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Who cares about toilets?

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Check out the article we wrote with SLU Global for World Toilet Day.

Today is World Toilet Day. According to WHO and UNICEF around four billion people in the world does not have access to a safely managed sanitation service. Untreated wastewater released to the environment can contaminate drinking-water sources, rivers, beaches and food crops, spreading deadly diseases among the wider population. This is rather unfortunate because source-separated wastewater fractions like human urine and faeces are renewable resources from which water, nutrients and energy can be recovered and safely recycled and used as a fertiliser. So SLU cares!

In the wastewater that comes out of a household, human urine makes up just 1% of total volume. However, in terms of nutrients, urine contains more than 80% of the nitrogen and over half of the potassium and the phosphorus. In fact, urine produced by people worldwide contains enough nutrients to fertilise three-quarters of the food we eat.

Earlier this year, Dr. Prithvi Simha from the Department of Energy and Technology at SLU, defended his thesis, which developed a novel on-site sanitation technology called “alkaline urine dehydration” to capture all the nutrients in urine without its water. Prithvi and his team at SLU are working to disrupt the way we manage wastewater and design sanitation systems. They believe that resources like urine should be separately collected, safely treated to produce fertilisers, and returned to farmland to close the nutrient loop in our food system. If implemented globally, such a system could reduce the transgression of the planetary boundary for nitrogen and phosphorus by 35% and 25%, respectively.

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Talk at the Baltic Sea Science Center in Stockholm

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Last week on 15th of November, Jenna Senecal and Anastasija Vasiljev gave a talk on urine research at the Baltic Sea Science Center in Stockholm. The topic of discussion was “From Fork to Farm and from Farm to Fork. How toilets are a part of this cycle”. The audience consisted of around 20 high school teachers.

Together with another lecture done by Stockholm Vatten och Avfall, we felt that we made quite an impact and we hope that the teachers will feel inspired to share our technologies with their students.

If you want to know more about the Baltic Sea Science Center and what they do, click here.

And to see what SLU is doing regarding the center, click here.

Happy World Toilet Day!

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Today is all about toilets! Can you imagine how your life would be without one? They are a part of our lives so much, that we don’t even think about their existence.

Unfortunately, that is not the case for more than 3.6 billion people. They lack access to safe sanitation and their lives without a toilet are dirty, dangerous and undignified. Public health greatly depends on the toilets, as well as the improvements in gender equality, education, economics, and the environment. Our sustainable future cannot happen without them!

Each of us will spend around a year of their lives using a toilet, so if you have one, thank it and give it some love!

If you want to know more about how we can use toilets to create more sustainable future, please free to check out some of our research:

Happy Wold Toilet Day! 

Studyvisit from Kjell och MĂ€rta Beijers Stiftelse

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Cecilia Lalander from Kretsloppsteknik welcomed visitors from the Kjell and MĂ€rta Beijers Stiftelse at SLU campus in Ultuna. In the spotlight was the latest project “5 ton fish on the counter” (see blogpost from 04. March https://blogg.slu.se/kretsloppsteknik/2021/03/04/red-containers-at-campus/), where feed for trout was produced from insect meal at Campus Ultuna.

The visit was a great opportunity to show the groupÂŽs strong competences and relevance in regards of circular economy (wastemanagement and feed production). After a quick visit, the group hurried on to visit other research groups and get an insight to the wide and important research conducted at SLU.

The Kjell and MĂ€rta Beijer Foundation was founded in 1974 through a donation from Kjell and MĂ€rta Beijer. In addition to scientific research and education, the foundation supports culture, above all in connection with Swedish design and home furnishing tradition. Among other things, the foundation is behind the Beijer Institute, one of the world’s leading research centers in ecological economics. It had been a great day and Cecilia received a lot of interesting questions and also witnessed some of the visitors testing our dried larvae first hand!

Our BSF project “5 ton grön fisk i disk” featured in Dagens nyheter

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From February to May 2021, the project “5 ton grön fisk i disk” (partly financed by Vinnova) produced 1,7 tons of larvae on a mix of 10 tonnes vegetable and bread waste. The vegetables were discarded vegetable cuttings from

Sorunda Grönsakshallen and the bread was out-of-date Fazer bread from local supermarkets. The larv ae were not only produced at SLU campus but they were also further processed here: after drying at 60°C for 48 h, the dry larva were pressed in a screw press to separate the protein from the fat. The defatted protein meal was then turned into fish feed, containing many other locally sourced ingredients, for rainbow trout. The trout were grown by Älvdalslax in Dalarna.

The residue from the treatment, the frass, was used as soil amendment on the nearby student run permaculture garden. Dagens nyheter found out about this cool project and came to visit us. Jessica Ritzen followed Cecilia Lalander and Anders Kiessling through the different stages of the protein production for the 5 ton fish on the counter project. Read the full article here.

