Green biomass - protein production through bio-refining
DCA rapport, nr. 93, 2017
Af Hermansen el al
The report summarizes our present knowledge on the bio-technical as well as economic issues in relation to value creation of green biomass in Denmark through high value protein production. The report describes the availability and quality of relevant green biomass, the environmental impact related to the crop production, the mass balances in the bio-refining processes, the feeding value of the protein recovered as well as the remaining fibre-fraction, prospects of the recovered proteins for human food, and operational costs . While a vast amount of knowledge exists or is in progress on these issues, also at all steps there is lack of knowledge to evaluate with a high certainty the overall economic and environmental consequences in case this technology is to be implemented.
First and foremost there is need for the bio-refining process to run at a commercial scale to obtain better knowledge on resource use and efficiency. There is a need to figure out the practical possibilities of using the protein paste as input in wet-feeding systems for pigs, since this will influence energy demands in the process to a high degree. Likewise there is a need to investigate how best to utilize the high moisture residual juice for energy recovery in biogas production to counteract the energy use at the factory level. As regards biomass supply in relation to environmental impact there is a need better to understand how long lasting grass or grass-clover fields can be established and maintained without losing nitrate and carbon. Likewise, there is a need to explore the potential of using cover crops as feedstock supply and - related to that - the environmental impact of new types of cover crops and management practises. Finally, there is a need to explore the possibilities of extracting other valuable components from the green biomass, upgrade proteins for human consumption and/ or upgrade fibre for higher value products in order to improve the overall profitability of the bio-refining process.