THE EFFECT OF IRON-OXIDIZING BACTERIA ON CORROSION OF CARBON-STEEL INTAP WATER OF ST-PETERSBURG CITY

The effect of the microbiological factor on the corrosivity of the Nev a River water on a carbon steel (St3) was estimated. It was discovered that sulfate-reducing and nitrifying bacteria are practically absent from St. Petersburg tap water. However, iron-oxidizing bacteria (IOB) were detected in concentrations of (2 - 9)x 10(3) cells/l regardless o f the season, and comprise more than 50 species. The effect of 13 of t hese species on the corrosion of St3 was studied, and the microbial co ntribution to the overall corrosion rate in St. Peterburg's tap water was found to be up to 30 - 35%. Certain species of IOB were able to ac celerate corrosion by a factor of two.