Supercritical UV technology for disinfecting liquids secures funding


Massey University engineer Professor Andy Shilton has invented a world-first method for UV liquid disinfection in a global market set to reach US$2.8 billion in 2020

Early prototype of the Supercritical UV system used for industry trials (Above)

A novel ultraviolet (UV) light technology for rapidly disinfecting liquids designed at Massey University has secured close to $300,000 in development funding to create a market-ready product. The Supercritical UV technology offers a new cost-effective solution for disinfecting low clarity liquids such as industrial effluent, juice, wine, and milk, which are difficult to treat due to their low UV transmissivity (UVT). 

UV is commercially used for wastewater treatment and in many food and beverage industries as an effective method of disinfection for pathogen removal and to increase shelf life due to its strong germicidal (inactivating) ability.

The patent protected Supercritical UV technology has been shown to offer a simple and effective disinfection capability in low UVT applications where standard UV technologies were not considered feasible.

Supercritical UV technology has the potential to capture a significant niche within the broader global UV disinfection equipment market, which is predicted to reach USD 2.8 billion next year, says Mark Cleaver, CEO of Massey Ventures, a fully owned subsidiary of Massey University which manages the University’s commercial investments.

“Supercritical UV technology enables UV light disinfection of previously difficult to treat, unclear liquids by maintaining superior light intensity across the liquid depth. This clever Massey University developed technology will allow a wider range of liquids to be effectively and cost-efficiently UV treated.”

The project has attracted $148,305 of funding from Pre-Seed investment provided by the Ministry of Business, Innovation and Employment (MBIE), with matching funding from Massey Ventures Ltd, to aid the full-scale technical refinement and commercial validation of Supercritical UV.  Massey Ventures will work closely with Massey University inventor Professor Andy Shilton and his team to provide commercialisation guidance and support for the project.


“This funding and support is really important as it will allow us to produce our first full-scale minimum viable product for trials at our early adopter partner sites. It will validate the commercial viability of providing efficient disinfection of low UVT liquids, and it will do so in an industrial environment” says Professor Andy Shilton, who has a PhD in Environmental Engineering and over 25 years of experience ranging from design/build of full scale pollution control systems to technology development for the water industry.

Current commercial UV equipment suppliers often cite the UVT should be greater than around 60% for their equipment to function effectively.  Lower UVT liquids can become expensive for traditional UV systems due to the increased costs to boost power input to achieve an adequate dose, and at a certain low point (around 30 to 40% even for systems that target lower than normal UVT liquids) they can become ‘out of range’. By contrast, Massey University trials conducted in industry have achieved excellent levels of disinfection in effluents with a UVT of 11% and lower.

Professor Shilton says that in the case of wastewater, “if the UVT is too low, it is often proposed to increase the level of physical/biological treatment prior to the UV system at massive additional expense. Alternatively, some industries simply adopt different methods to deal with disinfection which are significantly more costly than UV.”

Supercritical UV could also enable producers of animal supplements, milk products, juice, wine, etc to treat their products for enhanced shelf life far more cheaply than currently used methods such as pasteurisation. UV treatment has the added benefit of avoiding the impact that high temperatures have on nutritional value and flavour.

“Supercritical UV provides focused UV light input into a thin flow of liquid enabling far higher light intensity to be maintained across the liquid depth compared to existing technologies that apply the UV into much greater thicknesses of liquid”, says Professor Shilton. “Triggering high speed ‘supercritical’ flow maintains the high flow capacity despite the thin depth of the flow.”

The invention is the first application of UV light to supercritical flow for disinfection purposes.

“The ultimate goal is to have a locally manufactured Supercritical UV device on the domestic market in 2020, with the likely ‘beachhead market’ being industrial wastewater. International market development will follow successful local implementation via channel partners already operating in wastewater and other target markets,” says Cleaver.