New Installation Up & Running at SLU’s urine-separating toilet


Exciting news! At the Swedish University of Agricultural Sciences (SLU), where all three of Sanitation360’s founders have studied and now work, a new bathroom installation has been in the works. And as of last week, after an incredibly impressive effort by Jenna, version 2.0 is finally ready to be used on the 5th floor at the Department of Energy and Technology at SLU in Uppsala, Sweden.

The bathroom contains one of Laufen’s urine-diverting toilets, which we’ve connected to our urine concentrator – and now we’ve also added our own addition to the flush system. Usually, both urine and 220 ml of flushwater end up being diverted into the urine collection tank, per flush. Whilst this is no issue in terms of purity, it is an issue in terms of energy usage later on in the urine to fertilizer process.

Urine consists of about 95% water, which contains no nutrients. Therefore, our urine concentrator is designed to effectively remove/evaporate the water, leaving us with the nutritious 4% of the urine. This is already a large amount of water to remove and with additional flushwater in the system, it rapidly increases the energy requirements. To make it more sustainable, we want to reduce, and favourably completely stop, any flushwater from entering the urine collection tank and instead divert it to the wastewater pipe. This is exactly what our new installation now does – thanks to Jenna and David Fredriksson at Davitor AB.

There is now a sensor that detects incoming flushwater and triggers the valve to the urine collection tank to close. The system also has a reactor with a level sensor to enable automatic pumping of urine into to the concentrator, where the urine is dried.

So if you ever happen to be in Uppsala, make sure to give it a visit and let us know what you think of it!

The white container on the right side is our concentrator which the urine is first diverted into and then dried into a nutrient rich mass. Attached to the wall behind it is our newly installed system which detects when someone is flushing and closes the valve to the urine collection tank. The program showcased on the computer shows how the different valves and sensors are working together to achieve this. Lastly, you can see Laufen’s beautiful urine-diverting ”Save!” toilet which we are big fans of!

An urgent call for using real human urine in decentralized sanitation research


The choices we make matter. The choices we make as scientists can significantly impact society. In this perspective article published in Frontiers in Environmental Sciences, Caitlin Courtney, Dyllon Randall and I focus on one such methodological choice in decentralized sanitation research: whether to use real human urine or synthetic/artificial urine for experimentation.

For various reasons, many studies opt for synthetic urine over real human urine, relying on recipes for making synthetic solutions that mimic real urine. Using synthetic solutions as stand-ins for real fluids is a legitimate scientific method, and one that is not uncommon in wastewater research. But exclusively using synthetic urine can present methodological challenges, especially when protocols for its preparation are not well-established and validated against real urine. This article highlights some of the compositional and property differences between synthetic urine and real urine, and the implications of these differences on experimental outcomes and their real-life implications.

We hope this article sparks a dialogue within the research community on the benefits of using real urine in experimental research. We strongly encourage researchers involved in this field to collaborate in establishing standardized terminology, definitions, methodologies, and best practices for sanitation-related research involving human urine.

If you are interested in furthering this effort, please do reach out to us!

Simha, P., Courtney, C., & Randall, D. G. An urgent call for using real human urine in decentralized sanitation research and advancing protocols for preparing synthetic urine. Frontiers in Environmental Science, 12, 1367982.

Oliver is back at SLU for his thesis project!


My name is Oliver. Currently, I am in my final year of studies at Tampere University of Applied Science. My association with the urine drying team dates back to the summer of 2022. During that period, I was involved in researching various methods for the acidification of urine. The primary objective of this research was to prevent the process of enzymatic urea hydrolysis, thereby preserving nitrogen in urine. I have now returned to SLU to write my BSc thesis, where I will focus on exploring techniques for the removal of organic micropollutants. These pollutants, can have significant environmental impacts, especially in aquatic environments. Through my research, I aim to contribute to the development of more sustainable and effective waste management practices.

Microbes In Focus: Isis Conroy’s Return to SLU


Hi, I am Isis Conroy. I am in the final year of my bachelor’s degree in environmental engineering at Tampere University. Last year, I was at SLU working alongside Natnael Demissie with lab duties relating to his doctoral thesis which evaluated the effect of UV and peroxide on antimicrobial-resistant bacteria and their genes. This year I have returned to do my own thesis working on a project that aims to standardize a methodology for assessing urea hydrolysis in urine by utilizing bacterial urease rather than jack bean urease. In both my work and hobbies, I enjoy microbiology, microscopy, and mycology. In my free time, I am a mushroom guide, teach microscopy lectures to children, and I enjoy spending time outdoors. I will be at SLU until I present my thesis in early June.

The AirCloset project!


The SLU Urban Futures hub in Ultuna has granted funding to three interdisciplinary projects focusing on the Urban Food-Energy-Water nexus, one of which is called “The AirCloset” that will be led by Prithvi Simha from SLU, Sweden and Gert van der Merwe from NUST, Namibia.

The Air Closet and Granurin Technology:
The project will pioneer the development of a toilet that separates and dehydrates urine using solar-thermal energy. This not only provides a sustainable solution for sanitation in informal settlements but also presents a unique opportunity for recycling urine into a great fertilizer – Granurin.

Granurin, a Fertilizer Revolution:
Granurin, with its 20% nitrogen content, represents a revolutionary step in sustainable agriculture. Simha and his colleagues at SLU have successfully developed a technology to dehydrate urine, creating these safe fertilizer pellets that can potentially replace synthetic fertilizers. This not only contributes to circular food production but also opens up a global avenue for local food security enhancement.

