Hybrid PhD course on Safe nutrient recycling and management


We at Kretsloppsteknik are currently giving a hybrid (onsite/online) course on Safe nutrient recycling and management (10 credit) within the
research school Sustainable systems for food, energy and biomaterials (SSFEB). The aim of the course is to give the student knowledge in current waste and wastewater management techniques, with focus on technologies for plant nutrient recovery and reuse. Today, 75% of all biodegradable solid waste is landfilled or dumped and 90% of all wastewater generated is either not treated or only partially treated. In cases when the waste is treated, treatments are not focused on recycling, but rather removal, of plant nutrients, as they can otherwise risk to pollute the environment. If the plant nutrients in the waste and wastewater were collected they could replace 25-50% of the virgin resources used for production of chemical fertilizers used in agriculture. Looking at waste and wastewater as resources is a paradigm shift, and for this shift to happen new technologies and management systems are required. When closing the loop of nutrients there is a risk of recycling unwanted substances as well, e.g. heavy metals and pathogens. Upon completion of the course the student should know the flow of waste and wastewater in society, possible treatment methods for closing the loop of nutrients and the risks associated with closed loop systems, as well as methods for mitigating circulation of unwanted substances.


Picture from our last seminar, with two participants being onsite and four participants joining online from India, China and Rwanda.

Final Policy Briefs from the SPANS project


In October 2022, the SPANS project had its final seminar in Kampala, Uganda. The five-year project financed by the Swedish Research Council aimed to improve knowledge related to adaptation and innovation in Sanitation Planning. In particular it explores technical and societal readiness of Alternative Nutrient-recovery Systems. The seminar highlighted the outputs of the project in terms of building knowledge on technologies for resource-recovery, understanding opportunities for implementing such systems and developing a serious game to promote safe resource recovery. All project results can be found on the website: https://www.slu.se/en/departments/energy-technology/projects/kretslopp/spans/

The team also used the seminar to launch the three policy briefs that have been developed in the project:

Bedömning av näringsflödenas cirkularitet i Okanagan Bioregion, BC Kanada


Begreppet ‚ÄĚcirkul√§r biobaserad ekonomi‚ÄĚ har blivit en viktig pelare i en ny generation politik som f√∂rv√§ntas l√∂sa den nuvarande h√•llbarhetskrisen. Att g√• mot en cirkul√§r biobaserad ekonomi √§r avg√∂rande beroende p√• biologiska och tekniska processer som kan √•terf√∂ra v√§xtn√§ring – fr√•n anv√§nda biobaserade produkter till produktion av mat, foder, fibrer, br√§nsle mm.

Näringsflödesanalyser kan hjälpa till att identifiera drivkrafter till ohållbara system och möjligheter att gå mot mer hållbara system. Som en del av ett bredare projekt för livsmedelssystem i Okanagan Bioregion, BC Canada, analyserade vi flödena av kväve, fosfor, kalium och magnesium för att hjälpa intressenter i regionen att bättre förstå nuvarande nivåer av näringscirkularitet och hur den kan förbättras.

Assessing the Circularity of Nutrient Flows in the Okanagan Bioregion, BC Canada


The concept of “circular biobased economy” has become an important pillar of a new generation of policies that are expected to solve the current sustainability crisis. Moving towards a circular biobased economy crucially depends on biological and technical processes capable of recirculating plant nutrients ‚Äď from used biobased products back to the production of food, feed, fibre, fuel, and so forth.

Nutrient flow analyses can help identify drivers of unsustainable patterns and opportunities for moving towards more sustainable patterns. As part of a broader food system design project in the Okanagan Bioregion, BC Canada, we analysed the flows of nitrogen, phosphorus, potassium, and magnesium to help stakeholders in the bioregion better understand current levels of nutrient circularity and how it could be improved.

Full-scale urine drying trials at SLU


This week, the Environmental Engineering group at SLU starts its full-scale urine drying experiments. The group has designed and built 6 household-scale urine drying prototypes for the experiments. Over the coming months, every day, these units will be drying 24 litres of urine. The biggest challenge so far has been to collect enough daily fresh urine to feed the prototypes. We thank all those who have donated urine so far, and hope that these donating  keep coming. Your donations can potentially help revolutionise sanitation!

                                       Urine donation points at toilets across the Department of Energy & Technology, SLU;                     PhD Candidate Prithvi Simha eager to get the experiments started in our Hygiene Lab