Publications – Page 4 – Kretsloppsteknik

Special Issue “Biochar for the Environmental Wastewater Treatment”

Published 26 January, 2019
By Prithvi Simha

Flyer for SI: Biochar for the Environmental Wastewater Treatment Download

Sahar Dalahmeh, Researcher at our group along with Manfred Lübken is co-editing a special issue in the journal, Applied Sciences published by MDPI. The special issue focuses on “Biochar for the Environmental Wastewater Treatment”. Paper submissions are invited along the following lines:

Filtration systems are, in general, characterized as low cost, easy to operate and they have a low space requirement. Filter material should have, e.g., a large specific surface area, low bulk densities and should be locally available where wastewater treatment is to be installed. Recently, biochar has been demonstrated to be effective in the removal of organic and inorganic constituents, heavy metals or microorganisms from contaminated water. Compared to many other filter materials, biochar has the advantage that it can be produced from locally available biomass and can be used as a soil amendment after wastewater treatment. The aim of this Special Issue is to discuss both the potential and limits of biochar as a filter material for wastewater treatment.

New Publication on removal of per- and polyfluoroalkyl substances in onsite wastewater treatment

Published 23 January, 2019
By Prithvi Simha

In this study, we investigated the potential of biochar filters as a replacement or complement for sand filters for removal of per- and polyfluoroalkyl substances from wastewater in onsite sewage facilities. In a 22-weeks experiment, concentrations, removal and adsorption of nine perfluoroalkyl carboxylates (PFCAs; C3- 11) and three perfluoroalkane sulfonates (PFSAs; C4, 6, 8) and one perfluorooctanesulfonamide (FOSA; C8) were investigated in four treatments: biochar with active, biochar with inactive biofilm, biochar without biofilm and sand with active biofilm. We found that biochar with no biofilm achieved higher removal efficiency (90-99%) and the adsorption capacity (73 -168 ng g-1 ) for C7-C11 PFCAs, C6, C8 PFSAs and FOSA, than the other biochar and sand treatments. For all biochar treatments, shorter-chain PFASs were more resistant to removal than longer-chain PFASs.

New Publication: Health risks from wastewater irrigation in Bolivia

Published 21 November, 2018
By Prithvi Simha

In our latest study published in Journal of Water and Health, we assessed the pathogen flows in a water&nutrients reuse system for production of lettuce in a peri-urban zone in the highlands of Bolivia. Viral and bacterial indicators, and helminth eggs were quantified in soil, water and lettuce samples taken during one crop season, and then statistically processed to analyse the flows of microbial contamination throughout the system.

New Publication: Hygiene aspects of urine drying technology

Published 26 July, 2018
By Prithvi Simha

In a new paper published in Water Research, Senecal et al. assessed what hygienic health risks may occur when human urine is dehydrated. The experiment was set up to simulate that the last person using the toilet (before the dehydration medium is changed) is contaminating the medium with misplaced faeces, with no time for dehydration of the urine, i.e. a worst-case scenario. It was found that urine dehydration in itself achieved a concentration < 1 A. suum per 4 g of dehydrated medium which fulfils the WHO guidelines for unrestricted use.

New publication: Will Indian consumers eat urine-fertilised food?

Published 6 July, 2018
By Prithvi Simha

Decentralised sanitation technologies based on source separation of toilet waste have attracted a lot of research attention – the social sustainability of these technologies, not so much. To attempt to fill this gap, members of the Kretsloppsteknik group collaborated with researchers at VIT University, to explore what food consumers in India think of urine recycling. The results were recently published in the journal Water Research, where a survey of 1252 consumers at the VIT University campus revealed: 68% stated human urine should not be disposed but recycled, 55% considered it as fertiliser, but only 44% would consume food grown using it.

New publication on the drying of ion-exchanged human urine

Published 11 June, 2018
By Prithvi Simha

In a recent study published in Water Research, members of the Kretsloppsteknik group investigated the possibility of alkalising human urine by anion-exchange and dehydrating urine into a dry fertiliser powder.Fresh urine was passed through an ion-exchanger, stabilised by alkalisation (pH >10), added to an alkaline media (wood ash/alkalised biochar) and dehydrated

Simha, P., Senecal, J., Nordin, A., Lalander, C., Vinnerås, B., 2018. Alkaline dehydration of anion–exchanged human urine: Volume reduction, nutrient recovery and process optimisation, Water Research. In Press. doi: 10.1016/j.watres.2018.06.001.

Dry fertiliser from urine

Published 28 June, 2017
By Prithvi Simha

The saying ‘we are what we eat’ is only part of the story. What we eat is what we excrete, and this means plant nutrients. Human excreta contain the same nitrogen, phosphorus and potassium (N-P-K) as the fertilisers used to produce the food consumed (Winker et al., 2009). However, human excreta are considered unwanted waste throughout the world, creating humanitarian and environmental problems (Baum et al., 2013). In order to replace the nutrients removed from the fields during harvesting, more fertilisers are manufactured in industrial processes that are contributing to environmental changes at global level (Rockström et al., 2009). Recycling human excreta back to agricultural fields would reduce the current dependence on fossil fuel-derived fertilisers (Ramírez & Worrell, 2006). It would also improve crop yields in e.g. sub-Saharan Africa, where fertiliser application is low (FAO, 2015), and protect marine ecosystems in the Baltic Sea by limiting the flow of excess nutrients to surface waters (Rockström et al., 2009).