Currently, there are many demands weighing on the methods of eliminating sludge from drinking and sewage water by settling. First, it is becoming essential to decrease the mass of sludge to be evacuated and then, to offer sludge with criteria of acceptability for incineration and reuse in land disposal. To achieve this, a new method, Saphyr® - enhancing the dewaterability, addresses the requirements of incineration and reuse in land disposal, thus achieving the end purpose.

Saphyr® is a process for the stabilizing and sanitization of sludge obtained from thickeners. The treatment consists in mixing chemical additives in a baffle tank with mechanical stirring. CFD is used to simulate the complex hydrodynamics induced by the stirrer for different types of sludge and thereby evaluate the efficiency of the mixing process.

Pathlines in the Saphyr® process
Images Courtesy of Veolia Environnement