New publication from the urine dying group on the use of magnesium-doped alkaline substrates in the Chemical Engineering Journal

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In our latest paper, published in the Chemical Engineering Journal, we show how all the nitrogen in fresh human urine can be captured in the form of solid urine-based fertilisers.

Abstract: Recycling urine can reduce the flux of reactive nitrogen in the environment. This paper presents a novel approach to recover all N (Ntot) from urine, including ammonia (TAN; about 5% of Ntot), which is usually volatilised when alkalised urine is dehydrated. As analytical methods for measuring N have a standard deviation of at least 5%, real fresh urine was fortified with ammonia (urineN) or ammonia and phosphate (urineNP) so that TAN comprised 10% of Ntot. The urine was then added to different magnesium-based alkaline substrates (MgO, Mg(OH)2, MgCl2 + Mg(OH)2) and dried at 38 ˚C. Chemical speciation modelling suggested that, irrespective of the substrate, >98% of Ntot in urineNP was recovered and 86% of TAN was precipitated as struvite. Experimental results showed that < 90% of Ntot was recovered when urineNP was dried in MgO and Mg(OH)2, suggesting that no TAN was captured. However, all phosphorus and potassium and 93% (±5%) of Ntot and 30% of TAN were recovered when urineNP was dried in MgCl2 + Mg(OH)2, as the [Mg]:[NH4]:[PO4] molar ratio of 1.69:1.14:1.0 in urine favoured formation of struvite. Overall, this study demonstrated that all ammonia excreted in real fresh urine (unfortified, TAN < 5% Ntot) can be captured if urine is dried in substrates containing 3.7 g MgCl2·6H2O L−1 or 2.2 g MgSO4 L−1, but no calcium. Ammonia can also be captured if fresh urine is saturated with MgO or Mg(OH)2 with high reactivity (<60 s citric acid test). If the drying substrate has pH > 10 throughout the treatment, urease enzyme-catalysed degradation of urea to ammonia is prevented, resulting in complete recovery of all nutrients. The end-product is a solid fertiliser containing 10–11% nitrogen, 1–2% phosphorus and 2–3% potassium.

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Advertisement for MSc thesis: To source separate or to annamox? Can we mainstream two disruptive innovations in wastewater treatment in parallel?

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Proposed Title: To source separate or to annamox? Can we mainstream two disruptive innovations in wastewater treatment in parallel?

Credits: 30 credits; Level: Advanced
Subject: Technology, Environmental Science or Sustainable Development
Start: January 2022 or later

Two of the most exciting and potentially disruptive innovations that are being tested in the field of wastewater treatment are:

  • Source Separation, where different fractions of household wastewater (urine, faeces/brownwater, greywater) are separately collected at source and treated differently to recover and recycle resources (fertilizers like urea and struvite, water, energy, 
)
  • Annamox, oranaerobic ammonium oxidation, a naturally occurring microbial process which can be applied to remove nitrogen at centralised wastewater treatment plants by directly converting ammonia and nitrite to nitrogen gas.

Source-separation calls for distributed/decentralized treatment of wastewater and emphasizes the recovery of nutrients and resources. Annamox on the other hand calls for an upgrade on the existing biological nitrogen removal processes at centralized wastewater treatment plants. Both these innovations are currently being mainstreamed but little is known about –

  1. Whether these processes can complement each other, and if so, when? at what scale?
  2. In which context and settings are each of these innovations better suited?
  3. The overall energy requirements for treating wastewater through both processes, especially from a life-cycle perspective. e.g., annamox reduces the energy demand for aeration and nitrogen removal but source separation and nutrient recycling reduces the need to manufacture synthetic ammonia-based fertilizers (Haber Bosch nitrogen)
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New Formas project in the call From research to implementation for a sustainable society 2021

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Cecilia Lalander from the Department of Energy and Technology and Anders Kiessling from the Department of Animal Nutrition and Management are part of a project with partners from all over Sweden who have just been granted SEK 3.8 million from FORMAS for a pilot project in which artificial intelligence (AI) will support the development of a sustainable urban food production system.

Northern Sweden has recently attracted large industries and server halls as well as the next generation fossil-free steel industry (H2GreenSteel), due to its easy access to renewable energy and natural resources, as well as a cool climate. Boden municipality aims to be Europe’s most resource-efficient and carbon-neutral municipality by 2025. In fact, since 2020, Boden has initiated a large-scale symbiosis project called the Boden Energy Symbiosis, part of the Boden Business Park. In fact, since 2020 Boden has initiated a large-scale symbiosis project called the Boden Symbiosis Cluster, part of the Boden Business Park. One of the initiatives aim at creating an urban food competence platform of commercial size to be used as a national asset for implementing and testing innovative solutions for food production systems.

Continue reading New Formas project in the call From research to implementation for a sustainable society 2021