BACTERIA KILLERS

Finalists have a last chance to clinch the prize at a ‘pitch day’ later this month when the winner will be announced.

Brisbane-based Cloevis is one of them, having developed a way to tackle the twin problems of stench and corroding sewer pipes through a patented mix of chemicals to kill the bacteria that trigger the problems.

These bacteria turn dissolved sulphates in wastewater into hydrogen sulphide, which gives off a rotten egg smell and then into corrosive sulphuric acid.

Most water and municipal authorities around the world attempt to manage the hydrogen sulphide instead of killing the bacteria responsible.

Cloevis believes its patented chemical mix, integrated with a dosing optimisation software tool, will cut operating costs of water authorities by up to 50 per cent.

Authorities currently spend between 50 cents and $1.50 per resident each year on chemicals to prevent sewer corrosion and odours.

Lead researcher for Cloevis, Professor Zhiguo Yuan (pictured), is honoured to be shortlisted for the UQ Business School Enterprize Awards, which is now in its 11th year.

“The problem with sewers smelling and corroding has been a big problem for the water industry for the last 50 or more years, but there haven’t been any good solutions until now. The industry was really struggling because the sewers were corroding very quickly,” he says.

“Eight years ago our team was approached by Allconnex Water about whether we could offer our expertise to find a solution to the problem, so we spent about 12 months trying to understand the problem because we’d never done anything like this before – our expertise is in the area of water treatment and management.

“We found something interesting after 12 months and Allconnex were convinced we could find a solution if we continued, so we formed a partnership with UQ and also received a number of grants on the way to finding the solution.”

Professor Yuan has joined forces with UniQuest, the university’s commercialisation arm, to develop the concept.

“We’re keen to see the application of the knowledge and that’s why we’re working with Uniquest as we want to become commercial. Uniquest have developed a business plan, which we believe will achieve this,” he says.

The technology’s commercialisation is now being led by UniQuest’s commercialisation associate Dr Tony Keating. He says the researchers were looking at existing ways and found that it was ad hoc as to which chemicals are used and how much was used. They found there was significant ‘overdosing’.

“The researchers thought there was a way of doing it better. The Cloevis chemicals break down the cell walls of the bacteria and kill them. They are simple, inexpensive chemicals in good supply and by killing the bugs they stop the hydrogen sulphide from forming and causing a problem,” he says.

“The other advantage is that you don’t need as much of them. Dosing with these new chemicals would be every week or so, whereas current dosing is done 24 hours a day, seven days a week. This means substantial savings for authorities in their chemical costs.”

Sewer corrosion is a major headache for water authorities, with frequent reports of sinkholes appearing after leakages and collapse of pipes. Cloevis’s chemical mix will be integrated with SeweX, a software tool developed by AWMC since 2003, which predicts sulphide formation and transfer in the sewer network, allowing authorities to optimise their chemical dosing regimens.

The SeweX model has been used by five Australian water utilities in corrosion and odour management in their sewers, with the Gold Coast reporting generated savings of $1.3 million.

Following successful laboratory and preliminary field trials of the Cloevis chemical mix, discussions are now underway to run commercial-scale field trials.

The UQ business school enterprize 2011 finalists were chosen from a record number of entries received for the competition. The four other finalists are Captain Therapeutics, HaystackHQ, AquaHydrex and Kaggle.