Blog from the Environmental Engineering Research Group at SLU
Prithvi was interviewed by Shivangi Agarwal from DownToEarth, the fortnightly magazine focused on politics of environment and development, published in India by the Centre for Science and Environment. They wanted to know what are the benefits of urine recycling and how it can be applied in an Indian context. To find out more, click here.
Swedish National Television SVT visited urine group yesterday and interviewed Prithvi about urine drying and our planned project in Gottland this year!
If you want to know more, check out the full interview below:
https://www.svt.se/nyheter/lokalt/uppsala/uppsalaforskare-sa-kan-atervunnet-kiss-radda-varlden
https://www.svt.se/nyheter/lokalt/uppsala/sa-gar-det-till-nar-urin-blir-godsel
Timely with the decision from the EU to adopt a regulation that governs the production and use of insect frass on the EU market ((EU) 2021/1925) we have compiled a review article published in the Journal of Waste Management on state of knowledge of using BSF larvae frass as an organic fertiliser. We have outlined the advantages of using BSF larvae frass as organic fertiliser that has been found so far, discussed possible additional benefits that have not yet been demonstrated, pointed to some of the challenges that could be faced using this fertiliser as well as elucidated the gaps in knowledge that currently exist. If you want to find out more, read here.
A seminar was held at the Norwegian water association in Oslo focusing on circular sanitation solutions in Norway. Björn participated and presented his vision for of the sanitation system of the future – being off-grid and fully circular inside a house. The vision is far ahead of the discussions about how we should treat our wastewater today. Most systems needed for a fully circular sanitation system already exist today, though they are still yet to be combined.
At the moment, Norway is facing major investments in the water and wastewater sector with a goal to bring down the environmental pollution. Hamse Kjerstadius from NSVA in presented their system with source separation installed in the city center of Helsingborg. His motivation for this implementation was economy and the environment. There were also several presentations from Norwegian delegates showing that under some specific circumstances source separating systems are economically more feasible when combining local and central treatments. One important factor lifted at the seminar, and that is true for Sweden as well, is that many of the regulations and legislations are unclear when it comes to sanitation that is not based on current conventional system.
The seminar was attended by people from academia, industry, and municipalities, where all were united in the vision of source separating system as the wastewater technology of the future.
Alkaline urine dehydration, function and system.
Decentralised sanitation systems based on source separation and urine recycling can contribute much to the existing wastewater regime. Prithvi Simha and Bjorn VinnerÄs show how innovative technologies such as urine drying can improve the circularity of sanitation systems. Read the full article here: https://www.thesourcemagazine.org/the-disruptive-opportunity-for-mainstreaming-urine-recycling/
Check out our latest article, a collaboration with the Zifu Li group at USTB Beijing that was published in the journal Resources, Conservation and Recycling:
Zhou, X., Simha, P., Perez-Mercado, L. F., Barton, M. A., Lyu, Y., Guo, S., … & Li, Z. (2022). China should focus beyond access to toilets to tap into the full potential of its Rural Toilet Revolution. Resources, Conservation and Recycling, 178, 106100.
Abstract: In China, over 47 million toilets in rural areas have been upgraded since the nationwide sanitation program, popularly referred to as the âtoilet revolutionâ, was launched in 2015. However, little is known about the perceptions of rural households regarding these new toilets or the fate of human excreta collected using them. To investigate the other side of the toilet revolution, we surveyed 980 rural households from 22 provinces across China in 2020. We found that most households used an on-site sanitation system (i.e. septic tanks and pit latrines), where urine and feces were mixed and collected (88%), stored in pits or tanks (79%), emptied by the households themselves (60%), applied on farmland as fertilizer (45%), or used for biogas production (5%). Despite the toilet revolution-driven infrastructure upgrade, only 25% of the households were satisfied with their sanitation system and pointed to health risks from issues in the toilet interface and the treatment and reuse of excreta as areas of concern. The majority preferred an âout of sight, out of mindâ approach, in which the local government handles excreta without involving the households and without asking them to pay for such management. Meanwhile, 80% supported the idea of local nutrient recycling and believed that human excreta should return to farmland as fertilizer or used for biogas production. Our findings suggest that decision makers in local governments across China must urgently explore ways to upgrade all parts of the sanitation service chain so that rural sanitation can be truly improved to positively influence the progress on other national sustainability goals.
In our latest publication on black soldier fly larvae (BSFL; Hermetia illucens) composting, we investigated the impact of pre-treatment on process efficiency and greenhouse gas emissions. We evaluated BSFL composting of broccoli and cauliflower cuttings and orange peel with and without pre-treatment, and compared the results to those for food waste (control). The two pre-treatments we investigated were a 2 w inoculation with 1) the fungi Trichoderma reesei or 2) ammonia solution. The hypothesis was that the fungi would break down cellulose and hemicellulose to easily available carbohydrates, while the idea with the ammonia pre-treatment was that it would both break cellular structure and add nitrogen for the microbial community to assimilate into proteins.
We went on a study trip to the waste management company VAFAB in VĂ€sterĂ„s with students from our two courses about waste management, âSafe nutrient recycling 15HPâ and âWaste management 5HPâ. A very interesting tour that gave insights about the volumes of waste that we all generate, among the things we visited we had a bus tour over the 45 hectar old landfill. Additionally we had a nice tour of the newly re-built biogas plant and hear about the challenges they had with sediments in the reactors from egg shells, sand and dirt that consumes reactor volumes. The produced biogas is used for the local buses and the bio-fertiliser is collected by local farmers for free.
Food waste bags that have been collected in the VÀsterÄs region are stored before they are feed to the anaerobic digester.
Last week our main building MVM, which contains our offices and laboratories, turned 10 and we all celebrated together! Many bright brains have entered and left this building in the past 10 years, so to catch up with the current staff, some of us took the celebration as an opportunity to present their group to our fellow colleagues. Nothing better than a stroll through our diverse work place, with Fika and coffee afterwards!
Speaking of Fika: The fly larva had their own version of Swedish Fika, two boxes containing 10.000 larva each were fed (vegetarian) hamburgers and cake and our colleagues could vote on menti.com which of the two meals would be gone first! It was a tight race but in the end the larva clearly preferred the cake! Who can say no to some easily available carbs in winter!