COVER STORY
Repairing concrete with concrete in sewer systems Hydrogen sulfide (H2S) gas build-ups within wastewater networks are the main cause of accelerated biogenic corrosion in concrete structures. Unless countered, H2S will significantly shor ten the life of infrastructure assets, but there’s a proven solution using specialty calcium aluminate cements and aggregate products developed by French multinational Imer ys, operating locally as Kerneos Southern Africa.
A
pioneer in its field, Kerneos Southern Africa registered its first patented product, Ciment Fondu®, in 1908. This calcium-aluminate-based hydraulic binder, which is supplied to this day, was the forerunner of a series of proprietary innovations in the refractory, infrastructure and general industrial sector. A groundbreaking one for the wastewater industry was the introduction of SewperCoat® in 1991, which celebrates 30 years of successful application worldwide, including South Africa – a country widely regarded as an early adopter of the technology. SewperCoat’s unique aluminate cement and aluminate aggregate composition is a
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IMIESA July 2021
Removing spalled concrete caused by severe corrosion
A refurbished section of a wastewater treatment plant sprayed with SewperCoat
purpose-designed corrosion inhibitor and protection coating used to preserve most sewer infrastructure assets. These include iron and precast concrete pipes, manholes, pump stations, and concrete infrastructure in wastewater treatment plants. Application techniques include low-pressure wet spraying, high-pressure dry spraying, as well as rotational spinning head spraying.
