The goal of the project is through a combined approach to develop a novel continuous consolidated bioprocess concept for the hydrolysis and fermentation of lignocellulosic feedstocks. The technologies will improve the competitiveness of second generation fuel production processes and thus enable future secure and sustainable energy supply for the transport sector. In the new process concept, previously developed efficient hydrothermal pre-treatment technology will be applied to obtain a high consistency raw material stream, which will be prehydrolyzed (liquefied) at high temperature by thermostable enzymes. In the consolidated bioprocess, the amount of externally added enzymes will be significantly reduced by exploiting an organism, capable of producing a set of lignocellulose hydrolyzing enzymes. The externally added thermostable enzymes will carry out a rapid initial liquefaction, thereby providing the micro-organism with a readily accessible and homogeneous substrate.
The concept of combining added thermostable enzymes and consolidated bioprocessing will enable a high feedstock adaptation as well as a significant reduction in process time and cost combined with a full processing of all the carbohydrates. After optimizing the individual process stages, the novel consolidated bioprocessing technology will be tested in laboratory and pilot scales.
The main scientific objectives are:
- Improvement of the set of thermostable enzymes for the liquefaction and prehydrolysis stages
- Improved cellulases with higher catalytic performance
- Synergistic complementation of the thermostable enzyme system with enzymes produced by the fermenting organism (consolidated bioprocessing)
- Enhanced understanding of the underlying mechanisms of rate limiting factors in lignocellulose hydrolysis
- Optimization of the co-fermentation of C5 and C6 sugars in the consolidated bioprocessing
The main technological objectives aim at reducing the production costs by:
- Development of high consistency liquefaction and consolidated bioprocessing technology
- Reduction of the costs of externally added enzymes by integration of consolidated bioprocessing
- Development of a novel high consistency continuous process specially designed for lignocellulosic feedstocks
- Reduction of ethanol production costs by integration of the consolidated bioprocess to energy production (CHP)