Circular nutrient flows for local food production

The project’s context and aim

Soil improvement is one of the key issues for these farmers in order to achieve a large harvest and many crops per square metre and season. Such a high-quality product is in short supply. At the same time, the Gothenburg area has large amounts of horse manure which causes problems and additional costs. The usual way of dealing with horse manure today is to send it for incineration for a fee. This treatment stops biological activity and reduces the amount of nutrients in the final product. Reasons why manure is not used as fertiliser include that it is perceived to be nutrient-poor and difficult to handle, for example it requires a facility where the manure is stored for a year before it can be used. Furthermore, there are a lot of underutilised residues from different types of food production in the city and we want to investigate how they can be used in the production of a soil improvement product.

For society to make a shift towards more sustainable and circular food production, system-level investments are needed. This project is a way to get a process started on a large scale, where nutrients in waste are used to grow food in a circular system, instead of these nutrients being burned or becoming an issue in streams and rivers. The process created through this project will solve several problems and become a good example for the rest of the country, and other countries, of what a technical, logistical and economic solution for sustainable food production can look like. It will also demonstrate that increased self-sufficiency can be achieved by using a circular system based on industrial symbiosis and organic farming.

The local, circular flow also allows for food production with minimal transport of both imported fertilisers and long-distance transport between food production and consumption. Furthermore, the project's analysis of available substrates and matching them to the needs of different flows allows for more optimised bioeconomy systems.