Sustainability of phosphorus supply chain : circular economy approach

Abstract

Access to non-renewable natural resources is becoming more difficult and expensive. It is due to the growing demand triggered by industrial and agricultural development. That is the reason why several research studies have shed light on the circular economy as an approach helping to ensure sustainability and minimize the criticality linked to the use of many raw materials. One of the materials playing a pivotal role in enabling the growth of agricultural production is phosphorus (P). It originates from non-renewable natural resources and is subject to supply risk due to the unequal geological distribution of its natural resources. Countries poorly equipped with its resources are becoming more vulnerable to changes in phosphorus availability and price indices. Therefore, the significance of phosphorus criticality is pushing for efforts to achieve a steady supply of phosphorus and conserve the material value.

While phosphorus conservation is the main objective of the circular economy, previous studies lack the assessment of circularity transitions in the phosphorus chain to tackle the environmental and social challenges. Also, in regions such as the European Union (EU), high reliance on imports still exists despite the availability of secondary phosphorus. These aspects contribute to the complexity of the phosphorus circular economy.

Assessment of the environmental and social consequences of the phosphorus circular economy is needed to raise awareness of both benefits and costs associated with the circularity transitions. This research aims to analyse the sustainability of the phosphorus supply chain in the circular economy approach. This dissertation presents the dynamics model of the phosphorus supply chain. The model includes the environmental and social sub-systems necessary to assess phosphorus circularity and its impact on the environment and society.

The main findings reflect the complexities involved in the phosphorus circular economy. Results show that phosphorus circularity can reduce the reliance on imports by providing secondary phosphorus. Environmentally, it exacerbates the GHG emissions and energy consumption. Socially, phosphorus circularity can help to achieve several social targets. However, it demonstrates a paradoxical behaviour towards the social issues raised regionally. These burdens associated with the transition to phosphorus circularity model justify decisions that on the face of it appear irrational taken by regions using imported phosphorus instead of recycling it.