Making poultry wastewater community-friendly
Tyson Foods pretreats 3.8 million gallons of poultry wastewater a day at its Clean Water Award-winning chicken processing facility in Wilkesboro, N.C.
Tyson Foods’ poultry wastewater pretreatment plant coexists nicely on the main streets of Wilkesboro, North Carolina, where scenic history and tourism are integral in community life. So much so that the Tyson Foods Fresh Retail Division’s Wilkesboro complex was awarded the U.S. Poultry & Egg Association (USPOULTRY) 2014 Clean Water Award in recognition of exemplary performance pretreating its wastewater prior to discharge to a publicly owned treatment works (POTW).
Since the broiler complex is the majority of the city’s discharge, the poultry wastewater treatment used must achieve pollutant concentration at least comparable to what residential homes discharge to the city water reclamation works. This is impressive since the complex contains both a processing facility capable of handling 2 million broilers per week as well as a foodservice plant producing primarily fully cooked chicken products for restaurant and international customers. The broiler complex treats an average flow of 3.8 million gallons per day.
Poultry wastewater reclamation amid scenic foothills
The unique location of the poultry complex speaks to the importance of its water reclamation process. The town of Wilkesboro, nestled in the North Carolina Yadkin Valley foothills, relies on its scenic heritage and history to sustain tourism. That same legacy includes the Wilkesboro complex that is located squarely in a more heavily urbanized section of town. As a result, the building housing the initial wastewater treatment equipment sits adjacent to a main thoroughfare. Moreover, the final treatment processes and city POTW discharge into the Yadkin River and adjoin a campground that hosts an annual music festival drawing almost 100,000 attendees over four days.
Wastewater screening precedes DAF systems
The Tyson Wilkesboro complex employs primary screening followed by four chemically enhanced dissolved air flotation (DAF) systems. The treated water is then pumped over two miles to where it undergoes final treatment in two separate aerated lagoons. From there it is discharged to the adjacent city POTW. A dedicated plan and hardware upgrades are in place that enable both the city POTW and Tyson to support the other as needed in emergencies.
The solids recovered from the DAF [secondary protein or product nutrients (SPN)] are dewatered and then processed off-site. Management is looking at technologies that could allow additional on-site treatment of process solids to recover value-added by-products.
Water reuse at Tyson poultry facility
One central aspect of the poultry complex’s operation is the water reuse program. Here, 1.5 million gallons of process rinse water is captured, further cleaned and recycled back into various areas of the facility. Dedicated screening inside of the processing plant thus enables the facility to ultimately discharge 2.5 million gallons per day excluding the screened, recycle water, thus reducing water usage by 32 percent.
Stormwater prevention addresses water quality standards
Another challenge from operating in town is addressing stormwater runoff that potentially contains bacteria. A growing number of states like North Carolina have established specific benchmarks for pollutants that cause or contribute to an exceedance of a water quality standard. Benchmarks provide a way for industrial activities to monitor and adjust their stormwater pollution prevention plans. Benchmark exceedances can occur without a permit violation, although continued failure to achieve benchmarks may result in an individual permit being issued.
Tyson Wilkesboro has thus constructed trenches to divert stormwater to the complex wastewater treatment system from the live haul and dust collector areas. Related upgrades include the modification of two stormwater collection pits to catch runoff from the live sheds and receiving areas, providing additional detention for stormwater runoff that contacts live animal handling areas.
James Brown, facility environmental manager further notes that “a 60,000-gallon wet well is also in place to not only capture and detain the stormwater first flush, but also help equalize low-volume, high-concentration weekend flows that typically occur when the foodservice plant operates without the processing plant. We also noticed that the canopy areas around the complex truck service center attracted pigeons and other birds so we retrofitted the surfaces. Little details like that help us to reduce bacteria in our stormwater and our overall wastewater treatment performance.”
Tyson’s community involvement in Wilkesboro
The Tyson Wilkesboro complex is dedicated to its community schools and nonprofit programs. An effort led by the environmental team provides trash removal along a one-mile segment of an unnamed tributary. Those waters feed into a trout support stream where a free youth fishing day is conducted. Also, a trail head entry area is maintained by planting flowers, weeding, trimming shrubs and mulch addition.
“We focus on safety and making small but important changes in our process. A key to our success is communications, not only within the complex but also with the city,” states Brown. “If a process upset occurs, our management team is such that I am immediately called so that we can make process adjustments and get ahead of it. The same is in place between us and the city. It also helps to stay involved in the community we live and work in.”
The facility, throughout a history of different owners, has 50 years of poultry processing at its current site. Tyson Foods’ ability to successfully operate a large complex and wastewater treatment in an urban setting while successfully partnering with the city to discharge reclaimed water to a key community scenic and tourist area defines the Wilkesboro Complex as a 2014 Clean Water Award winner.