Emission Reduction in Waterless Printing Operations
Cup/food container manufacturer reduces VOC emissions and saves money with alternative cleaning
product used in their waterless offset printing division.
Related Products/Industry: Waterless Offset Printing on beverage cans, cup/food
containers, plastic pails, etc.
WinCup, Inc. is a foam cup and food container manufacturing company with
manufacturing plants located throughout the U.S. Their manufacturing process includes
printing logos and other graphics onto pre-formed styrofoam cups and other food containers
through a waterless offset printing process (other wise known as "dry offset").
| Problem: |
WinCup, Inc had been using isopropyl alcohol (IPA) to clean ink and
related soil off their printing equipment after a job was run. Isopropyl alcohol is
considered a VOC emission source by EPA and is a flammable substance with a flash point of
54 F. Flammable materials are subject to stringent storage and handling rules,
additionally the user may be limited to the amount they can store on site at any one time.
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| Goal: |
Due to increasing air emission regulatory limitations, and concerns about
worker safety due to the use of a flammable cleaning product; WinCup wanted to identify an
alternative cleaning product that worked just as well as the IPA at removing ink and other
residues from the printing presses and related parts, yet met their VOC emissions
reduction goals |
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| Course of Action: |
The company began working with a supplier who was familiar with the
printing industry and distributes their products to gravure, flexographic and offset
printers. The supplier began by talking with top management officials to get an
understanding of their business and then began working with production personnel to
develop an understanding of any special needs and concerns regarding their printing
process and application of the current cleaning solvent. This helped the supplier make
recommendations that would best fit the needs of top management, reducing VOC without
significantly increasing costs; and the needs of production personnel, which was to avoid
sacrificing cleaning performance or significantly increasing work. Based on this
information their supplier recommended several different products, each with varying
performance estimates and costs. The company decided to test Danko Industries' Wash-Up
Evap A, which appeared to be best suited for their specific application. Wash-Up Evap A is
100% VOC (based on method 24 analysis), but has a vapor pressure of 8.3 mm Hg @ 68 F (20
C)and a flash point of 143 F. Materials with a high VOC content (100%) and a vapor
pressure less than 10 mm Hg @ 20 C are equivalent to a VOC content of 30% by weight.
The new product required a slightly modified application procedure. The product is
applied by moistening a towel with Wash-up Evap A, wiping down the soiled parts, followed
by wiping it down a second time with a dry towel. Representatives of Danko came to
WinCup's facility and trained their press crew on how to properly apply the product for
maximum performance, then the employees were allowed to use the product on their own for
four weeks. During the test period Danko representatives regularly contacted management
and production personnel to answer any questions or discuss any problems associated with
performance and application of the product.
After the four week test period Danko representatives returned to the facility to
discuss continued use of their product. Based on product performance the entire company
was very pleased, but the cost of the product was significantly greater than the isopropyl
alcohol. The supplier was able to show that although the price per gallon of the Wash-Up
Evap A was significantly more than the isopropyl alcohol, the company would actually save
money because they would use much less product. As a result the company decided to begin
using the Wash-Up Evap A in their West Chicago, Illinois facility. If the supplier's cost
savings estimates proved to be accurate, then the company would consider using the same
product in other plants. |
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| Result: |
Based on the 1997 purchase records for the West Chicago, IL plant, WinCup
was using approximately 8633 lbs per year of isopropyl alcohol. This generated
approximately 4.32 tons of VOC emissions per year. Due to air emissions permit limitations
WinCup was forced to limit their production and cleaning activities while using IPA. By
switching to Wash-up Evap A the company was able to reduce VOC emissions from press
cleaning activities by 66% (approximately 2.85 tons VOC) and improve worker safety. This
reduction also created an opportunity to increase production without concern of exceeding
their air emission permit limits. WinCup estimates they have been able to produce 550 lbs
more material for every 1 gallon of IPA they eliminated (based on emission factor). The
clean-up waste from the Wash-Up Evap A is not considered a hazardous because it does not
meet U.S. EPA's or Illinois EPA's’ definition of a hazardous waste. Even though it is
not subject to considerable regulation and high cost of disposal as compared to hazardous
waste streams it cannot be discharged into the sanitary sewer. In Illinois the waste must
be manifested and disposed of as a non-hazardous special waste. Each state's waste
disposal regulations differ slightly and their regulations should be reviewed to determine
how the waste must be disposed of.
WinCup is now beginning to use Wash-Up Evap A at their Stone Mountain, Georgia and
Phoenix, Arizona plants, while their California and New Jersey plants are currently
testing/reviewing the product. |
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