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Strategies for a paradigm shift in human excreta management
Fabian Esculier

Coordinator of OCAPI and researcher at Ecole des Ponts ParisTech in the LEESU laboratory

As a higher-level civil servant of the French Ministry of Ecology, he worked for 6 years for various public institutions in the water sector. In 2014, he set up the OCAPI action research program, which aims to study and support the socio-ecological transition of food/excretion systems, and in particular to investigate the potential for a paradigm shift in the management of human urine and feces through source separation and agricultural valorization. He defended his thesis in March 2018 on this topic. He is now the coordinator of a multidisciplinary action research team (biogeochemistry, agronomy, sociology, anthropology, geopolitics, territorial ecology...). The OCAPI program has become a publicly funded national resource centre for source separation.

Zoom Chat

Lighthouse Projects


Low Flush Urine Diversion Vacuum Toilet Applications
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Lotte Kristoferitsch

EOOS NEXT, Austria

EOOS NEXT is an industrial design studio and a social enterprise that strives for positive change by designing transformative technologies currently in the fields of mobility, health, water, self-sufficient toilets and electricity with the aim to drive forward the development of social and sustainable design projects. The multidisciplinary studio is managed by Lotte Kristoferitsch and Harald Gründl.

EOOS NEXT is a Vienna based social enterprise working in WASH since 10+ years. The industrial design studio has developed the passive urine separation technology 'Urine Trap' that has been integrated into various toilet typologies so far. The latest project demonstrates the effluent quality improvements for Biogas processes due to separated urine and anal cleansing water at source, currently field tested at 3 sites in India.

The urine-to-fertilizer system at the PAE Living Building
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Pete Munoz

Nutrient Recovery Services, Oregon, USA

Pete Muñoz is an international lumiére in his innovative work as a licensed engineer, certified wastewater treatment plant operator. He has been involved in over 200 infrastructure projects involving wastewater treatment, stormwater management, rain harvesting, environmental remediation, and watershed restoration. Pete co-founded SEEDS in 1990, a nonprofit organization working at the intersection of the fields of design, education, and ecology. He is a partner in the Alliance for Regeneration, an EcoDistricts Incubator faculty and regularly teaches courses at Yestermorrow Design/Build in Warren, Vermont and the Omega Institute in Rhinebeck, New York. In addition to co-founding NRS in 2021, Pete currently manages the Biohabitats Cascadia Bioregion office in Portland, Oregon and works around the globe helping to connect communities with appropriate inspirational living water infrastructure.

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Pat Lando

Nutrient Recovery Services, Oregon, USA

Pat Lando has been a leader in nature-based solutions for over 30 years and holds many positions in the field of water reuse and resource recovery. Pat is the Executive Director of Recode, a nonprofit organization that creates sustainable and equitable building code and policy solutions for water, sanitation and nutrient recovery systems. Intentionally collaborative, his leadership finds solutions by convening regulators, technical experts, community leaders, legislators and impacted communities. Pat is the co-chair of the National Gold Ribbon Commission for Urine Reuse, and in 2021 he joined the People’s Water Project steering committee to help the coalition draft national water and sanitation related policies.

Presenters Pat Lando and Pete Munoz will discuss the urine process system that is part of the eco-sanitation system in the "PAE Living building" in Portland, Oregon. The presentation will address the project design process, urine processing system, regulatory requirements and product launch. Pat Lando is planning on delivering products to the summit for people to examine and purchase.

Current fate of Nitrogen and Phosphorus Excretions in France

Thomas Starck


Thomas Starck is 3rd-year Phd student in the OCAPI programm in France. His work focuses on nutrient flows at the regional or national scale.

Relying on data from the ~20,000 wastewater treatment plants in France, we present a detailed nutrient mass-balance of the current French sanitation system. Overall, ~50% of excreted phosphorus returns to agricultural soils, and only ~10% of excreted nitrogen. Increasing wastewater treatment plants yield could improve phosphorus recovery ; however such an approach will only marginally improve nitrogen recovery. Paradigm shift such as urine diversion could help bridge this gap.

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Saint-Vincent-De-Paul: Experimenting with Source Separation in a Dense City

Julie Ginesty

Paris et Métropole aménagement, France

Julia Ginesty is the sustainable city officer for the Paris et Métropole aménagement.

Mathilde Sageot

City of Paris, France

Mathilde Sageot is the study manager for the Water and Sanitation Technical Service of the City of Paris.

Saint-Vincent-de-Paul is a future neighbourhood located in the city of Paris, in the 14th arrondissement. This centuries-old site and former hospital is being transformed by Paris et Métropole aménagement into a residential neighbourhood, welcoming many socially inclusive et resilient innovations. One of them is the implementation of the source separation and valorisation of urine at the scale of the area, namely 600 dwellings, schools and gymnasium, shops and workplaces. The pipe network to collect urine and the urine reclycling technology will be operated by the city of Paris. Mathilde Sageot, from the city of Paris water and sanitation departement, and Julie Ginesty, from Paris et Métropole aménagement, will present the main characteristics of this project.

Zoom Chat

Urine Processing & Research Facilities 

Virtual Tours

University of California, Berkeley, USA:
An automated pilot facility to recover nitrogen via ion exchange
Kara Nelson & Ustav Shashvat 

Our research team at U.C. Berkeley has recently completed construction of an automated pilot-scale system to convert fresh urine to fertilizer via ion exchange. The three-step process involves urea hydrolysis, adsorption, and elution. Using the pilot system, we are evaluating the feasibility of automating these processes, as well as the process performance (nitrogen recovery, upconcentration, regenerability of the ion exchange resins), the cost, and the direct and embedded energy and greenhouse gas footprints.

Zoom Chat

Arizona State University, USA:
Urine Diversion and Treatment Facility Tour
Lucas Crane

The Boyer Research Group at Arizona State University has implemented a pilot-scale urine collection system in a multi-story institutional building, including chemical dosing for urinal maintenance and urine stabilization, membrane treatment for nitrogen recovery, and precipitation for phosphorus recovery. Our work draws on key knowledge from stakeholders, such as facilities management, manufacturers, and users, to improve our urine collection and treatment systems. This virtual tour gives an overview of the entire process, from the restroom all the way to the final product.

