ALG-AD - Creating value from waste nutrients by integrating algal and anaerobic digestion technology

Project Summary

What is ALG-AD?

ALG-AD is a Interreg NWE funded project in which new technology is being developed to take excess waste nutrients produced from anaerobic digestion of food and farm waste to cultivate algal biomass for animal feed and other products of value.

ALG-AD brings together a group of scientists and engineers from 11 different partners in four countries across North West Europe. These academics are working together with industry to develop a circular economy solution to create wealth from waste.

Why is the project necessary?

There is an urgent need to develop sustainable food and farming.  

North West Europe is a densely populated and intensely agricultural area. It thus contributes disproportionately to food and farm waste produced in the EU each year.

Increasing amounts of food and farm waste are processed using anaerobic digestion (AD). AD converts waste to biogas used for energy and a liquid nutrient rich digestate, most of which is returned to land as a biofertiliser.

However, there are strict limits on the amount of digestate which is allowed to be put back on agricultural  land. Strict limits are imposed with EU legislation and so-called Nitrate Vulnerable Zones. This is increasingly creating excess unwanted nutrients. 

The ability to use these excess nutrients to produce new products presents a circular economy solution. 

How can ALG-AD help?

ALG-AD combines algal and AD technology.  Microalgae, mainly photosynthetic microorganisms will be cultivated, converting the unwanted nutrients into biomass. The cultivated algal biomass is rich in protein and other useful compounds, and can be used to generate sustainable animal feed products and other useful bio-products.

What is ALG-AD doing?

ALG-AD has completed three pilot facilities construction at 3 distinct ‘real life conditions locations in North West Europe: Devon (UK), Ghent (Be) and Brittany (Fr). Each facility used local conditions to grow the algae and record results. Information from the three pilots is used to generate Decision Support Tools. These tools together with a demonstration to stakeholders promote the adoption of the new technology.

The valorisation of produced algal biomass will be achieved through the animal feed preparation. The process of hydrolysation of algal biomass with the assessment of pathogens and heavy metals level, permitting to use this biomass for the animal (piglet and fish) nutrition trials.