Case Study

Food manufacturer converts wastewater into a sustainable resource

Flottweg's separation technology used at JTM Food Group.
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Managing Editor, ProFood World
JTM Food Group uses a three-phase centrifuge system that yields reduced wastewater volume and substantial savings.

Sustainability has long been top of mind for JTM Food Group. From reducing its packaging to employing geothermal refrigeration to lower electricity usage, the Harrison, Ohio-based food processor has spent the past decade stepping up its commitment to environmental responsibility. Its most recent green endeavor involves upgrading its wastewater treatment process with a three-phase centrifuge system that has minimized JTM’s environmental impact with reduced wastewater volume and yielded substantial cost savings. 

Committing to sustainability is a tall order for a growing company like JTM, which makes and distributes a variety of meat products, baked goods, frozen goods and ready-to-eat meals to thousands of schools, restaurants, military and government organizations, food distributors and retailers nationally. The plant features three processing lines: a grind and form operation for its hamburger patties, meatballs, steak hoagies and pork sausage patties; a kettle cooking operation with two lines for products such as chili, taco fillings, Sloppy Joes and spaghetti sauce with meat; and a bakery. Last year the company completed a $26.1 million, 190,000-sq-ft expansion of its Harrison plant, which JTM says will double its manufacturing capacity to 185 million lb of kettle-cooked food a year. 

Separation process

To help keep up with its growth in a sustainable way, JTM installed the Tricanter from Flottweg to process all its wastewater. This three-phase centrifuge system simultaneously separates wastewater into three components (grease, water and solids) that JTM can dispose of or reuse cost-effectively and sustainably. 

JTM processes about 35,000 gal of wastewater per day using the Tricanter. Wastewater is fed through a stationary pipe into the horizontal, solid-bowl centrifuge unit’s feed zone located in the center of the scroll. The bowl and scroll rotate in the same direction, but at slightly different speeds. As the bowl rotates, the solids in the wastewater are packed against the bowl wall by centrifugal force. The scroll conveys the separated solids toward the conical end of the bowl, where they fall through the discharge chute. The clarified liquids flow to the opposite cylindrical end of the bowl. The Tricanter discharges the heavy liquid (water) under pressure, while the light liquid (grease) is ejected through a port at the bottom of the unit aided by gravity. An adjustable impeller sets the separation quality of the two liquid phases. 

By separating the wastewater’s two immiscible liquid phases from the solid phase in one step, the Tricanter has allowed JTM to achieve a purer fat content, cleaner water and dryer solids from its wastewater — helping the company reduce its environmental footprint, save on costs associated with the further treatment of its wastewater and optimize production.  

Prior to installing the Tricanter, JTM used a vertical-stack, two-phase centrifuge system to treat its wastewater. While the equipment separated the solids from the liquid, it did not adequately separate the two liquids. The water still had grease in it, and most of the solids were still wet. As a result, JTM had to haul away the liquid and solids to a wastewater treatment facility for further processing, which is more expensive than disposing of them at a landfill.

“The old [centrifuge] was the wrong design because it in itself created a waste stream,” explains Jerry Cramer, a consultant with STS Process Technology, which oversees all the water requirements for the JTM manufacturing facility. “That waste stream was a mixture of solids and water, and it was of a sufficient volume that it was expensive to dispose of because it couldn’t be sent out to the landfill. It was too [much] liquid. It had to be hauled off as wastewater.”

Waste not, want not

By using the Tricanter, JTM now yields dryer solids that it can haul off to the local landfill — a much cheaper option than disposing of wet solids at a wastewater treatment facility. “The cost of putting it in a landfill is only 10 percent of the cost of disposing of it as a liquid,” Cramer explains. “So part of the justification for buying the Tricanter is the savings that we accomplish by not hauling the water off as wastewater and allowing the remaining wastewater to be clean enough then to send to the city processing plant.”

In addition, the Tricanter has delivered another source of revenue for JTM. The company sells the grease that the Tricanter extracts from the wastewater to local farmers, who use the tallow as chicken feed additive. “It’s a higher quality grease than we were getting out of the vertical stack,” Cramer says. “And a higher quality grease demands higher cost or higher revenue.”

According to Cramer, JTM has reaped a 25 percent savings overall by using the Tricanter to treat its wastewater. In addition to creating dryer solids as well as high-quality tallow JTM can sell, the Tricanter has produced a cleaner effluent that it can discharge back into the environment and reuse in its production process rather than trucking it off to a wastewater treatment facility for further treatment. “We probably save 10,000 gallons a week, which is about two truckloads,” Cramer says.

Cramer also credits the Tricanter for ensuring production moves along smoothly and continuously. When JTM previously used the vertical-stack, two-phase centrifuge, it hindered the manufacturing process upstream. Workers regularly stopped the centrifuge and blasted air and water in and between the plates to shoot out the solids that accumulated there, which blocked the flow of water. That sometimes created a bottleneck in the manufacturing process upstream. 

“Every five minutes it stopped [due to the buildup of solids] and then came back online. When it did that, it created a back-up flow of production water coming into the tanks to be processed,” Cramer says. “The tanks were too small, for one. And then the more frequently we [stopped] the centrifuge [to remove the solid buildup], the less water would be processed out of the tank. If you do that, then the water coming in exceeds the water going out, so the tanks overflow.

“So they would have to run up back upstairs and say, ‘Hey turn the water off. I can’t handle any more.’ Well if they turn the water off, then that backs up production,” he adds. “So even though this is not a production piece of equipment, it’s affecting production.”

With the Tricanter in place, JTM processes about 20 gal of wastewater per min during a 40-hour production cycle without any stops or starts. “Centrifuges work best when they run continuously with little change,” Cramer says. 

JTM has been so impressed with the benefits of the Tricanter that it plans to install an ultrafilter to further reduce the biological oxygen demand in the water. By doing so, JTM will be able to discard or reuse more water as effluent and make fewer trips to the local wastewater facility. JTM also intends to add automation to the Tricanter, which is operated manually now.

“We’re still in the process of fine-tuning the Tricanter, but it has proved itself,” Cramer says. “Now what we’re trying to do is to fine-tune it so we can make it operate more consistently at a higher level.”

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