Researcher Highlight — Asad Kwaja

Today’s researcher is Asad Kwaja, who completed the work for his mechanical engineering MEng at the University of Surrey in 2013. His project, working with the NGO Water for People, focused on two current hot topics — sustainable energy and the disposal and recycling of solid human waste. It is also relevant to another hot topic in development research — projects addressing urban rather than rural problems and needs which have been the primary concern of development work to date.

Water for People was looking for a way to cheaply, quickly and effectively treat solid human waste extracted from toilet pits, to make it easier and cheaper to transport and safe to use for fertiliser. The intention was for private sector entrepreneurs to use the results to start small businesses transporting, treating and selling the product in Blantyre, Malawi.

Asad studied the current situation, gathered information, created a theoretical model of the treatment process, and designed a prototype for testing on site. His solar-powered drying box has a glass area of about 3.6 square metres, and should be able to dry and sterilise a 200L barrel of sludge in one to two weeks. After this treatment the sludge would be reduced about 30% in volume and about 40% in mass, and be free of any harmful bacteria or parasites and safe to use as fertiliser. It is expected that these devices could be built locally from cheap and easily-obtainable materials, and would be easy to use and incorporate into day to day practices.