University of Melbourne, Australia:
Demonstrating nutrient recovery into a liquid fertiliser using a pilot-scale UGold system
Veera Koskue

UGold is a bioelectroconcentration technology designed to recover key nutrients (nitrogen, potassium, and phosphorus) from urine as a concentrated liquid fertiliser. This virtual tour takes you to our pilot scale field demonstration facility, where we are currently trialling the UGold system for nutrient recovery from real source-separated human urine as part of the Nutrients in a Circular Economy (NiCE) research hub ( The pilot system operates next to a public toilet block equipped with Wostman EcoFlush urine-diverting toilets and a Uridan waterless urinal facilitating urine collection separately from other wastewater fractions. The system is designed to treat ca. 40 L of urine per day.

zirkulierBAR research project, Germany:
Showcasing VunaNexus process operated as a container-based urine treatment technology
Carsten Beneker

The German research project zirkulierBAR has integrated the VunaNexus urine treatment technology into their regional circular organizational model. This back-end solution for urine treatment is a milestone on their mission to demonstrate scalable recycling facilities for the treatment of dry toilet contents. In this virtual tour, environmental engineer Carsten Beneker will present to you the container-based urine treatment facility and give you additional glance on the attached faecal matter composting plant. The end-products are non-hazardous, nutrient-rich and low-emission recycling fertilizers for agriculture and horticulture. Bio-economy and municipalities are offered a blueprint for resource-efficient alternatives to sewager-based systems, particularly interesting for rural communities of arid regions as well as facilitators of public toilets (service).

Design & Sociotechnical Dynamics


Ecological sanitation as a social movement a look in the rear-view mirror

Marine Legrand


Rooted in environmental anthropology, her research focuses on the "greening" of landscape planning and city making in post-industrial contexts. Within the OCAPI research program, she works on the emergence of new modes of management of human excreta in France, and the renewal of knowledge, practices, and imaginaries related to ecological sanitation. She is also interested in an art-science approach to body fluids, waste, fermentation, rotting, etc.

In Europe today, the development of alternatives to conventional sanitation brings together a wide variety of players: citizens, associations, companies, start-ups, researchers, local authorities and even some public agencies. In this presentation, we would like to look back at the history of the emergence of ecological sanitation, emphasizing its "social movement" dimension: indeed, since the 1960s, writings have been circulating, techniques have been developed, mobilizations have emerged, positions have been asserted and networks of players have been organized. This raises questions about the contours of this dynamic, and its place within the environmentalist and political ecology movements. Using France as an example, we'll look first at the actors behind the emergence of compost toilets and urine recollection, then at the types of discourse deployed to challenge conventional approaches to sanitation. Finally, we'll ask how looking back on this history can serve as a resource to support the deployment of this movement today to a "critical mass" it has yet to reach.

Technological and Social Dimensions of Urine Diversion Systems in Commercial and Institutional Buildings

Lucas Crane

Arizona State University, Arizona, USA

Lucas Crane is a Doctoral Student in Environmental Engineering in the School of Sustainable Engineering and the Built Environment at Arizona State University, where he is affiliated with the STEPS (Science and Technologies for Phosphorus Sustainability) Center. His current research focuses on advancing the implementation of urine diversion and treatment processes to recover phosphorus. Crane holds a MS in Environmental Engineering from Arizona State University.

Ashton W. Merck

NC State University, North Carolina, USA

Ashton W. Merck is a Postdoctoral Researcher at NC State University and a Scholar at the STEPS (Science and Technologies for Phosphorus Sustainability) Center. Merck is an interdisciplinary social scientist whose research focuses on emerging risks in food and agriculture. Merck holds a PhD in History from Duke University.


Urine diversion (UD) has been shown to provide major benefits for wastewater treatment systems to achieve circular economy goals and can reduce environmental pollution via nutrient separation and recovery. However, there has been limited implementation of UD in the real world, as there are significant technological challenges associated with the current state of UD, such as precipitation within wastewater pipes that leads to clogging and odors. These technological challenges exacerbate negative social perceptions of UD, not only from users but also from implementers of UD, i.e., building managers, maintenance staff, administrators, etc. This presentation details key findings from a convergence research project that addresses both the social and technological challenges associated with implementing UD. In addition to field investigations of a full-scale UD pilot at a multi-story institutional setting on Arizona State University's campus, a benchmarking study was conducted to assess viability of UD in different types of commercial and institutional buildings, and a qualitative research study was conducted to assess stakeholder views and perceptions of the prospects of expanding UD beyond the field trial at ASU. Results from monitoring of the full-scale UD system show the importance of building occupancy and seasonal patterns in urine generation, and that targeted acetic acid dosing schemes can mitigate clogging concerns but allow for suitable phosphorus precipitation after storage. The benchmarking study shows that buildings with higher occupancy counts and/or times, such as office buildings, hospitals, schools, and airports, are most suitable for UD implementation. The qualitative study shows that economic and regulatory/legal factors are major barriers to UD implementation. Social and cultural opposition from existing maintenance staff is also important. These findings suggest that future implementation of UD requires interventions throughout the UD process and relies on engagement from both users and implementers to succeed. Technological interventions must prevent the challenges of current UD systems but should support urine processing methods, as well as align with economic, regulatory, social, and cultural factors of a specific CI building.

Current fate of Nitrogen and Phosphorus Excretions in France

Valentin Aubois-Liogier

CITERES, University of Tours, France

Valentin Aubois-Liogier is a PhD student in Design and Urban planning (CITERES, University of Tours). His doctoral research aims to study users' and stakeholders' experience of ecological sanitation systems, especially urine recycling systems.

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The recycling of human urine requires to address sociocultural aspects involved in the alternative sanitation system. The project Urocyclus aims to design and study in this way this kind of innovation. First experimentation of the dry gender-inclusive urinal designed for the project was carried in March 2023 at the University of Tours in France. Field research was carried at the same time to study users' experience and the acceptance process. The presentation aims to present the results of these experimentation and fieldwork.

Designing for source separation – the key to a regenerative building

John Lansing 

PAE, Oregon, USA

John Lansing is a lead plumbing designer at PAE, a consulting engineering firm in Portland, Oregon. John specializes in applying sustainable solutions to plumbing systems and research on international engineering design guidance. He also serves on the technical committees for the IAPMO Water Efficiency and Sanitation Standard (WEStand) and the ICC 815 Standard for Sizing Water Distribution Sanitary Drainage and Vent Piping Systems.

