Lithography
Lithography dominates the U.S. printing industry, accounting for as much as 50 percent
of all conventionally printed materials. Approximately 85 percent of these printers employ
fewer than 20 people. There are two types of lithographic printing: sheetfed and web.
Sheetfed presses run individual sheets of paper through the press, while web presses feed
paper continuously from a large roll and can use either heatset or nonheatset inks. Once
the image is printed onto the substrate, the paper is either fed back onto a roll or cut
and/or trimmed into specific shapes and sizes. Web lithography is designed to print large
jobs and is used for newspapers, books, catalogs, periodicals, advertising and business
forms. Sheetfed lithography is used mostly for short runs of books, periodicals, posters,
advertising flyers, brochures, greeting cards, packaging and fine art reproduction.
Preventing pollution at the source may be achievable at each production step used in
lithographic printing. To begin evaluating and implementing pollution prevention
opportunities within the printing process, principal input materials and processes need to
be outlined. The principal materials used in lithographic printing are inks and paper
substrates (Figure 6). Additional input materials are photographic films, photoprocessing
chemicals (developers, fixers, wash baths, reducers and intensifiers), printing plates,
plate processing chemicals, fountain solutions, cleaning solvents, correction fluids, rags
and water.
The lithographic process can be divided into four major steps: prepress, makeready,
press, and post press. Prepress operations involve a series of steps for which artwork or
design for the printed image is converted onto an image carrier--the printing plate.
During this step raw materials such as photoprocessing chemicals and solutions are used.
This process continues to change as digital prepress, with computer transfer of digitized
images, replaces much of the photographic process and related wastes.
Makeready are the steps taken to prepare the press to print. This involves attaching
printing plates to the press; adding ink and fountain solutions to each print unit;
testing the press to make sure the image is aligned properly (registration); and, printing
according to customer specifications. While essential, paper, inks, and solvents used
during makeready are basically all waste. Anything done to reduce makeready saves time,
money and reduces waste.
The press step is the actual printing operation in which inks, cleaning solvents and
substrates are used (Figure 7).
Postpress involves any finishing work performed to the printed product. This includes
any cutting, trimming, binding by gluing or stitching, and final packaging. This step may
use large amounts of binding and/or tape and adhesives when producing books, directories,
and pads. A specific look at each step in lithographic printing process follows.
Prepress includes all the steps involved in getting the printing plates ready to be
mounted on the press. In the image processing step, the material to be printed, whether a
"camera-ready" paper copy or an electronic version, is converted to film images.
Pollution prevention for this step involves techniques and technologies used in photo
processing operations. Wastes generated from image processing include empty containers,
used film packages, used film, outdated materials and chemicals, spent fixer solution
containing silver, spent developer solution, and waste rinse waters. Color separations for
the four primary colors (yellow, magenta, cyan and black) are also done in the prepress
stage.
Most printing operations begin with artwork and/or text. The "camera-ready"
is the final copy of the materials from which the printer will make the film used to image
the printing plates. Prior to the use of electronic desktop publishing, these
camera-readies involved gluing or waxing the back of the art and text to another sheet of
paper. This board was then photographed. If any errors were detected after this step, the
board would be corrected and re-shot. This process is still in use, but is being replaced
by electronic imaging.
Electronic imaging allows text to be edited and digitally manipulated on a computer
screen to also reduce waste generation in the prepress stage. The image is scanned or
created with digital cameras. The cameras digitize the image and then send it to a
computer for editing. After correction, the master copy is saved to a disk file. Color
separations can also be prepared electronically. This reduces or eliminates the need to
photograph, edit, re-shoot, and repeat photo processing. The advantage is the elimination
of a labor intensive and time intensive process involved in the manual layout and color
separation for the film. Once the film has been developed and proofed (checked for
accuracy) it is sent to the plate making operation.
As previously noted, lithographic printing employs photography for the reproduction of
artwork and/or copy. The materials used include paper, plastic film or emulsion. Emulsions
are usually composed of silver halide salts, including silver chloride, silver bromide,
and silver iodide.
One of the major areas for waste reduction in the printing process focuses on
photographic chemistry management. The three separate processes of photo processing
include developing, fixing, and washing. Many methods exist to better manage the raw
materials used, reclaim valuable raw materials from the process such as silver, and to
extend the life of the chemical baths. Additional help for assisting printers in reducing
waste in their photo processing labs can be obtained from vendors. New prepress processes
are regularly being brought to the market. Some printers are installing automated
recirculating silver recovery (fixer), water recovery and chemical replenishment systems.
