(427m) Mass Transfer Effects in the Mic of C1018 Steel

Mass transfer is a very important parameter in biochemical engineering studies of fermentation. In microbiologically induced corrosion (MIC), mass transfer was linked to nutrient distribution in the medium and to the transport of corrosive species and corrosion products. It has been reported in literature that biocides were not as effective against sessile organisms within biofilms as they were against a planktonic population since it was difficult for biocides to penetrate the biofilms. In this work, mass transfer effects on the MIC due to sulfate reducing bacteria (SRB) were investigated. The ATCC 7757 strain of Desulfovibrio desulfuricans (a common SRB) was used to develop the biomass in this work. Results in 100 ml anaerobic vials indicated that mild agitation promoted planktonic and sessile SRB growth as well as pitting corrosion when compared to experiments with stagnant culture media, but further experiments using a very high rate of agitation hinted that SRB cell growth and metal corrosion were both hindered. It was likely that high shear inhibited cell growth and biofilm formation pointing to a potential mitigation method by using shear to control MIC.