Waste & Sanitation
Modular Humanitarian Sanitation Solution
Sistema.bio is a large-scale social enterprise that has installed 20,000+ animal waste biodigesters globally. The anaerobic biodigester developed by Sistema.bio transforms human waste to energy. To date, Sistema.bio has installed 120 units globally at households, schools, and for decentralized faecal waste treatment plants. The modular design makes it uniquely suited to humanitarian environments with a 20-year lifetime and a fast, masonry-independent installation. A limiting factor to the mass rollout of the biodigester is the need for secondary effluent treatment (pathogen removal) after the biodigester has produced gas. For this project, a prototype effluent pasteuriser (powered by biogas) has been developed to enable implementation and optimisation. The project proposes to operate a pilot biodigester + pasteurisation unit at a treatment plant in Kisumu, Kenya. The installation will include a 20m3 biodigester and a pasteurisation unit. Thermal calculations show that biogas derived should be sufficient to power a pasteuriser to treat waste.
The ultimate goal of the work is to bring a completely modular human waste treatment system to market for use in humanitarian settings. Provisional interviews with key stakeholders (incl. Red Cross, PeaceWinds Japan) have suggested that there is significant demand in humanitarian settings where safe management of human waste consistently a problematic issue that leads to ill health and loss of human life.
Focus Country: Kenya
Contact: Prof. Elizabeth Tilley
Parnters: external pageOPERO Services, Kenya, external pageSistema.bio
ETH4D Grant: ETH4D Research Challenges Grant
Real-time monitoring for faecal sludge dewatering in Lebanon
The sanitation needs of one-third of the world’s population are met by non-sewered sanitation. With an increasing awareness of the need for non-sewered sanitation, technologies for treatment of faecal sludge that accumulates in onsite is becoming important worldwide. One of the most important treatment steps is dewatering, as faecal sludge contains more than 95% liquid. However, established technologies for solid-liquid separation of faecal sludge have a large footprint and are time-consuming processes.The MEWS (Management of Excreta, Wastewater and Sludge) group at Sandec, Eawag (www.sandec.ch/mews) has conducted research on chemically-enhanced dewatering (addition of conditioners) and has shown that this is a promising option to optimize dewatering. However, it cannot yet be scaled up, as robust process control is lacking.
To fill this gap, this project tests for the prediction and control of conditioner dosage in the laboratory at Eawag. It focuses on total suspened solids (TSS) sensors, as TSS is difficult to measure in continuous operation and it has a great influence on conditioner dosing. Prior to being able to implement this solution, rigorous field-testing is needed. MEWS is collaborating with CubeX, a Lebanese start-up who are developing a mobile faecal sludge dewatering truck. The CubeX prototype is still missing a reliable and robust process control system to be able to operate the dewatering truck as a financially viable solution. In the scope of this project, the team will validate the use of TSS sensors for the optimal dosage of conditioners in order to scale up this solution for faecal sludge management in general, which is the missing step for a project on full-scale automated system for dewatering using conditioners.
Focus Country: Lebanon
Contact: external pageDr. Linda Strande
Partner: external pageCubeX, Lebanon
ETH4D Grant: ETH4D Pilot Grant