Proofs are made from the film produced in the initial photo processing step described
above, to compare the press image to the customer approved artwork and act as a final
check prior to making the printing plates. The proof will show whether all images are in
line (registered), whether the color is right, and how the final printed image will
appear. Most proofing is now done electronically. All major prepress manufacturers produce
proofing systems that come in solvent and the newer aqueous-based models. Proofs are made
because the platemaking step will affect tone reproduction. Proofs are also used to check
camera and scanner separations and correction in color printing.
There are a number of different type plates used in lithographic printing:
photomechanical, electrostatic, bimetallic, relief, paper, and polymer plates.
Photomechanical surface plates are most common. They are made from thin anodized or
grained aluminum coated with a light-sensitive material. The most common plate coatings
are diazo compounds and photopolymer resins, although asphalt, shellac, gum arabic, and
polyvinyl alcohol are also used. An image transparency is placed over the sensitized
plate. Then a framed glass sheet is placed over the transparency and a vacuum is applied
to pull them tightly together. The plate is exposed to ultraviolet light, which passes
through the transparency and hardens the coating on the plate to make it insoluble to
water or other solvents (Jendrucko, 1995).
The next step in the platemaking process is developing. Plates can be additive or
subtractive. Additive plates are developed using a one step emulsion developer that
contains an oleophilic resin. This is used to make the hardened image areas receptive to
ink. Subtractive plates usually have an oleophilic resin included in the coating or
applied over the coating as a lacquer. When the plate is placed in the developer solution,
the non-coated image area dissolves. The image carrying plates accept ink from a roller
and transfer this image to a rubber blanket. The blanket, in turn, transfers the image to
the substrate-thus, offset printing.
Electrostatic plates are non-metallic paper plates and are made using the same process
as making office copies. The plate is coated with a photoconductor, which is ionized by an
electrophotographic camera. The charged paper is exposed to the reflection of light from
the image or copy to be reproduced. The white areas of the image reflect light to the
plate, which causes a dissipation of the charge on the image areas. The dark areas of the
image absorb light, which causes the electrostatic charge to remain on these areas of the
plate. Toner, which is attracted to the charged areas, is applied to the plates and forms
a visible image. During press operation, the toner attracts ink and the white areas are
water receptive (Jendrucko, 1995).
Photomechanical plate making is the most common method used in lithography. The plates
are coated with a photosensitive emulsion that changes chemical properties after being
exposed to light. The exposed area hardens, becoming hydrophobic repelling the water-based
fountain solution and being receptive to ink.
After the photographic emulsion has been exposed it must be developed. In developing
the plate, the unexposed areas are hydrophilic (attracts water in the fountain solution)
and become water receptive but repel the oil-based ink.
Printers should work closely with chemical vendors and ask them to supply nonhazardous
materials and inform them about any new products that are less toxic to replace currently
used materials.
One of the recent technologies used in lithographic printing includes moving away from
solvent-based plate developing systems. Switching to aqueous developed plates causes
little disruption to the plate processing system or printing operations (Kasper, date
unknown). Optimum performance is achieved by keeping the liquid volumes up to the
recommended level and closely monitoring the developer. The price these systems are
similar to other high-quality plates, and chemistry costs are less because there is only
one developing chemistry and no replenisher. Glass marbles can be used to bring liquid
levels of process chemicals to the brim each time the liquid is used, which extends the
chemical's life by minimizing contact with oxygen (Price, 1994). This technique can also
be used for film developing chemicals.
Plastic or photopolymer and electrostatic plates are all alternative plate types.
Information on alternative plate materials can be obtained from printing trade
associations as well as vendors. Changing to a computer-to-press print environment may
eliminate the need for plate chemistry totally, but this technology is currently expensive
and may not be applicable to all types of printing.
During makeready, printing plates are attached to the cylinder. Printing occurs when
the plate rotates so that the non-image areas can be treated with an ink-repelling
fountain/dampening solution. The plate is then coated with the ink, which adheres to areas
of the plate that contain the image. As the cylinder rotates, the image is transferred to
the substrate via the impression or blanket cylinder. The press is then fine-tuned to
ensure registration and ink density are accurate and identical on all copies coming off
the press. A final check for acceptability usually occurs, then the press run begins.
Although an essential step, everything generated in makeready is waste. Finding ways to
reduce makeready yields multiple benefits by saving waste paper, chemicals and time which
in turn results in less waste disposal costs and money saved.
A strict quality control program will help eliminate waste by correcting problems as
they arise. It is helpful to include in this program a process where periodic "press
checks" are performed by an unbiased party to verify the quality of the product
during a press run. The majority of the techniques available to printers to reduce waste
at the press can be classified as good housekeeping and material substitution. Figure 6
shows a typical lithographic press roller arrangement.
