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REsidual soft WOod conversion to high characteristics drop-in bioFUELs

Periodic Reporting for period 1 - REWOFUEL (REsidual soft WOod conversion to high characteristics drop-in bioFUELs)

Reporting period: 2018-06-01 to 2019-11-30

Biomass is increasingly considered as an alternative to fossil oil to address the issues of climate change and resources depletion and independency in the EU. However, direct substitution is not possible and advanced processes are needed to efficiently convert biomass into drop-in intermediates and end products. Lignocellulosic sugars are an attractive resource for these processes and an evolution beyond traditional sugars as they can be produced from a wide variety of resources and do not compete with food or feed production.
The main technical challenges in the development of biomass to fuels technologies are the compatibility of biomass pre-treatment and fuel production technologies and of the produced biofuels with existing transport infrastructures, in particular in aviation. Moreover, public acceptance further challenges the deployment of biofuels.
The REWOFUEL project aims at overcoming these challenges. The value chain is developed on residues from the forestry industry, an abundant resource regarded by the public as favorable for technological applications. The targeted fuels are bio-derived versions of existing and widely used high-performance gasoline and jetfuel constituents currently derived from fossil oil. The targeted fuels derive from a single biochemical intermediate, bio-isobutene (bio-IBN) which serves as a direct replacement of fossil isobutene (IBN), a commodity chemical.
The REWOFUEL approach of wood deconstruction followed by direct fermentation to isobutene, a gaseous hydrocarbon, and its final conversion into liquid fuel components is a true technological breakthrough that solves a number of technical and commercial issues throughout the value chain. Moreover, dedicated activities specifically assess valorization opportunities of all side products and waste streams of the core processes to further improve the competitivity and environmental impact of the value chain. Valorization as energy, in materials (bitumen) and agriculture (animal nutrition and fertilizers) are investigated in detail.
The overall goal of the project is therefore to demonstrate the performance, the reliability and the environmental and socio-economic sustainability, of the entire value chain for the transformation of forestry residues into sustainable, high performance liquid fuels. The project is focused on renewable and sustainable gasoline and aviation fuel aiming to demonstrate that they can be produced efficiently and within specifications that are compliant with existing fuel norms and infrastructures. The outcome of the project will be to provide the backbone for a subsequent first of its kind flagship project converting around 350,000 tons of wood residues into fuels.
Project management allowed good alignment and cohesion of the members of the consortium as well as sound risk management thanks to the regular meeting of the steering board and the executive committee.
Optimization of the 3 core processes is performed in close collaboration at process interfaces and with residual streams valorization partners thereby integrating intermediate products compatibility at the heart of the optimization of individual processes. New process parameters for wood deconstruction have been established in order to ensure high yield as well as compliance with lignin and sugar specifications imposed by downstream uses. New fermentation strains with improved performances were developed by evolution in continuous cultures as well as metabolic engineering. The fuel production process was adapted for the use of bio-IBN and the specific targeting of gasoline components or jetfuel.
Process scale-up activities included the upgrading of the wood hydrolysis demo to enable the concentration of hydrolysates and resulted in the production of more than 10 tons of residual wood hydrolysate (RWH) containing lignocellulosic sugars. These products were delivered to the fermentation pilot for production of first batches of bio-IBN. Samples of wood hydrolysis effluents and fermentation broth were collected and analyzed in view of their valorization. In particular, lignin samples were shipped and used in the manufacture of bitumen while fermentation derived microbial proteins were qualitatively confirmed in their prospective use in animal nutrition. The design of a bio-IBN conversion pilot was also completed.
Concerning sustainable aviation fuel, the activities confirmed the potential of the fuel components targeted and led to the presentation of the REWOFUEL pathway at the bi-annual ASTM meeting as a first step in the certification process. Concerning gasoline fuel qualification, blends displaying high renewable content while still being compliant with the European fuel norm were identified.
Process engineering studies progressed towards the definition of a standalone integrated process solution in preparation of a site-specific case study during the next reporting period. The bases of the socio-economic and public acceptance studies were also established. In particular key stakeholders were identified and classified and the major public acceptance issues were identified. Business plan activities just started at the end of the first period and allowed preliminary work on economic analysis templates.
Finally, dissemination activities provided communication material (presentation video, website, visual identity, slides, roll-up, flyers and social media activity) and focused on presentation of the project at 11 conferences and in 12 articles, public reports and press releases.
REWOFUEL allowed so far high sugar yields from wood deconstruction with a lignin production showing good compatibility with bitumen blending. High concentrated hydrolysates, a favorable trait towards compatibility with bio-IBN fermentation, can now be produced. Strains capable of sustained growth and bio-IBN production from wood hydrolysates were developed as well as new strains capable of sustained bio-IBN production from individual sugars contained in the wood hydrolysates. This will be advantageous for optimization of global conversion yields and economics. However, a residual inhibitory effect is still observed with softwood-derived hydrolysates and is a focus of present work.
Upscaling activities have shown a good compatibility of RWH with the bio-IBN production equipment, allowing a successful scale-up to the demonstration plant during the second reporting period. The co-produced lignin showed good compatibility with its use as a bitumen blend stock at targeted levels. Bio-IBN batches derived from traditional sugars during benchmarking have shown good compatibility with catalysts used for its conversion into fuels which in turn displayed a promising impurities profile and characteristics allowing to achieve the targeted goals of easy-to-blend, high performance fuel components. Scale-up of the conversion will be a key activity of the second reporting period.
The project is on track for demonstrating the feasibility of a new value chain for the conversion of residual feedstock into advanced liquid biofuels with increased yield and favorable energy and greenhouse gas balances. This work is performed with the clear objective of a first of its kind deployment in the EU thanks to the inclusion of industrial actors at each stage of the value chain and shall enable significant social and economic impacts in terms of job creation, economic growth and safe and affordable energy supply.
Sekab's Biorefinery Demo Plant located in Örnsköldsvik (Sweden)
Global Bioenergies's Laboratory, Pilot and Demo equipment for sugar to isobutene fermentation
Scheme of Oligomerization and Hydrogenation of bio-Isobutene to iso-Octance
Feed screw with wood chips from containers at the Biorefinery Demo Plant
Upgrading and detoxification at the Biorefinery Demo Plant