Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers design system to improve disinfection of water used in food processing

27.02.2003


Georgia Institute of Technology researchers have developed a better-performing, less costly method of disinfecting water used in food processing.



Like current technologies, the new Advanced Disinfection Technology System relies on ultraviolet (UV) radiation to eliminate molds, viruses and bacteria. But the new system handles water more efficiently and thus improves the overall effectiveness of the disinfection process, researchers reported.

"We’re creating a mixing pattern to ensure that every particle of water is equally exposed to the (UV) lamp," said John Pierson, a senior research engineer at the Georgia Tech Research Institute and co-principal investigator. "By doing a better job of mixing the water, you get better disinfection."


Federal regulations require the disinfection of water used in food processing before it can be reused. In many cases, the lack of cost-effective disinfection means water is used only once and then discarded. When a disinfection system is used, the process is not always effective.

Most existing systems pump water through pipes lined with dozens of UV lamps. The lamps tend to foul quickly, reducing their effectiveness and requiring ongoing cleaning and replacement. More important, UV light has little penetrating power -- just about an inch -- so used water must be run through long pipes to increase the likelihood that UV light will contact enough of the liquid to affect the microorganisms it carries.

"Water right up against the lamp gets treated, and water farther away gets treated less -- or maybe not treated at all," explained Pierson, who is collaborating on the advanced disinfection system with Larry Forney, project director and an associate professor of chemical engineering at Georgia Tech.

The heart of the new advanced system is a pair of cylinders, one inside the other. The smaller cylinder rotates inside the stationary outer cylinder while water is pumped through the gap separating the two.

Inside the gap, the cylinder rotation causes water to churn and tumble in a well-documented phenomenon called a Taylor vortex. It’s actually a number of vortices, which mix water with light shining from four UV lamps embedded in the outside cylinder wall. UV light penetrates the water thoroughly, so no additional cycles through the system are necessary. Fewer UV lights are required compared to conventional systems, thus saving energy.

"Even if the fluid absorbs radiation, which would normally limit light penetration and thus the effectiveness of conventional UV reactors, the vortex motion in the new design continuously exposes fresh fluid to the radiation surface," Forney explained. "You bring the fluid in contact with just a few lamps in a repetitive basis."

The vortex motion also keeps the lamps free of material buildup.

The device is mechanically simple. Its low rate of revolution -- about one cycle per second -- means no bearings or special seals are required, Forney added.

The process was designed for recycling water from fruit and vegetable washing at food-processing plants, but it could be applied in other industrial processes.

"We think it could be useful for a number of water-treatment situations ranging from storm-water runoff to bottle washing to certain industrial-process water recycling applications," Pierson said. "It fits any application where you could use disinfected water rather than potable water, which would cut down on water use generally and conserve potable water in particular."

The disinfection process developed by Forney and Pierson may find uses far beyond the project’s original scope. Virtually anything that flows can run through the system, allowing for applications in the soft drink industry, brewing, dairy products and fruit juice processing. It would work for any kind of fluid for which there are concerns about the existence of pathogens, Forney explained. A non-thermal procedure, it could even supplant pasteurization, which is expensive, changes the taste and consumes a lot of energy, he added.

A variation of the device could even be developed for swimming pools as a non-chemical alternative to keeping water germ-free.

"If you were able to pass pool water through a UV reactor successfully, it would feel like normal water," Forney said. "It would have no taste and wouldn’t be irritating to your mouth, eyes and lungs."

Preliminary work with the new lab-scale UV disinfection device shows a reduction in the concentration of viable pathogens by a factor of more than 200, compared to existing technology with the same UV dosage, according to Carolyn Goodridge, a visiting postdoctoral fellow and member of the research team.

"We’re also beginning to work with certain kinds of fluids, such as fruit juices, that absorb lots of radiation to see what effect our device has on the inactivation of pathogens in that kind of environment," Forney added.



The research is sponsored by the state of Georgia through its Traditional Industries Program (TIP), a public-private partnership created by the General Assembly in 1994 to bring university-based research to bear on challenges faced by industry. TIP research and development for the food processing industry is coordinated through the Food Processing Advisory Council. In addition to the food processing industry, TIP also addresses industrywide issues in Georgia’s textile and carpet, and pulp and paper sectors.


For technical information, contact:
1. Larry Forney, School of Chemical Engineering, 404-894-2825 or larry.forney@che.gatech.edu
2. John Pierson, Georgia Tech Research Institute, 404-894-8059 or john.pierson@gtri.gatech.edu
3. Charles Estes, Economic Development and Technology Ventures, Georgia Tech, 404-894-6106 or charles.estes@edi.gatech.edu


Jane Sanders | EurekAlert!
Further information:
http://gtresearchnews.gatech.edu/

More articles from Process Engineering:

nachricht Harder 3D-printed tools – Researchers from Dresden introduce new process for hardmetal industry
11.10.2018 | Fraunhofer-Institut für Keramische Technologien und Systeme IKTS

nachricht Flying High with VCSEL Heating
04.10.2018 | Fraunhofer-Institut für Lasertechnik ILT

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Purdue cancer identity technology makes it easier to find a tumor's 'address'

16.11.2018 | Health and Medicine

Good preparation is half the digestion

16.11.2018 | Life Sciences

Microscope measures muscle weakness

16.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>