Sustainable algal biomass products by cultivation in waste water flows

Algae are predicted to play an important role in tomorrow’s bioeconomy. The technical goal of the project was to develop enhanced algal cultivation processes utilising waste flows and to increase the overall material and energy efficiency of algal processing for biodiesel and biogas production. The project produced new knowledge on the boundary conditions for cost efficient algal cultivation and productivity. The use of algae as a tertiary treatment of municipal waste water, such as the utilisation of waste water flows from biowaste handling, was assessed with positive results. Process concepts based both on CO2 uptake and (waste) organic carbon were assessed. In a Nordic climate the utilisation of spill heat is requisite and with restricted available daylight in the winter time, an alga’s ability to shift from autotrophic to heterotrophic growth provides a potential strategy for algal cultivation in Nordic circumstances. The fractionation of algal residuals for biopolymers is a new research area with potential long term impact in the bioeconomy sector. Cost efficient Integrated production concepts still need to be developed, as premises to successful business models. It is apparent that an economically viable algae-to-biodiesel commercialization will initially depend on government subsidies and the future price of oil, in addition to optimized biomass yields. However, algae to biofuels is globally a topical sector with a high interest from several stakeholders. The markets are likewise global. From the biofuel point of view, air traffic is particularly interesting, as this sector will probably need to rely on liquid fuel still during the next decade.