COMPARISON OF THE EFFICIENCY OF SOME FILTER MEDIAS

The relevance of research. The analysis of prospective for Ukraine filter medias was carried out. The characteristics, advantages and disadvantages of zeolite and foam polystyrene filter medias are presented. The mechanisms of colloids retention from suspensions (source water as a colloidal system) in zeolite and foam polystyrene filters were described. The colloids potential of the source water was determined. The comparison of the operation of these filter medias when using the surface waters of the upper Dniester River is presented. The main limiting factor of this source water is turbidity, respectively, the reduction of water turbidity was compared when using these two filter medias. The following characteristics of these filter medias were determined: dirt intensity, operation period between flushing and a volume of flushing water. The perspective trends in designing filter schemes and structures based on these filter medias and the ways of improving the adsorbing properties of foam polystyrene filter media were established. Research results. The negative charge ζ of colloids potential that causes the turbidity of the source water is a feature of surface natural waters being complex colloidal systems. That was proved by our experimental studies of the surface waters of the Upper Dniester River. Based on the results of the study the value of ζ - the colloids potential in this water is 9.41 mV. The penopolystyrene is an inert filter media with a positive ζ – potential, that is 2 mV, so the adsorption of colloidal particles occurs due to the potential difference. That is evident most clearly using the example of the colonies of cyanobacteria. Conclusions. The mode of operation of the zeolite filter media differs from the mechanisms of colloids retention when using foam polystyrene filters. Zeolite has ion-exchange properties, due to which the cations retention occurs at the beginning of the filtration cycle. Then it starts to function like a normal inert material, due to the phase difference and the developed specific surface. Accordingly, the effect of ζ - zeolite potential in the process of colloid retention is much lower, since zeolite has a negative ζ - potential. If you combine the filtering characteristics of zeolite and foam polystyrene, then a filter media with very promising properties will be obtained.