Digital Magazine

Printer responds to tougher environmental standards

New regulations nailed a solvent done considered environmentally friendly. Poly-Pak Industries scrambled to meet the new standards and combat a wave of negative publicity surrounding the company's use of the solvent.

Poly-Pak Industries faced a sensitive environmental problem in early 1993 at its manufacturing facility in Melville, NY.

At this facility, Poly-Pak prints corporate names, logos and graphic designs on polyethylene shopping bags. The final product, which is printed on flexographic plate-type printing presses, is delivered to such well-known major retailers as Gap Kids and the Limited.

For years, Poly-Pak met its air quality permit requirements, as well as its manufacturing and product-quality requirements by utilizing 1, 1, 1 Trichloroethane-(TCA) based inks.

US Environmental Protection Agency considered 1, 1, 1 TCA to be environmentally friendly because of its stability in the lower atmosphere. Unlike the emissions from volatile-organic-compound-based solvents, 1, 1, 1, TCA emissions seemingly didn't form ground-level ozone--smog.

Over the last few years the consensus on the risks of using 1, 1, 1, TCA has changed. Studies showing the toxicity of 1, 1, 1, TCA have ended its acceptance as an environmentally friendly solvent. It destroys the ozone in the stratosphere, much like CFCs. In fact, recent regulations have required the total phase-out of production of 1, 1, 1, TCA by Dec. 31, 1995.

Under Title VI of the Clean Air Act amendments of 1990, companies using 1, 1, 1, TCA after May 15, 1993, must prominently display warning labels on any products manufactured with the compound.

Vincent Trama, Poly-Pak's vice president for finance, figured the company had three options:

[] Continue to use 1, 1, 1 TCA and apply the required warning labels on its bags.

[] Switch to a waterborne system.

[] Switch to a volatile - organic- compound-based system and install appropriate pollution-control equipment.

As Poly-Pak examined its options, further detrimental factors with 1, 1, 1 TCA became apparent. "There was extensive damage to buildings and printing presses because of the formation of hydrochloric acid which created rust on our roof deck and caused serious corrosion to the presses.

"This, in turn, created a sharp increase in maintenance costs beyond acceptable levels," Trama said.

In addition, major manufacturers stopped producing 1, 1, 1 TCA, which created a shortage of the product, and sharply increased federal taxes to discourage further use.

To top off a growing list of problems, Newsday, a Long Island, NY, daily newspaper, broke a lead story on the area environment in January 1993. It cited Poly-Pak Industries as one of four top air polluters on Long Island and the leader in Suffolk County where the company is based.

Unfortunately, the story neglected to note Poly-Pak was actually in compliance with state and federal emission regulations at the time.

Trama commissioned a consulting firm with the expertise to study the problems involved with replacing 1, 1, 1 TCA, compliance with state and federal emission regulations, maintaining product quality, reducing maintenance costs, and maintaining crucial production schedules during changeover operations. This all had to be done within critically brief timeframes.

P-F Technical Services, Levittown, NY, was selected as the consulting firm with Fred Shapiro heading the team. After a thorough study, P-F Technical recommended that Poly-Pak use alcohol solvents and install a catalytic oxidizer to reduce emissions to acceptable levels and to maintain compliance under state and federal regulations.

Poly-Pak had previously experimented with waterborne solvents as a replacement for 1, 1, 1 TCA for about a year and a half without success. Fred Shapiro points out some of the problems encountered.

[] First, flexo presses have to be structurally altered to accept waterborne inks.

[] Second waterborne inks don't adhere well to polyethylene. They don't wet out properly and they tend to bead. Correcting this problem involves the addition of corona-treating equipment, which isn't compatible with all of PolyPak's presses.

[] Third, the use of waterborne inks requires the reworking of the ink train and the replacement of the anilox rolls preferably with ceramic to avoid rusting from the water. The many changes and adjustments would be very expensive and generally reduce productivity by approximately a third. "A changeover to waterborne inks would cost in the neighborhood of $500,000, not including expenses for downtime, retraining and a drop in productivity," Shapiro said.

Waterborne solvents were rejected as a replacement for 1, 1, 1 TCA because costs would be prohibitive, equipment couldn't be properly adapted to water inks, and quality and production would be reduced.

Solvent recovery was another possible alternative considered for Poly-Pak. Flexographic inks are usually made up of four to eight different solvents and require a combination of four or five additives to dilute the ink.

They also tend to attract water. A solvent-recovery system produces a blend of solvents. Some, or all, of which may not be usable. If it attracts a relatively small percentage of water, the recovered solvent will gel the ink when mixed with a fresh supply.

