According to the World Health Organisation, one billion people in the world have narrow access to clean water and 2.4 billion use alternative methods of sanitation. In many developing countries such as Senegal, without modern sewage systems, excrement is transferred from latrines and loaded into the nearest river or ocean affecting the water supply.
An Omni-Processor is a faecal sludge based mobile power generator. The Omni-Processor may be a safe, affordable way to recycle human excrement and to help more individuals improve their lives in developing countries. The technology provides a sustainable, self-sufficient option for sanitation and water treatment by allowing energy to be fed back into the process.
As part of the Global Development Program established by the Bill and Melinda Gates Foundation, the Omni-Processor proposes to produce a safe and valuable product, support a sustainable business model, be adaptable to changing conditions, be community based and utilise local skills and materials. Over 50 technologies have been identified for the treatment of excreta and production of energy and nutrient products. The Water Environment Research Foundation offer minimum operational criteria to guarantee the successful set up of technologies in developing countries including: simple and adaptable “free-standing” technology comprising minimal infrastructure independent of externally sources electricity, water and sewers. So far, only twelve technologies have been found to meet these criteria, the Omni-Processor venerated as most promising.
The Omni-Processor vision combines a range of technologies and processes coupled to convert excreta into renewable energy and soil amendment products. Stabilised organics (humus), nitrogen, phosphorus, and trace elements form the highest reuse potential from human excreta improving the soil profile and helping to achieve sustainable agricultural practices. Bioconversion through anaerobic digestion is presented as the principle starting step to biologically stabilise the raw organics and produce a valuable biogas in the process. Biogas is then utilised as an energy source wherever heat is needed such as cooking and space heating.
The second step in the process constitutes gasification creating an output of syngas resulting in relatively clean emissions compared to incineration. Thirdly, pyrolysis produces useful bio-oil in a complete treatment of sludge. Thermo-mechanical treatment, a low tech technology, then likely inactivates most pathogens; this is well suited to co-processing and may be coupled with anaerobic digestion. Finally, incineration constitutes a large volume reduction of the biological inputs and achieves complete pathogen inactivation. The process combines other incineration and may be applied at a large scale in the developing world.
The system is said to produce approximately 10, 800 litres per day and is projected to ideally serve approximately 1000 – 5000 people implemented at a neighbourhood level. Approximately 150 kW is generated when producing maximum power; however, a small amount of water may be produced. The system meets both United States FDA and World Health Organisation drinking water standards.
In summary, the process accepts a range of deteriorated feedstocks and co-processes these inputs into a locally valuable resource such as heat, fuel, compost, or water. It has a small-footprint, a stand-alone device processing fewer than five tons of desolate product per day to serve 1,000 – 5,000 people in an urban developing-world setting. This is estimated to cost a smaller amount than $10/person/year, when accounting for net costs and benefits and run as a stand-alone unit, independent of grid, water, or sewer systems. Looking ahead, the company aims to launch a pilot project in Dakar Senegal testing a system of sensors and webcams allowing for the control of the processor to be remote. This is expected to enable the continual development and measure the real-world performance of the technology.
How might emerging technologies in developing countries help individuals improve their sanitation and water treatment?