Environmental sustainability of phosphorus recycling from wastewater, manure and solid wastes

Abstract

Phosphorus (P) is an important critical material essential for crops cultivation and animal husbandry. Effective phosphorous recycling is considered one of the most significant factors in alleviating its criticality. However, despite the importance of phosphorous recycling, its sustainability is not studied extensively. This paper aims to answer the question if recycling of phosphorus is an environmentally sustainable option. To address this problem, two issues are analyzed in this paper: energy consumption and greenhouse gas (GHG) emissions in phosphorous recycling. The analysis was performed by simulating mass and energy flows in the global phosphorus supply chain (from mining to recycling) in order to understand and analyze its environmental impact in 2000-2050. The results of simulation show that around 82% of recycled phosphorous originates from manure. Moreover, the calculations indicate that about 70% of total GHG emissions from phosphorous recycling is caused by wastewater processing. In addition, the results show that phosphorous obtained from recycled wastewater constitutes only 2% of the whole amount recovered in the recycling process. Therefore, the obtained results show a clear need for a detailed analysis of the sustainability of phosphorous recycling processes. Moreover, the analysis of scenarios of phosphorus consumption indicates that GHG emissions increase slowly in the mining phase and grow exponentially in the recycling stage.The main finding of this paper contradicts the general opinion about environmental friendliness of recycling. It shows that phosphorus recycling is not a sustainable solution in a longer perspective.

Pathways to Water Sector Decarbonization, Carbon Capture and Utilization

“…Their results indicated that sludge-based phosphate fertilizers appeared to have higher environmental impacts than mineral phosphate fertilizers production, mainly due to their consumption of large amounts of electricity and reactants needed to recover phosphorus, and their low phosphorus content in comparison with phosphate rocks. Qualitatively similar conclusions were reported by Golroudbary et al (2019). On the contrary, Tonini et al (2019) suggested that the environmental impacts of recovering sewage derived P may be up to 81% less than mining P containing rock.…”

Rationality of using phosphorus primary and secondary sources in circular economy: Game-theory-based analysis

“…In line with the concept of circular economy, we consider the estimated value of phosphorus recycling will increase by up to 50 % in the next 12-15 years (Golroudbary et al, 2019;Scholz and Wellmer, 2018). Moreover, we assume that there is no difference for a decision maker to choose primary or secondary sources.…”

“…The management policy of phosphorus supply chain in Europe is based on national policies of the Member States which differ with respect to economic benefits and environmental impact as well as resource scarcity and the advancement in the implementation of circular economy model (Stahel, 2016). In addition, the motivation for sustainable use of phosphorus in Europe is driven by the aspiration to implement the principles of circular economy (Golroudbary et al, 2019;Nesme and Withers, 2016). Therefore, recycling or recovery of phosphorus from waste streams has been proposed as a possible approach to managing its sustainable use.…”

Liquid Cattle Manure Effect on Corn Yield and Nutrients’ Uptake and Soil Fertility, in Comparison to the Common and Recommended Inorganic Fertilization

“…At the same time, non-renewable resources like phosphate rocks, which are used in the industry of P fertilizers, are expected to become scarce in the future (Gasparatos et al 2019;Li and Marschner 2019). Furthermore, the mining processes disturb the environment (Golroudbary et al 2019;Grigatti et al 2015).…”