Shell eyes biohythane potential in Brazil

Brazil is attracting growing investment to convert by-products from its biofuel industry into emerging types of low-carbon fuels, as firms seek to take advantage of the country's vast renewable energy potential.

UK-based Shell, Brazil's top private-sector oil producer, is studying the conversion of organic residues produced by the sugar and ethanol industry — namely vinasse and filter cake — into biohythane, a gaseous blend of biologically derived hydrogen and methane. Shell is using technology developed by Unicamp, a public research university in the state of Sao Paulo.

Shell plans to spend 6mn reals ($1.24mn) over the next four years, including construction of a biohythane pilot plant that would be operated by university staff until potentially being scaled up to industrial production levels by Shell.

The production of sugar and ethanol generates large quantities of byproducts, such as filter cake and vinasse, that can be used as soil enhancers and substitutes for inorganic fertilizers.

These organic residues also have great potential for Brazilian fuel production, such as cellulosic, or second-generation (2G), ethanol, which is made with bagasse — the biomass from the sugarcane crushing process — as well as discarded tops and leaves from the cane harvest. Shell's effort aims to expand use of these byproducts to biohythane production.

The commercial potential of biohythane could signal "a new era of bioethanol," the company said.

Scientific studies on biohythane are relatively recent, mostly less than 10 years old, but the process in already promising, Unicamp researchers told Argus. Hythane itself is a blend of 10pc hydrogen and 90pc compressed natural gas, which is mainly composed of methane. Its renewable version, biohythane, is biologically produced through anaerobic steps.

Shell's investment in biohythane comes as the outlook for 2G ethanol improves in Brazil after early technological bottlenecks were cleared. Brazil's biggest sugar and ethanol producer Raizen, a joint venture between Shell and domestic conglomerate Cosan, is investing heavily to expand capacity for the advanced biofuel at its 34 mills.

Biohythane's relationship with 2G ethanol gains further significance from the involvement of Unicamp professor Goncalo Pereira, who was a founder and served as technical manager at GranBio, the first advanced ethanol producer in Brazil.

"Our sector thrives on partnerships like this between anchor companies and scientific study centers," Pereira said. "It is interesting to see how some of these companies have relocated large resources from oil exploration into the energy transition."

Shell's investment helps fulfill gas regulator ANP requirements for companies operating in Brazil to spend 1pc of their gross revenue on research, according to the team.

Pereira leads the biohythane project in partnership with professors Marcelo Carazzolle and Gustavo Mockaitis at Unicamp's Genomics and BioEnergy Laboratory.

The Unicamp team faces two major obstacles: keeping the process stable and scaling it to an industrial level, Mockaitis said.

"Shell saw this challenge and understood that our team can, if not solve it, make a lot of progress in figuring it out," he said.

By Vinicius Damazio