Impact on Urban Informal Settlements:
Taking the technology a step further, the project aims to implement urine drying in urban informal settlements, where over a billion people reside without access to basic services. By providing a solution that integrates sanitation, agriculture, and economic empowerment, The Air Closet challenges the status quo, striving to uphold the promise of Agenda 2030 – “leave no one behind.”


Call for papers in BMC Environmental Sciences on Nature-Based Solutions in wastewater management


BMC Environmental Science is calling for submissions to a speciall issue on Nature-based solutions in waste-water management. Prithvi Simha from our research group, who is an editorial board member of BMC Environmental Science, is serving as one of the three guest editors of this special issue, alongside Sartaj Ahmad Bhat from Gifu University, Japan and Dai-Viet N. Vo from Nguyen Tat Thanh University, Vietnam. 

  • Submission Status: Open
  • Submission Deadline: 2 September 2024
The coastal wetlands around Wrightsville Beach, North Carolina. Credit: Hank Carter.

Why Nature-Based Solutions Matter: Nature-based solutions offer a sustainable alternative to conventional wastewater treatment methods. From centuries-old practices to cutting-edge innovations, this special issue explores how natural processes and ecosystems can revolutionize wastewater treatment. Imagine vertical flow constructed wetlands minimizing treatment footprints and coconut coir and biochar enhancing pollutant removal. Add real-time data analysis and automation, and you have a recipe for ecological resilience, nutrient recycling, and sustainable water use.

How You Can Contribute: We’re calling for submissions from researchers, experts, and enthusiasts passionate about shaping the future of wastewater management. Whether you’re conducting groundbreaking research, implementing nature-based solutions in the field, or exploring the potential of innovative technologies, we want to hear from you! We’re looking for original research, case studies, and reviews that explore the efficiency, scalability, and effectiveness of nature-based solutions.

Submission : Before you dive in, check out our submission guidelines at

Spread the Word: Help us spread the word! Share this announcement with your colleagues, fellow researchers, and anyone interested in the intersection of environmental science and sustainable practices. Let’s create a diverse and impactful collection of insights.

FoodsecURe: Food security through better sanitation


FoodsecURe: Food security through better sanitation is a NRC funded 4 year research project (2023-2027) that targets the small-scale producers around the outskirts of Bahir Dar city who also participate in the on-going EU H2020 funded project “Healthy Food Africa” (HFA). FoodsecURe is coordinated by NIBIO with Dr Divina Gracia P. Rodriguez as Project Manager, with partners including the Kretsloppsteknik group at the Swedish University of Agricultural Sciences (SLU), the Norwegian University of Life Sciences (NMBU), Norges Vel, Bahir-Dar University (BDU), and Amhara Regional Agricultural Research Institute. BDU office of the Healthy Food Africa project, Bahir Dar City Water Supply and Sewerage Authority, and the Bureau of Water and Energy are key stakeholders and members of the Advisory Committee of the project from the Ethiopian side.

Kick-off workshop for the FoodsecURe project at SLU


It has been a pleasure to host the kick-off meeting of the FoodsecURe project over the past two days at SLU – Swedish University of Agricultural Sciences. During the next four years, our project will evaluate how safely hashtagrecycling hashtaghumanurine can improve urban sanitation as well as livelihoods of small holder farmers in Bahir Dar, hashtagEthiopia, where urine-separating toilets already exist today.

With alkaline urine dehydration as the focal technology, we will examine how hashtagtechnological, hashtaghealth and hashtagsafety, hashtagsociocultural, hashtageconomic, hashtaginstitutional barriers to recycling urine in Bahir Dar can be overcome, and how new sanitation value chains can be developed and sustained over time. This is likely going to be a complex and tough undertaking, but our hashtagmultidisciplinary team of experts are keen to take on this challenge together.

Degradation of poly-L-lactic acid biopolymer films in Ca(OH)2-dosed fresh human urine


We have recently published a paper in Resources, Conservation and Recycling which looks into the possibility of using Poly-L-Lactic Acid (PLLA) biopolymer to capsulate and safely dose chemicals to human urine.

Alkaline dehydration of urine for recycling of plant essential nutrients requires fresh urine to be stabilized with alkali or metal hydroxides. Improper handling and exposure to these chemicals may cause skin or breathing irritation. Therefore, if these chemicals are wrapped inside capsules made of a biopolymer, human interaction with these chemicals can be minimized and chemicals could be passively dosed to urine. These capsules can also be used for dosing of oxidants and peroxides for the removal of micropollutants and pharmaceuticals from urine.

In the study, degradation of PLLA films in Ca(OH)2 dosed fresh urine was evaluated with temperature, thickness and pH being the variables. The results of this investigation provided some really interesting results in terms of physiochemical changes in the urine and the physical, chemical and molecular changes of the films. If you are interested to find out more and read the full article, click here: .

Approaches for bridging the sanitation delivery gap in urban informal settlements in Namibia

PC: The Namibian

Shack dwellings in informal settlements are home to a billion people worldwide. In Namibia, 40% of the population currently live in shacks. These settlements often lack land tenure and governments do not have capacity to invest in infrastructure in unplanned spaces. Therefore, they are not connected to centralised sewage systems and on-site decentralised sanitation becomes the norm.

In a paper published in the journal City and Environment Interactions, Gert van der Merwe and I explore this grey zone of urban informality and the gap in sanitation delivery in Namibia. We evaluate how local communities, non-government organisations (Clay House Project and Development Workshop Namibia) and an international development agency (GIZ Namibia) interact and navigate the physical, economic and political landscape of implementing bottom-up sanitation solutions for informal settlements. In critical analysis of the three different sanitation delivery models of these organisations, we consider their historical development, underlying philosophies and technical solutions. We also examine how products from different sanitation systems are managed and whether urine source separation could improve their management.