Source separation of greywater, urine drainage, and feces drainage is a fundamental first step towards regenerative building design and addressing the biochemical flows from buildings that threatens to exceed safe planetary operating limits. We’ll discuss design guidance in this area as well as actual installations in Portland and Seattle and how source separation can be integrated into buildings while minimizing complexity and cost.

Answering the Cautionary "What If?": Applying a Risk Analysis Framework to Determine Safe Use of Urine-derived Fertilizers
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Hayley Joyell Smith

Michigan State University and PHLUSH, USA

Hayley Joyell Smith is recent graduate from University of Georgia where she completed a dissertation on the social-environmental systems and education pathways toward ecological sanitation. She is now a post-doc at in the Biosystems and Agricultural Engineering department at Michigan State University. Smith has also served on the board of PHLUSH (Public Hygiene Lets Us Stay Human) for seven years.

Advocates of urine diversion systems can use a risk assessment framework to help decision-makers understand how implementing a new toilet system or applying a human-derived fertilizer may or may not pose a public health or environmental risk. Quantitative Microbial Risk Assessment (QMRA) is a reputable modeling method that estimates risks under certain circumstances. The risk analysis framework includes: 1. QMRA (hazard identification, dose-response assessment, exposure assessment, and risk characterization); 2. Risk Management; and 3. Risk Communication. QMRA can accommodate varying situations such as length of storage, treatment process, or potential cross-contamination of fecal matter. This presentation will share a case study developed during the QMRA IV Institute (NIH #R25GM135058) that explores the risk of a potential scenario where a child eats soil in a public park that uses urine-derived fertilizer. Results provide evidence that there is a low risk of illness when best practices for risk management are in place. The use of this tool can provide evidence for the safe use of urine-diversion and urine-derived products.

Zoom Chat

Regulatory Pathways

Roundtable Discussion

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Kai Udert

Swiss Federal Institute of Aquatic Science and Technology (Eawag)

Kai Udert is with the Engineering Department at EAWAG and has been working on nutrient recovery from urine for most of his career. His research is guided by the principles that human waste must be seen as a resource to replenish nutrients for food production and to prevent environmental pollution due to uncontrolled discharge.

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Pat Lando

Recode, Oregon, USA

Pat Lando has been a leader in nature-based solutions for over 30 years and holds many positions in the field of water reuse and resource recovery. Pat is the Executive Director of Recode, a nonprofit organization that creates sustainable and equitable building code and policy solutions for water, sanitation and nutrient recovery systems. Intentionally collaborative, his leadership finds solutions by convening regulators, technical experts, community leaders, legislators and impacted communities. Pat is the co-chair of the National Gold Ribbon Commission for Urine Reuse, and in 2021 he joined the People’s Water Project steering committee to help the coalition draft national water and sanitation related policies.


Mathew Lippincott 

University of Michigan, MI, USA

Mathew Lippincott is a technical writer who has worked on reform of building mechanical codes since 2010. Mathew led writing of the IAPMO/ANSI WE Stand chapter on composting and urine diverting toilets, and is currently working with the University of Michigan's Food, Ecology & Equity: Designing Circular Nutrition Production (FEED CNP) program on regulatory pathways for urine diversion in Michigan.

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Aleksandra Jaeschke

University of Texas, Austin, USA

Aleksandra Jaeschke is an architect and an Assistant Professor of Architecture at The University of Texas at Austin. Born and raised in Poland, she holds a Doctor of Design degree from the Harvard GSD and an AA Diploma from the Architectural Association in London.


John Lansing 

PAE Consulting Engineers, Oregon, USA

John Lansing is a lead plumbing designer at PAE, a consulting engineering firm in Portland, Oregon. John specializes in applying sustainable solutions to plumbing systems and research on international engineering design guidance. He also serves on the technical committees for the IAPMO Water Efficiency and Sanitation Standard (WEStand) and the ICC 815 Standard for Sizing Water Distribution Sanitary Drainage and Vent Piping Systems.

Zoom Chat


Urine Processing Startups

Sanitation360 - Urine Processing as a Business
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Jenna Senecal

Sanitation360, Sweden

Jenna is a Bioresource engineer and completed her PhD at the Swedish University of Agricultural Sciences, where she co-developed a urine stabilizing and drying technique. Jenna is now leading the commercialization of the technology through Sanitation360.

Previously we presented about how we make and use the urine fertilizer. This year we will present on how we got the company starting and how we are currently financing the fertilizer production and where we are aiming to be in 5 years. We are still pre-commercial and dependent on soft funds to operate. We will share the business model, target markets, and pilot projects that we have running.

Urine nitrification in Switzerland and Europe, updates from VunaNexus
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Nadège de Chambrier

VunaNexus, Switzerland

Nadege is an Environmental Engineer from ETH Zurich. After different projects in decentralised sanitation during her master, she worked on a project to develop a mobile urine treatment plant at Vuna. She co-founded VunaNexus summer 2022. She is now responsible for the technology development and projects management.

After many years of development and optimisation in the swiss water research institute Eawag, the urine nitrification technology, often called Vuna-Technology is now being further industrialised and sold by the company VunaNexus. In this presentation, you will understand how the technology works, what its products are and hear updates about the latest advancements.

Brightwater Tools: Building the Business Case for Source-Separation

Abe Noe-Hays

Brightwater Tools, Vermont, USA

Abraham Noe-Hays has been working with dry sanitation systems since 1990. He holds a B.A. in Human Ecology with concentrations in agroecology and compost science from the College of the Atlantic, where his interest in recycling human manure was solidified by an internship at Woods End Research Laboratory and a thesis project, “An Experiment in Thermophilic Composting.” He has operated Full Circle Compost Consulting since 2001, providing complete design, manufacture, and maintenance services to individuals and institutions with dry toilet systems. He is now the Chief Technology Officer (CTO) of Rich Earth’s spin-off, Brightwater Tools.


