A1. Characterization of wastewater

Characterization of the primary effluents in the selected WWTPs was performed.

A2. Definition of System Requirements

Specific requirements for FO-RO, AnMBR and monitoring system were defined.

B1. Design of pilot plant

From the results obtained in the Preparatory Actions, and given the specific characteristics of the wastewaters to be treated by the pilot, the design and detailed engineering was completed.

B2. Design of the monitoring system and LIFE GREEN SEWER software development

The system of sensors and the associated software were designed, according to the results obtained in the Preparatory Actions and the pilot design developed in parallel in B1.

B3. Construction and integration of pilot

Construction and installation of the pilot system, according to the results obtained in B1 and B2 was finished.

B4. Validation of the pilot plant

The validation of the LIFE GREEN SEWER pilot plant was conducted at two demo sites over different operational periods. In Ferrol, the system operated for 11 months. The FO-RO process successfully concentrated organic matter and achieved the objective of 70% reduction of 90% of the detected emerging contaminants. At both sites, the FO-RO process produced regenerated water that meets Quality 2.1 standards in accordance with Spanish RD 1620/2007 and qualifies as class B under the newly applied Regulation (EU) 2020/741.

The AnMBR demonstrated strong performance in suspended solids retention, maintaining minimal turbidity for most of the operational period. COD removal was notable, and the ultrafiltration membranes effectively removed a great amount of emerging pollutants.

Low biogas production was attributed to the low load of inlet wastewater, and this production went largely undetected, likely due to dissolved methane or flowmeter errors caused by low biogas flow rates.

B5. Replicability and transferability

To ensure transferability and replicability, specific guidelines were developed for different characteristics of influences, locations, climates and socio-economic environments:

• Analysis of the market for the new system and its envisaged products and described actions for the project’s afterlife, such as trials in a third demo site and planning for full-scale development of the secondary treatment technology.
• Business Strategy Plan based on the development of the project’s results.
• Provided guidelines for implementing LIFE GREEN SEWER in other geographical areas and treatment plants, addressing different types of wastewaters and including seven scenarios.
• Conclusions from different visits to both demo sites, further ensuring the effectiveness of this action.

B6. Study of the commercialisation of the streams

Once assessed the market for the products originated in LIFE GREEN SEWER, the main takeaways regarding commercialisation are summarised below:

1. Water scarcity, population growing, strict legal documents for wastewater and chemical contamination are driving the growth of the market of water and wastewater technologies worldwide, which represents replicability opportunities for the GREEN SEWER system.
2. Replicability will be boosted by focusing on the provision of regenerated water for agriculture. This sector has historically accepted this resource.
3. The market for biogas plants is increasing, and hence, market opportunities exist for progressively replacing feedstock by them used, advancing towards the consumption of sewage, by means of the use of systems like GREEN SEWER. Plus, initiatives like the Biogas Roadmap (available in Spain), will boost penetration of biogas in substitution of other energy sources.
4. In order to allow marketability of the nutrient-rich by-product, and having reviewed the law of application, two options may be studied:
   • The selection of a targeted type of fertilising product and the implementation of efforts in order to achieve the requirements for that product, as per the values described in the law.
   • The formal request for the inclusion of new substances into the Regulation (EU) 2019/1009.

1. Contacts should be established with producers of fertilisers in order to start processes for signature of agreements, facilitating market uptake of the by-products produced in GREEN SEWER, hence facilitating replicability and transferability of the results.

C1. Monitoring of specific indicators of project’s progress

To evaluate the project’s impact, a set of Key Performance Indicators (KPIs) was established on the webtool of LIFE program, based on the initial KPIs identified in the proposal. For each KPI, both a baseline value and a target value were set, with targets to be achieved by the end of the project and three years thereafter.

C2. Monitoring of the project’s impact on the environment

The Life Cycle Assessment (LCA) of the LIFE GREEN SEWER system revealed that the technologies developed in the pilot plant have a significantly lower environmental impact than conventional ones and are beneficial for water reuse and nutrient and biogas recovery, especially in water-scarce environments.

C3. Socio-economic Impact

Economic assessment of the LIFE GREEN SEWER technology revealed that while the pilot plant’s initial costs was high compared to conventional methods, scaling up significantly improves cost-efficiency.

