Go with low flow

By Dan Lemke

Wayzata, Minn. — NewBio, Inc. is making waves in the wastewater treatment world. The Wayzata-based company is designing, installing and managing anaerobic pre-treatment systems that are well suited to rural food processors.

Wastewater discharged from food processing plants often contains high levels of organic material, suspended solids, and fats and oils. The higher the concentration of these materials, the higher the surcharge a processor pays for municipal wastewater treatment. In some cases, overloaded municipal systems can’t handle the water, forcing businesses to truck it elsewhere or install pretreatment systems. The expense can be a big problem for small processors.

“Handling wastewater is a factor limiting the growth of agricultural processing in this country,” says Michael Gratz, NewBio president and CEO. “What we’re trying to do with our system is help small and medium-sized food processors solve a major problem. It is a very large market.”

High-strength waste

NewBio is currently targeting companies with low volumes of wastewater discharge — typically less than 250,000 gallons per day. Most of the nation’s 20,000 food and beverage processors are low-flow operators and can’t afford the custom-engineered water treatment systems designed for larger industrial operations.

“NewBio’s technology and its application are focused on companies with high-strength waste and low flow,” says Gregg Peterson, chief financial officer. “We want to treat the hot spots.” By segregating and capturing only the highest-strength waste for anaerobic treatment, NewBio saves processors money.

For example, a food processing line may require three washings. The first rinses away most of the solids and grease; that’s the water NewBio wants to treat. Water from subsequent washings contains less organic material and can often bypass treatment and be discharged to municipal systems at much lower rates.

95 above zero

Inside a NewBio anaerobic reactor, bacteria feed on organic material in the high-strength wastewater. “The reactor maintains optimal conditions for bacteria,” Gratz says. “We try to maintain conditions like it’s 95 degrees and sunny. Even during winter in Minnesota, we can sustain an ideal environment necessary for the high-rate anaerobic bacterial activity inside the reactor.”

Slurry inside the tank is stirred using NewBio’s patented fluidizing technology to keep solids and grease from forming a cap on top of the water. As bacteria consumes organic matter, they release methane, which is collected and either burned to provide reactor heat or flared off. Water passes through a sand filter before it’s discharged out the tank bottom to a municipal treatment plant or is blended with lower strength wastewater and subjected to further treatment.

The speed of organic breakdown depends on the waste’s strength and the volume of water, Peterson says. Most is treated in a matter of days, which holds down the system’s size and cost, making it affordable for processors with daily flows as low as 10,000 gallons, he says.

Pretreatment in practice

NewBio installed its first full-fledged system over a year ago at Minnesota Beef Industries in Buffalo Lake, Minn. Previously, Minnesota Beef had wastewater with very high organic matter, what wastewater engineers call BOD (biochemical oxygen demand), of 10,000 milligrams per liter, Peterson says. By comparison, household wastewater BOD is typically only 500 milligrams
per liter.

The NewBio reactor in Buffalo Lake is removing more than 90 percent of that material before discharging it for final treatment, thereby removing a significant constraint to Minnesota Beef’s expansion, Peterson says.

Full-fledged systems have been installed or are pending at other food and beverage plants in Minnesota, Oregon, Florida, Pennsylvania, Idaho and Michigan, Peterson adds.

AURI supported the development of a mobile pilot system, which NewBio has tested at a potato processing plant and a salad dressing manufacturer. Additional tests at a dairy plant and a dessert topping plant are being discussed.

Cost reduction is a significant marketing asset for NewBio. “One customer we’ve been talking with was ready to spend $3.2 million to build large treatment facilities at their two processing plants,” Gratz says. “Our smaller high-rate systems will save them over $2 million. That’s a significant amount of capital that they can turn around and invest.”

Gratz points to reduced federal funding for publicly owned treatment works and increased regulatory pressures as other key factors driving interest in industrial pretreatment systems. “Industrial dischargers basically want controllable and predictable costs for handling their wastewater,” he says.

“When they can adopt new technology that is both affordable and reliable, it makes sense for them to bring more of the treatment process in-house. Often their local municipality becomes a welcome partner.”

Long distance maintenance

NewBio is also utilizing computer and Internet technology to help market their anaerobic reactors. Since all major system controls and sensors are digitized, NewBio engineers can monitor and operate a system by computer almost anywhere in the world, saving personnel costs. Processors with remote systems “won’t have to employ a specialist in anaerobic treatment because our personnel can provide that … We often spot system management needs before our customers do,” Gratz says.

Gratz says long-distance monitoring also gives rural customers the same technical support as metro. “Since food processing often occurs close to the raw materials, we want to be able to work with companies in remote areas,” Gratz says.