Coupling the cultivation of microalgae with agricultural biogas production
At a glance
- Project leader : Dr. Dominik Refardt
- Project team : Prof. Dr. Urs Baier, Prof. Dr. Christian Ludwig, Adrian Pulgarin
- Project budget : CHF 180'000
- Project status : completed
- Funding partner : EU and other international programmes (COST Action / ES1408 - EUALGAE), SNSF (COST / Projekt Nr. C15.0116)
- Project partner : Ecole polytechnique fédérale de Lausanne EPFL
- Contact person : Dominik Refardt
Biogas production by anaerobic digestion is an established
technology that allows farmers to generate more income from biomass
waste and closing nutrient cycles. These synergies can be extended
even further if microalgal cultivation is added to produce
algae-based bioproducts. The side-products of biogas production,
namely CO2, waste heat, and digestate, are used to increase culture
productivity and lower production costs. Products from microalgae,
such as feed and feed additives, can again be used in the
agricultural sector, which closes material cycles and extends the
value chain for the biogas operator.
We propose to take this synergistic approach a step further and focus on issues, which so far have received less attention. Is it possible to produce biomass of sufficient quality so that it can be used as feed or feed additive? To this end, we take advantage of our large in-house photobioreactor to scale up laboratory experiments and test, whether microalgal biomass of feed-grade quality can be produced while relying on the above mentioned side products. We also investigate to what degree pests and contaminations affect the robustness of continuous cultivation and what measures can be applied to stabilize it. Furthermore, we will determine whether waste heat can be used to prolong the cultivation season in a Swiss climate. Finally, the legal aspects of producing algae-based feed will be researched and documented.
This project is carried out in the framework of the European COST Action ES1408 EUALGAE and financed by the Swiss National Science Foundation. The PhD student carrying out the project is employed by the Zurich University of Applied Sciences and enrolled at the Ecole polytechnique fédérale de Lausanne.