The production of salable co-products can substantially improve the economics for CO2 conversion processes. A new electrified thermochemical process developed by startup Reduciner Oy (Espoo, Finland; www.reduciner.com) combines captured CO2 streams with biochar to produce carbon monoxide, along with activated carbon, a valuable material in water treatment, metals recovery, air purification and many other applications.
Powered by the Reverse Boudouard reaction converting CO2 to CO-rich syngas, the cornerstone of Reduciner’s technology is a proprietary reactor that behaves similarly to an electrically heated rotary kiln, where CO2-to-CO conversion efficiency has climbed above 90% in trial operations. The technology’s only two inputs — CO2 and biochar — can both be sourced from waste streams, while renewable energy sources can power the fully electrified reactor. This enables a potentially carbon-neutral pathway to CO (which can be sold as a fuel gas for industrial processes or as a feedstock for synthetic hydrocarbon production) and activated carbon.
Source: Reduciner
“It’s an important benefit of our process that we don’t need pure carbon dioxide. It can be diluted, enabling, for example, use of a fluegas from an industrial process,” says Eemeli Tsupari, Reduciner chief technology officer and co-founder. For the biochar feedstock, the company has focused on sidestreams from the forestry industry, such as bark and sawdust, but many other biogenic carbon sources have been tested, adds Tsupari.
The company has demonstrated the conversion of CO2 at bench-scale, and plans for a pilot plant are progressing following a €3.6-million funding round. Construction of a subsequent full industrial-scale plant is on the horizon, targeting customers in hard-to-abate industries, such as cement, lime, steel and pulp and paper.
“For instance, in the cement and metal industries, we would receive the captured CO2 from the same industrial player who would be using the produced CO as their fuel, replacing their fossil fuels. Then going forward, as the synthetic hydrocarbon market is scaling up, we want to be part of that market as well, providing our CO as a raw material for synthetic hydrocarbons,” says Johanna Grönroos, CEO and co-founder of Reduciner.