Abstract

This study assessed the environmental impacts of recycling the plant nutrients in anaerobically digested food waste as fertilizer in agriculture. This was compared with the impacts of using chemical fertilizer, where the food waste was incinerated, producing heat. The study site was a biogas plant in central Sweden and life cycle assessment methodology was used. The impacts studied were primary energy use, global warming potential (GWP), potential acidification, potential eutrophication, cadmium flow to farmland and use of phosphate rock. Use of digested food waste as fertilizer proved to have larger negative results than use of chemical fertilizer in all categories assessed except use of non-renewable phosphate rock. Sensitivity analyses showed that the scenarios were comparable in terms of primary energy use and better for GWP if some improvements in the anaerobic digestion system were made. However, acidification and eutrophication caused by digestate handling and the cadmium content of digestate should still be considered. (C) 2014 Elsevier B.V. All rights reserved.

Keywords

Biogas production; LCA; Digestate; Fertilizer; Food waste treatment

Published in

Resources, Conservation and Recycling
2015, Volume: 95, pages: 1-14

SLU Authors

• Chiew, Yoon Lin

  • Department of Energy and Technology, Swedish University of Agricultural Sciences
    

• Spångberg, Johanna

  • Department of Energy and Technology, Swedish University of Agricultural Sciences
    

• Hansson, Per-Anders

  • Department of Energy and Technology, Swedish University of Agricultural Sciences
    

• Jönsson, Håkan

  • Department of Energy and Technology, Swedish University of Agricultural Sciences
    

Sustainable Development Goals

Ensure sustainable consumption and production patterns


UKÄ Subject classification

Energy Systems
Environmental Management


Publication identifier

DOI: https://doi.org/10.1016/j.resconrec.2014.11.015

Permanent link to this page (URI)

https://res.slu.se/id/publ/64285