Reinvent the toilet: Phase 2

Reinvent the Toilet Challenge – Phase 2

Grant No. OPP1069575: Data Acquisition and Field Support for Sanitation Projects

May 2013 – June 2015 (with an extension to June 2016)

Partner Organisations: eThekwini Water and Sanitation

Project Description:

The project awarded to the Pollution Research Group (PRG) built on the knowledge, strengths and experience gained by the team during the Phase 1 implementation. The objective was to characterise physical and chemical properties of excreta streams from dry on‐site sanitation systems or from decentralized low‐water consuming sanitation systems. The data were then passed to other grantees for use in their research.

Assistance was provided to other Bill & Melinda Gates Foundation (BMGF) grantees in establishing and evaluating their prototypes in Durban, and providing a support of their work by:

  • obtaining experimental data of a range of excreta streams,
  • undertaking generic process investigations on selected excreta streams,
  • developing process models of material flows and transformations,
  • facilitating field trials for BMGF grantees in Durban, and
  • obtaining data from other African countries (either field or from prototypes) in the last few months of the project.

In order to achieve these aims, the following activities were undertaken:

  • a survey of the needs of the other BMGF grantees in terms of data requirements, laboratory assistance, field work and spending time in Durban;
  • the provision of existing data regarding sludge, faecal and urine characteristics;
  • the recruitment of Masters students to undertake investigations into various aspects of the project in order to obtain further data;
  • using the data from student projects to undertake process modelling;
  • providing access to the PRG laboratory for visiting grantees and assistance with analyses;
  • facilitating access to various sites within the eThekwini Municipality for field testing of prototypes in conjunction with eThekwini Water and Sanitation (EWS);
  • making contact with other organisations within Africa in order to determine capabilities for testing of faecal sludge and provision of samples.
  • A series of reports (Masters dissertations) on the following topics:
    • Thermal Properties and Drying Characteristics of Faecal Sludge
    • Rheology, Extrusion and Pelletisation of Faecal Sludges
    • Forward Osmosis as a Final Step in the Recovery of Water from Urine
    • Micro-filtration of Liquid Excreta Streams
    • Separation Products of Urine
    • Nano-filtration of Liquid Excreta Streams


Main Outcomes:


  • An extensive data base on the physical, chemical and microbiological characteristics of excreta waste streams from different on-site sanitation systems.
  • The realisation of the important role PRG has in providing support to other Grantees in Feacal sludge management and the development of on-site sanitation technologies.


Publications and reports

Journal Papers

J. Ouma, S. Septien, K. Velkushanova, J. Pocock and C. Buckley (2016). Characterization of ultrafiltration of undiluted and diluted stored urine. Water Science and Technology. In press (2016).

J. T. Radford, C. Underdown, K. Velkushanova, A. Byrne, D. P. K. Smith, R. A. Fenner, J. Pietrovito and A. Whitesell. (2015). Faecal sludge stimulants to aid the development of desludging technologies Journal of Water, Sanitation and Hygiene for Development Vol. 5 No. 3, pp 456–464, IWA Publishing 2015, doi:10.2166/washdev.2015.014


Reinvent the Toilet Phase II: Data Acquisition and Field Support. Displayed at the Toilet Fair in India, March 2014.

Conference Papers and Presentations


Reports and other:

  • Recipe for synthetic sludge simulant for the Bill and Melinda Gates Foundation’s Reinvent the Toilet Fair: India 2014. The recipe used to simulate faecal sludge for the Toilet Fair
  • Selection of synthetic sludge stimulant for the Bill and Melinda Gates Foundation’s Reinvent the Toilet Fair: India 2014. A comparison of the various recipes for faecal sludge
  • RTTC flow diagram: Process flow diagram showing the linkages between the research being conducted on excreta streams by the PRG and the prototypes being developed by other Gates Grantees.
  • Phase 2 Flyer: A fold out booklet prepared for the Toilet Fair held in India in March 2014 outlining the Reinvent the Toilet Challenge Phase 2 activities of the PRG.
  • Phase 2 booklet: A booklet prepared for the Toilet Fair held in India in 2014 detailing the work carried out by the PRG under Phase 2 and related projects. Information on each of the Masters Research projects is included, as well as a summary of the data obtained during the course of the project.]
  • DVD outlining the work carried out by the PRG