CONTEXT

Photobioreactors (PBR) have been widely researched and used in biomass microalgal culture for more than two decades, but most of them were just used in laboratories or in pilot or experimental bases. There were only few of them being real used in industrial or commercial algal production. Production rate was not economically sufficient due to oxygen built up in the culture medium, overheating inside the closed system, system complexities or insufficient enlightment… etc. All these limitations had to be faced before scaling up PBR into real commercial production and that is an aim of the present invention to provide an homogeneous enlightment in the volume of the reactor.

TECHNICAL DESCRIPTION

The technology concerns a sunlight guide module for a PBR  including a chamber of reaction, the module consisting in
– a concentrator arranged outside the chamber to concentrate the solar light in a concentrated beam
– a diffuser (optical fibers) in the chamber of reaction
– and a system between the concentrator and the diffuser to homogenize the concentrated beam before it enters the diffuser.
It has been shown that the concentrator can resutl in a very high solar flow at the center of the concentrator spot where the temperature is too hot for the medium; homogeneizatin is necessary to avoid this phenomenon.
Said module may be duplicated in a PBR.

BENEFITS

The problem of the incorporation of enlightening structures inside a reactor indeed presents automatically the double weakness to perturb the flow and to allow possibly the fixation of microalgae.
Here the mixing and the mass transfer remain excellent thanks to the design and the gazosiphon (all these points are already characterized and calculated)
Dicofluv works with low light densities which limits the adhesion of algae which is often due to the synthesis of polysaccharides generated by the strong densities.

INDUSTRIAL APPLICATIONS

This innovation could be used for bio-energy (energy production from biomass or hydrogen), agriculture (production of vegetal proteins, biomass for aquaculture) and environment (waste water treatment or C02 capture).
Said thermal management system is limited neither to PBR nor to thin PBR. Any reactor of various geometries exposed to thermal problems may be equiped.

DEVELOPMENT STAGE

Various systems have been tested. Modelisation have shown the real advantages of the modules. The two teams involved in these developments have very complemetnary skills; PBR on one side and thermal management and solar energy on the other side.

For further information, please contact us (Ref 03256-02)