New postdoc in systems analysis group – welcome Verena!


Hej! My name is Verena and I recently started a 2-years-postdoc here at SLU’s Kretsloppsteknik. Rooting in my bachelor and master degree of civil engineering and water management at the University of Natural Resources and Life Sciences Vienna (BOKU), my interests and expertise evolved throughout my doctorate to a more interdisciplinary perspective at the science-society-policy interface. After working on sanitation system planning and modelling in my master thesis, I enrolled in the Transitions to Sustainability (T2S) Doctoral School with its goal of promoting and supporting inter- and transdisciplinary research in the field of sustainable development. My previous research focused on the development and evaluation of coherent policy-options to boost the implementation of SDG 6 at the example of Austria and on the assessment of methods to evaluate interactions between different SDG entities.

Here at SLU I will be supporting the group on systems analysis lead by Jennifer. My work will focus on evaluating different systems for resource recovery and identifying and balancing trade-offs between sustainability aspects related to these systems. If you would like to know more about my work and interests just contact me or approach me for a talk or a fika. I am looking forward to fruitful exchanges and exciting tasks here at SLU. Vi ses!

New Vinnova project: The feed of the future for fish, pigs, poultry and laying hens


We are once again partnering up with a number of stakeholders all through the food production chain, from producers of residual streams, to insect producers, feed producers and farmers to wholesalers in the project The feed of the future for fish, pigs, poultry and laying hens (Framtidens foder för fågel fisk och fläsk, 5F), partially finansed by Vinnova. The project will test and evaluate several innovative feed ingredients, including for example insects, mycoprotein, and blue mussels from the Baltic Sea. The goal is to set up production with sales of pigs, fish, poultry, and eggs from laying hens that have been fed a low climate impact feed containing ingredients that benefit biodiversity. The project takes the results further from the pilot Five Tons of Green Fish which proved that it is possible to raise Swedish rainbow salmon with insect-based feed, which has up to 70% lower climate footprint than conventional feed. We will be the insect knowledge hub in the project.t.


New postdoc in systems dynamic modelling – welcome Erika!


Erika Francisco is originally from Brazil, where she completed a bachelor degree in Environmental Sanitation and a PhD in Chemical Engineering, specifically focusing on biorefineries for reuse and valuation of wastewater for the production of bio-products from microalgae. She has worked as a university lecturer in the Environmental Engineering Department at University of Passo Fundo for three years and as a Postdoctoral Researcher in the project “Food-Energy-Water Nexus Governance” bythe University of Campinas and Belmont Forum.

At SLU, she will be working as a postdoc on sustainable sanitation systems dynamics modelling. She will be developing systems dynamic models for resource recovery systems from urine and wastewater fractions, including modelling outputs related to emissions, water footprints and socio-technical indicators. She will be with Kretsloppsteknik for the next two years.

Factors influencing the recovery of organic nitrogen from fresh human urine dosed with organic/inorganic acids and concentrated by evaporation in ambient conditions


Can we evaporate water from acidified fresh human urine to produce a solid fertiliser? Yes, we can! In our latest article in Science of the Total Environment (STOTEN), my colleagues (Anastasija VasiljevDyllon Randall and Bjorn Vinneras) and I show how human urine can be treated to produce fertilisers with nutrient content similar to that of blended synthetic/mineral fertilisers sold on the market. In fact, we can produce a fully #biobased #urine #fertiliser containing more than 20% nitrogen by dosing fresh urine with organic acids and dehydrating it in ambient conditions. So dig into our article if you’re as fascinated by #urinechemistry as we are, because we also attempt to understand the factors that affect the recovery of nitrogen-containing organic compounds in urine.

Producing fertilisers from urine-derived nutrients is highly relevant in today’s context, where globally the increase in fertiliser prices is affecting food production and causing more global hunger. On the other hand, segregating urine at source and safely #recycling it also one “beyond the business as usual” approach to achieving the sustainable development goal on water and sanitation #SDG6, a goal whose targets we are in serious risk of not meeting by 2030.

We therefore hope to transfer results from our paper to exciting projects such as P2GreeN and REWAISE EU project where urine recycling systems are being piloted in real-world settings!

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.

Recent study on faecal sludge qualities and quantities and potential for resource recovery in Phnom Penh, Cambodia


At the current progress rate, there will probably still be 2.8 billion people world-wide without safely managed sanitation by 2030. Faecal sludge treatment is crucial for safely managed sanitation. To incentivize and increase implementation of sustainable faecal sludge management (FSM), especially in the cities of low and middle-income countries like Phnom Penh, Cambodia, there should be radial shift in viewing human waste as a resource. However, planning data, e.g. on qualities, quantities and fate of faecal sludge after leaving households are, inadequate and lack of accuracy. This study aimed to provide baseline data for effective FSM planning by sanitation stakeholders in Phnom Penh. This was done by characterizing the physical and chemical properties of faecal sludge in Phnom Penh, identifying sources of variation in faecal sludge composition, quantifying sludge volomes generated, transport logistics and resoruce recovery potential to incentivize sustainable management. In total, 194 faecal sludge samples collected during containment unit emptying were analyzed for physicochemical parameters. Interviews were conducted with users and emptying and transportation contractors, together with collection of technical data about on-site sanitation systems. Geographical coordinates of household sampling locations and disposal sites were also mapped.