Kim Nace

Brightwater Tools, Vermont, USA

Kim Nace holds an M.A. in International Administration from World Learning and an M.A. in Educational Leadership from Keene State College. She was a Peace Corps volunteer in Botswana and has taught children of all ages. She coordinated research funded by the MacArthur Foundation and later served as an Elementary School Principal – in rural Vermont and in Chennai, India. She has been passionate about sustainable sanitation alternatives ever since creating an educational video about composting toilets for her 1989 master’s thesis project. As Co-Founder and Executive Director of the Rich Earth Institute, she focused her leadership and organizational strengths to build a high performance team at the Institute and to engage others in the possibilities and practicalities of urine recycling. Kim is now CEO of Rich Earth’s spin-off organization, Brightwater Tools. Kim and her family use a urine diverting composting toilet.

For building developers to adopt nutrient recovery and water reuse strategies in a widespread way, they must see a financial benefit. Brightwater Tools, Inc., an NSF-funded spinoff of the Rich Earth Institute, is dedicated to developing and supplying equipment for processing source-separated wastewater, which will enable buildings of the future to cost-effectively employ onsite resource-recovering wastewater treatment. In this presentation, we will discuss our observations of the business climate surrounding the adoption of these new technologies and present our vision of a cooperative, collaborative future.

Unleash the power of urine to produce microbial biofertilizers: Experience from France and Belgium  

Julien Saludas

Toopi Organics, France

Julien Saludas, Chief Development and Impact Officer of Toopi Organics. Agronomist with 15 years of experience in farmer co-op and agroinput companies in France.

Zoom Chat

Two-Part Panel

Urine Fertilizer in Agriculture

Part 1

Application of Urine-Derived Fertilizers for Ecological Nutrient Management

Lucinda Li

University of Michigan, Michigan, USA

Lucinda Li is a graduate student at the University of Michigan in the Department of Civil and Environmental Engineering.

Urine-derived fertilizers (UDFs) have chemical characteristics that more closely resemble those of inorganic fertilizers than of other waste-derived fertilizers. Similar to inorganic fertilizers, UDFs may lead to substantial nitrogen (N) losses through leachate and N 2 O emissions. To harness the full potential of UDFs for environmental benefits, an ecological nutrient management (ENM) approach is needed. ENM leverages ecological insights into soil nutrient cycling to achieve optimal plant growth while simultaneously preserving long-term soil functionality and mitigating nutrient losses. One key ENM strategy involves the synergistic use of soluble fertilizers, such as inorganic fertilizers and UDFs, alongside organic amendments. A better understanding of N loss magnitude and pathways from using UDFs alone and with organic amendments can inform improved uses of UDFs. We conducted a greenhouse experiment to compare the impacts of a UDF to an inorganic and organic fertilizer on soil health and N cycling. The experiment revealed that the UDF increased plant yield by a comparable amount to the inorganic fertilizer with no compromise to soil health. Due to their similarities in N availability, the effects on soil N cycling were more similar between UDF and inorganic fertilizer than to the organic fertilizer. When compost was applied with UDF, there were higher N 2 O emissions per gram of plant available N applied, but the ratio of N loss (as leachate and N 2 O emissions) to N harvested significantly decreased. The similar behavior of the UDF and inorganic fertilizer suggests that UDFs can substitute inorganic fertilizers, significantly reducing resource consumption in agriculture. Additionally, there is an opportunity for UDFs to contribute to ENM goals by combining their application with organic fertilizers.

Grow-as-You-Go: Container-based sanitation meets container-based gardening

Rebecca Nelson

Cornell University, New York, USA

Rebecca Nelson is a Professor at the Cornell University College of Agriculture and Life Sciences. Rebecca Nelson's interests focus on sustainable agriculture and food systems, with research activities and engagement in Africa, India and New York. Her research group has four main focus areas: the circular bionutrient economy (CBE); mycotoxin management; disease resistance in crops (particularly maize); and agroecology and food systems.

Urban and peri-urban soils are often contaminated with heavy metals and other pollutants that render them unsafe for food production. To develop safe, cost-effective, and sustainable options for raised bed gardening in these contexts, we are exploring an idea we call "Grow as You Go" or YouGo gardening -- the proposition that crops can be grown on soilless media based on organic underutilized resources (OURs, such as high-carbon agricultural residues), conditioned and fertilized with urine. In initial exploratory gardens conducted over three seasons, we were able to produce a range of vegetables on straw bales and in sacks of cereal residues and various amendments using urine as a conditioner and fertilizer. In 2023, we conducted a series of experiments in the US and Kenya using various carbon sources (wheat straw, corn stover and rice husks) and amendments (compost and biochar to favor a beneficial microbial community; FeSO4 and wood vinegar to reduce pH). Specific experiments were conducted to investigate issues related to substrate composition, decomposition and particle size distribution; water retention; salt accumulation; and the effects of biochar on plant production. Urine fertilization of kale grown on maize stover (with or without biochar) produced yields that were not statistically different from the corresponding yields obtained using synthetic fertilizer. In contrast, the yields obtained with urine fertilization were lower than with synthetic fertilizer on both soil (in sacks) and wheat straw substrates (in bales). In an experiment aimed at understanding salt buildup across substrates under urine fertigation, two-fold differences in water application did not influence yield across substrates; further analysis is being conducted with greater differences in flush rates. The effect of biochar varied across experiments. Yields of tomato and kale were not influenced by the presence of biochar in the medium in two experiments. In another experiment, however, okra plants did not survive on maize stover fertilized with urine, did poorly on maize stover irrigated with water, and grew well with urine + biochar. We found that okra growth was not substantially influenced by the size distribution of maize stover substrate, indicating that shredding the stover may not be necessary subsequent to coarse chopping.

Simulating reverse blending of dehydrated human urine fertilisers with organic wastes to meet macronutrient demand of 15 major food crops

Fernando Perez

Universidad Mayor de San Simon, Bolivia

Fernando Perez has a PhD in technologies for waste treatment and reuse at the Swedish University of Agricultural Sciences (SLU). He is a researcher at the University of San Simon in Bolivia. Collaborating with the group of environmental engineering from SLU in developing the drying technology for treatment and reuse of urine.

