AAU Bubble Project: Power2Proteins - Single cell protein production from e-fuel residues

The Power2Protein project is investigating the power-to-liquid fuels/chemicals pathway with a novel process, combining thermal catalytic chemical process for power-to-methanol and bioprocessing for methanol-to-protein. For the power-to-methanol part, the research group of Electro-fuels (Xiaoti Cui) at the AAU Energy has investigated the process through the previous project (Power2met), and built a pilot-plant demonstration (220 ton methanol/year) and also a spin-out company (REintegrate ApS, currently European Energy A/S). From these outcomes, experiences and confidence in e-methanol production has been gained. However, additional optimizations still await for preparing for this first step in order to produce the best possible substrate without inhibiting compounds and cost-effective design for further downstream processing. The subsequent bioprocessing for methanol-to-protein part will be investigated by collaborating with the Department of Bioscience and Chemistry, groups lead by Assoc. Prof. Cristiano Varrone and Prof. Jeppe Lund Nielsen.

In the proposed bubble project, the following research topics are planned to be conducted by the collaborative team:

1) Process design and optimization for power-to-methanol-to-protein, e.g., dynamic operation strategies based on intermittent renewable energy, and possible integrations of the chemical and bioprocessing parts. The optimization will also study the best suitable substrate composition relative to the energy consumption. Preliminary techno-economic evaluation of the designed process will also be conducted, e.g., with a case for protein demand of animal feed in Denmark.

2) Experimental study of bioprocessing for protein production with the crude methanol produced from the pilot plant at AAU Energy, optimal treatment conditions and proper bacteria will be investigated. So far only relatively few organisms have been found to be able to utilize methanol as a substrate (eg. some Pseudomonas species Hypomicrobium vulgare, and Methylococcus capsulatus as well as some yeasts). However, recent studies suggest that new and more efficient strains can still be found in specific environments. The Varrone group has significant expertise in enrichment and isolation of bacteria from the environment for biotechnological application and compare different selection strategies to environmental samples taken from different ecosystems. The best suited growth and operational principles for scaling the process up to industrial proportions will be based on knowledge on the microbial physiology which will be studied by advanced molecular approaches, which is the expertise of prof Jeppe Lund Nielsen’s group. With this approach we will screen for the best conditions to convert methanol into proteins.

3) Collectively the bubble project will cover:
a) Energy optimization of power-to-(best suitable substrate for bioprocessing) (Xiaoti group)
b) Strain selection for the produced substrate
(Varrone group)
c) Growth optimization for conversion of substrate into protein
(Nielsen group)