CEU eTD Collection (2016); Simha, Prithvi: Technological and Psycho-Sociological Perspectives on Closing the Sanitation Loop

CEU Electronic Theses and Dissertations, 2016
Author Simha, Prithvi
Title Technological and Psycho-Sociological Perspectives on Closing the Sanitation Loop
Summary To promote circularity in sanitation, this thesis examined the development of a process that could make nutrient recycling from human urine as attractive as the use of synthetic fertilisers in agriculture. Through a psycho–sociological lens, it also analysed attitudes among 120 South Indian farmers towards re–use of human excreta. The technological approach proposed here takes advantage of source–separation in urine–diverting dry toilets and integrates it sequentially with anion–exchange and alkaline dehydration processes. For stabilisation and nutrient preservation, urine was subjected to ion–exchange using a strong–base resin. A sieve–based urine drying unit was designed and operated to evaluate the nutrient recovery potential of wood ash and biochar in different protocols. The combined processes resulted in >97% water removal, >70% N retention and complete P and K recovery from urine. High drying rates suggested less than 10 kg of ash per month would be required to process the urine from an entire household in just 4.15 days; thus, every individual could be made accountable for just 21–64 kg of nutrient rich products (urine+drying media) instead of 500 kg of waste (urine) each year. The farmer surveys provided insights into factors that encourage or discourage adoption of ecological sanitation technologies. Nearly half the farmers took a positive stance towards the use of human excreta in agriculture. To initiate a positive–cascade effect and proliferate recycling practices among farmers, a conceptual approach was suggested. Combining the technological and sociological perspectives, it was demonstrated that, the toilet, a simple innovation and part of everyday life holds tremendous potential to bridge the technology–society gap and promote environmentally conscious behaviour among users.
Supervisor Illés, Zoltán
Department Environment Sciences and Policy MSc
Full texthttps://www.etd.ceu.edu/2016/simha_prithvi.pdf

Visit the CEU Library.

© 2007-2021, Central European University