New concrete coating offers hope in fight against sewer blockages

A fatberg is a large mass made up of hardened fat, oil, and grease that can cause serious problems in our sewer systems. It forms when these substances are poured down drains and mix with other waste, eventually clogging the pipes and blocking the flow of water. This can lead to major disruptions and costly repairs.

Engineers at RMIT University,Melbourne have come up with a new way to protect concrete pipes—by developing a special coating. This innovative solution helps safeguard the pipes and improve their durability. This could greatly reduce the buildup of massive fatbergs in the sewer systems.

According to a report from Interestingengineering.com, lab tests revealed that the coated concrete had 30% less buildup of fat, oil, and grease.

What's interesting is that this coating not only helps stop fatbergs from forming but can also repair itself.It can fix itself, which makes it last longer and provides ongoing protection.

Addressing F.O.G Accumulation

Fat, Oil, and Grease—often called F.O.G—can solidify inside pipes. When these substances mix with calcium and water, they form huge, stubborn fatbergs.

This leads to major sewer clogs, with reports showing that half of all blockages happen in the United States and 40% in Australia.

Grease can come from various sources, including meat fats, lard, cooking oil, shortening, butter, and margarine. It also builds up from food scraps, baked goods, sauces, and dairy products.

Each year, the cost of fixing and maintaining sewer blockages is estimated to be around $25 billion in the United States and $100 million in Australia.

To address this issue, researchers have created a polyurethane coating enhanced with zinc.

This new coating helps by limiting the release of calcium from concrete, which is a major factor in fatberg formation. By reducing calcium, it makes it more difficult for fat, oil, and grease to build up.

They point out that this new coating is a promising and eco-friendly solution, as it reduces the release of calcium from concrete by up to 80% compared to uncoated concrete.

In this study, the researchers recreated harsh sewer conditions over a 30-day period. To speed up the fatberg formation, they increased the amount of fat, oil, and grease in the system, allowing them to test how well the coating would work under extreme circumstances.

30% reduction

Interestingly, the experiment showed that the new coating cut down FOG buildup by up to 30% compared to concrete without the coating.

Biplob Pramanik, Director of the Water: Effective Technologies and Tools (WETT) Research Centre at RMIT, explained that the reduction in fat, oil, and grease buildup is mainly due to the coated concrete releasing far less calcium. Additionally, the smooth coating surface prevents FOG from sticking as much as it does on rough, uncoated concrete. This was reported by InterestingEngineering.com.

Pramanik explained that traditional coatings, such as magnesium hydroxide, have been used for more than 20 years to control sewer corrosion. However, these coatings can unintentionally contribute to FOG buildup by reacting with fatty acids.

Pramanik explained that they took inspiration from nature, such as how human skin can heal itself. This idea helped guide the development of the self-repairing coating.

The team tested how well the coatings could repair themselves by creating small scratches on their surface.

"We noticed a clear improvement in the scratches after the healing process," explained Sachin Yadav, one of the researchers.

The new coating is both water-resistant and heat-resistant, capable of withstanding extremely high temperatures of up to 1,562 degrees Fahrenheit (850 degrees Celsius).

According to the press release, the researchers are working on an improved version of the coating. This new coating aims to better prevent FOG buildup by enhancing its ability to repair itself and making it stronger and more durable.

(The author of this article is a Defence, Aerospace & Political Analyst based in Bengaluru. He is also Director of ADD Engineering Components, India, Pvt. Ltd, a subsidiary of ADD Engineering GmbH, Germany. You can reach him at: girishlinganna@gmail.com) 

(Disclaimer: The views expressed above are the author's own and do not reflect those of DNA)