- THE MAGAZINE
- FOOD MASTER
Parmalat also used the occasion to install a new high-temperature, short-time pasteurization (HTST) system, and to replace the plant's hard-wired control system with a new Allen Bradley Programmable Logic Controller (PLC) and PC-based control system, according to John Miller, president of Seiberling Associates Inc. (SAI), Dublin, Ohio, the project's process/CIP engineer. The PLC controls all field devices from receiving to fillers via multiple distributed Input/Output (I/O) device drops while communicating to operators through Human Machine Interfaces (HMIs) in the plant's filler room, receiving room and newly constructed central control room.
The plant, which operates five days per week and receives raw milk seven days per week, produces a variety of pasteurized products, including skim milk, flavored milk, buttermilk and orange juice. Among other benefits, increasing the plant's capacity from 400,000 gallons of milk per week to 800,000 gallons per week enabled Parmalat to close a dairy operation in Columbus, Ga.
Parmalat maintained a flexible production schedule in order to keep the milk flowing. If construction-related downtime was required one week, additional production time was added the next. "Some weeks, employees who typically worked six days would work seven days instead. Then the following week they would only work five days, and we'd use the remaining two days to accomplish what we needed to," Rocheville said.
Miller, Carkner and Rocheville were especially vigilant during the installation of new equipment, "Contractors and vendors like doing the work, and they do do the work, but they don't always understand that the end result needs to be customer friendly," Rocheville observed.
"Plenty of surprises"Originally built in the 1950s, the plant had been subjected to numerous "wrongdoings" over the years, many of which only became apparent once engineering and construction crews began poking around. "We uncovered plenty of surprises," Rochville said. "If you don't have documentation, that's when the animal rears its head and bites you, and that's what happened here."
In one instance, project team members discovered preventive maintenance software that had never been properly installed. "Everyone wants preventive maintenance, but no one wants to treat it as a capital project," Rocheville said. "They treat it like a stepchild. We started playing with the software during the project -- we're still playing with it. And we're starting to see results."
Rocheville credits much of the project's success to teamwork among the project's designers, builders and vendors, many of whom had years of hands-on experience with complex projects. "People today tend to sit behind computers -- that's how they want to do their work," Rocheville said. "But you can't always do that. You also have to walk the plant. How else are you going to learn?"