Search
Filters
Close

51317--9604-Mitigation of Severe Pitting Corrosion Caused by MIC in a CDC Biofilm Reactor

To study the effect of repeated biocide treatments to mitigate microbiologically influenced corrosion (MIC), we used a Center for Disease Control (CDC) biofilm reactor to generate and remediate corrosive biofilms on carbon steel coupons grown from a produced water sample from a salt water disposal (SWD).

Product Number: 51317--9604-SG
ISBN: 9604 2017 CP
Author: Timothy Tidwell
Publication Date: 2017
$0.00
$20.00
$20.00

Microbially influenced corrosion (MIC) of metallic iron surfaces can be attributed to two different mechanisms. Chemical MIC (cMIC) occurs when biological activities modify the local microenvironment by generating acid or excreting H2S which induces a corrosive process on the metal surface. Electrochemical MIC (eMIC) however occurs when corrosion is propagated via direct electron uptake from a metallic surface. In this study we used a once-through biofilm reactor to generate corrosive biofilms from an oilfield produced water sample from West Texas. Initially we screened two biocidal products on coupons from the biofilm reactor to determine which chemistry would best kill and remove the biofilm from the surface. Then we used the best performing biocide to batch treat the biofilm reactor every week for eight weeks to determine how quickly the biofilms would recover and if biocide treatment would mitigate the severe corrosion. During the first three weeks ATP quantification showed a consistent 90% percent reduction in sessile microbial activity after a four hour biocide batch and a subsequent rebound once the biocide was eliminated from the reactor while DNA sequencing showed that the treatments managed to permanently eliminate Methanocalculus a hydrogenotrophic methanogen linked to eMIC from biofilm reactor bulk fluids. Results from this study indicate that in addition to reducing the overall and corrosion-related microbial populations pitting corrosion was significantly reduced with a weekly batch treatment of the top-performing biocide.

Key words: Microbially Influenced Corrosion, MIC, eMIC, Biocides, DNA, ATP, Methanogens

Microbially influenced corrosion (MIC) of metallic iron surfaces can be attributed to two different mechanisms. Chemical MIC (cMIC) occurs when biological activities modify the local microenvironment by generating acid or excreting H2S which induces a corrosive process on the metal surface. Electrochemical MIC (eMIC) however occurs when corrosion is propagated via direct electron uptake from a metallic surface. In this study we used a once-through biofilm reactor to generate corrosive biofilms from an oilfield produced water sample from West Texas. Initially we screened two biocidal products on coupons from the biofilm reactor to determine which chemistry would best kill and remove the biofilm from the surface. Then we used the best performing biocide to batch treat the biofilm reactor every week for eight weeks to determine how quickly the biofilms would recover and if biocide treatment would mitigate the severe corrosion. During the first three weeks ATP quantification showed a consistent 90% percent reduction in sessile microbial activity after a four hour biocide batch and a subsequent rebound once the biocide was eliminated from the reactor while DNA sequencing showed that the treatments managed to permanently eliminate Methanocalculus a hydrogenotrophic methanogen linked to eMIC from biofilm reactor bulk fluids. Results from this study indicate that in addition to reducing the overall and corrosion-related microbial populations pitting corrosion was significantly reduced with a weekly batch treatment of the top-performing biocide.

Key words: Microbially Influenced Corrosion, MIC, eMIC, Biocides, DNA, ATP, Methanogens

Also Purchased
Picture for Adding it All Up - The Fate of Sessile Microbes Following Biocide Treatment.
Available for download

51316-7770-Adding it All Up - The Fate of Sessile Microbes Following Biocide Treatment.

Product Number: 51316-7770-SG
ISBN: 7770 2016 CP
Author: Timothy Tidwell
Publication Date: 2016
$20.00
Picture for Visualization and Quantification of Biofilm Removal for the Mitigation of MIC
Available for download

51315-6081-Visualization and Quantification of Biofilm Removal for the Mitigation of MIC

Product Number: 51315-6081-SG
ISBN: 6081 2015 CP
Author: Timothy Tidwell
Publication Date: 2015
$20.00