Soft drink bottling is in a state of consolidation, with older plants closing and more efficient facilities picking up the slack. The U.S. has seen only a handful of greenfield projects involving soft drink plants in the last decade. PBV, the third largest anchor bottler in the Pepsi network, had an operation in Winston-Salem that had been expanded and modernized over the years, but its older plants were out of step with the times. In August 2001, construction began on a $40 million, 200,000 sq. ft. facility on 44 acres in suburban Raleigh, N.C., to replace those obsolete plants and jump-start the company’s entry into the bottled water business.
For example, PBV’s Winston-Salem plant has one clean-in-place (CIP) system to clean and backwash process lines between changeovers. At Garner, five CIPs service different areas. Beside the line system, a dual-tank CIP is dedicated to the syrup room, and three of the four fillers have their own CIP loops.
“There’s a lot of stainless steel in a CIP system, and that drives up the cost,” allows Jamison. Costs were minimized by integrating one filler’s CIP with an unusual vacuum de-aeration unit. Entrained air creates foaming with bottled water, and de-aeration solves the problem and allows faster fill speeds. The integrated systems also requires less floor space.
Water bottling drove the decision to create separate clean rooms for the plant’s four filling lines. With nothing to compete with any microbial organisms that might find their way into a bottle, plant designers opted to enclose each filler and equip it with a HEPA air filtration system that provides 40 complete air changes every hour. A typical soft drink filling room gets 5-10 changes an hour, Jamison estimates. Epoxy flooring and stainless steel wall panels enhance the sanitary design.
The fill-area workhorse is a 144-valve unit that can output 1,000 20 oz. PET bottles a minute. With a rotary rinser attached to it, the system measures 20 by 28 ft. The filler itself includes 36 capping heads. “With PET getting thinner and thinner, it’s like conveying a baggy down the line,” jokes Jamison. Liquid nitrogen dosing helps give the bottles rigidity and minimize downstream line jams.
Other fillers include a 1,600 per minute12 oz. can filler/seamer; a 1-, 2- and 3-liter PET line; and a bag-in-box line. But it is the single-serve PET line that poses the greatest operating challenge, and the bar keeps getting higher. A new 500 ml PET bottle with a profile that is as high as a 20 oz. unit despite holding 3.1 fewer ounces exemplifies the packaging diversity engineers must design their lines to handle. Jamison and two other engineers, including a former Anheuser-Bush electrical engineer, worked through those issues in house, coordinating closely with the Stahlman team and professionals at DSI Process Systems, St. Louis. Robert Ross, Stahlman’s on-site coordinator, quarterbacked those discussions, and the ability to modem auto-CAD drawings between all parties kept the project on track, something that would have been impossible in the days of hand-drawn designs, Robert L. Stahlman points out.
A floor-mounted air rotation system ventilates the packaging and warehouse areas and helps heat the plant during the winter months, eliminating the need for space heaters and other inefficient devices. Circulated air picks up heat from lights, motors, filling and packaging equipment and the mass of product being produced, greatly reducing the fuel demand to heat the plant during the winter. In a similar installation in New England, steam isn’t needed to augment the rotation system until February, Stahlman says.
Line jams put packaging compressors through their paces. Reciprocating compressors typically are used because of their ability to drop to 5 tons and then ramp up quickly to 200 tons of pressure after a jam has been cleared. Those units are not particularly efficient, however. PBV’s plant is outfitted with a combination of reciprocating and screw compressors, with the screw compressors carrying most of the load. “It becomes a control issue” to operate such a hybrid system, Stahlman explains. “Pepsi hadn’t used such a system before. We’d worked through those bugs in previous soft-drink projects.”
Numerous improvements and refinements were introduced during the project’s planning and implementation, adding up to a big step forward in plant efficiency. Superior sanitation systems, a refined packaging department and more precise processing procedures give PBV a state-of-the-art facility that should serve it well in the beverage battles ahead.
For more information:
Robert L. Stahlman, StahlmanEnginering Corp., 603-526-2585, email@example.com. Write in 417
Jack Leuchtefeld,DSI Process Systems, 314- 382-1525, firstname.lastname@example.org. Write in 418