Sewage heritage: Imerys relies on the exceptional durability of SewperCoat® to reduce the environmental footprint of infrastructure

Increasing the resilience of structures to more than 35 years

Water transport and treatment infrastructure is regularly degraded by biogenic corrosion, a deterioration process observed in sewage networks. This phenomenon occurs when bacteria living on the walls of structures transform the H2S (Hydrogen Sulfide) released by septic effluents into sulfuric acid, which then attacks construction materials, both metal and concrete. Increasing the longevity of these infrastructures threatened by this corrosion appears to be a major operational challenge.

Where standard infrastructure may require repair every 5 to 10 years, the application of SewperCoat® allows this lifespan to be extended beyond 35 years. The effectiveness of this mineral solution has been proven in particular at a Hampton Roads Sanitation District (HRSD)treatment plant located in Newport News, USA, where, even today, the mortar applied in 1991 still protects this infrastructure.

This results not only in economic gains for owners but also in a concrete ecological act. Indeed, fewer repairs mean fewer construction sites, less concrete consumed, and therefore a tangible reduction in the impact caused by construction.

Calcium aluminate: a sustainable alternative to synthetic resins

Used since 1991, SewperCoat® is based on the unique properties of calcium aluminate, derived from a mixture of bauxite and limestone. Unlike competing solutions based on organic resins, this mineral mortar offers:

• Unrivalled resistance: A mineral barrier to the action of acidophilic bacteria and high resistance to abrasion;
• Quick and economical application: Its ability to be applied in wet environments and its return to service in just a few hours can often eliminate by-pass costs (the network diversion necessary to dry out the structure during a classic repair);
• Optimized carbon footprint: By avoiding frequent rehabilitation cycles, SewperCoat® is part of a low-carbon asset management strategy.

About Imerys

Imerys is the world’s leading supplier of mineral-based specialty solutions for the industry with €3.4 billion in revenue and 12,300 employees in 40 countries in 2025. The Group offers high value-added and functional solutions to a wide range of industries and fast-growing markets such as solutions for the energy transition and sustainable construction, as well as natural solutions for consumer goods. Imerys draws on its understanding of applications, technological knowledge, and expertise in material science to deliver solutions which contribute essential properties to customers’ products and their performance. As part of its commitment to responsible development, Imerys promotes environmentally friendly products and processes in addition to supporting its customers in their decarbonization efforts.

Imerys is listed on Euronext Paris (France) with the ticker symbol NK.PA.

Contacts

Mathieu Gratiot : + 33 7 87 53 46 60