Enhancement of Oxidation Processes of Cellular Microbial Substrate, Using UV Radiation in Resonant Elliptic Cavity

Abstract

The improvement of disinfection efficiency for different contaminated fluid fluxes is related to the enhancement of oxidation processes at cellular level, developing original disinfection equipment. The construction of developed equipment is based on the amplification and focalization of UV germicide and bactericide radiation (wavelength l = 253.65 nm), using an elliptic cylinder shaped reflector and building up a resonant cavity for these radiations. Some theoretical considerations concerning the experimental device construction are described in the paper. The resonant elliptic cavity is used in LASER technique, as the �optic pumping� and this idea was involved in the developing of our equipment. Two TUV-60 lamps made by Philips Company were placed in the focal points of the elliptic cylinder (made by anodized aluminium) and a central quartz tube (symmetrical disposed between these lamps) was used as plug-and-flow photo-chemical reactor, through the fluid fluxes were passed. In these conditions the syntheses of chemical species with high oxidation capacity (hydroxyl radicals, ozone, etc.) can contribute to the advanced oxidation process of cellular microbian substrate. Distillated water and respectively an air flux contaminated with four types of pathogenic microorganisms (E.coli, Streptococcus sp., Salmonella sp., Pseudomonas aeruginosa) were used in all experiments. The best results were recorded in the case of gas flux due to synchrony of UV/Ozone effects when all pathogenic microorganisms were destroyed. In case of water flux were obtained the similar results, for E.coli and Pseudomonas aeruginosa. Salmonella sp. and Streptococcus, were still found in water after desinfection, as refractar pathogens in 34.3 % and respectivly 7.8 % in raport with initial CFU (104 colony formatting unities/mL).