When you sip a perfectly sweetened soft drink or sprinkle a no-calorie sweetener in your tea, you may have just enjoyed the fruit – or the kernel – of one British company’s labors. The company provides sweeteners, starches and other ingredients to food, beverage and other industries worldwide.
The company’s corn wet-milling process uses every part of the corn kernel to create byproducts, from animal feed to high-fructose corn syrups. But extracting sugar from corn kernels – the sweet spot for one of the company’s plants in the U.S. Midwest – requires a complex series of steps. And that multiplies the need for efficiency and flexible controls.
Outdated DCS, Lacks Efficiency
The ingredient producer acquired the Midwestern plant during a business acquisition more than 20 years ago. While the plant’s end products evolved to reflect changing consumer tastes and trends, its original process control system did not change and was showing its age.
“Runtime failures were steadily increasing,” said a principal process control engineer for the company. “At the rate we were going, we could not guarantee acceptable plant uptime in five or six years.”
When control components failed, it was increasingly difficult and expensive to locate replacement parts, putting plant productivity in jeopardy. The risk came to light a few years ago when a membrane filter on a skid line failed, forcing the entire production line to shut down.
Operators also had to rely on single-screen stations that lacked visualization capabilities, making timely troubleshooting nearly impossible. Without visibility into system devices, programmers needed to identify the programmable logic controller (PLC) code in order to identify a failed device.
“Anytime an I/O point failed, we had to shut down the entire production line because we had no easy way of identifying the problem, and it wasn’t worth the risk of running blindly,” the engineer said.
The plant’s reliance on obsolete parts – and the system’s inability to easily pinpoint problems – made it clear that the site urgently needed a new process control system.