The COLDEP system considerably improves the performance of microalgae culture in raceway:

  • Circulation of water at low energy cost.
  • Degassing of O2 and thus suppression of the inhibition of productivity normally induced.
  • Harvesting microalgae without damaging their cell structure and concentrating them up to 100 times.
Circulation - dissolved gas management

Culture of microalgae in an open basin

A COLDEP column makes it possible to fully manage the culture of microalgae, as well as to recarbonize the medium by injecting CO2 and ensuring total dissolution over the entire height of the column. It is also possible to inject nutrients into the column, thus ensuring their efficient dispersion.

Electricity consumption per m³ of water circulation in a raceway

Maximum circulation rate in the basin

Maximum circulation rate in the basin

Regulated rate of O₂ in the water (instead of 40 mg/L without degassing by our system)

Harvest - Concentration - Biosecurity

Preconcentration of harvest with a small amount of water

By a flotation mechanism and thanks to the height of the water column, performance is increased. It is a very good way to preconcentrate a culture of microalgae before a centrifugation step for example.


Average concentration of microalgae harvested from cultures between 0.01 and 0.2 g/L

Electricity consumption per kg of dry matter extracted


Reduction of bacterial load

less viral load

The above results were obtained with diatom algae (Navicula directa), with Nannochloropsis and with Scenes of music. What's more, Dunaliella salina is harvested at a concentration of 60 g/L each day with a COLDEP system.

Particle extraction by the COLDEP system also makes it possible to trap bacteria and viruses, thus ensuring the biosecurity of the installation. Water clarification also improves access to light, and therefore promotes photosynthesis.

we did it

Our references