This study evaluated the suitability of blending different organic wastes with dehydrated alkalized human urine to produce urine-based fertilizer blends that meet macronutrient requirements of major food crops. Using a modelling approach known as reverse blending, we developed blends comprising of dehydrated urine and organic waste(s), estimated their elemental composition, and simulated their potential to meet nitrogen, phosphorus and potassium (macronutrients) demand of 15 crops. The modelling was done using data on concentration of macronutrients in organic wastes and dehydrated urine, as well as macronutrients requirements of crops that was systematically sourced from peer-reviewed literature. Overall, we identified 388 organic wastes and simulated them with dehydrated urine to identify 38 blends that fulfilled the nutrient requirements of the 15 major crops. We found most of the identified blends contained ash and biochar, as the low N content and high P or K content of these organic wastes were found to balance the high N but low P and K content of dehydrated urine. We also identified four blends that met the nutrient demand of at least three crops. The simulated blends contained 5-17% N, 1.8-10% P and 2.5-20% K, and are therefore similar in composition to commercial mineral fertilizers. Overall, we conclude that organic wastes with high content of one of the macronutrients (N, P or K) are most suitable for blending with dehydrated urine and that it is possible to tailor urine-based fertiliser blends that better match nutrient requirements of different crops.

Zoom Chat

Part 2

Urino-fertilization of lettuces day after day
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Renaud de Looze

Palmeraie des Alpes, France

Engineer, nurseryman and experimenter author of the book, instructions for use, "L'urine de l'or liquide au jardin", translated into German and Spanish.

Anthroponics: Closed Loop Hydroponics
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Dan Hettinger

Living Web Farms, North Carolina, USA

Out of his small shop and gardens in Weaverville NC, Dan develops appropriate technology for creating value from waste streams and maximizing small farm efficiency. Dan is a biochar specialist; an experienced educator, professional fabricator, hobby farmer, handyman and amateur artist.

Introducing 'Anthroponics' as a very efficient and truly circular method of hydroponic growing with urine as a primary nutrient source. I'll include my trials with nutrient balancing, biochar-based grow media and nitrification media, duckweed, and lettuce and Japanese indigo production in my 500 gallon experimental system.

Reducing On-Farm Ammonia Loss From Manure through Fermentation Using Whey & Paper Fibers

Abe Noe-Hays

Rich Earth Institute, Vermont, USA

Abe is the Research Director of the Rich Earth Institute, where he coordinates a multidisciplinary research and demonstration effort involving farmers, scientists, planners, and volunteer participants, with the goal of developing tools and methods to allow other communities to start recycling urine. A lifelong resident of Vermont, he has used alternative sanitation systems since 1976, and has been academically and professionally involved in their development since 2000.

Ammonia volatilization from manure is a major source of nitrogen pollution in the environment, and also reduces the fertilizer value of manure or source-separated urine on the farm. Conventional methods of acidification have shown promise in mitigating ammonia emissions but involve the use of concentrated inorganic acids, which can be hazardous and expensive to handle. The Rich Earth Institute researched an innovative approach to reducing ammonia emissions: Bio-Acidification via Fermentation. This method introduces carbon-rich waste materials into liquid manures, initiating a fermentation process that generates organic acids. This, in turn, lowers manure pH and mitigates ammonia loss. During this webinar, we will share our research findings fermenting liquid dairy manure, digestate, and pasteurized human urine, collected through our Urine Nutrient Reclamation Program.

Zoom Chat


Portable Toilets

Kompotoi: We Make the Best out of Your Shit!

Jojo Casanova-Linder

Kompotoi, Switzerland

Jojo Casanova-Linder is the co-founder of Kompotoi, Switzerland. Jojo Linder was a Project Manager and Event Organizer has organized sports events himself. Through studying permaculture he became aware of compost toilets and wanted a better solution for the event industry.

Unlocking Nutrient, Energy, and Water Recovery Potential, Minimizing Emissions, and Exploring Water Circular Practice

Benson Colella

Wasted*, Vermont, USA

Benson holds a M.S. and B.S. in Chemical Engineering from Worcester Polytechnic Institute. Benson was introduced to urine-diversion as an intern of the Rich Earth Institute in 2019, where he worked on the development of a urine freeze-concentrator among other assignments. He is excited to continue the work of reclaiming resources from human "waste" as an engineer at Wasted* in Burlington, VT. Benson takes pleasure in making use of discarded or overlooked resources; and he enjoys foraging, canning and brewing, dumpster diving, and tinkering.

Portable toilets, a common fixture in our daily lives, have long been overlooked in academic literature, particularly concerning decentralized waste management and the potential for circularity and resource recovery. This presentation shares insights from an extensive study characterizing portable toilet waste, revealing its unique composition and multifaceted environmental implications. In addition to exploring the chemical makeup of this waste, our research delves into the often untapped potential for nutrient, energy, and water recovery, aligning with principles of sustainable resource management and circular economy. Identifying valuable nutrients within the waste stream offers opportunities for recycling, repurposing, and mitigation, with the aim of reducing the environmental footprint. Furthermore, we investigate organic matter and methane emissions associated with portable toilet waste, recognizing their significance as potential greenhouse gases and renewable energy. A comprehensive understanding of these emissions informs both waste management practices and sustainability efforts. In conclusion, our research provides a holistic perspective on portable toilet waste, highlighting opportunities for sustainable resource utilization, considerations for circular practices, and the importance of minimizing emissions due to storage, transport and treatment. This presentation invites discussion on innovative waste management solutions and underscores the broader implications for sustainable practices across diverse settings.

Rich Earth Institute Nutrient Reclamation Portable Toilets: A Gateway to Circular Sanitation
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Arthur Davis

Rich Earth Institute, Vermont, USA

Arthur Davis holds a B.A. in Geology and Environmental Studies from Oberlin College and has been working with alternative sanitation systems since 2013. This includes working on the Living Machine Wastewater System at Oberlin College and work as a marine engineer on an educational tall ship in the Puget Sound region. He is excited to be back home in Brattleboro, VT, working toward completing the food nutrient cycle. At Rich Earth, Arthur directs Rich Earth’s community-scale urine recycling program (the Urine Nutrient Reclamation Program), coordinates the portable toilet service, and works on technical and agricultural research projects. He also works as an R&D engineer at Rich Earth’s spinoff company Brightwater Tools.

Zoom Chat

Two-Part Panel

Urine Treatment and Processing Research 

Part 1

Fate of antibiotic resistance genes and their carriers through preparation of struvite from source separated urine
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Nebiyat Nigusie Woldeyohannis

Addis Ababa University, Ethopia

Nebiyat is a PhD student at Addis Ababa University in Prof Adey's laboratory since 2016.

