Concrete Pipe Corrosion - Development of resistant concrete pipe for aggressive environments

Project start January 2014. Completed December 2015.

Summary:

This project aims at developing and testing various potential technologies for achieving greater resistance to hydrogen sulfide (H2S) attack on concrete pipes. H2S is generated by the anaerobic growth of bacteria in the waste water, and it represents the main cause of corrosion in concrete pipes. Usually, it is necessary to replace concrete pipes after just few years of usage in spite of a much longer life expectancy. H2S-degradation can shorten concrete pipes lifespan by as much as 70%. A municipal reform in Denmark (back in 2007) has led to the centralization of waste water treatment. This translates into long pressure lines and longer waste water residence time in the fully continuous pipe with no oxygen supply. Simultaneously, the centralized separation of sewage and stormwater increases the concentration of various chemicals in the waste water. This scenario promotes the formation of H2S, accelerating concrete degradation. Hence, the development of concrete pipes with improved resistance to for chemical attack is essential.

Objectives:

• Develop and test various potential technologies for achieving greater resistance to hydrogen sulfide attack concrete pipe at laboratory level.
• To develop a generic test setup, giving identical test conditions and the possibility of continuous measurements of concrete pipes resistance to hydrogen sulphide.
• Testing of one or two newly developed technologies into a full-scale wire construction.

Partners:

• Danish Technological Institute (Project manager), DK
• RC Concrete Products A/S, DK
• Aalborg Supply, Sewerage A/S, DK
• HOFOR A/S, DK