Corrosion

Microbial Control Inhibits Corrosion

Controlling corrosion and bio-corrosion is critical to increase workers safety and environmental protection.

In aqueous environments, iron materials are corroded not only by purely chemical or electrochemical reactions, but also by microorganisms and their by-products, including enzymes, exopolymers, organic and inorganic acids as well as volatile compounds such as hydrogen sulfide. This is often referred to as microbiologically induced corrosion.

Combating Microbiologically Induced Corrosion

Biocides are commonly used to combat microbiologically induced corrosion, which can weaken equipment and create safety and environmental hazards.

It has been suggested that 50% of corrosion failures in pipelines are of this type.
Similarly, bacterial activity – mainly sulfate-reducing bacteria (SRB) – is known to be responsible for more than 75% of the corrosion in productive oil wells and more than 50% of the failures of underground pipelines and cables.

SRB Causes Hydrogen Sulfide

SRB in oil environments can cause the production of hydrogen sulfide (H2S), an extremely toxic and corrosive gas that is responsible for a variety of environmental and economic problems.

The biogenic production of H2S gas by SRB causes particularly serious economic problems for the natural gas and oil industry due to the highly toxic and corrosive nature of H2S. One of the key enzymes important in this biologic process is adenosine phosphosulfate reductase (APSr).

Microbial control technology is continually advancing to provide new solutions to problems such as the formation of H2S. Recently 15 compounds were discovered that are novel potential APSr inhibitors. Three of them have shown to be effective at inhibiting SRB in water from the oil industry.