Struvite is an ecofriendly fertilizer especially when it is derived from human urine since this approach addresses sanitation issue too. In our study using sequencing of microbial genomes and using bio-informatics tools, we found different antibiotic resistance genes and their carriers in both stored urine and struvite. We found in struvite even after urine sanitization the resistance to aminoglycosides, carbapenem, chloramphenicol and erythromycin and efflux pump, with top carrying pathogens including Acinetobacter, Aeromonas and Enterococcus. The identified families of the antibiotics were shown persistent in struvite with a shift in gene families. On the other hand, metagenome-derived genome sequence analysis revealed the dominance of phages of Streptococcus, Bacillus and Escherichia in struvite. This indicates the abundance of carriers, the phages to antibiotic resistance genes. In addition, in our study plasmid sequences were spotted in genomic sequences using machine learning tool. Among the spotted plasmids most of them were blasted on NCBI and found to carry antibiotic resistance genes including the last resort antibiotics. The detection of the resistance-gene-carriers (mobilomes) in the struvite sample requires due attention before implementation of struvite in agriculture. Further standardization of the struvite production process with regard to minimization of resistance gene carriers is recommended.

Urine to High Value Compost: A Viable Model?
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John Culpepper

Compost for Good, New York, USA

John Culpepper co-founded Compost for Good to help communities around the world to upcycle all appropriate organic materials to: reduce greenhouse gas emissions; keep resources in local communities; create business opportunities; help solve water quality issues; and lower the cost of food and fiber production. John has worked in education, facilities management, and research.

Compost for Good received funding to establish a small Human Urine Research and Demonstration (HURD) facility in Upstate NY to try and show the economic viability of processing diverted human urine through a high temperature composting regimen. We will show the results of a variety of experiments in which we’ve produced a high value, biologically robust compost that meets or exceeds the EPA Class A biosolids standards. We will discuss creating recipes using only urine, sawdust, and water, and recipes incorporating food scraps, and how our urine/sawdust recipe can enhance the composting of food wastes. We will discuss/show our Penn State physical analysis along with our analysis of the soil microbes.

Observations from one year demonstration of urine collection and nutrient recovery at a highway rest area

Harold Leverenz

UC Davis / Biohabitats / AEM, California, USA

Harold Leverenz is a research engineer at UC Davis and wastewater process engineer with Biohabitats. Harold co-founded Advanced Environmental Methods LLC (AEM) in 2015 to support the implementation of nutrient recovery projects. Harold is a registered civil engineer in California.

A one year study was conducted at a highway rest area in California along I-5. Urine from waterless urinals was diverted into a collection system and pumped to a nutrient recovery site. At the nutrient recovery site, urine was stored in above ground tanks to allow for hydrolysis. Urine was processed weekly using a coupled steam distillation and struvite process. It was found that the chemistry of the struvite could be modulated based on the operation of the steam distillation process. Struvite was produced with variable fractions of ammonium, potassium, and sodium. Some implications for energy efficiency, overall nutrient recovery, and system operations will be discussed.

Nutrient recovery from urine using the UGold technology: Upscaling from laboratory to pilot scale
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Veera Koskue

University of Melbourne, Australia

Dr Veera Koskue works as a Postdoctoral Research Fellow at the Department of Chemical Engineering, University of Melbourne, Australia. She has several years of research experience on nutrient recovery from different wastewater fractions using bioelectrochemical and electrochemical methods. She is currently involved in the interdisciplinary Nutrients in a Circular Economy research hub, funded by the Australian Research Council and industry partners.

UGold is a bioelectroconcentration technology designed to recover key nutrients (nitrogen, potassium, and phosphorus) from urine as a concentrated liquid fertiliser. It is an electrochemical system where the anodic oxidation reactions are catalysed by bacteria that are able to convert the chemical energy in urine to electrical energy. The electricity generated by the bacteria is used to drive the migration of the nutrients (all present in urine in their ionic forms) through ion-exchange membranes into a separate recovery chamber. The system only consumes electrical energy, requiring a small electricity input in addition to the electricity generated by the bacteria; no chemical additions are needed. The UGold technology has been studied extensively with synthetic and real human urine in laboratory scale. Based on the laboratory experience, we are currently trialling the system in pilot scale as part of the Nutrients in a Circular Economy (NiCE) research hub ( In this presentation, we are going to present solutions to technical and operational bottlenecks identified in earlier laboratory work and how these solutions have been incorporated in the pilot system design and operation.

Long-term electrochemical nitrogen recovery for flexible product recovery from urine
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Meili Gong

Stanford University, California, USA

Meili Gong is a research assistant in the Tarpeh Lab of Stanford University. She graduated from the University of Minnesota with a Bachelors of Bioproducts and Biosystems Engineering. She is passionate about resource recovery, sustainable agriculture, and water quality engineering. She’s looking forward to discussing emerging technologies!

The selective recovery of nitrogen from urine can reduce the costs and environmental impacts of municipal wastewater treatment and produce valuable chemical feedstocks for the global fertilizer economy. Electrochemical methods of nitrogen recovery can achieve high selectivity and generate high-purity products, leveraging the high concentration of nitrogen and overall high conductivity of urine. Our group has studied electrochemical stripping (ECS) for recovering nitrogen from urine, focusing on the robustness of this technology for realistic operation and for the recovery of multiple chemical species. These operational factors include the long-term, continuous recovery of nitrogen from urine, as well as urine at varying flush water volumes, divalent cation concentrations, and extents of urea hydrolysis. Experiments were also conducted to characterize the recovery of ammonium hydroxide in addition to ammonium sulfate. We demonstrated successful long-term and continuous processing of urine for 35 days. We observed higher nitrogen recovery via ECS with higher extent of urea hydrolysis, lower divalent cation concentration, and lower urine flush volumes. These results suggest urine collection procedures such as using ultra low flush toilets and storing urine to allow complete hydrolysis of urea can optimize the performance of ECS units downstream. These findings advance our understanding of ECS technologies as at-scale resource recovery units in both centralized and decentralized wastewater treatment.

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Part 2

Phosphorus recovery from source-separated human urine as vivianite
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Chibambila Simbeye

University of Cape Town, South Africa

Chibambila Simbeye is a Civil Engineering Masters candidate at the University of Cape Town. He is passionate about sustainable infrastructure and technology that ameliorates the human living experience while supporting circular economies. The insights he presents today stem from his dedicated work as part of his Master's research project.

