This paper presents a study regarding the purification degree of waste water using porosil like filler material. The experiments were realized using a factorial 33 Experiment design, intending, in the same time, to realize the mathematical simulation and optimization of germs retention by filtered surfaces. The mesophilic germs content of sewage samples are influenced by filtered media characteristics and by physico/chemical properties of sewage. The results obtained are donned in tabular and graphical forms.
