Compressed Air Systems / Energy Management

Packaging producer upgrades energy infrastructure with four-stage compression system

In this installment of What Works, one company shows its commitment to continuous improvement of operational efficiency.

By Barbara Quinn, Contributing Editor

With 13 facilities throughout North and South America, Plastipak Packaging Inc., a leading manufacturer of plastic containers to the food, beverage and consumer products industries, is committed to continuous improvement of operational efficiency.

For its East Longmeadow, Mass. facility, that has translated into upgrading the energy infrastructure. Working with the company's energy supplier, Massachusetts Electric, Plastipak investigated a number of options, including cogeneration. In the end, it decided to purchase Atlas Copco's PETPACK compressors, which feature a unique four-stage compression system.

Specifically designed to address the needs of polyethylene terephthalate packaging producers, PETPACK uses oil-free screw and piston technologies,the first two compression stages are rotary, while the last two are piston. This combination provides for more effective intercooling and reduced discharge temperatures.

Paul Rowlands, Atlas Copco's business manager for oil-free compresssors, explained the technology this way. "Basically, you can halve your maintenance costs for three main reasons. First, the technology matches the airflow with air requirements; second, it softens the edges, because there are no sudden startups and turnoffs; and third, it allows production to change very quickly without changing machinery. We know the energy savings are approximately 20 to 30 percent,but we haven't yet calculated the savings related to reduced maintenance and extended lifespans."

New four-stage compressors have helped Plasticpak Packaging Inc. reduce its energy costs by 40 percent.

For Plastipak, some of the proof is already firmly in hand. The compressors generate a 49 to 50 Kw savings every hour, 24 hours a day. As a result, the company has reduced its energy costs by approximately 40 percent. "In energy savings, that's $80,000 to $100,000 annually per machine," says Shane London, conversion manager, facility and engineering manager, Plastipak. "I knew the four-stage would offer more energy savings, I just didn't realize how much." To date, annual wear on the machines is at 25 percent of what the company expected, while maintenance costs are at 20 percent of expectations. Other benefits include $90,000 in rebates from Massachusetts Electric. The utility also purchased Plastipak's existing 3-stage compressors.

Rowlands sees growing interest in PETPACK compressors. "In some parts of the country, there are still grid constraints or energy supply issues," says Rowlands. "We believe that any company interested in reducing its energy consumption and improving its compressed-air system will want to consider the PETPACK."