This article was published in the resource.co online magazine on 13 November 2024.
A consortium of companies across the Baltic and North Sea are pooling their resources to develop algae-based products using industrial waste nutrients.*
Europe’s northern seas are not in a good state. The Baltic Sea has the dubious honour of being one of the world’s most polluted and exploited seas.
A 2023 report from the Baltic Marine Environment Protection Commission (Helcom) showed barely any improvement in water quality between 2016 and 2021. Industrial wastewater, agricultural runoff, and even corroding WW2-era munitions have all played a role.
Things are not much better in the North Sea. Recent research has shown that the oil rigs installed in the region are linked to decreased biodiversity on the seafloor.
Fortunately, national and EU efforts are cleaning things up, with an eye to a future economy based on marine algae. In November 2022, the European Commission published the EU Algae Initiative to improve the legal and business environment for algae production.
Many European researchers are already finding ways to both grow algae and treat runoff.
“We’re working with wastewater from greenhouses in the Netherlands, aquaculture waste streams in Norway, and textile waste streams in Sweden,” says Bernardo Carvalho, a researcher at GreenCoLab in Portugal.
He is part of an EU-funded research project called Locality that is developing a water purification technology using microalgae and macroalgae. A key part of the project is making the process appealing to local industries.
As Carvalho explains, the project’s approach is pretty straightforward. Algae require sunlight, carbon dioxide, water, and nutrients—often found in domestic and industrial wastewater. These wastewater nutrients, known as ‘side streams,’ are a significant threat to the environment but also potential food for algae, which in turn act as natural wastewater managers by filtering pollutants. The project uses both macro and microalgae in this process.
Macroalgae are classic multicellular marine plants commonly called seaweed, while microalgae, like cyanobacteria, are unicellular photosynthetic organisms. Both play an essential role in absorbing nitrogen and phosphorus from water. Such nutrients, released into the environment by farming activities, when in excess quantities, can cause oxygen depletion in lakes, rivers, streams and the ocean.
Today, over 97 per cent of all algae production comes from Asia, with Chinese production accounting for 57 per cent globally. However, the growth trend in global algae production is not matched by Europe, which currently sits at only 0.8 per cent of the worldwide output, mostly macroalgae.
“There are several major economic bottlenecks for microbiology farming in Europe,” says Malgarida Costa, coordinator of the Locality project and Research Manager at the Norwegian Institute for Water Research in Oslo. She says that modern algae production is relatively new in Europe, meaning setup and production costs are high. This affects Europe’s ability to compete with industries established for decades.
The continent’s multiple and unharmonized national regulations complicate things further. “Navigating these regulations is a major challenge, but learning from experience is also complex due to a lack of standardization and understanding,” said Costa.
Despite these bottlenecks, the EU now boasts the highest number of seaweed start-ups and equity investments in the algae sector, a sign that things may change.
France and Spain dominate EU algae production, while other countries excel in more specialised industries: Ireland in macroalgae and Germany and Italy in microalgae. Therefore, we may see further growth of this phenomenon in the rest of the EU. There is already a growing interest in this type of biomass, especially from a sustainability perspective.
However, Locality aims to solve the pollution problem and use the algae biomass produced through this process as a foundation for sustainable algal products, including algae-based food, aquaculture feed, bio-fertilisers, nutrients, and algae-based dyes.
In short, that same biomass is converted into products that can be helpful to the local industries. Ideally, the same companies that employ microalgae as tools for wastewater treatment in this area will be the first beneficiaries of these products, creating a truly circular system.
Chemical checks
The algae are cultivated in coastal waters and sourced from wild stocks before being processed in biorefineries. The initial step, however, is to determine which algae species work best with the waste nutrients, and the algae used in Locality are chosen in various ways. “We’re getting seaweed mostly from two sources: either locally harvested, especially from partners experienced with that industrial process, or grown in aquaculture,” explained Carvalho.
However, selecting microalgae is a different procedure. Carvalho explains that the microalgae are going through a ‘screening process.’ In the project’s partner institutes in Norway and the Netherlands, different algae strains are evaluated and chosen based on productivity, growth rate, and their ability to remove nutrients or pollutants from waste streams.
One of the most promising aspects of this project is producing new types of algae-based animal feed. However, all the biomasses harvested must first undergo a very rigorous chemical check for toxic compounds or pollutants before processing. Different waste streams also require distinct approaches. “The aquaculture waste stream, for example, is usually less toxic,” says Carvalho. “We are primarily talking about removing nitrogen and phosphates, but greenhouse streams may also contain traces of pesticides. Luckily, algae usually cause a high degree of degradation of these compounds.”
As Carvalho points out, one sector that faces significant environmental challenges is the textile industry, as industrial dyes release metals into the water. However, he assures, “It’s done on a case-by-case basis, and everything is thoroughly analysed beforehand.”
Labour intensive
Animal feed products made entirely from algae may become more popular in the future, but for now it’s more feasible for the market to use labour-intensive algae only as an additive. “In terms of animal-based feedstocks, […] currently, we’re not looking to replace all the ingredients with algae, but we aim to add them first as a biostimulant. For example, algae can promote crop resistance or enhance the fish’s immune system in an aquaculture setting. This reduces the use of chemical pesticides and antibiotics,” he said.
But the industry still faces a final barrier once these products reach the consumer. “In Europe, consumer awareness and acceptance of this kind of product are relatively low, forcing the industry to educate the consumer and deviating from its central role, production,” said Costa.
Nevertheless, these processes already show market potential, especially in the Baltic and North Sea areas, as they combine wastewater treatment with the production of biomass used by local industries.
Costa is also optimistic these obstacles can be overcome. “The diverse possibilities of algae applications offer a reduced market risk and increase the sector’s resilience,” she said. “However, I think it’s also fair to acknowledge that realizing the full potential of this market will require continued innovation, investment, and research efforts. If we overcome these major hurdles, I believe that the algae sector can be a cornerstone for Europe’s sustainable economy.
This article was written by Massimiliano Saltori.