The paper presents the results of a study of the filtering capacity of some filters from ceramic composite materials made on laboratory installation. The filtration process involved applying a pressure gradient to the filter by means of a centrifugal pump from the filter installation. The ceramic composite materials used to make the filters have a bentonite-based matrix. To achieve the porous structure, the matrix was reinforced with SiC and Al2O3 ceramic powders and to control the pore size, additional Al metal particles were added. The stages of obtaining and characterizing the filters, respectively of testing their filtering capacity of the suspended particles from the rainwater are presented distinctly. In conclusion, the dependencies between a series of structural and geometric characteristics of the filtering capacity were established.

The paper presents a method and an installation for determining the filtration capacity of filters made of composite materials with ceramic matrices. Applicable to fluid media (liquid, gaseous) the process is based on generating a pressure gradient in the filter area. The pressure difference between the two sides of the filter determines the passage of the fluid through the filter and its retention of the suspended particles. The process allows the testing of filters with a great diversity regarding the nature of the materials from which they are made, respectively their geometry and dimensions. In the present experiment, filters made of ceramic composite materials based on bentonite reinforced with SiC type ceramic powders and Al type metal powders were tested. From these materials were made cylindrical filters (diameters of 16 mm and length of 15 mm), which, after sintering at a temperature of 1250°C, were tested on the installation, for filtering rainwater samples. The determinations made highlighted a good ability of the filter to retain suspended particles in the water.