Different aspects of the behavior of wettable and nonwettable filters in filtration processes were considered, including mechanisms of drainage of liquids from filters' surfaces, performance of combined wettable/nonwettable filters, processes of the removal of sticky particles by wettable fibrous media and the possibility of blockage of filters by solid particles. The air carriers used for the laboratory experiments in all the above projects had room temperatures (20-30 degreesC) so the effect of evaporation of liquids from the filter's surface was neglected. However? in many industrial and laboratory applications, the temperature and humidity of the air carriers could be in a range where the evaporation of the irrigating liquid is significant and has to be taken into account to avoid the filter blockage due to the insufficient irrigation. In this paper, the results of the investigation of the possibility of clogging of wet filters by solid particles as a result of evaporation of liquid from the filter's surface and consequently insufficient irrigation are presented and further steps towards design of industrial devices are discussed.