In 2010, the Wild Turkey plant in Lawrenceburg, Ky., had reached capacity. Its existing distillery needed to be expanded into a highly automated facility in order to meet demand for volumes. The Wild Turkey brand is owned by Campari Group, and this particular plant produces 20 whiskey flavor variations, including the limited-edition original bourbon recipe for which the brand is named.
The idea of a new production facility with more automation and control in the distillation process created some apprehension with operations and management. But the goal was clear: more efficient production without losing the bourbon flavor profiles.
“Years of success in the bourbon industry have shown that we have the taste part down,” says Jim Sanders, distillery production manager at Wild Turkey. The ultimate goal was to preserve that flavor while improving the process in an expanded facility, which meant arming our operators with tools that provide deeper insight into our distillation process.”
The Wild Turkey bourbon distillation process begins by grinding a mixture of corn and rye that is then cooked, cooled, and combined with barley malt in order to convert all starch into fermentable sugars. This mixture is then funneled into fermenters, where Wild Turkey adds its own homemade yeast.
After a few days, the new mixture, or mash, is ready to go through the still—a large, copper, silo-like structure. The fermented mash is pumped through the top of the still, while steam is pumped in from the bottom. When the steam meets the fermented mash, vaporized bourbon is produced. This vapor rises into a condenser, turning into liquid, while the solid grains float to the bottom (and are later repurposed for cattle feed).
After distillation, the bourbon flows into the cistern room where it is divided into new charred oak barrels and stored (aged) for six to 12 years.
From sequences to controlled procedures
For this greenfield project, Wild Turkey enlisted the help of Rockwell Automation (www.rockwellautomation.com/process) and system integrator Bachelor Controls, Inc. (www.bachelorcontrols.com), a Solution Partner in the Rockwell Automation Partner Network program. BCI implemented the control architecture for the new plant, which included Rockwell Automation’s PlantPax software platform, ControlLogix programmable automation controllers (PACs), FactoryTalk AssetCentre software, and EtherNet/IP and DeviceNet communication networks.
According to Wild Turkey, the new control system was to provide operators with as much production visibility as possible, and offer a cohesive control strategy in the many discrete steps of the distillation process, such as fermentation and evaporation.
With many bourbon flavor products and profiles to replicate, the Wild Turkey team meticulously provided BCI the sequential processes for all its recipes.
“Each portion of the process was broken down into multiple sets of sequences which were combined with recipes that contained not only quantity of ingredients, but temperature and flow rate setpoints,” says Marvin Coker, senior project engineer at BCI. It was then BCI’s task to convert these sequences to automatically controlled procedures.
The PlantPax control platform incorporated sequencing compliant with the ISA-88 set of standards, and terminology for batch control executed through Rockwell Automation’s Logix Batch and Sequence Manager. This functionality allows operators to configure recipes and formulas directly in the Rockwell Automation Allen-Bradley ControlLogix controllers through software, and remove any need for extra high-level programming of code when the controller must implement changes.
Controlling every batch
The highly nuanced process of making bourbon aligned nicely with Rockwell Automation’s PlantPAx Objects feature, which allows operators access to significant information about every loop. Coker adds, “We implemented a color-coding scheme on the line segments that indicated to the operator which material is currently in that line, and help trace flow paths and the product in that pipe at that particular time.”
The most challenging aspect to control in the distillation process is the cooking of the barley malt in order to convert all starch into fermentable sugars, says Coker, as it has the most variability.
“This process varies month-to-month and year-to-year, so the overriding concept of designing and implementing a control system for such an environment is to design methods to provide feedback of the current state of the process to the operators and management staff,” Coker explained.
Instrumentation at the new plant includes standard temperature and pressure sensors, as well as Coriolis flowmeters that measure “output density as proof” at certain sequences in the distillation process.
At the older Wild Turkey distillery in Lawrenceburg, seasoned operators relied heavily on their senses when producing bourbon, and BCI carried over this vital operational element for the new facility. The artisan component in bourbon production emphasizes smells, sounds of the process, and how the mash looks, smells and tastes. That means, with input from these operators, BCI placed the control room in the center of the new distillery, so operators could be in close proximity to the process and its smells.
This was quite noticeable during operator training for the new control platform. BCI stressed the operators’ “sense” instincts from the older distillery and translated them to the new control system via the information on the operator interfaces (HMIs). “It is essential with an existing process that the control system is seen merely as a set of new tools that allows operators to continue to apply their craft while hopefully using less of their energy to do so,” Coker says. “It should enable their artistry, not hinder them in applying their craft.”
After the integration was completed in 2010, Wild Turkey produced more than 10 million proof gallons in the new facility’s first year, doubling their five million proof gallons per year at the older facility.
“It’s been quite impressive to see how the time-honored traditions and new automation tools can co-exist so seamlessly, and work together to produce the same great tasting bourbon Wild Turkey customers have been enjoying for over a century,” says Sanders.