Copper Tube Pitting in Santa Fe Municipal Water Caused by Microbial Induced Corrosion

Materials

Thomas D. Burleigh²  Casey G. Gierke¹  Narjes Fredj² 

[1] Earth & Environmental Sciences, New Mexico Tech, Socorro, NM 87801, USA; E-Mails:;Materials & Metallurgical Engineering Department, New Mexico Tech, Socorro, NM 87801, USA; E-Mail:

关键词: copper;    pitting;    microbes;    SEM;    biocorrosion;    microbiologically influenced corrosion;    MIC;    microbial induced corrosion;    tap water;    municipal water;   

DOI  :  10.3390/ma7064321

来源: mdpi

【 摘 要 】

Many copper water lines for municipal drinking water in Santa Fe, New Mexico USA, have developed pinhole leaks. The pitting matches the description of Type I pitting of copper, which has historically been attributed to water chemistry and to contaminants on the copper tubing surface. However, more recent studies attribute copper pitting to microbial induced corrosion (MIC). In order to test for microbes, the copper tubing was fixed in hexamethyldisilazane (HMDS), then the tops of the corrosion mounds were broken open, and the interior of the corrosion pits were examined with scanning electron microscopy (SEM). The analysis found that microbes resembling actinobacteria were deep inside the pits and wedged between the crystallographic planes of the corroded copper grains. The presence of actinobacteria confirms the possibility that the cause of this pitting corrosion was MIC. This observation provides better understanding and new methods for preventing the pitting of copper tubing in municipal water.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.