Imerys develops Sewper Liner to address H2S corrosion

At last week’s Singapore International Water Week (SIWW) 2022, Imerys debuted Sewper Liner, a calcium aluminate solution dedicated to the protection of new wastewater assets.

Imerys is committed to developing innovative, sustainable solutions for the construction industry and supporting the trend towards more environmentally friendly buildings and infrastructure. This innovation is a part of these sustainable construction solutions and was developed by the science and technology team at Imerys’ Technology Centre in Lyon to provide the highest level of durability against hydrogen sulfide (H2S) biogenic corrosion.

H2S occurs naturally as a compound in wastewater conveyance or collection systems, where it can be released as a gas under acidic or turbulent conditions. Thiobacillus bacteria present in the system react with the H2S gas, forming sulfuric acid, which, in turn, corrodes sewer pipes, weakening concrete structures and ultimately reducing the asset’s lifespan and increasing the risk of dangerous sewer collapse.

The key, of course, is not leaving reactive surfaces untreated. A solution that addresses H2S biogenic corrosion is the spraying of polymer liners, such as epoxy. However, this might lack durability as it often fails after a few years.

Designed to achieve long-lasting protection on dry, flat and smooth walls of new concrete assets, Sewper Liner is based on the same technology as Imerys’ SewperCoat solutions. It is three to five times thinner than SewperCoat, according to Imerys, making it ideal for the larger, flat surfaces of new wastewater concrete assets.

It can be sprayed quicker, speeding up the construction process. This, in turn, keeps the costs down without compromising long term H2S corrosion resistance and durability associated with calcium aluminate technology. Sewper Liner can also be applied to existing cracks, providing a thin layer of mineral protection that efficiently and rapidly bonds and covers a large surface area of dry concrete walls, resulting in higher durability with lower environmental impact.