The results showed that the concentation of many faecal sludge parameters such as nutrients and organic matter are at the lower end of the range reported for other similar cities worldwide, but still higher than the permissible Cambodian wastewater discharge level. The three predictors influencing faecal sludge characteristics included the addition of water during emptying, connection to the urban drainage network and the type of wastewater captured by household containment system. Cheung Ek and Kob Srov wetlands are the main recipients of faecal sludge collected in Phnom Penh with the amount of 18,800m3 and 13,700m3 annually (Figure 1), respectively. The analysis showed that faecal sludge in Phnom Penh contains valuable resources such as nitrogen (6 tons), phosphorus (13 tons) and energy (148-165 GWh) annually. The baseline data would be useful inputs for decision makers and planners in developing action plan for FSM in Phnom Penh and similar cities.

Read the whole papers:

Eliyan, C., Vinnerås, B., Zurbrügg, C., Koottatep, T., Sothea, K., and McConville, J. (2022). Factors Influencing Physicochemical Characteristics of Faecal Sludge in Phnom Penh, Cambodia. J. Water Sanitation Hyg. Development. 12 (1), 129–140. doi:10.2166/washdev.2021.193

Eliyan C, McConville JR, Zurbrügg C, Koottatep T, Sothea K and Vinnerås B (2022) Generation and Management of Faecal Sludge Quantities and Potential for Resource Recovery in Phnom Penh, Cambodia. Front. Environ. Sci. 10:869009.
doi: 10.3389/fenvs.2022.869009

Funding from the Kamprad Foundation will help address issues with mineral precipitation in urine collection systems


Håkan Jönsson and Prithvi Simha were very pleased to hear last week that the Kamprad Family Foundation decided to grant them #funding for a two-year project that will address issues with #precipitation of minerals in #sanitation systems that separately collect #urine. Together with Dyllon Randall (an August T Larsson Guest Researcher at Swedish University of Agricultural Sciences (SLU)), they will develop techniques for preventative maintenance/cleaning of toilets. They also plan to develop technologies that capture mineral precipitates at the toilet, thereby preventing their deposits along wastewater pipes. Much of the work in the project will be done in #collaboration with two housing associations in Stockholm, BRF Understenshöjden and BRF Gebers, where urine-separating toilets were installed more than 20 years ago!

Rich Earth Institute/Brightwater Tools visits SLU



Kim Nace and Ryan Homeyer of the Rich Earth Institute/Brightwater Tools visited Prithvi at SLU last month during their European tour of organizations that research and implement source-separation and nutrient recovery. They met over lunch and had discussions on a wide range of urine-related topics – how we collect urine, how we treat urine using our technologies (urine dehydration/SLU and freeze concentration/Rich Earth), our spin-off companies (Sanitation360 and Brightwater Tools), and how we operate in different contexts (Sweden versus the US; where regulations, funding and support are all different). But more importantly, the discussions really showed how similar our organisations are. For instance, our motivation with creating the spin-off companies are similar (to channel funding back to our research institutes rather than to make profit). It seems that organisations and people working with urine recycling could achieve more by joining hands and collaborating. So we really look forward to continuing the dialogue with the folks at Rich Earth Institute/Brightwater Tools.

Open position postdoctoral research fellow for studies on hygienisation in fly larvae composting


We are looking for a postdoctoral research fellow for our research in fly larvae composting, with a focus on the hygiene of the process as well as of the larvae and the treatment residue (frass-compost) from the treatment of society’s biodegradable waste. The work will be conducted in close collaboration with researchers and doctoral candidates in the group who work on related issues. The focus is to evaluate the degradation of various biological infectious agents such as bacteria (also spore-forming), bacteriophages and prions. The postdoctoral fellow is expected to pursue the following studies: 1) fate of prions in fly larvae composting; 2) fate of anaerobic spore-forming bacteria in fly larvae composting, and 3) study of mechanisms for killing salmonella in fly larvae composting.

Click here for more information.

Visit from CompoCloset founders to discuss urine treatment


The co-founders of CompoCloset, Erica Pugh and Richard Peter, visited SLU to discuss ways in which source-separated urine can be treated on-site. They have developed a composting toilet, Cuddy, that is specifically designed for vanlife that fits in small places like vans, tiny homes, cabins, and boats. They had nice discussions with Prithvi about ways in which SLU, Sanitation360 and CompoCloset could work together; e.g., by integrating SLU/S360’s urine dehydration technology with the Cuddy toilet.  

The Cuddy toilet. PC: Erica Pugh