Bioconversion and Upgrading for Sustainable Fuels

CIRCULAIR develops a novel HTL pathway that converts abundant agricultural residues like manure and straw into HTL biocrude as an intermediate product. The biocrude is then upgraded to liquid hydrocarbon fuels with a high share of jet fuel as the main target product. One of CIRCULAIR’s main innovations is the coupling of HTL with wet oxidation (WO) of the HTL process water. Thereby, the HTL process water is cleaned-up and the process heat demand for HTL conversion can be greatly reduced. Ideally, thermo-neutral operation is achieved. The resource-efficient biorefinery concept utilizes green hydrogen and CO₂ evolving from the coupled HTL-WO process to synthesize methanol. Methanol can be used as marine fuel or as a renewable commodity chemical.

The CIRCULAIR concept also foresees the recovery of Volatile Fatty Acids (VFAs) and ammonia from the process water after wet oxidation. The use of HTL solids for soil amendment and carbon sequestration is investigated.

CIRCULAIR will advance the technical maturity of core conversion steps to a technological readiness level of TRL 4 to 5 on a scale from 1 to 9. (TRL 4: Technology validated in a lab, TRL 5: Technology validated in an industrially relevant environment)