Dried algae for biodiesel production. (Photo: Descubre Foundation)

Dried algae for biodiesel production. (Photo: Descubre Foundation)

Ateam of researchers from the University of Almeria (UAL) has patented a method for dehydrating microalgae and producing cheaper biofuel. By applying a technique for drying the algae, scientists from the biotechnology group managed to reduce by more than one third the breeding ground of these organisms without increasing energy expenditure in the process of obtaining biodiesel.

One problem that occurs during the production of biofuels is the low concentration of microalgae cultures, i.e., there is plenty of water and few producing organisms. To improve this concentration, scientists at UAL have come up with a way to eliminate the volume of water until microorganisms dry forming a kind of paste (biomass) that later will be subjected to various treatments to obtain biofuel.

The reduction of the culture medium facilitates the work in the later stages of the process, and the lesser amount of material to be processed leads to a cut in power spending and in the equipment used, Descubre Foundation revealed in a press release.

The new technique patented by UAL is an alternative to centrifugation, which is a common dehydration process. “…centrifugation entails a higher energy expenditure than that generated by the biodiesel itself, so it is not a viable solution,” said Tania Mazzuca, head researcher of this project.

“Moreover, it is a contradiction to produce clean energy using other conventional, not so green methods,” the scientist added.

One advantage of the developed process is that glycerol, which is one of the products obtained when converting the algae oil to biofuel, is used to “dry” the algae through an osmosis process. This not only increases the sustainability of the manufacturing process, but also reduces its cost.

The researchers found that, in tests conducted to demonstrate the effectiveness of the patented technique, over a third of the culture medium is removed in the first hour of the process. Moreover, after two hours the reduction is between 55 and 65 percent.

The patent is part of the research project “Potential use of neutral lipids obtained from algae as raw material to produce biodiesel” is funded by the Ministry of Economy, Innovation, Science and Employment of Junta de Andalucía.