The printing process itself produces scrap paper, waste ink, cleaning solvents which
result in VOC emissions as does the ink drying process. According to one study on VOC
emissions, the average VOC emission at three offset printing shops was 2 tons per year. In
lithography, a majority of the VOCs from the ink stays with the product. With non-heat set
inks, approximately 95 percent of the VOCs from the ink stays with the product, while in
heat set inks approximately 60 percent remains.
Inks
Ink substitutions for the standard petroleum-based inks are now available in the form
of ultraviolet-curable or electron beam inks, and vegetable-based inks, including soy
oil-based inks. Customer requirements can dictate the type of ink used.
Fountain Solution
Isopropyl alcohol (IPA), added to the fountain solution at a rate of 2 to 15 percent,
has been the most common additive used in fountain solutions and holds the distinction of
being one of the main contributors to VOC emissions from lithographic printing facilities.
Refrigeration of the fountain solution is usually used to reduce the evaporation of the
IPA. Switching to an alternative fountain solution with lower or no VOCs is a good
pollution prevention option. Typically low or no VOC fountain solutions cost more based on
volume because the cost to produce these products is significantly greater compared to
IPA. Due to stringent federal air quality standards the use of these alternative products
is beginning to increase. Additionally, due to permitting and recordkeeping requirements,
no VOC fountains solution may prove to be more cost effective in the long-term.
In lithographic printing, alcohol substitutes, such as glycol ethers, can be used in
some dampening systems. These substitutes reduce the surface tension of the fountain
solution but have a more complex chemical structure and higher boiling point than the
alcohol dampeners. To determine if a substitute is applicable it is important to consider
the ink, press type, paper, type of dampening system, and printing constraints. This is
one of the easiest ways to minimize emissions.
Of concern with determining the substitutes compatibility and performance with the
fountain solutions are the temperature, pH, and conductivity. The conductivity of the
incoming water affects the performance of the alcohol substitute. An automatic mixing
system will accurately mix fountain solution to the proper concentration and can somewhat
reduce risks of problems from varying conductivity. Hard water causes calcium deposits and
requires an additional water softening system. This problem was formerly masked when using
an alcohol fountain solution. Some large operations have chosen deionizing units or
reverse osmosis to remove salts, minerals and organic matter which would affect the
performance of the alcohol substitute. Water temperature will now affect the viscosity of
the substitute and therefore the ink transferability.
Alcohol substitutes also have a foaming problem. This problem can be eliminated by use
of a foam free recirculating system which mechanically eliminates foam rather than
chemical anti-foaming agents. Adding filters to the recirculating units will remove
contamination and ink residue, effectively extending the life of the solution. Evaporation
of the mixture can be reduced by the installation of a refrigeration unit. However, ink
viscosity could be increased with a cooled sump, which may effect the printing
performance. Any changes implemented will have to go through a "shake-down"
period of trial and error until the best working conditions are determined. The roller
condition and durometer (hard/soft) will become much more important.
Cleaning Solutions
Cleaning of the press occurs most often during make-ready as adjustments are made to
the press and plates, during the actual press run, between press runs, and at the end of
the day (shut down). The frequency of press washes depends on many factors including paper
dust and dried ink accumulation, the quality of the paper, and the habits of the
particular press operator. Ink rollers and plates are typically cleaned in place with a
solvent. Residual ink is dissolved in the solvent and scraped from the roller with a
blade. The resulting solvent/ink waste is collected in a tray. Blankets are cleaned during
and following a run or after a color change. Most blanket cleaning is done with solvent
wetted rags. Common cleaning solvents include methanol, toluene, and trichloroethane,
while naptha, methylene chloride, and a variety of specially formulated solvent blends may
be used (Jendrucko, 1995).
For larger presses, installing automatic blanket washers can increase press efficiency
and safety. The blankets can be cleaned during a press run rather than stopping the press
and using manual cleaning methods. Due to speed of cleaning there are fewer wasted
impressions (paper) and less cleaning solution used. Worker safety is improved through
less exposure to moving equipment, air emissions, and harsh cleaning compounds.
Parts Washing
Any parts washer at the printing facility may have the ability to be retrofitted or
replaced with units containing filters to extend the life of the solvent. One type of
parts washer now on the market utilizes a cyclone type filter that removes the solids and
then recirculates the solvent. Alternative cleaning solvents are available as well. Many
products such as d-limonine based compounds will work just as well as petroleum-based
solvents. They are less harmful to workers, emit less VOCs into the air and can be
disposed of as non-hazardous waste. However, they emit a citrus smell to which workers
will need to become accustomed. When leasing parts washing units ask the supplier about
how the solvent is treated/recovered and what options are available.
