Aliahmad, Abdulhamid
- Department of Energy and Technology, Swedish University of Agricultural Sciences
Abstract
Conventional sanitation systems contribute to environmental issues, such as greenhouse gas emissions, eutrophication, and resource depletion. Urine recycling, a form of source separation, offers a pathway toward circular sanitation by recovering nutrients and reducing emissions. Despite its clear environmental benefits, large-scale adoption remains limited. This thesis investigates how urine recycling can support sustainable sanitation transitions and identifies the environmental, institutional, and social factors that facilitate its adoption. A transition-focused framework combining life cycle assessment (LCA), technological innovation systems (TIS), and system dynamics modeling (SDM) was developed and utilized to analyze environmental performance, system functions, and adoption dynamics.
Results showed that source-separated sanitation systems, which include urine recycling, can reduce the carbon footprint of conventional wastewater treatment by up to 20% and even achieve carbon-negative results under optimized configurations. However, large-scale adoption remains limited due to regulatory uncertainty, an underdeveloped market for urinederived fertilizers, and weak institutional support. The TIS analysis revealed that establishing a clear regulatory framework – such as product certification for urine-based fertilizers, financial incentives for early adopters and municipalities implementing collection systems, and well-defined coordination among utilities, regulators, and farmers – greatly improves adoption. Without these measures, the innovation system tends to stall. SDM simulations also indicated that large-scale adoption depends on reinforcing feedback among institutional support, social visibility, and system reliability, with adoption accelerating once public awareness crosses a critical threshold.
By operationalizing the integrated LCA–TIS–SDM framework that links environmental outcomes with socio-technical dynamics, practical recommendations are obtained for decision-makers and water management organizations on how certification, operational reliability, and incentive design can be combined to transform pilot projects into functioning urban systems. In conclusion, urine recycling emerges not only as an environmental innovation but as a strategic path to transform sanitation systems into circular, climate-adapted solutions.
Keywords
Source separation; Urine recycling; Circular sanitation; Nutrient recovery; Life Cycle Assessment; Technological Innovation System; System dynamics modelling
Published in
Acta Universitatis Agriculturae Sueciae
2025, number: 2025:92
Publisher: Swedish University of Agricultural Sciences
SLU Authors
UKÄ Subject classification
Water Treatment
Publication identifier
- DOI: https://doi.org/10.54612/a.ms2ndhdmba
- ISBN: 978-91-8124-076-4
- eISBN: 978-91-8124-122-8
Permanent link to this page (URI)
https://res.slu.se/id/publ/142493