Globally, 2.7 billion people are using onsite sanitation systems, particularly in low income, high density settlements (LIHDS) in urban areas of developing countries. However, treatment technologies to manage the faecal sludge (FS) generated from these systems are often not in place, leading to high risks for environmental and public health. The development of replicable and effective technologies for FS treatment is key in addressing this challenge.
This research focused on development of an innovative FS stabilisation technology and addressed key constraints in anaerobic FS treatment: inadequate pathogen inactivation and limitations in biochemical energy recovery. The developed two-stage reactor system consists of an acidogenic reactor fed with mixtures of FS and market waste to facilitate pathogen inactivation, and a subsequent methanogenic plug-flow reactor for enhanced methane production. Due to its potential for application as an off-site FS treatment technology at any scale, receiving any type of faecal matter, collected from different types of sanitary systems, the system provides an option for FS stabilisation for LIHDS. Additionally, the research evaluated the limitations of sanitation provision in LIHDS, and proposes methods for creating an enabling environment for full-scale implementation of onsite systems. The presented results contribute to designing appropriate sanitation interventions in LIHDS.
Table of Contents
Thesis summary, General Introduction, An evaluation of the limitations of sanitation chain in low income, high density settlements, Build-up and impact of volatile fatty acids on E. coli and A. lumbricoides during co-digestion of urine diverting dehydrating toilet (UDDT-FS) Faeces, Volatile fatty acids (VFA) build-up and its effect on E. coli inactivation during excreta digestion in single-stage and two-stage systems, Anaerobic digestion of Urine Diverting Dehydrating Toilet Faeces (UDDT-FS) in urban poor settlements: Biochemical energy recovery, General discussion, conclusion and recommendations.
Ms Joy N Riungu is a researcher and founder of the Sanitation Research Institute, Meru University of Science and Technology, Kenya. She has vast experience in onsite sanitation, technology development, testing and implementation; in particular within informal slum and peri-urban settlements. Her PhD thesis ‘Off-Site Enhanced Biogas Production with Concomitant Sludge Hygienisation of Faecal Matter’ was based on slum sanitation and sought to diversify treatment options for faecal sludge collected from container-based sanitation.
Among the sanitation projects she is currently leading are: community based black soldier fly faecal sludge processing unit, onsite sanitation capacity building (MSc, short courses and diploma), biochemical energy recovery, enabling the circular economy for sanitation and sanitation enhancement in off-grid cities.
Her intervention point is to create a paradigm shift in faecal sludge management in Kenya for sanitation enhancement, environmental protection, energy, and food security.