real case studies in the Canary Islands and Cape Verde can be applied to similar regions within the Macaronesia archipelago (IDIWATER project).

This work presents an original 3D code in FreeFem++ to recreate the behavior of anaerobic microorganisms in non-stirred anaerobic reactors with an intermittent feed. The physical and biochemical phenomena have been considered using a mathematical model based on a set of partial differential equations: Stokes, advection–diffusion, and diffusion–reaction. The description of the anaerobic metabolism was carried out by implementing the structured AMD1 model. The Galerkin finite element method has been used to solve the partial differential equations defined in the model. Finally, the methodology and procedures are presented by means of a concrete example. Thanks to the inclusion of this e-learning tool for use in virtual laboratories, it is possible to improve the understanding of engineering students on the functioning of the metabolism that takes place inside non-stirred anaerobic reactors that are fed discontinuously. This proposal reinforces to students, in a transversal way, both environmental sensitivity and awareness of the circular economy focused on the implementation of natural wastewater treatment systems in rural areas.

This work proposes a series of strategies and tools for the design and characterization of natural treatment systems of wastewater (NTSW) applied in livestock farms, considering the parameters of flow rate (Q), conductivity (EC) and chemical oxygen demand (COD) of the waste generated, farm location, hydraulic retention time (HRT), and removal/reduction rate targets. The high organic load of the effluent generated in these farms has an important environmental impact, which is amplified in insular or isolated territories. The application of such treatment systems has demonstrated their suitability in these environments, but their design lacks proper characterization and sizing tools for their adequate operation. The proposed tools in this work are based on a collection of experimental data over a ten-year period of application of NTSW in real farms. This work contributes to facilitate the design and implementation of NTSW in farms located in isolated, island, or similar-size environments. Finally, as a practical application, an inventory and implementation of the tool developed for livestock farms on the island of Gran Canaria (Spain) is carried out.

The objective of the described activity is to develop technologies or proposals that can be implemented within the cycle to enhance the relationship between climate change, water, energy, and food. The focus is on analyzing natural treatment systems for wastewater (NTSW) within the context of Macaronesia, considering factors such as life cycle assessment (LCA), carbon footprint, impacts, and mitigation capacity. The analysis of real case data from the Canary Islands and Cape Verde will inform the development of appropriate technologies tailored to different areas and scales within Macaronesia. This work includes a comprehensive life cycle analysis of the Santa Catarina (Cape Verde) NTSW. This analysis encompasses: a) Inventory analysis of the construction phase: This involves the assessment of inputs and outputs associated with the construction of the NTSW, including materials, energy consumption, transportation, and waste generation. The maintenance and operation phase is then evaluated, with a focus on the ongoing maintenance and operation activities required for the NTSW, including energy consumption, water usage, chemical inputs (if any), labour, and equipment maintenance. Finally, the impacts of the NTSW are evaluated. The environmental, social, and economic impacts generated by the NTSW are assessed. This includes an analysis of factors such as carbon emissions, water usage, land use, ecosystem impacts, human health effects, and economic costs. By conducting a comprehensive analysis of the Santa Catarina NTSW, the document aims to provide insights into the environmental performance and sustainability of the system. This information can then be used to identify areas for improvement, develop mitigation strategies, and inform decision-making processes regarding wastewater treatment technologies in Macaronesia. Furthermore, lessons learned from real case studies in the Canary Islands and Cape Verde can be applied to similar regions within the Macaronesia archipelago.