Abstract: 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.

Abstract: A bioreactor (1, 2, 3) and its use for the conversion of organic residual and/or waste materials into an organic nutrient solution with a proportion of at least 10% plant-accessible mineralised nitrogen relative to the total nitrogen content of the nutrient solution, with a reaction tank (5), where the reaction tank (5) has an input feed (6) through which suspension (4) can be introduced into the reaction tank (5), and where the reaction tank (5) has an outlet feed (7), through which the suspension (4) can be discharged from the reaction tank (5), where the carrier element (10) has at least one inner and one outer settlement surface (11), on which ammonifying and/or nitrifying bacteria can collect.