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Increasingly, circularity indicators for material, energy, and water systems guide circular economy design. While indicators for products made from recycled carbon-based materials are somewhat common, peer indicators for waste nitrogen-derived products are limited. It is important, however, to develop such indicators to guide emerging technologies that transform waste nitrogen into products. In this study, we summarize the nitrogen circularity indicator literature, emphasizing the agricultural and wastewater sectors. Next, we use the Material Circularity Indicator (MCI) developed by the Ellen MacArthur Foundation, to quantify the circularity of products made from waste nitrogen in swine manure. We considered four test cases using different technologies to recover nitrogen from the manure. Our analysis indicates that technologies that seem to increase circularity on the surface may not yield a substantial increase in MCI results. Finally, we discuss the strengths and weaknesses of using the MCI for product-level analysis and further developments.
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Toxicants, entanglement, and mitigation in New England’s emerging circular economy for food waste
Abstract Drawing on research with food waste recycling facilities in New England, this paper explores a fundamental tension between the eco-modernist logics of the circular economy and the reality of contemporary waste streams. Composting and digestion are promoted as key solutions to food waste, due to their ability to return nutrients to agricultural soils. However, our work suggests that food waste processors increasingly find themselves responsible for policing boundaries between distinct “material” and “biological” systems as imagined by the architects of the circular economy—boundaries penetrable by toxicants. This responsibility creates significant problems for processors due to the regulatory, educational, and structural barriers documented in this research. This paper contributes to scholarship which suggests the need to rethink the modernist logics of the circular economy and to recognize the realities of entangled material and biological systems. More specifically, we argue that if circularity is the goal, policy needs to recognize the barriers food waste processors face and concentrate circularity efforts further upstream to ensure fair, just, and safe circular food systems.
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- Award ID(s):
- 1934426
- PAR ID:
- 10392302
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Journal of Environmental Studies and Sciences
- Volume:
- 12
- Issue:
- 2
- ISSN:
- 2190-6483
- Format(s):
- Medium: X Size: p. 341-353
- Size(s):
- p. 341-353
- Sponsoring Org:
- National Science Foundation
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