To prevent the corrosion of sewer pipes without human intervention, researchers from the University of South Australia have developed a self-healing concrete.

According to its developers, the self-healing concrete features microcapsules filled with water treatment sludge for mitigating microbial corrosion. The sludge waste reportedly behaves as a healing agent, resisting acid corrosion and healing cracks.

Source: University of South Australia

Making the concrete resistant to microbially induced corrosion is that the microcapsules will feature a pH-sensitive shell and a healing agent core with alum sludge — which is a by-product of wastewater treatment plants — and calcium hydroxide powder.

The researchers explained that the alum sludge microcapsules embedded within the concrete — and consequently, its healing agents — will be released when the pH value of the concrete changes.

This system of self-healing cracks within sewer pipes without human intervention is expected to extend the lifetime of concrete structures as well as save potentially billions of dollars associated with the maintenance and repair of aging sewer pipes.