Study On Influence Factors And Control Methods Of Corrosion Caused By Sulfate-Reducing Bacteria

Sulfate-Reducing Bacteria (SRB) may corrode metals seriously. So the study on preventing metal from SRB corrosion is becoming more and more important.In this paper, Sulfate-Reducing Bacteria (SRB), which gain from sea and mud near Dandong Power Company, is purified with solid mediums, conserved at low temperature and counted in Most Possible Number method. The bacterium is identified to belong to G' in both simple staining method and Gram's staining methodIn order to open out the relationship between cultivating pH, mineralization degree and SRB reproduction, the cultivating method of Three Test Tube is used. The result shows that SRB can reproduce while pH is during 5.0-9.5 and mineralization degree is during 7.5-30g/L.The effects of SRB in different oxygen environments on corrosion of A3 steel are studied through static cultivating experiments. The result shows that the corroded velocity of A3 steel by SRB in anaerobic environment is almost same as that in continual anaerobic-aerobic environment.The effects of power ultrasound on corroded velocity of A3 steel by SRB are studied through static cultivating experiments. The result shows that the corroded velocity of A3 steel by SRB in the intense power (320W) ultrasound enviroments for long time (10 minutes and 20 minutes) is obviously less than that in the non-ultrasound environment. While the corroded velocity of A3 steel by SRB in feebleness power (180W) ultrasound enviroments for short time (2 minutes and 5 minutes) is almost same as that in the non- ultrasound environment.Finally, the effects of bactericide on Sulfate-Reducing Bacteria are studied. The result shows that why SRB has drug- resistivity is due to its adaptability to bactericide. The drug- resistivity is neither steady nor cross-link with the bactericide of metronidazole.