New technology for processing human waste in developing countries

The Bill & Melinda Gates Foundation has awarded Delft University of Technology (TU Delft, the Netherlands) a grant to 'Reinvent the toilet'. Aim of this project is to develop new technology for processing human waste without links to water, energy, or sewer lines, and at costs affordable to the poor in developing countries. 
 
The Bill & Melinda Gates Foundation announced this grant today at the AfricaSan conference in Rwanda (www.africasan3.com) as part of more than $40 million in new investments launching its Water, Sanitation, & Hygiene strategy.

Approximately 2.6 billion people on earth currently lack access to safe and affordable sanitation. The negative health impact of poor sanitation is enormous. To change this situation the toilet has to be reinvented.

Self-sustained

The ideal new toilet facility for developing countries must be self-sustained, affordable and without links to water, energy or sewer lines. Scientists from TU Delft now think they may have such a solution. They will use a grant from the Bill & Melinda Gates Foundation to develop their ideas into a working toilet facility for the billions who need it.

Microwave technology

Assistant Professor in the field of Process Intensification Georgios Stefanidis is one of the Delft scientists who came up with the initial idea. He explains: 'We will apply microwave technology to transform human waste into electricity. Starting from this innovation, we aim to realize a design and modular prototype for a full toilet facility that satisfies the urgent needs of users in developing regions of the world.'

In the first step of Delft University's new technical approach, the human waste will be dried. Then the waste will be gasified using plasma, which is created by microwaves in tailor-made equipment. This process will yield syngas, a mixture of carbon monoxide (CO) and hydrogen (H2). The syngas will then be fed to a solid oxide fuel cell stack for electricity generation.

Stefanidis: 'In order for the process to be energetically self-sufficient, part of the electricity produced will be used to activate plasma gasification, while heat recovered from the syngas stream and from the fuel cell exhaust gas will be used for waste drying. Preliminary calculations show that microwave plasma gasification may be energy self-sufficient, provided that efficient transformation and high throughput of human waste matter can be obtained. It is also affordable.'

Lasting sanitation solutions

Professor Andrzej Stankiewicz: 'The current project presents an excellent example of how modern chemical engineering science serves not only the chemical process industries but also helps in resolving some crucial societal issues in the world.'

'To address the needs of the 2.6 billion people who don't have access to safe sanitation, we not only must reinvent the toilet, we also must find safe, affordable and sustainable ways to capture, treat, and recycle human waste', said Sylvia Mathews Burwell, president of the Global Development Program at the Bill & Melinda Gates Foundation. 'Most importantly, we must work closely with local communities to develop lasting sanitation solutions that will improve their lives.'