Dr Ian Griffiths, Dr Raka Mondal (Mathematical Institute)
Professor Sirshendu De, Dr Sourav Mondal (Indian Institute of Technology Kharagpur)
The Ganges–Brahmaputra Delta is a global hotspot for arsenic groundwater contamination. Naturally occurring arsenic concentrates in water drawn from deep wells, creating a major public health issue in West Bengal and Bangladesh, which has been described as the largest mass poisoning of a population in history.
A novel technology has recently been discovered by Griffiths’s collaborator, Professor Sirshendu De (IIT Kharagpur), which uses naturally abundant laterite soil to filter arsenic. The technology has the potential to provide a global breakthrough, supplying clean water to the world. However, to achieve this, a sound quantitative understanding of its performance is essential, which can only be obtained through the development of mathematical models.
Griffiths has developed a mathematical framework using homogenization theory and asymptotic analysis that distils the complex process into a simple predictive tool, which predicts the two key features: how frequently filters must be replaced, and how the filters may be upscaled to serve, for example, a school or community.
The filters serve more than 5000 people, and 40 community-scale filters are now being deployed. The mathematical tools provide the essential guidance needed for engineers to maintain current filters and deploy these new filters in a cost-effective manner.