Phosphorus is a necessary nutrient required for all life. However, it is only found in limited quantities in nature. In a new doctoral thesis at the University of Borås in Sweden, biochar plays a crucial role in developing new methods for recycling and managing this important element.

The research project has a significant relevance to the treatment of municipal wastewater, which generates large amounts of sewage sludge. This sludge contains almost all the phosphorus from the wastewater together with a significant part of the organic matter.

However, this in turn is contaminated by heavy metals, organic pollutants such as pathogens, dioxins, microsites, and antibiotics. At the same time, discussions are ongoing at national and EU level to ban the sludge as it is currently treated from being placed on agricultural land.

Application in agriculture and environmental areas

Biochar is a material that in turn can be used to recover nutrients such as phosphorus, which is very important for agriculture as it is a constituent of fertilizers. At the same time, biochar helps to reduce the amount of harmful pollutants that can otherwise enter the environment. Biochar has caught the eye of industry, but research into its possible applications is still in its infancy.