Petrobras considers producing biodiesel from microalgae

Petrobras has been working on the development of pioneering technology for the production of biodiesel from microalgae—an alternative to oil-derived fuels used in cars or any other diesel-powered vehicles.

In an interview granted to Agência Brasil, Juliana Vaz, Biotechnology Manager at Petrobras's Research Center (CENPES), mentioned the pioneering nature of the project and said she expects it helps build a more sustainable future. “It's an avant-garde  project, innovative in Brazil and soon to be made available to everyone.”

Produced from renewable sources (among which soybean oil, animal fat, and cottonseed oil), this biofuel emits less pollutants than diesel does. Biomass is produced from microalgae which is used to extract the oil, which then serves as the raw material.

“The biodiesel produced has been subject to laboratory testing for quality under the standards set by the National Oil, Gas and Biofuels Agency (ANP), and the preliminary results proved promising,” Juliana Vaz said.

A major advantage when it comes to microalgae is the fact that it is not seasonal and its production does not depend on specific conditions, like soil properties. It allows “virtually weekly” harvests, with a productivity rate up to 30 times as high as the biomass made from land vegetables. “Microalgae have a productivity rate considerably higher than that of soybeans and sugarcane,” the expert said.

Benefits for the environment

The production of biodiesel from microalgae brings along with it ecological benefits that contribute to the reduction of carbon dioxide in the air—one of the causes of greenhouse effect, one of today's biggest environmental concerns.

Each ton of microalgae used for the production of biodiesel may remove up to 2.5 tons of carbon dioxide from the air, “a much higher rate than that of other plants normally used for the production of biodiesel—be it from soybeans or sugarcane,” Vaz said, noting that carbon dioxide is subsequently used in the production of a substitute for fossil fuels.

Production scale

Research studies started on a small scale, with a photobioreactor created by CENPES scientists themselves. Today, production is being tested on a slightly larger scale in the city of Extremoz, in Rio Grande do Norte state, with the support of the Federal University of Rio Grande do Norte (UFRN). “The place has open tanks with storage capacity of 20 thousand liters, where microalgae are grown and their productive potential can be assessed, along with its quality and the properties of the oil produced,” Vaz went on to say. This stage is likely to take another 2.5 to 3 years.

In the next phase, the culture should add up to 50 to 100 hectares in open tanks. “That would be a semi-commercial phase, conducted so that we can ascertain whether there are conditions to produce this fuel on commercial scale and competitively. That's when the strategic stage of cost analysis begins, in order for us to determine if it can be introduced into the market,” she explained.

Also under research is the use of microalgae in the production of aviation biokerosene (BioQAV) in partnership with the Federal University of Rio de Janeiro (UFRJ). “Studies were largely based on the control over the cultivation for the production of oil, which, once produced, may serve a wide range of purposes, including BioQAB,” the scientist said.

Translated by Fabrício Ferreira