General Idea about what really Microbiologically induced. Corrosion is and how active Iron reducing Bacteria in this process.

1.
Microbiologically induced Corrosion
(MIC)
caused due to iron reducingbacteria
(IRB)

2. What is MIC?
! Metabolic reactions of microorganisms on a
metalic substratum.
! These reactions refer to biocorrosion.
! Performed by various bacterias:
sulfate-reducing bacteria,
acid-producing bacteria,
fugii,
and
iron-reducing bacteria.

3. Biofilm Formation
! Bacteria Adhere to the
surface.
! Production of Extracellular
Polymeric Substance(EPS).
! Advantages of EPS

4. Role of IRB in MIC
! IRB strains are capable of reducing
insoluble ferric iron to soluble
ferrous iron.
! IRB are postulated to accelerate
corrosion by the following actions:
1. Removal of the protective
corrosion scales formed on exposed
surfaces.

5. SRB(Sulphate Reducing Bacteria) shadowing IRB
! Detailed studies are carried out about the MIC caused by SRB, which
underestimates the role of IRB in MIC.
! IRB are able to metabolize other different electron acceptors including
Mn(IV),NO3–, NO2– , SO3.
! Thus need for more detailed study.

6. Detection of MIC
! Three broad categories of techniques used to detect
and monitor MIC are:
1) Surface inspection,
2) Microbial sampling and identification,
and
3) Corrosion rate determination.

7. Preventive / Control Methods
! Coating
Polymeric coating.
polyurethane, silicone, epoxy resins, etc
! Cathodic Protection.
Cathodic protection reduces bacterial adhesion and reproduction of aerobic
bacteria during the eaidy stages .
! Counteract the actions of Bacteria. (Biocides)

8. THANK YOU