Urine contributes over 50% of the phosphorus load in domestic wastewater. Decentralized sanitation systems and source separation provide an opportunity to recover this phosphorus. The present study evaluated the viability of phosphorus recovery in the form of vivianite from human urine, leveraging a combination of thermodynamically modelled and empirically derived data. Our findings reveal that the type of iron(II) salt and reaction temperature exerted no discernible influence on the yield and purity of vivianite. However, the pH of the urine impacted the solubility of both vivianite and accompanying co-precipitates. The highest yield (93 ± 2%) and purity (79 ± 3%) of vivianite were attained at a pH of 6.0. Optimal vivianite yield and purity materialized when the Fe:P molar ratio was greater than 1.5:1, but less than 2.2:1. This specific molar ratio facilitated enough iron to react with all the available phosphorus, concurrently providing a competitive effect that prevented the formation of co-precipitates. Vivianite produced from real urine was less pure (63 ± 5%) than vivianite produced from synthetic urine (95 ± 2%) because of the presence of organics in real urine. These organics can form complexes with the iron and can also attach to the growth points of the vivianite crystal, thus limiting the purity of the vivianite. However, washing the solids with deionized water improved the purity by 15.5%, at a pH of 6.0. Overall, this novel work adds to the growing body of literature on resource recovery (phosphorus) from source-separated urine.

Microbial community analysis of a membrane bioreactor incorporated with biofilm carriers and activated carbon for urine nitrification
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Weonjung Sohn

University of Technology Sydney, Australia

Weonjung Sohn is currently a PhD candidate at University of Technology Sydney under Prof. Hokyong Shon’s supervision. Her main research interests include biological nitrification process in membrane bioreactors for nutrients recovery in a circular economy from source separated urine.

The integration of powdered activated carbon (PAC) and biofilm carriers within a membrane bioreactor (MBR) presents a promising and innovative approach to address the challenge of long hydraulic retention time (HRT) for nitrification of source-separated urine. This study investigated the effect of biofilm carriers and PAC incorporation on microbial dynamics, focusing on dominant nitrifying genera in both suspended and attached growth forms. Our findings indicate that the transition to urine feeding reduced in microbial diversity and richness, a trend further influenced by the addition of PAC and biofilm carriers, likely due to the selective enrichment of specific species. Furthermore, significant shifts in microbial compositions were observed in both MBRs and across different sludge growth forms. Remarkably, the NOB genus Nitrospira was highly enriched in the suspended sludge, while AOB genus Nitrosococcaceae thrived predominantly in the attached biomass, showing a significant 7-fold increase in relative abundance compared to its suspended counterpart. Consequently, the incorporated MBR displayed a 36% higher nitrification rate and 40% reduced HRT compared to the conventional MBR. These findings provide valuable insights for the development of compact and efficient MBR systems tailored for source-separated urine treatment, contributing to the achievements of a circular economy in nutrients.

Photoinactivation of jack bean (Canavalia ensiformis) urease in source-separated fresh human urine
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Natnael Demissie

Swedish University of Agricultural Sciences, Sweden, and Addis Ababa University Institute of Biotechnology, Ethiopia

Demissie is a member of the Swedish University of Agricultural Sciences and Addis Ababa University Institute of Biotechnology.

In source-separating sanitation systems, inhibiting urease activity prevents enzymatic urea hydrolysis and volatilisation of ammonia when urine is concentrated by evaporation. This study tested UV-based photoinactivation as a novel alternative to existing methods of inactivating urease that require dosing urine with acid, base or oxidants. The enzymatic activity of jack bean (Canavalia ensiformis) urease in water, synthetic fresh urine and real fresh urine was investigated, with and without using a low-pressure UV lamp that emitted 185 nm and 254 nm radiation. In UV-free controls, urea was hydrolysed at a rate of 3.2 × 10 -3 mmol mg urease -1 min -1 , 3.3 × 10 -3 mmol mg urease -1 min -1 and 2.0 × 10 -3 mmol mg urease -1 min -1 in water, synthetic urine and real urine, respectively. In the presence of UV, no urease activity was detected in any matrix. A UV dose of 35 J m -2 and 85 J m -2 was needed for inactivating urease in water and synthetic urine, respectively, whereas a UV dose of 1935 J m -2 was needed for inactivating urease in real urine. Photolysis and photo-oxidation of amino acid residues at the active site of the enzyme were likely reasons for inactivation. Organic metabolites in real urine affected photoinactivation by (i) absorbing radiation between 190 nm and 400 nm, which reduced incident radiant flux; and (ii) scavenging hydroxyl radicals, which impeded oxidative damage to the enzyme. Overall, the findings demonstrate the feasibility of on-site treatment using a low-pressure UV lamp for inactivating urease in freshly excreted urine.

Freezing your pee for maximum water removal

Caitlin Courtney

Future Water Institute, Chemical Engineering Department, University of Cape Town, South Africa

Caitlin is an avid Pee-cycler and recent PhD graduate from the University of Cape Town. Her research focuses on nutrient recovery from wastewater, non-sewered sanitation, and membrane technologies.

Urine is a more sustainable alternative to synthetic fertilizers, but, the nutrients need to be concentrated to make the transportation of the fertilizer to agricultural areas economically feasible. Reverse osmosis (RO) is a commercially scalable method that can concentrate urine. However, water removal is limited to 60-70% due to operating pressure limitations and membrane scaling. Freeze crystallization (FC) is also an effective concentration method but is more energy intensive (17 kWh/kg-N recovered, 70% water removal) than RO (2.8 kWh/kg-N recovered). A novel hybrid eutectic freeze crystallization (EFC) and RO system was investigated to improve water removal and energy use. EFC is an extension of FC where salts and ice crystallize simultaneously, the ice and salt can then be separated by gravity. This could be advantageous to crystallize the undesirable salts in urine and improve the fertilizer quality. However, urine is a complex solution, and it was unclear if salts would form simultaneously with ice crystals at the eutectic point. For the first time, it was shown experimentally that Na2SO4∙10H2O crystallizes simultaneously with ice in both real and synthetic urine, thus providing a new method to concentrate human urine for liquid fertilizer production. A theoretical mass balance showed that that 77% of the urea and 96% of the potassium could be recovered. In addition, 25% of the sodium and 87% of the sulfate ions would be remove at a total water removal of 95%. The final liquid fertilizer would have a weight composition of 11.5% N and 3.5% K. A hybrid RO-EFC process would require 10.8 kWh/kg-N recovered (95% water removal), which is substantially less than other concentration methods.

