Microalgae biomass production

Algae are a natural renewable resource of unique products, little exploited until now, but which have an important role in solving dietary and health-related problems of future generations worldwide. Microalgae are undemanding and require only sunlight, carbon dioxide, phosphor and nitrogen to grow rapidly. They produce a broad variety of basic chemical substances such as vitamins, fatty acids and carotenoids with high added value potential for the pharmaceutical and food industries.

The Fraunhofer IGB is concentrating activities on two markets in the food supplement sector: natural astaxanthin, a red pigment with antioxidative properties, and highly unsaturated fatty acids (omega-3 fatty acids), which play an important role in human cardiovascular and inflammatory diseases. For the production of algal biomass containing high-value substances we have developed at Fraunhofer IGB a specially designed low cost panel reactor built on the airlift-loop-principle.

Fields of research

 

Process development in photobioreactors

We optimize microalgae cultivation processes in flat-panel airlift reactors developed at Fraunhofer IGB in laboratory scale with the aim of transferring them to outdoor production conditions. For an optimized outdoor process, we have developed an automation concept with simple measurement technology. A scale-up is possible in our pilot plant at Fraunhofer CBP in Leuna.

 

High-value products

For the production of valuable substances, e.g. omega-3 fatty acids (EPA), carotenoids such as fucoxanthin, lutein or astaxanthin, as well as storage products such as oil or starch, we develop one- or two-stage production processes in laboratory scale reactors with the goal of transferring them to outdoor processes. For processing of the valuable products we work out efficient extraction procedures.

 

Algae biomass as a renewable energy source

Storage lipids of algae such as triacylglycerides with the main fatty acids C16: 0, C16: 1 and C18: 1 are suitable for direct energy use, while algae starch can be used for the production of bioethanol. We are looking for suitable algae strains and select growth conditions favoring the formation of storage compounds.

 

Use of Microalgae in organic

Biological pest-repellent ingredients from microalgae and cyanobacteria can be used as ecologically compatible plant protection products. In cross-departmental cooperation, we have developed processes for the production of microalgae with insect repellent and antifungal activity for applications in organic cultivation of cabbage and organic viticulture, respectively.

 

Recycling of nutrients through algae cultivation

For cultivating microalgae we also use residual waste streams from biogas technology, which contain high amounts of inorganic nutrients such as ammonium and phosphate. In this way, we combine microalgae biomass production with nutrient recycling from fluid digestate.