Further, it's an expensive process, and in a typical high-volume flexo operation, the system doesn't generate enough vapors to keep a recovery unit working effectively. For these reasons, the solvent-recovery system was rejected.

Carbon absorption, as a replacement for 1, 1, 1 TCA, presented a problem in the production of hazardous waste.

The use of this system results in the buildup of contaminated canisters which require removal and destruction. While carbon absorption is relatively practical for small operations it's simply not cost effective for a facility of PolyPak's size, and ends up trading one hazardous-waste problem for another.

Thermal incineration was given careful consideration by P-F Technical Services but rejected for four reasons. The first reason was the the high initial cost of installation.

Second was the cost of operation on a day-to-day basis. The very high temperatures, 14000F-18000F, increase fuel costs dramatically. The third was the size and weight of the system.

Finally, the very high temperatures involved with thermal incineration tend to produce high levels of NOx, which reacts with volatile-organic compounds to form udesirable smog.

Of the options considered, volatile-organic-compound solvents in tandem with a catalytic oxidation system offered the ideal solution in the elimination of 1, 1, 1 TCA from Poly-Pak's operation. The combination offered an assurance of product quality and relatively inexpensive capital investment. Also, reduced operating costs result from lower operational temperatures and the high durability of the catalyst selected.

In addition, catalytic oxidation is an environmentally friendly process reducing volatile-organic-compound emissions to water and carbon dioxide while holding NOx emissions to negligible levels.

In addition to recommending the volatile-organic-compound solvent and catalylic oxidation system, P-F recommended specific companies to bid on the construction, design and installation of the catalytic oxidizer.

Wolverine Corp., Merrimac, MA, received the approval for the Poly-Pak project.

The company was founded in the 1930s, primarily as a manufacturer of dryers and ovens for such firms as General Foods, Kellogg's, Nestles and Nabisco. In the late 1970s, Wolverine began to manufacture oxidizers, as an extension of its dryer technology.

Under the guidance of Chuck Martinson, general manager of the emission control division, Wolverine constructed the catalytic oxidizer at its facilities in Merrimac.

"We did our homework very carefully," said Martinson. "Vital to the equipment was a catalyst which was dependable, highly durable, effective, easily maintain", and within the budget parameters established for the project.

"Wolverine's engineering group selected Johnson Matthey Environmental Products Group, in Wayne, PA, to supply the catalyst because of their long and highly regarded experience in the field and their superior reputation for customer service."

Martinson said that Wolverine doesn't staff chemical engineers to research catalyst design or application, thus relying on vendors with the capability to answer questions and recommend the best-suited catalyst for a given project.

"We have never doubted Johnson Matthey's ability to give us those answers. We really are building a very high-quality piece of equipment, and we don't feel we can give our customers high-quality products without using high-quality vendors."

Wolverine designed a catalytic oxidizer utilizing Johnson Matthey's Concat oxidation catalyst.

The Concat catalyst achieves the required destruction efficiencies while reducing the catalyst volume and therefore the cost of the catalyst by a third. The cost of the catalyst can represent one sixth of the total cost of the catalytic oxidizer.

The unit constructed for Poly-Pak is 13-ft. wide x 12-ft. high x 27-ft. long and weighs 66,000 lb. Installed, it handles several roll-to-roll printing presses and several in-line bag machines all connected to the one catalytic oxidizer. The use of Johnson Matthey's Concat enabled Wolverine to construct the catalytic oxidizer in one piece.

It was transported by truck to PolyPak Industries over the road with special permits, traveling only during daylight, and was delivered on site in a day and a half.

Goodhart Sons Inc., Lancaster, PA Wolverine's installation contractor, was on-site at Poly-Pak to begin work approximately two weeks ahead of the delivery date for the catalytic oxidizer. Carefully drawn plans kept downtime and production interruptions to an absolute minimum.

From receipt of order, Wolverine shipped in about 14 weeks and the equipment was up and running in 17 weeks.

The installation contractor worked around Poly-Pak's production schedule sometimes at night or weekends when necessary. Total downtime for Poly-Pak was of very little consequence.

The initial FID test conducted by Wolverine recorded a 98.6% reduction of volatile-organic-compound emissions, probably more than sufficient to eliminate Poly-Pak from any newspaper s raking of major air polluters.

Final testing for compliance has just been completed and the results are being submitted to the state of New York for approval.

Poly-Pak expects to have passed their official compliance test without any problems.

Trama breathes a little easier these days, literally and figuratively. Trama said the switch to volatile-organic-compound solvents has "definitely improved our product," and the installation of a catalytic oxidizer will accumulate savings to permit a payback in two and a half years.

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