A study on the potential of metal corrosion by sulfate-reducing bacteria in animal buildings

rite potential of sulfate-reducing bacteria (SRB) to cause metal corrosion in animal buildings was examined in this study. An analysis was done on the bacterial colonization and the corrosion products on the surfaces of metal s exposed to three animal buildings and one environmentally controlled buil ding over a two-year period. Data from this study showed that the levels of SRB on metal surfaces were low after two-year's exposure (maximum count: 1 .7 x 10(4)/cm(2)). SRB colonization levels after two years were not suffici ent to corrode metal products exposed in animal environments. In addition, metal surface analysis data using X-ray photoelectron spectroscopy showed t hat the corrosion compounds formed on the surfaces of different metals were not due to the SRB-induced corrosion mechanisms. These compounds were main ly oxides and carbonates (FeO, Fe2O3, Fe3O4, and Fe(CO)(5) on iron samples; ZnO and ZnCO3 on galvanized steel samples; Al2O3, ZnO, and ZnCO3 on Galval ume samples), and were normally generated due to the classic types of corro sion mechanisms. Some sulfur was present to form ZnS on the galvanized stee l samples, but might not be attributed to SRB. The origin of this sulfur wa s not clear.