Graton, California Selects Pasteurization Technology Group’s Chemical-Free Wastewater Disinfection System

San Leandro, California (EastBayDaily) — The northern California town of Graton has signed a contract with Pasteurization Technology Group (PTG) for the purchase and installation of PTG’s chemical-free wastewater disinfection system to handle all the city’s sewage treatment needs. By switching from a chlorine-based wastewater disinfection system to PTG’s safe, sustainable wastewater disinfection technology, Graton will realize significant operational savings and meet or exceed state water quality standards.

The innovative disinfection and cogeneration system is the linchpin of an $8.5 million project to update and upgrade the 36-year-old wastewater treatment plant, which serves the 1,700 residents of Graton. The new PTG X-500 wastewater disinfection system, which represents less than one tenth of the total project cost, can process up to 576,000 gallons per day—easily sufficient for Graton’s 1,700 residents. The system is planned for delivery in the spring of 2013, with project completion expected by January 2014.

Like many wastewater treatment facilities around the country, the Graton Community Sewer District is facing increasing wastewater treatment and energy costs. District management and Graton residents are also concerned about the potential harmful environmental impact of using chlorine to disinfect the town’s wastewater. The PTG system eliminates the need for toxic chemicals or costly UV lamps in the final stage of wastewater treatment. Instead, it uses pasteurization (the same process used to sanitize milk), raising the temperature of the wastewater to 180 degrees and disinfecting it. The result is a clear, clean, pathogen-free effluent that is pure enough for irrigation of food crops.

Robert Rawson, general manager of Graton’s wastewater treatment plant, says the PTG system is a good fit for a community that has long stressed the importance of putting the environment first. “The PTG system makes sense for Graton, the environment, and our ratepayers since it uses a natural and sustainable method to disinfect our wastewater, and delivers immediate payback. Power rates are projected to increase about seven percent every year for the foreseeable future, while natural gas costs are projected to stabilize or decrease,” Rawson said.

The system uses inexpensive natural gas to generate electricity, which will be used in the plant, plant offices, and associated buildings. The PTG system is expected to significantly reduce the District’s costs by generating electricity at half the cost of grid power. The District will also eliminate the costs associated with purchasing and storing chlorine (a toxic and hazardous greenhouse gas).

The technology has the blessing of both federal and state regulators. The technology was officially included in the U.S. EPA 2012 guidelines for water reuse. In its report, the EPA noted that PTG’s technology is a proven process for effective wastewater disinfection that has undergone rigorous testing, and that offers significant cost savings over other approaches by reducing energy consumption and eliminating the use of chemicals. It is also one of the few technologies to be certified by the state of California under its stringent Title 22 standards that regulate the disinfection of water for reuse.

“Our two-for-one approach, which uses waste heat from an electricity-generating turbine to disinfect wastewater, is a smart solution for any community that is committed to saving money and the environment,” said Greg Ryan, CEO and co-founder of PTG. “This contract with Graton is further evidence of our strong value proposition for municipalities, and a significant milestone for PTG. It marks our evolution from a water-technology startup to a revenue-stage company with a rapidly accelerating sales backlog. Word is spreading about the significant savings our technology generates in both wastewater treatment and energy, which is why we are seeing increasing demand from other cities as well as from food, beverage, and agricultural processing companies.”

PTG helps cities and businesses transform wastewater into a valuable resource

PTG is the first and only company in the world to combine wastewater disinfection with renewable-energy generation. PTG’s patented technology can use either the digester gas (often referred to as biogas, a natural by-product of wastewater treatment) or natural gas as fuel to drive a turbine or engine that generates renewable electricity. The hot exhaust air from the turbine or engine—energy that is typically wasted—is then passed through a series of customized heat exchangers that increase the temperature of the wastewater to a level that disinfects it. PTG’s technology is significantly more cost-effective and more energy-efficient than other methods. And, unlike other wastewater disinfection approaches, PTG’s systems do not require toxic chemicals (such as chlorine) or costly electrical power and expensive UV lamps.

About Pasteurization Technology Group California-based Pasteurization Technology Group (PTG) is a fast-growing, venture-capital backed company that is revolutionizing the disinfection of wastewater. PTG’s systems feature its patented “two-for-one” technology that combines eco-friendly wastewater disinfection with the generation of renewable energy. PTG’s process is one of only a handful of technologies to pass the stringent standards of Title 22 in the state of California for the disinfection of water for reuse. By channeling the typically wasted exhaust heat from a turbine or engine to disinfect wastewater, PTG’s process is able to deliver the most energy-efficient and lowest-cost solution on the market. PTG has won numerous awards including the 2012 Artemis Top 50 Water Tech award and the Popular Science 2011 “Best of What’s New” award. For more information, see, and follow @pastechgroup on Twitter and Facebook


Tim Cox
Pasteurization Technology Group

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