AlgaEU
AlgaEurope 2026
4BlueTech
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Track #10
4BlueTech
The cascade biorefinery model — extracting pigments, then oils, then proteins, then using residual biomass for energy or fertiliser — transforms what was a single-commodity algae operation into a multi-revenue system yielding €8–15/kg blended value versus €0.8/kg raw biomass.
Cascade concept based on Wageningen UR biorefinery model (Benemann et al., 2014; Draaisma et al., 2013). Actual value depends on purity achieved at each stage. The protein fraction is typically >50% of total mass and therefore dominates both mass yield and cost structure.
Municipal wastewater carries 30–60 mg/L total nitrogen and 5–15 mg/L total phosphorus — both problematic (eutrophication) and valuable (recovered nutrient). Microalgae remove N and P through luxury uptake into biomass at efficiencies that exceed conventional tertiary treatment.
NovAlgae (PT) and Phycoloops (ES) both demonstrated 97% N removal with Spirulina outdoor raceways at municipal wastewater treatment plants (2020–2022).
LCA values in kg CO₂-eq per functional unit (1 kg protein equivalent). Green = net negative (carbon sink). Negative values indicate avoided emissions via displacement of conventional products.
Based on Vanthoor-Koopmans et al. (2013) and Pérez-López et al. (2017) LCA reviews. The cascade biorefinery achieves net negative by combining CO₂ utilisation (1.8 kg per kg biomass), wastewater N/P displacement, and biogas energy recovery from residual biomass replacing grid electricity.
Post-extraction biomass residue (30–40% of input mass) fed to anaerobic digesters produces biogas (55% CH₄) and digestate rich in ammonium nitrogen. Recycling digestate as algal growth medium closes 60–70% of the nitrogen loop, reducing external fertiliser purchase cost by €40–80/t biomass produced.
EU industrial zones (steel, cement, paper) emit CO₂ concentrations of 5–20% — ideal for direct algal sparging. The Ghent Port Authority is piloting a 20 ha algae production hub co-located with ArcelorMittal's Ghent steelworks, targeting 800 t/year biomass on zero-cost CO₂ under EU ETS framework.
4BlueTech's Circular CO₂ Architecture
4BlueTech designs the complete loop: industrial CO₂ capture → algal cultivation → cascade biorefinery → residue digestion → nutrient recycle → back to algae. At each stage, both energy and materials are accounted for in a verifiable carbon and nutrient mass balance — enabling ETS carbon credit claims, Scope 3 emission reductions for industrial partners, and high-value algal products that justify CAPEX independently of any carbon subsidy.