Fibre-optic sensor to warn of membrane fouling

A water-quality sensor for desalination plants, which uses fibre-optic nanotechnology, has been developed by researchers from the ECU Electron Science Research Institute at Edith Cowan University in Western Australia.

Funded by the National Centre of Excellence in Desalination Australia, institute director Professor Kamal Alameh and his team have created a sensor which they claim can identify potential membrane fouling in desalination plants.

Current sensor models are bulky, vulnerable to corrosion and typically require a power supply at each sensor node. The new fibre optic sensors offer a more accurate, robust level of monitoring for desalination plants, Alameh said.

“The fibre-optic sensors are the same thickness as a human hair. An optical fibre costs just Aus$ 7 (US$ 6.74) for a 1 km length. Our fibre-optic sensors provide real-time information, acting as a warning system to imminent fouling by monitoring salinity values as low as 5 mg/L,” said the professor.

“The sensors meet the required industry standard and can capture temperature, flow rate, pressure and salt passage,” he adds.

Alameh believes that the sensors could also be used in the oil and gas industry.

“The laser light guided within the optic fibre is a unique feature which the oil and gas sector could also use to sense the quality of oil at deep levels, or sense gases in very harsh environments,” he said.

His team has developed a fibre-optic sensor demonstrator and is currently investigating the potential to commercialise the technology with industry partners.