ИСТИНА

The radiation resistance of the filter materials has great importance for removal of the solid radioactive impurities from gas and liquid phases. One of such materials, widely used in radiochemical industry, is cermet filter elements. But, this filtering material after carrying out of some cycles «filtration - regeneration» is irreversible stopped up by the solid phase and should be taken from devices and replaced, that leads to the formation of additional amounts of high level radioactive solid wastes. To overcome this problem with retention of high radiation resistance we developed the new spiral filtering element with variable surface for fine decontamination of gases and liquids from solid radioactive impurities. This spiral filtering element consists of a filtering partition, a cover, the union, a skeleton and spring. The filtering surface is produced from the corrosion-proof wire with a diameter from 0.6 up to 0.8 mm and represents a screw cylindrical spiral between of its coils with the special image carried out the filtering backlashes: their size can be from 3 up to 300 micron; diameter of a filtering partition - 16 mm; its length - up to 370 mm. From one end the filtering partition closes by cover, and another end has the union with external groove М16х1.5. The coaxisility of coils is provided with a skeleton. Sixty spiral filters make 1 m2 of a filtering surface. Dimensional diameter and length of spiral filter make according to 25 mm and 415 mm. Spiral filter are established vertically by unions upwards or downwards. The spiral filtering elements provide for a complete reduction of the filtering properties of the units after each cycle "filtration-regeneration", which is currently not feasible in filters of other types (metal ceramics, fabrics, cardboard etc.). Main advantages of new spiral filtering element are high reclaiming qualities in comparison with standard filtering.