Recycling sludge in agriculture? Assessing sustainability of nutrient recovery in Italy

Using a hybrid multi-regional input–output approach, we traced sustainability footprints of a nutrient recovery strategy from sewage sludge applied in Italy. We then compared the results with the most common landfilling practice. Overall, accounting for indirect global upstream effects, using sewage sludge for organic fertiliser production generates more jobs and reduces more greenhouse gas emissions than landfilling. By contrast, landfilling stimulates the whole economy more, generating higher indirect turnover and reduces energy carrier use more. Finally, we accounted for uncertainties in these results using an error propagation method based on Monte Carlo simulations.