New invention cleans up greenhouse gases

University of Auckland Professor Saeid Baroutian and the company he co-founded, Gaiatech, have invented a device that removes almost 100 percent of anaesthetic gases released during surgery.

In a hospital with 15 operating theatres, annual anaesthetic gas emissions are roughly equivalent to driving two million kilometres in a petrol car, he says.

“Anaesthetic gases have the largest environmental impact in hospitals.

“They are similar to chlorofluorocarbons – CFCs - and their greenhouse gas impact is thousands of times worse than carbon dioxide,” says Baroutian, a Professor of Chemical and Materials Engineering and a founding director of the University’s Centre for Climate, Biodiversity and Society, Ngā Ara Whetū.

After the device captures the gases, they are safely destroyed - and can even be turned into new products, such as calcium fluoride and other fluoride salts. Calcium fluoride is a key component of hydrofluoric acid, which is used in aluminium processing, glass etching and plastic manufacturing, he says.

Earlier this year, Gaiatech started a proof-of-concept hospital trial of the gas-capturing device, in partnership with Southern Cross Auckland Surgical Centre.

The first phase of the trial has just concluded, demonstrating the device works successfully to capture anaesthetic gases during mock surgeries in a hospital setting.

Baroutian says the team hasn’t had time yet to celebrate their success after eight years developing the device, but they will.

The next step is to use the device during real surgeries at Southern Cross Auckland Surgical Centre. 

When the trial is successfully completed, the device will be available to Southern Cross Healthcare hospitals and other hospitals in New Zealand.

“Our vision is that, over time, this becomes standard infrastructure in operating theatres, just like suction or oxygen.

“Eventually, this device could be used throughout New Zealand and internationally, cutting thousands of tonnes of greenhouse gas emissions at the source,” says Baroutian.

He is co-founder of another cleantech company, Nurox Hydrothermal, which has designed and engineered advanced hydrothermal technology that safely destroys medical and hazardous waste.

“We use hot, pressurised water and compressed air or oxygen gas, in a process that works like a fancy pressure cooker.

“It’s far cleaner than incinerating waste or dumping it in landfills.

“This new technology will help industries reduce their environmental impact and could also unlock the value of recoverable materials,” he says.

Nurox, in partnership with Tennex and Interwaste, has started to design and build two commercial plants to process healthcare waste.

The first is scheduled to open in Auckland in 2026, while the second plant is due to open soon after.

The Kiwi team started looking at ways to tackle medical and hazardous waste, because current systems are not environmentally sustainable, Baroutian says.

“New Zealand currently ships tonnes of hazardous waste offshore, where it is incinerated, creating environmental risks and high costs.”