Moreover, social impact evaluations showed that infrastructure and power consumption are key areas affecting the technology’s overall impact, with performance improvements, particularly in power consumption, being crucial. The technology demonstrates competitive potential against traditional and advanced wastewater treatments when scaled and optimized for performance.

D1. Dissemination Planning and Development of the Dissemination Pack

Five newsletters have been published in LIFE GREEN SEWER presenting the project, disseminating the first results obtained and following up on the subject.

• Newsletter August 2022: Presentation of consortium and first steps of the project.
• Newsletter February 2023: Objectives, first results and project follow-up.
• Newsletter June 2023: Business plan and commercialization.
• Newsletter January 2024: Interview with Socamex, partner of LIFE GREEN SEWER, on the occasion of the installation of the project’s pilot plant at the wastewater treatment plant they manage in Almendralejo.
• Newsletter February 2024: Final event of the project. Main results obtained and conclusions.
• Layman’s Report: Main activities, results and conclusions of the research carried out in the project.

In addition, in order to obtain objective data on how LIFE GREEN SEWER could impact society, we created and sent a survey to professionals in the sector.

CETIM, leader of the project, sent a press release for the World Water Day to spread the word about LIFE GREEN SEWER. Several Galician media echoed the research carried out in the project, for example La Voz de Galicia.

Other specialised media, such as Revista Alimentaria, have continued to disseminate the good results obtained in the research.

D2. Networking with Other Projects, Project’s Seminars & Workshops & Other Activities for Project’s Outputs Diffusion

GREEN SEWER has participated in the following events:

• LIFE17 Kick-off MEETING. It was held on Brussels on November 6 and 7, 2018.
• SmartCity Expo World Congress is the world’s biggest and most influential event for cities and urban innovation. It was held in Barcelona between November 13 and 15, 2018.
• VII Jornada sobre BioReactores de Membrana It was carried in Barcelona on the 16^th may The event aimed to offer a framework for the discussion with different experts about the development of Membrane Bioreactors systems as well as other treatment processes in general.
• EIP Water Conference This event was held in Zaragoza between December 11^th and 13^th, 2019. The general objective of the event was to raise awareness about the need and urgency to improve water management throughout the European Union towards a water-smart society, as well as promoting the exchange of best practices and innovative approaches at the technical, government and policy levels.
• LIFE WASTE-WATER TREATMENT PLATFORM MEETING. It was organised by CETAQUA on 29 January 2020 in Barcelona for formulate policy on several areas of significant importance, as for example, circular economy of water and sludge, pollutants of emerging concern, urban runoff and stormwater overflows.
• FINAL EVENT of LIFE DRAIN RAIN Project in Ferrol on October 2022, during this event, a summary of the activities carried out and the results obtained of the LIFE GREEN SEWER was presented.
• FINAL EVENT of Project Ô collaborative workshop with SOCAMEX held in January in Almendralejo (24/01/2023). The main objective of the Project Ô was to implement a circular economy approach while supporting the detection and processing of complex pollutants and the protection of water treatment plants and water reuse using the MOBILE3TECG technology in the EDAR of Almendralejo.
• Webinar organised by LIFE INFUSION: On June 9th 2023, on the framework of the EU Green Week 2023, a webinar was organized to increase awareness and contribute to the public debate surrounding sustainability and the EU Green Deal.
• 6th IWA International Conference on eco-Technologies for Wastewater Treatment. It was carried out in Girona from 26th to 29th June 2023. The main topics discusses were: Emerging technologies and processes, decentralized strategies, resource recovery and safe use, digitalization, economic, environmental, and social footprint.
• 2^nd International School on Water Reuse organised by Universitá di Torino in Torino between September 13^th and 15^th, 2023. The main theme was water reuse from a multidisciplinary and systemic approach to learn about the challenges of water reuse and specific disciplinary insights to improve specialist knowledge.

E1. Project Management

This activity integrates all project management tasks that are allowing LIFE GREEN SEWER to be developed according to the planning established in the proposal, achieving the objectives of the project.

CETIM Technological Centre has the responsibility of full project management. The action ensures the correct project technical and economic progress, making possible the fulfilment of the contractual obligations of the Grant Agreement with the European Union and according to the project’s objectives and work plan.