Self-Powered Bioelectrochemical Nutrient Recovery for Fertilizer Generation from Human Urine

Stefano Freguia, Maddalena E. Logrieco, Juliette Monetti, Pablo Ledezma, Bernardino Virdis and Seiya Tsujimura
Additional contact information
Stefano Freguia: Advanced Water Management Centre, The University of Queensland, St. Lucia, QLD 4072, Australia
Maddalena E. Logrieco: Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino (TO), Italy
Juliette Monetti: Advanced Water Management Centre, The University of Queensland, St. Lucia, QLD 4072, Australia
Pablo Ledezma: Advanced Water Management Centre, The University of Queensland, St. Lucia, QLD 4072, Australia
Bernardino Virdis: Advanced Water Management Centre, The University of Queensland, St. Lucia, QLD 4072, Australia
Seiya Tsujimura: Faculty of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan

Sustainability, 2019, vol. 11, issue 19, 1-10

Abstract: Nutrient recovery from source-separated human urine has been identified by many as a viable avenue towards the circular economy of nutrients. Moreover, untreated (and partially treated) urine is the main anthropogenic route of environmental discharge of nutrients, most concerning for nitrogen, whose release has exceeded the planet’s own self-healing capacity. Urine contains all key macronutrients (N, P, and K) and micronutrients (S, Ca, Mg, and trace metals) needed for plant growth and is, therefore, an excellent fertilizer. However, direct reuse is not recommended in modern society due to the presence of active organic molecules and heavy metals in urine. Many systems have been proposed and tested for nutrient recovery from urine, but none so far has reached technological maturity due to usually high power or chemical requirements or the need for advanced process controls. This work is the proof of concept for the world’s first nutrient recovery system that powers itself and does not require any chemicals or process controls. This is a variation of the previously proposed microbial electrochemical Ugold process, where a novel air cathode catalyst active in urine conditions (pH 9, high ammonia) enables in situ generation of electricity in a microbial fuel cell setup, and the simultaneous harvesting of such electricity for the electrodialytic concentration of ionic nutrients into a product stream, which is free of heavy metals. The system was able to sustain electrical current densities around 3 A m –2 for over two months while simultaneously upconcentrating N and K by a factor of 1.5–1.7.

Keywords: bioelectrochemical system; urine; nutrient recovery; microbial fuel cell (MFC); air cathodes (search for similar items in EconPapers)
JEL-codes: O13 Q Q0 Q2 Q3 Q5 Q56 (search for similar items in EconPapers)
Date: 2019
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (4)

Downloads: (external link)
https://www.mdpi.com/2071-1050/11/19/5490/pdf (application/pdf)
https://www.mdpi.com/2071-1050/11/19/5490/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jsusta:v:11:y:2019:i:19:p:5490-:d:273388

Access Statistics for this article

Sustainability is currently edited by Ms. Alexandra Wu

More articles in Sustainability from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().