Comparaison de L'Activite Biologique de Differents Charbons Actifs en Grains Comparison of Biological Activity of Different Types of Granular Activated Carbons

In drinking water production plants, two phenomena occur into the granular activated beds: physical adsorption of organic matter, especially of micropollutants and biodegradation of a part of the dissolved organic carbon. In order to get a better understanding of the development of biological activity a comparative test has been studied on four GAC from different origins and way of manufacturing, and with various characteristics (porosity, density, specific surface,…). For that purpose, preliminary experiments led to the choice of an organic compound, nitro-4-phenol, which presents an average biodegradability. Four minicolumns, each one filled with one GAC, plus another one filled with sand (as a non-porous reference material) were run in parallel at a flow rate of 0.5 l h−1 (i.e. a linear velocity of about 5 m h−1). In the first step of the test, GAC were saturated in batch with an aqueous solution of nitro-4-phenol at a standard temperature of 25°C. In the second step, columns of GAC were fed with a sol...