Magnesium air fuel cell for concurrent energy production and phosphorus recovery

Dr. Praveena Gangadharan

Indian Institute of Technology Palakkad, India

Dr. Praveena Gangadharan is an Assistant Professor in the Department of Civil Engineering at the Indian Institute of Technology, Palakkad, India. She is a recipient of Early Career Research Award (SERB, India; 2019- 2022), Women Scientist Fellowship (DST, India; 2014-2017), Bhagyalakshmi Krishna Ayengar Award (IIT Madras; 2017), and Gandhian Young Technological Innovation Award (2015). Her research interests include bioelectrochemical systems for wastewater treatment, desalination, defluoridation of groundwater, nutrient recovery from urine, metal reduction and recovery and electrochemical water or wastewater treatment. She has authored 6 research papers in reputed international journals and 1 book chapter.

A magnesium air fuel cell (MAFC) was fabricated and employed to produce energy and recover nutrients from source separated urine. The MAFCs are fabricated in three different configurations as: (i) single cell MAFC (250 ml), (ii) single cell MAFC (100 ML), and (iii) four chamber modular units. Each MAFCs comprise magnesium anode and a fabricated porous air cathode encompassing three layers (gas diffusion layer, current collecting layer and catalyst layer). The wettability of the air cathode revealed the presence of triple phase interface layer, ideal for oxygen reduction reaction. Each single MAFC cell exhibits a cell voltage of around 1.4 - 1.5 V. The MAFC was able to power LEDs with a power rating of 10 mW to 10 W consistently to power electronic gadgets ranging from LEDs to mobile phones. Along with harnessing energy, nutrient recovery experiments were also conducted in both batch and continuous mode. Optimum operational parameters such as pH, hydraulic retention time, chemical composition of source separated urine were determined. A nutrient recovery efficiency of 99% and 94% was achieved in batch and continuous mode respectively. The recovered precipitate was characterised by XRD, FT-IR, and FESEM-EDS. Thus, MAFC would contribute to the production of clean energy, sustainable waste systems, and circular bio-economy.

Electrochemical ammonia stripping from source-separated urine: cathode-fed operation vs. anode-fed operation

Sudeep Popat

Clemson University, South Carolina, USA

Dr. Sudeep Popat is an Associate Professor in the Department of Environmental Engineering and Earth Sciences at Clemson University. His research group focuses on biological and electrochemical technologies for resource recovery from domestic and industrial wastewater. Some of Dr. Popat's groups recent work includes using electrochemical technologies to enable N and P recovery from source-separated urine, developing electrocoagulation as a possible technology for primary treatment of animal processing wastewater, and expanding the understanding of anaerobic conversion of fats for anaerobic co-digestion applciations for enhanced biogas recovery from municipal wastewater solids.

Electrochemical ammonia stripping from source-separated urine represents an approach through which renewable electricity can power the production of a base at the cathode of an electrochemical cell to result in the volatilization of ammonium in hydrolyzed urine and subsequent recovery of N as ammonia. Typically, such electrochemical systems for N removal/recovery have been designed to operate via anode-fed operation in which a cation exchange membrane selectively transfers ammonium in hydrolyzed urine to the cathode, where it is volatilized and collected as ammonia using gas-permeable membranes. We investigated whether anode-fed operation results in significant chlorine production in urine and if this subsequently leads to the formation of disinfection by-products (DBPs). While such systems leverage the anodic oxidation of water, chloride in urine can also be oxidized to chlorine on most typical anode electrodes. We also investigated if hydrolyzed urine is fed to the cathode of electrochemical cells, then issues related to chlorine production and the formation of DBPs can be avoided. We will present our results comparing anode-fed vs. cathode-fed operation and discuss performance both with respect to rates and efficiency of N removal/recovery.

Electrochemical ammonia stripping from source-separated urine: cathode-fed operation vs. anode-fed operation
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Jiaxi Jiang

University of Technology Sydney, Australia

Dr Jiaxi (Jade) Jiang is a Postdoctoral Research Associate at the School of Civil and Environmental Engineering, Faculty of Engineering and Information Technology (FEIT) at UTS. Currently, she is working at the ARC Research Hub for Nutrients in a Circular Economy (ARC NiCE Hub), utilizing UF-based membrane bioreactor (MBR) technology to achieve complete nutrient recovery and develop next-generation fertilizer from source-separated urine, contributing to sustainability and the circular economy.

Human urine is rich in nutrients and an important source of fertilisers, especially when source-separated urine is available. Due to the increasing focus on the need for nutrient removal and recovery, various technologies and processes are being investigated. This study investigated a hybrid membrane bioreactor (MBR) and membrane capacitive deionisation (MCDI) where the source-separated urine was treated in MBR, and the subsequent MBR permeate was used as a feed for the MCDI for further nutrient removal and recovery. Overall, nitrate, phosphate and ammonium removal were 66%, 49% and 58%, respectively, in the treated urine using MCDI. Additionally, the recovery rate of nitrate, phosphate and ammonium were 80%, 64% and 76% in the concentrated brine. The energy demand for recovery of NH4+ was between 3.03-11.25 kWh/kg of NH4+-N and between 3.87-14.75 kWh/kg of NO3--N for the three different voltages used in the study. The study further demonstrates the viability of MCDI application for nutrient recovery and concentration, effectively using both the adsorption and desorption phases of MCDI operation without using any chemicals.

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Golden Funnel Award

Tove Larsen!


Every year, the Rich Earth Institute recognizes people who have made significant contributions to the field of urine nutrient reclamation. 

This year, Rich Earth Co-founders Abe Noe-Hays and Kim Nace presented the Golden Funnel Award to Dr. Tove Larsen. Dr. Larsen's work has been instrumental in driving the field of urine diversion. Rich Earth and many of our colleagues owe a huge debt of gratitude for Dr. Larsen. Thank you! 

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