The overall objective of REDIFUEL is to enable the utilization of various biomass feedstocks for an ultimate renewable EN590 diesel biofuel (drop-in capable at any ratio) in a sustainable manner. REDIFUEL’S ambition is to develop new technologies, solutions and processes to be integrated to reach high conversion efficiencies for renewable fuel production. And, to proof the techno-economic potential to reach a highly competitive production cost level of € 0.90 – 1.00 per litre (depending on biomass source) at moderate production plant sizes, e.g. 10-25 kt/a with further price potential in the future from scaling effects from a high number of installations. The proposed drop-in biofuel contains high-cetane C11+ bio-hydrocarbons and C6-C11 bio-alcohols which have
exceptional performance with respect to combustion and soot-inhibition properties. The environmental and the society aspects are taken into account by a comprehensive Biomass-to-Wheel performance check of the developed technologies and processes.

Specific scientific and technical objectives, main innovations and targeted key results are:

  1. To develop and validate a compact and highly efficient Fischer-Tropsch (FT) synthesis process leading to an unconventional hydrocarbon product pattern with high contribution from liquid olefins in the C5-C10 carbon chain length range.
  2. To develop and validate a selective and efficient hydroformylation and hydrogenation process for the C5-C10 olefin-rich product fraction from the FT synthesis process.
  3. To develop process designs for a small and an intermediate size, fully integrated production plant starting from biomass (bio)syngas to a Drop In renewable EN590 compatible fuel.
  4. To define a blending strategy for (C11+) hydrotreated FT hydrocarbon products and C6 -C11 alcohols.
  5. To set up a fit for purpose test bench for fuel leading parts.
  6. To quantitatively assess the effects of the novel alcohol-enriched biomass-derived fuel, both neat and in optimal blends identified in the project, on the performance and possible emission gains of compression ignition combustion engines representative of the existing European fleets. And to investigate fuel efficiency improvements which can be derived from the cleaner combustion behaviour regarding existing fleets, but also regarding an engine optimization enabled by the new fuel for future long-haul engines and combustion concepts.
  7. To close the loop from fuel to engine development and backwards, via the analysis of the spray and combustion behaviour of the target Alkane-Alcohol mixtures and integration of this in Computational Fluid Dynamics (CFD) modelling.
  8. Optimization of the combustion process with the newly formulated bio-based fuel (and blends formulated thereof) employing a combination of experimental combustion development with Computational Fluid Dynamics (CFD) analyses and single cylinder combustion development methodology. By this, the optimal blend formulation can be identified which runs with the same or better efficiency as standard EN590 diesel in existing-fleet engines without modifications.
  9. By single cylinder engine tests using the optimized fuel definition, it will be derived how a detection of the new fuel can improve the combustion and efficiency behaviour using an adaptive engine controller to adjust the injection settings based on the amount of the new fuel in the used fuel mix. This online calibration change could be realized in future vehicles using a fuel sensor and new control logics, but no additional engine hardware modifications.
  10. In addition, it will be identified how the new fuel as 100% fuel can contribute to increase the engine efficiency from nowadays 46-47% up to 50-51% including engine modifications like cylinder coating, flow optimization and swirl reduction, improvement of stroke to bore ratio and valve timing optimization enabled by the better combustion performance of the new fuel formulation.
  11. To showcase the suitability of the newly developed biomass-derived drop-in fuel for current-fleet diesel engines with a test drive on a chassis dyno and on real roads including PEMS measurements using a Daimler Actross equipped with the latest engine generation (OM471).
  12. To perform a viability performance check of the developed process(es) based on available standards, certification, accepted and validated approaches for Biomass-to-Wheel calculations. Also, to perform a Life Cycle Assessment (LCA) by carrying out an overall impact assessment by the quantification of the environmental impacts along the entire supply and value chain, incl. biomass source, pre-processing, logistics and socio-economic aspects. This requires a comprehensive inventory of all relevant energy flows and emissions created. Next to Biomass-to-Liquid’s (BTL)’s potential for reducing GHG (including land-use), the emphasis will be on its impact on local air quality and human health, considering particulate matter and photochemical ozone formation. The biofuel’s water footprint will be encompassed as well.