Dear WalNUT friends,

Welcome to the fifth edition of the WalNUT project newsletter! 

We open this issue with the recent visits at the two Spanish pilot plants in Zamora (Castilla y Leon) and Ourense (Galicia).

In October, during the WalNUT General Assembly, partners visited the pilot site in Ourense, run by CETAQUA. This pilot recovers soluble nitrogen from reject water flows. CETAQUA walked us through the plant and showed how the pilot operates to recover soluble nitrogen from waste flows, which is subsequently repurposed in the production of bio-based fertilisers. 

In November, the consortium gathered to visit the pilot plant managed by VEOLIA and CARTIF at Zamora. This case study focuses on treating local industrial wastewater, using a two-stage microalgae cultivation process that removes contaminants and produces biomass, which is then dried into a fine powder to create nutrient-rich, sustainable bio-based fertilisers. The system is explained by the VEOLIA and CARTIF team in this video.

Our “A chat with WalNUT” series of video interviews continues with three new experts: 

- Alejandro Saldarriaga Vásquez, Innovation Engineer at Veolia, introducing their work on WalNUT’s business models and exploitation pathways

- Isabel González García, PhD Environmental Engineer at Itacyl, examining the challenges of adopting bio-based fertilisers (BBFs) in Europe 

- Massimo Pugliese, Associate Professor at University of Torino, introducing the methodologies used in field trials and the current stage in the testing of bio-based fertilisers provided by the different pilots. 

A new journalistic article is online! “Cultivating change” explores the potential of bio-based fertilisers as a more eco-friendly alternative to conventional products, highlighting how the WalNUT project is working to overcome market and regulatory barriers at EU level. 

Happy holidays and stay tuned for a brilliant 2025!

Thank you and enjoy your reading!

The WalNUT team

Do not miss the latest episodes of A Chat with WalNUT - watch them now!

In October, WalNUT partners visited two pilot plants in Spain as BBF production accelerates!

The WalNUT General Assembly, held last October in Santiago de Compostela, celebrated the project's progress as it reached its 36-month milestone, with just 18 months remaining. The event was hosted by CETAQUA Galicia and highlighted results from five pilot projects nearing completion, alongside discussions on fertiliser effectiveness tests and upcoming field trials. On the second day, participants visited CETAQUA’s pilot plant in Ourense, Spain’s first center dedicated to water and environmental innovation, focusing on transforming wastewater plants into biofactories and promoting sustainable solutions through circular economy principles.

Bio-based fertilisers offer eco-friendly alternatives but face barriers to adoption. This journalistic article examines their potential as substitutes for conventional products. Despite their promise, challenges such as high production costs and outdated regulations persist. The article highlights the WalNUT project as an active example working to address these issues and accelerate the adoption of this sustainable technology.

The CYPRUS 2025 Conference will explore sustainable solid waste management through innovative technologies, covering topics like recycling, waste-to-energy, and circular economy practices. Experts from various sectors will share advancements in municipal waste management.

Click here for further information and here to register!

The WalNUT Platform is an interactive online tool developed by the National Technical University of Athens, aiming to facilitate matchmaking between stakeholders involved in the value chain of nutrient recovery from waste water streams. Its objective is twofold: 

1. Promote industrial symbiosis among the WalNUT stakeholders and EU-27 Member States. 
2. Provide a structured knowledge repository focused on agricultural nutrients from secondary resources within and outside Europe, covering the entire value chain.