Use of ozone as a biocide in cooling water systems. Laboratory studies about its biocidal efficacy and effect on the corrosion of mild and stainless steel

VIERA, M.R., GUIAMET, P.S., DE MELE, M.F.L., VIDELA, H.A.

CORROSION REVIEWS

Freund Pubishing House

Año: 1993 vol. 11 p. 177 - 195

0334-6005

Fundamental aspects of generation methods used to produce ozone and its physical-chemical characteristics have been summarized. Benefits and disadvantages of the use of ozone as a biocide have been discussed including cost and economy of its use and the effect on the corrosion of the metallic components of cooling water systems. Additionally, results of experiments concerning the effect of ozone on both aerobic and anaerobic biofilms have been reported on biofilms formed on SAE 1020 carbon steel and AISI type 304L stainless steel (SS). Biocidal effciacy as a function of contact time and surface nature was studied. Results showed that, in the case of SS, ozone was effective not only in killing bacteria but also un facilitating the detachment of the biofilm as well. Electrochemical behaviour of each metal was also analyzed and no significant differences in the current/potential relationships of the steel either in the presence or in the absence of ozone were observed