Microalgae: raceway ponds and photobioreactors
These microscopic plants are found in rivers, lakes and oceans. In order to grow they need sun, water and carbon dioxide. The idea is to inject the captured CO2 into ponds of microalgae, and the biomass thus produced can be transformed into biofuel (the most critical application of all), serve for the treatement of water, or the production of high added-value molecules for food and health.
Another method consists in injecting CO2 into photobioreactors, closed reactors in which a selected strain of microalga is exposed to optimal conditions (temperature, pH, light intensity…) to grow.
raceway ponds (left) and an example of photobioreactor (right)
Another solution that is being considered is biocatalysis– the reproduction of natural phenomena using enzymes to stimulate a chemical reaction and convert CO2 into valuable molecules (lipids et oxygenate compounds) that can be applied to the pharmaceutical industry, hydrogen production and, ultimately, biofuel production.
If the processes to produce microalgae are already effective, the field of biocatalysis on the other hand is only at a stage of research.