Har Tuv, Israel-based Atlantium Technologies is seeing an uptick in interest for its proprietary technology that serves as a substitute for the energy-intensive heat pasteurization process.

During the past two years, the company worked with the dairy industry and U.S. regulators to win approval to use ultraviolet light to eliminate microbial contamination in water at dairy plants and processing sites.

The U.S. Food and Drug Administration recently gave its stamp of approval—an endorsement that Phyllis Posy, Atlantium’s vice president of strategic services and regulatory affairs, says could boost the market for UV purification of water across a number of industries.

“It’s not just a question of the dairy market. This is the first time UV has been put on the map with specific, clear and measurable criteria. I think this will make a big difference for the overall [UV] industry,” Posy told the Cleantech Group. “It helps people feel more comfortable with the use of UV for disinfection as an alternative to chemicals.”

Pasteurization is used to eliminate bacteria, making milk safe to drink. But the milk can be contaminated if the equipment and pipes that handle the milk are flushed with water that hasn’t been properly disinfected.

Typically, dairy plants use heat pasteurization to ensure the water is free of pathogens. But the technique has drawbacks, as pasteurization requires significant amounts of electricity and time. Chemicals such as chlorine can also be used for disinfection.

In both processes the water is stored in holding tanks, requiring the farm to calculate in advance how much water will be needed for the day. The flushing, which occurs when changing products, can be necessary multiple times per day.

“One side is the actual expenditures on heat and energy,” Posy said, estimating it takes 100 to 175 kilowatts an hour for heat pasteurization. “The other is operational inflexibility. If you plan to do product changes, you have to clean the equipment. You must stop everything to get the water ready.”

Atlantium developed Hydro Optic Disinfection, a technique that uses ultraviolet light to disinfect the water and provide pasteurized-equivalent quality. Atlantium says the process can supply water on-demand, allowing plants to change the water purification output according to the daily conditions.

“The nice thing about UV is that it’s as fast as the speed of light,” Posy said.

Compared with pasteurization’s requirement of 100 to 175 kW for an hour, UV disinfection requires 3 to 10 kW, she said.

The system funnels water past lamps, using fiberoptic principles to maximize disinfection in the water. The mercury lamps are outside the flow of water, and thus present no threat of contamination, Posy said. Atlantium says the system removes 99.999 percent of bugs in the water, which is a higher level of disinfection than necessary for some applications.

Installing the UV purification system can be capital intensive, but the costs can be recouped in about two years for most companies thanks to improvements in energy use and plant efficiency, Posy said, recalling one company that saw an ROI in six months because they were able to repurpose some equipment.

Atlantium assembles the components for the systems but does not manufacture the parts. The company is privately funded from Aurum Ventures, a holding company that manages the investments of Morris Kahn, and Elron Electronic Industries (Nasdaq:ELRN), which is a member of the IDB Holding Group. The company plans to seek additional funding to support expansion but has not set a target amount or timeframe, Posy said.

Atlantium has already installed its systems at dairy plants across the globe, including Israel, France, Italy, Australia and Russia. Because of continued investment in the water sector to solve its own shortages, Israel is expected to dominate the global water-technology market, exporting $2.5 billion in 2011 alone (see Israel to export $2.5B in water technologies by 2011).

The move into the U.S. market comes after the U.S. Food and Drug Administration recently finalized the 2009 Pasteurized Milk Ordinance. The PMO recommendations came from the industry group that governs Grade A milk, the biannual National Conference on Interstate Milk Shipments.

The FDA ruling represents the first time that the PMO provides criteria to use UV light to disinfect and pasteurize water for dairy plants. The 2009 PMO officially goes into effect in January 2010, but state regulators often follow the regulations as soon as they are published, Posy said.

“No one has been able to sell UV for this purpose [in the U.S.] ever before,” Posy said. “This enables a new, innovative technology that is more energy efficient and non-chemical.”

Atlantium has already installed systems at two U.S. dairy plants—United Dairy in Uniontown, Pa., and Galliker’s Dairy in Johnstown, Pa.—which worked with state regulators and third-party validators to get the necessary approval.

Since 2005, Atlantium has supplied its UV water purification system to the aquaculture, food and beverage, and municipal sectors. In aquaculture, UV is used to kill viruses without harming fish.

“In an Atlantium tank, the fishies are happy and live to be sold, and in the other tank the fishies are not there anymore,” Posy said.

UV adoption has somewhat been limited because it hasn’t traditionally been able to provide sufficient data, Posy said. What sets Hydro Optic Disinfection apart from other UV technologies is that Atlantium installed one sensor on the light, and another measuring the water quality.

“The fact that the technology is much more measurable makes a huge difference,” Posy said.