The project entails the conversion of biomass residues, and particularly agricultural residues, to middle distillates using thermochemical conversion routes. The novelty is the use of molten salts to liquefy the biomass, followed by a pyrolysis step and a final hydrotreatment step to remove bound oxygen.
Where are we now with it?
We have arrived at month 30 of the project and made considerable progress, both in the technical and social domain.
The most suitable molten salts have been selected and tested for biomass liquefaction, with very positive results.
Upper limits regarding the process window (e.g. temperature) for selected molten salts have been determined experimentally and supported by advanced thermodynamic models, and mitigation measures for the formation of gaseous salt decomposition products have been established.
The subsequent pyrolysis of the biomass source in the molten salt using both advanced analytical pyrolysis and experiments in larger set-ups has shown to lead to remarkably and intriguing product selectivities, particularly when using wood.
Encouraging results were obtained with lignins and good liquid yields have been obtained as well. The current focus in the technical domain is on the hydrotreatment of the products obtained by pyrolysis, the integration of the concept in a bench-scale unit and the valorisation of the side streams using electrochemical approaches. Critical issues like pumpability and corrosiveness of molten salt/biomass mixtures have been investigated.
Also, a good start has been made with process modelling of the overall concept using advanced software for the design of a full-scale plant, including integration possibilities with existing biomass conversion plants. Within the social domain, key stakeholders have been identified and barriers for the introduction of biofuels to the markets have been identified.
A project can only be successful with excellent collaboration between the partners. Despite the COVID pandemic, which is hampering progress considerably due to limited or even complete inaccessibility of laboratories, we have been able to maintain good communication by online progress meetings including social activities (among other an escape room battle), the organization of a very successful online expert workshop on the hydrotreatment of bioliquids and intense contacts of our communication group with a partner project on the organization of a spring school in 2021.
A number of these activities and the impact of COVID on project progress and the well being of our researchers is also provided in the newsletter.
I hope you enjoy reading the newsletter! Please sign up if you have not done so already.