Reusing Effluents from Agriculture to unLock the potential of Microalgae

Project Information

REALM

Grant agreement ID: 101060991

DOI

10.3030/101060991

EC signature date 7 June 2022

Start date 1 July 2022

End date 30 June 2027

Funded under

• Food, Bioeconomy Natural Resources, Agriculture and Environment

Total cost

€ 10 225 005,00

EU contribution

€ 8 554 800,75

Coordinated by

NECTON-COMPANHIA PORTUGUESA DE CULTURAS MARINHAS SA
Portugal

Periodic Reporting for period 2 - REALM (Reusing Effluents from Agriculture to unLock the potential of Microalgae)

Reporting period: 2024-01-01 to 2025-06-30

Summary of the context and overall objectives of the project

The REALM project seeks to transform nutrient-rich drainage waters from soilless farms into valuable resources through decentralised microalgae production. This approach enhances resource re-utilisation and profitability for both microalgae production and soilless farming, while addressing the pressing challenges of freshwater scarcity and the environmental damage caused by nutrient pollution. The strategy involves spreading semi-automatic microalgae production facilities near key resource suppliers. Here biomass is produced, concentrated, and shipped to a central processing facility to increase efficiency and cost-effectiveness.
The REALM project aims to overcome critical bottlenecks hindering the widespread commercialisation of microalgae-based products – such as the high production costs – to make these feedstocks more competitive than less sustainable sources. REALM addresses this challenge by focusing on five crucial inputs for industrial-scale microalgal biomass cultivation: water, nutrients, energy, CO2, and labour. To this end, the project focuses on selecting and optimising resilient, productive and commercially relevant strains under continuous cultivation maintained by membrane-harvesting. Cultivation will be supported by novel sensors and A.I.-based predictive models to enhance operational efficiency. A direct air capture prototype will be tested in the validation facilities to deliver 2-5 % CO2 to the cultures. Downstream, the project adopted a biorefinery approach that maximises biomass valorisation and product development. REALM seeks to generate novel bioproducts with rising global market demand, such as biostimulants and biopesticides for agriculture and aquafeed functional ingredients for aquaculture.
The project comprises 16 partners, including five universities, five non-profit organisations, and six companies with complementary expertise that are merging their knowledge to move forward in the microalgae, agriculture and aquaculture sectors. In this way, REALM aims to develop an innovative, sustainable, and highly efficient strategy for microalgae biomass production and processing applicable to all European countries, thus unlocking the potential of microalgae for a thriving European blue bioeconomy.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

The REALM project has achieved significant technical and scientific milestones, successfully validating the feasibility of growing microalgae using soilless agricultural drainwater. Drainwater characterisation revealed substantial variations in nutrient and metal concentrations among the locations where facilities will be built. Finland and the Netherlands exhibited the highest levels of N and P. A total of 21 microalgae strains were tested to assess the feasibility of using microalgae for nutrient removal from drainwater.
Our technical advancements have been focused on efficiency and control. A significant achievement was the successful integration and operation of a Direct Air Capture (DAC) unit for over 3500 hours in microalgae cultivation. This, along with the use of advanced SCADA systems, novel optical sensors for precise growth and nutrient monitoring, and AI-based predictive models, has supported robust, automated operation. In biological optimisation, co-cultivation with custom bacterial consortia or with different microalgae successfully increased growth and enhanced the accumulation of specific metabolites yielding a superior resilience of the culture to higher temperature fluctuations.
Two validation facilities in the Netherlands and Finland demonstrated stable and reliable continuous cultivation under chemostat and turbidostat modes. This operation achieved high biomass productivities while demonstrating effective water treatment, which involved the removal of nitrogen and other pollutants, achieving nitrogen removal rates of 30-55 mgN/L/d and yielding permeate that met discharge compliance standards. Installation of demonstration facilities using open cultivation systems in Portugal and Spain is underway.
The downstream biorefinery pipeline was optimised, achieving high total biomass recovery rates. The valorised fractions, including microalgae biostimulants that reduced mineral fertiliser use in tomato cultivation by 25%, and extracts that exhibited promising biopesticide activity against plant pathogenic oomycetes, hold great promise for the future. Furthermore, ingredients grown in drainwater were confirmed safe for inclusion in aquaculture diets without adverse effects on larval growth. Finally, foundational Techno-Economic Analysis (TEA) and Life Cycle Assessment (LCA) models were established to quantify sustainability and guide future process optimisation.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The REALM project has made significant progress in exploring the potential of microalgae as a more sustainable feedstock. The project is demonstrating the feasibility of using microalgae in agricultural freshwater management, thereby improving water quality and reducing production costs.
A key technical result is the successful validation of continuous cultivation using agricultural drainwater at scale, achieving high nitrogen removal rates while consistently ensuring the treated water meets environmental discharge compliance standards. This outcome provides validated scientific evidence on environmental benefits, directly supporting the EU Green Deal's Zero Pollution Action Plan and the European Ocean Pact's goal of restoring ocean health by mitigating nutrient runoff. Other technical innovations include integrating and operating a DAC unit for CO2 supply, automating several cultivation parameters, and optimising downstream processing to achieve high biomass recovery rates. These efficiencies are crucial for achieving the project's high exploitation target of reducing microalgae production costs by over 50%.
Preliminary results demonstrated microalgae-extracts used as biostimulant that reduced mineral fertiliser use by 25% in tomato cultivation (directly aiding the EU's fertiliser reduction targets). Additionally, the inclusion of microalgae extracts in feeds, confirmed the safety of drainwater-grown ingredients for inclusion in aquaculture diets.
To ensure further uptake and success, key needs identified include full-scale demonstration of the system through the demonstration facilities currently under construction, finalising the comprehensive Techno-Economic Analysis (TEA) and Life Cycle Assessment (LCA) models, and promoting a supportive regulatory and standardisation framework for this circular economy model. At the end, the project will focus on a high-exploitation track by presenting a business case to foster interest among potential stakeholders and increase its impact.

Microalgae decentralised production concept

Circular approach of REALM

Infographic of REALM's work packages