Physical and biological characterization of a seawater ultraviolet radiation sterilizer

• Published in: Radiation physics and chemistry (Oxford, England : 1993) England : 1993), 1994, Vol.43 (3), p.249-255
• Main Authors: Torrentera, Laura, Uribe, Roberto M., Rodríguez, Romana R., Carrillo, Ricardo E.
• Format: Article
• Language: English
• ISSN: 0969-806X; 1879-0895
• DOI: 10.1016/0969-806X(94)90187-2

The physical and biological characterization of a seawater ultraviolet (UV) sterilizer is described. The physical characterization was performed using radiochromic dye films by evaluating the uniformity of the radiant exposure along each lamp, the effect of the radiation from one lamp on the array of adjacent lamps, and by measuring the UV radiation absorption of seawater with respect to distilled water. The biological characterization was performed by measuring the amount of reduction of bacteria in stored seawater after different filtration and UV treatments. Among the filtration methods tested, differential filtration (5, 3 and 0.45 μm filters connected in series) caused the highest bacterial reduction factor of 60%. UV radiant exposures of 212, 424, 636 and 848 J m −2 yielded bacteria reduction factors of 99.86, 99.969, 99.997 and 100%, respectively, for populations of Vibrio and Pseudomonas bacteria present in stored seawater. It is concluded that the system is useful for water disinfection when 1, 2 or 3 lamps are on; when 4 lamps are used the treated water becomes sterile.