From Conventional to Biological Removal of Iron and Manganese in France

The physical–chemical processes historically used to remove iron and manganese from groundwater are reviewed and the problems typically encountered are discussed. Also described is how the most commonly used treatment (aeration plus filtration) led to the discovery of the biological phenomena that substantially improve treatment and subsequently to a new generation of biological treatment plants. Tbe principles and the advantages of such processes as well as their limitations are discussed.