Chemical dosing tech to combat sulfide smell in sewers

Dr Jiuling Li from the Australian Centre for Water and Environmental Biotechnology at the University of Queensland (UQ) has developed an award-winning, real-time control and chemical dosing technology to combat hydrogen sulfide, reducing odour and corrosion in sewers.

“Hydrogen sulfide is also known as rotten egg gas — it is generated from sewage, smells bad and is a major cause of corrosion in critical and expensive wastewater pipes,” Li said.

“We have developed algorithms to predict when hydrogen sulfide will build up based on flow measurements in the system.

“That is integrated with real-time monitoring equipment and technology to calculate and inject a precise dose of control chemicals into the network.

“The end results are: the infrastructure will last longer, odours and toxins are kept out of the environment and chemical use is reduced because it is only added when needed,” Li said.

Li and Honorary Professor Zhiguo Yuan have received a Silver Project Innovation Award from the International Water Association for the development.

“We’ve been testing the real-time control system for chemical dosing in two sewer networks in Queensland — on the Gold Coast and in Brisbane’s western suburbs,” Li said.

“By improving dosing effectiveness and efficiency, we estimate the technology can reduce chemical use by around 40% in most dry weather scenarios.”

The solution for managing hydrogen sulfide in wastewater pipes has built on almost 20 years of work at UQ and the next step is to test it in larger systems and in other regions with different climates.

“Ultimately this technology could extend the service life of sewer infrastructures and reduce the need for frequent inspections and maintenance work in wastewater systems, all of which add to residential water bills,” Li said.

“Controlling corrosion and odour problems in sewer networks is critical for water management and also for protecting human health and the environment.”

The project is supported by the Australian Research Council, Urban Utilities, City of Gold Coast and SA Water.

Image credit: The University of Queensland