RUN - RURAL URBAN NUTRIENT PARTNERSHIP
Nutrient communities for sustainable agriculture
Farmers’ Preferences for Fertilizers derived from Domestic Sewage and Kitchen Waste – A Discrete Choice Experiment in Germany
In view of increasing energy and resource scarcities, nutrient recycling from domestic wastewater is a promising way to obtain mineral fertilizers. Given the lacking evidence about the acceptance of recycling fertilizers by the farming sector, we elicited farmer preferences and willingness to pay (WTP) for selected attributes of mineral fertilizers made from domestic sewage and kitchen waste. We conducted a Discrete Choice Experiment with 206 German farmers and fitted a Random Parameter Logit (RPL) model.
Assuming an average market price level of around 300 euros per tonne of N-P-K fertilizer, the choice experiment revealed that farmers not engaged in non-food production such as forage cultivation or renewable energies activities and without farmer-to-consumer direct marketing would accept a recycling fertilizer only together with a financial compensation via price discount of approximately 10%. The average WTP drops considerably if a fertilizer’s heavy metal contents are relatively high and if the absence of drug residues cannot be guaranteed, whereas a customizable nutrient composition and a constant supply availability would have a sales promoting effect.
Farmers’ characteristics can only partly explain the notable heterogeneity of the WTP for the considered fertilizer attributes. Even though the WTP for a recycling fertilizer is on average less than that for a conventional mineral fertilizer, the estimated WTP standard deviations suggest that not all farmers expect a financial compensation via price discount when purchasing recycling fertilizers.
Utai, K., Narjes, M., Krimly, T. und C. Lippert (2022): Farmers’ Preferences for Fertilizers derived from Domestic Sewage and Kitchen Waste – A Discrete Choice Experiment in Germany. German Journal of Agricultural Economics (GJAE) 71 (4);.
Fachgebiet für Produktionstheorie und Ressourcenökonomik
Institut für Landwirtschaftliche Betriebslehre, Universität Hohenheim
Publikation im German Journal
of Agricultural Economics (GJAE)
Dezember 2022
Publikation in "Sustainability" erschienen
Stakeholder Assessment on Closing Nutrient Cycles through Co-Recycling of Biodegradable Household Kitchen Waste and Black Water between Rural and Urban Areas in South India
Agricultural land degradation, urban migration, increasing food demand and waste, and inadequate sanitation systems all affect farmers, local society, and the environment in South India. Joint recycling of biodegradable secondary household resources to close nutrient cycles between urban and rural regions can address all these challenges and thus several SDGs at the same time. Efforts are being made to this end, but many attempts fail. The central research question is, therefore: how can co-recycling concepts be evaluated in this context?
For this purpose, composting plants, biogas fermenters, and a high-tech concept to produce plant charcoal, design fertilizer, and biopolymers are considered. The aim of this study is to evaluate the recycling concepts from the stakeholders’ perspective to avoid gaps between theory and practice. Six expert and one focus group interviews on two successful on-site case studies and 15 online expert interviews with thematic actors were qualitatively evaluated and presented in a social network analysis to identify preferences and indicators for the further evaluation of co-recycling concepts.
The results show that the focus is on mature technologies such as compost and biogas.High-tech solutions are currently still in rudimentary demand but will play a more important role in the future.
To evaluate such concepts, seven key indicators and their measured values were identified and clustered into the categories ecological, social, technical, economic, and connective. The results show that this methodology of close interaction with stakeholders and the evaluation of successful regional case studies minimize the gap between practice and theory, contribute to several goals of the SDGs, and thus enable such concepts to be implemented sustainably.
Fendel, V., Kranert, M., Maurer, C., Garcés-Sánchez, G., Huang, J., & Ramakrishna, G. (2022). Stakeholder Assessment on Closing Nutrient Cycles through Co-Recycling of Biodegradable Household Kitchen Waste and Black Water between Rural and Urban Areas in South India. Recycling, 7(4), 49.
https://doi.org/10.3390/recycling7040049
Institut für Siedlungswasserbau, Wassergüte- und Abfallwirtschaft, Universität Stuttgart
Publikation in "Recycling" erschienen
Juli 2022
Publikation in "Sustainability" erschienen
Biopolymer production from wastewater
flow for a cycle-oriented urban water management
Project staff of the TU Kaiserlautern have published an article in the June issue of "Wasser und Abfall", the magazine of the Bund der Ingenieure für Wasserwirtschaft, Abfallwirtschaft und Kulturbau (BWK) e.V. (Association of Engineers for Water Management, Waste Management and Cultural Construction). From the point of view of RUN, the first results of an acidification of black and brown water are shown and compared with industrial wastewater.
In laboratory experiments, primary sludge, brown water, black water, brewery and dairy waste water were anaerobically acidified to obtain short-chain organic acids that can be used as substrate for biopolymer production. Based on the acidification results of the respective wastewater streams, potential estimates of biopolymer production capacity for Germany were carried out.
Thomas Uhrig M.Sc., Julia Zimmer M.Sc., Florian Rankenhohn M.Sc., Prof. Dr.-Ing. Heidrun Steinmetz (2020): Biopolymerproduktion aus Abwasserströmen für eine kreislauforientierte Siedlungswasserwirtschaft, In: Wasser und Abfall, Issue 6/2020.
Department of Resource Efficient Wastewater Treatment
the University of Kaiserslautern
Publication in "Wasser und Abfall"
June 2020
Biopolymerproduktion aus Abwasser-
strömen für eine kreislauforientierte Siedlungswasserwirtschaft
Projektmitarbeiter der TU Kaiserlautern haben in der Juni-Ausgabe von "Wasser und Abfall", der Zeitschrift des Bundes der Ingenieure für Wasserwirtschaft, Abfallwirtschaft und Kulturbau (BWK) e.V., einen Artikel veröfffentlicht. Aus Sicht von RUN werden die ersten Ergebnisse einer Versäuerung von Schwarz- und Braunwasser gezeigt und mit Industrieabwässern verglichen.
In Laborversuchen wurden Primärschlamm, Braunwasser, Schwarzwasser, Brauerei- und Molkereiabwasser anaerob versäuert, um damit kurzkettige organische Säuren zu gewinnen, die als Substrat zur Biopolymerproduktion genutzt werden können. Ausgehend von den Versäuerungsergebnissen der jeweiligen Abwasserströme wurden Potenzialabschätzungen zur Biopolymerproduktionskapazität für Deutschland durchgeführt.
Thomas Uhrig M.Sc., Julia Zimmer M.Sc., Florian Rankenhohn M.Sc., Prof. Dr.-Ing. Heidrun Steinmetz (2020): Biopolymerproduktion aus Abwasserströmen für eine kreislauforientierte Siedlungswasserwirtschaft, In: Wasser und Abfall, Issue 6/2020.
Fachgebiet Ressourceneffiziente Abwasserbehandlung
der Technischen Universität Kaiserslautern
Publication in "Wasser und Abfall"
June 2020
