A viral inactivation device including at least one continuous viral inactivation reactor having an inlet, an outlet, and a tubular flow path. The tubular flow path includes a set of alternating turns that form a serpentine pattern between the inlet and the outlet.

A bioreactor (1, 2, 3) and use thereof for converting organic residual and/or waste materials into an organic nutrient solution with a proportion of at least 10% plant-available mineralized nitrogen relative to the total nitrogen content of the nutrient solution. A process for preparing an organic nutrient solution is also provided, as well as an organic nutrient solution, use of an organic nutrient solution as an absorbent for carbon dioxide storage, use of an organic nutrient solution as an agent for binding carbon in plants and soils and to a nutrient production and carbon dioxide storage system.