Our latest publication on source-seperating wastewater systems in Sweden




Legitimacy of source-separating wastewater systems with Swedish water utilities

Jennifer R. McConvillea, Elisabeth Kvarnströmb, Abdulhamid Aliahmada & Maria Lennartssonc

a Department of Energy and Technology, Swedish University of Agricultural Sciences, Uppsala, Sweden; jennifer.mcconville@slu.se, Abdulhamid.aliahmad@slu.se

b Ecoloop, Stockholm Sweden; elisabeth.kvarnstrom@ecoloop.se

c Research and Development Coordinator, City of Stockholm, Stockholm, Sweden; maria.lennartsson@extern.stockholm.se

Source separation of excreta from the rest of urban wastewater flows can enable safe and efficient nutrient recovery. Yet, source-separating wastewater systems are not yet common in urban areas. The aim of this study is to assess the legitimacy of source-separating wastewater systems from the perspective of wastewater professionals in Sweden. The study uses interviews and a survey to explore the pragmatic, normative, cognitive and regulatory dimensions of legitimacy and how these aspects can vary between different municipalities. It also looks into possible knowledge-based activities to increase legitimacy. The results from this study show variations in legitimacy levels in urban areas in Sweden. Overall opinion appears to be neutral to the concept rather than negative. Although many see multiple barriers to implementation. Normative legitimacy (moral motivation) was relatively high, while cognitive legitimacy (knowledge & experiences) was lowest. Respondents from organizations where source-separation is being implemented, or they believe that it will be implemented within 10 years, generally saw more drivers and fewer barriers. These innovators were also more interested in knowledge-based activities. Overall recommendations to increase cognitive knowledge regarding source-separating systems among multiple stakeholders seems the most promising path forward to increase legitimacy in the Swedish wastewater sector.

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.

Nikos Gyftopoulos is joining the Kretsloppsteknik-group for his master thesis project


Hello, my name is Nikos Gyftopoulos, I am from Greece, where I did my bachelors in Biology in the National Kapodistrian University of Athens, and now I am living in Uppsala.

I am doing my master’s programme in Applied Biotechnology at Uppsala University and I am presently doing my thesis in the Department of Energy and Technology of the Swedish University of Agricultural Sciences (SLU), with the Environmental Engineering Research Group. During the following months I intend to learn many aspects related to the bioconversion of organic wastes with black soldier fly larvae (Hermetia illucens, BSFL) and develop my thesis in this subject.

I will be supervised by Dr. IvĂŁ Guidini Lopes and Dr. Cecilia Lalander, and the project we will develop together regards evaluations of the inactivation patterns of microbial pathogens during the bioconversion of contaminated post-consumer food waste.

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: https://www.sciencedirect.com/science/article/pii/S0921344923003361 .

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.

Our latest publication on BSFL composting


Our latest publication on the dynamics of BSFL composting is just out in Waste management.

Around the world, many types of waste streams are (bio)converted with these insect larvae, and the treatment efficiency is dependent on the materials’ characteristics and rearing conditions. In this study, we evaluated the impact of these traits on the efficiency of this bioconversion.

We found out that the nutritional composition of waste is far from being the only factor that affect the efficiency of the bioconversion process. The number of larvae we add in one treatment unit impact on in the total yield of larval biomass (feed ingredient) up to a threshold at which point adding more seed larvae no longer increase the total yield of larval biomass. The depth and moisture of the biowaste was found to affect the larval survival and consequently, the overall process efficiency.

This study sheds light in how to establish several process parameters during waste treatment with BSFL, assisting waste managers and insect breeders on how to treat new waste streams with this insect larvae, promoting circularity in the sector.

If you are intrested to find out more, check the full article out.

Cecilia ska vara med och diskutera insekter i Framtidens Bonde


Framtidens Bonde Àr en webbinarieserier som diskuterar framtidsbranscherna, de gröna nÀringarna. PÄ tisdag den 12 september ska Cecilia Lalander frÄn Kretsloppsteknikgruppen vara med och diskutera om Insekter kan skapa nya intÀkter i jordbruket.

Om du vill anmÀla dig gÄr det att göra hÀr.

Om du vill vara med och lyssna:

Facebook: https://www.facebook.com/events/737189641508397

LinkedIn: https://www.linkedin.com/events/7097195613091487744/comments/

Youtube: https://www.youtube.com/watch?v=tpTDMVrmDcs

We will attend the INSECTA conference in Magdeburg on 13th of September!


Two members of the Kretsloppsteknik’s BSF group will attend the INSECTA 2023 conference in Magdeburg, Germany, which is being organized by Pilot Pflanzenöltechnologie Magdeburg e.V. (PPM), on September 13-14th. IvĂŁ Guidini Lopes and the PhD candidate Lovisa Lindberg will be presenting two ongoing studies on the topic of organic waste treatment with BSF larvae. IvĂŁ will hold an oral presentation regarding the inactivation of pathogens by BSF larvae in a large-scale setting, entitled “Safety assessment of black soldier fly larvae reared on food waste” and Lovisa will present her recent findings on the bioconversion of greenhouse waste with BSF larvae, also as an oral presentation entitled “Practical adjustments in fly larvae composting when treating plant-based waste”. The complete program for the conference can be accessed by clicking here.

If you’re also participating here, we would love to chat with you, perhaps over lunch or dinner during the conference! Feel free to send me an email or a message about this to iva.guidini.lopes@slu.se or lovisa.lindberg@slu.se.

Attending the world water week 2023


Chea Eliyan, a PhD student from the group attended WWW 2023 in Stockholm from August 20-24. WWW is annual event organized by SIWI. For this year, it sets out to tackle the questions under the theme, Seed of Change: Innovative Solutions for a Water-Wise World.

Many side events, exhibitions from various stakeholder, as well as a wide range of topics presented during those four days event. It was a great opportunity for her to learn and networking with different people in the field for her future career. Despite attended the selected sessions which are related to wastewater reuse and resource recovery, Eliyan got a chance to talk to some of the researchers from who she previously only had read their publications. It was an impressive event and Eliyan is looking forward to be part of it next year.