Hydrogen Sulfide Corrosion of Concrete in Wastewater Systems: Stages in Aerobic Processes and Prevention

Dr. C. P. Kaushal

Volume : VIII, Issue : VIII, August - 2019

Hydrogen Sulfide Corrosion of Concrete in Wastewater Systems: Stages in Aerobic Processes and Prevention

Dr. C. P. Kaushal

Abstract :

Background: Hydrogen sulfide corrosion in wastewater systems is a result of dilute sulfuric acid (H2SO4) dissolving the cement matrix. The acid is produced by a complex process of chemical and biochemical reactions. Hydrogen Sulfide (H2S) is produced by an action of Sulfur Reducing Bacteria (SRB) in the liquid phase, and then in time, this gas is converted by Sulfur Oxidizing Bacteria (SOB) into H2SO4. The last conversion occurs above the liquid level under aerobic condition. Objective and Methodology: The objective of this study is to review previous years’ literature and understand the aerobic processes stages in H2S corrosion and suggest preventive measures to reduce/eliminate it. Result: The literature review suggests that SRB under anaerobic conditions in the submerged part of sewers facilitate reduction of sulfate ions and the production of various forms of sulfides. Conclusions: The formation of H2S and its escape from the liquid sewage is the reason for the H2S corrosion processes in the wastewater systems. Aerobic bacteria colonize on surfaces above the water line and convert H2S gas into dilute H2SO4 by means of a complex biochemical process.