Biogenic Sulfide Corrosion
Definition - What does Biogenic Sulfide Corrosion mean?
Biogenic sulfide corrosion is a form of corrosion that is caused by sulfuric acid, which in turn is created by bacteria. Biogenic sulfide corrosion attacks materials such as steel and concrete. Biogenic sulfide corrosion is commonly a problem in the water and wastewater industry.
The biogenic sulfide corrosion process occurs when sulfates present in the environment are exposed to moisture and certain types of bacteria. The bacteria process the sulfates and turns them into hydrogen sulfide gas. The hydrogen sulfide gas then oxidizes and forms sulfuric acid. Sulfuric acid is corrosive to concrete, steel and many other materials. Sulfuric acid can also cause sulfide stress cracking.
Corrosionpedia explains Biogenic Sulfide Corrosion
Several factors affect the likelihood and the rate of biogenic sulfide corrosion. Higher temperatures often increase the bacterial processing of the sulfates and hydrogen sulfide gas, to a certain extent. Extremely high temperatures will kill the bacteria. To help limit the rate of biogenic sulfide corrosion, lower temperatures can be applied to the system.
Another necessary component of biogenic sulfide corrosion is sulfate. If very little or no sulfates are available, the biogenic sulfide corrosion process cannot occur. Also, the acidity of the fluid being transported must be at the right level. If there is an extremely high or low acidity in the system, the bacteria cannot survive. The amount of oxygen will also determine the likelihood of biogenic sulfide corrosion. If any of these factors can be controlled then the amount of biogenic sulfide corrosion that occurs in a wastewater system can be reduced.