This project aims to produce a new generation of potent organic fertilizers, based on the recycling of farm and forest residues. Surplus materials such as wood waste, straw, or digestate are subjected to a pyrolysis process and transformed into biochar, a porous solid with a high carbon content. In a subsequent impregnation process, the chars are upgraded by immobilization of nutrients in the porous structure. This is done by soaking the chars with liquid organic residues (e.g. animal manure, other nutrient rich biogenic liquids). These so called advanced biochar (ABC) based fertilizers will be used as a soil amendment in growing annual food crops and trees in forests and urban settings. The production process considers several feedstocks, all are residue materials relevant to Norway or Germany. The production will be optimized by greenhouse experiments with fast-growing vegetable crops, evaluating yields, nitrate retention and nitrous oxide emissions. Best-outcome ABC-fertilizers in terms of yield increase and positive environmental effects are then chosen for the production of a large amount of fertilizer. These will be tested in the field in Germany, recording crop yields and greenhouse gas emissions. Norwegian experiments consider the effect of the ABC-substrates on tree growth when applied to the root zone in plantation pits of trees, both in forests and in urban areas.
Throughout the entire project, a large amount of data will be collected. This includes composition and properties of feedstock and product, production conditions and effects of the fertilizer on plant growth, crop yield, and greenhouse gas emissions. A detailed mathematical analysis of the collected data will be performed in order to reveal dependencies and influences. This knowledge can be used to achieve a successful and more efficient fertilizer production process.
An open access database will be set up, in which information on biomass types, sources and properties relevant for fertilizer production can be stored. This is intended as a tool for end-users to match supply and demand of biogenic residues. This database will initially contain information collected within the project, but will be open to the contribution of third parties and maintained beyond the project duration.
The fertilizers are expected to be more effective than conventional fertilizers while significantly reducing negative effects such as nitrate leaching and water pollution. The transformation of residues into valuable products provides economic chances for farmers. Furthermore, carbon is stored in the soil and greenhouse gas emissions are reduced. An economic assessment and life cycle analysis with a focus on the CO2 balance will be used to quantify these benefits. Results will be disseminated to the scientific community in relevant journals and on conferences, but most importantly to interested end-users and policy makers in workshops where practical guidance is given.
The project is sponsored by the Federal Ministry of Education and Research. In the project TEER works together with NTNU Trondheim, Geisenheim University and Ithaka Institute. The main task for TEER will be the production and the characterisation of the biochar.