Dr. Ian Griffiths

Mathematical Institute, University of Oxford

Although water was once considered an almost unlimited resource, population growth, drought and contamination are straining our water supplies. Up to 70% of deaths in Bangladesh are currently attributed to arsenic contamination, highlighting the essential need to develop new and effective ways of purifying water.

Since arsenic binds to iron oxide, magnets offer one such way of removing arsenic by simply pulling it from the water. For larger contaminants, filters that alternate between porous and permeable walls in a striped fashion can help reduce contaminant build-up at the membrane surface that otherwise leads to blocking.

Here we develop mathematical models that describe each of these scenarios and show how the resulting models give insight into the design requirements for new purification methods.