Wastes generated from the finishing process include waste paper and VOC emissions,
contaminated or spilled materials such as glue and laminates. Waste paper is created from
trimming, off spec product and printing overruns.
"Waste Minimization for the Commercial Printing Industry," Factsheet, State
of California Department ofToxic Substances Control, 6 p., 1992.
"Hazardous Waste Minimization Checklist & Assessment Manual for the Printing
Industry," California Environmental Protection Agency Department of Toxic Substances
Control Office of Pollution Prevention and Technology Development, Sacramento, CA, 1994.
Barwick, Kathryn. "Pollution Prevention Assessment of the Office of State
Printing," California Department of Toxic Substances Control, Sacramento, CA, 1991.
"Printing and Publishing Industry, Pollution Prevention and Recycling: Student
Manual," Illinois Environmental Protection Agency, Office of Pollution Prevention,
Springfield, IL and Center for Hazardous Materials Research, Pittsburgh, PA, 1994.
"A Guide for Lithographic Printers," Washington State Department of Ecology,
Environmental Management and Pollution Prevention, 1994.
"Prevention Factsheet: Offset Printing Businesses," Stimular, Netherlands,
June 1994.
"Printing and Publishing Industry Workshop Manual," Illinois Environmental
Protection Agency, Office of Pollution Prevention, Center for Hazardous Materials
Research, Springfield, IL.
"Guides to Pollution Prevention: The Commercial Printing Industry,"
EPA/625/7-90/008, U.S. EPA Office of Research and Development, Washington, DC, August
1990.
"Multimedia Compliance/Pollution Prevention Assessment Guidance for Lithographic
Printing Facilities," DCN: RZ3-SAI-R11012-WA-00393, U.S. EPA Office of Enforcement
and Compliance Assurance, Washington, DC, August 1995.
"Environmental Management Program," Printing Industries of America, Inc. and
"Compliance Plus Guide—Environmental Compliance and Pollution Prevention for
Illinois Lithographic Printers," 1996, Printing Industry Publishing Corporation.
A good general reference for all lithographic printers, even thought the document
targets Illinois-specific regulations. Has worksheets to follow for determing compliance
status.
"Pollution Prevention Assessment of the Office of State Printing," California
Environmental Protection Agency, Department of Toxic Substances Control, Doc. No. 519,
44p.
A good report of an assessment on California lithographic operation and the pollution
prevention suggestions to be examined for further consideration and implementation.
"Waste Audit Study-Commericial Printing Industry" by Jacobs Engineering Group
Inc., Hazardous and Toxic Materials Division for California Pollution Prevention and
Technology Development, Department of Toxic Substances Control. Doc. No. 303.
A good overall report with descriptions of various waste minimization techniques; also
presents a number of case studies of California printers.
"Guide to Pollution Prevention in the Commercial Printing Industry," U.S. EPA
Risk Reduction Engineering Laboratory and Center for Environmental Research Information,
1990, 45 p.
This report covers basics of all printing wastes and pollution prevention efforts;
includes worksheets for conducting an assessment of a printing facility.
"Control of Volatile Organic Compound Emissions from Offset Lithographic
Printing" Guideline Series Draft. US EPA Office of Air Quality Planning and
Standards, September 1993.
Lengthy report on methods and techniques used to control VOC emissions at lithographic
printing facilities; includes a variety of control strategies, costs associated with these
techniques, impact analysis and selection of reasonably available control technologies,
and factors to consider in implementing a control technology.
"A Guide for Lithographic Printers" Washington State Department of Ecology,
Environmental Management and Pollution Prevention, Report No. 94-139, September 1994.
A good primary resource for the lithographic printer. Has good checklists of Do's and
Dont's for each major wastestream.
"Pollution Prevention Manual for Lithographic Printers," Iowa State Waste
Reduction Center, 1995.
An excellent resource with current information. Geared toward printing plant personnel,
rather that technical assistance providers. Covers every step in the lithographic printing
process and provides alternatives to current waste-generating practices, provides real
life examples with case studies.
"Pollution Prevention: Strategies for the Printing Industry," Center for
Hazardous Materials Research Factsheet, n.d.
Has very general information on pollution prevention and list options for paper, waste
lubricating fluids for machinery, waste chemicals, equipment cleaning wastes, and process
wastewaters.
"Water, Water Everywhere...But Not a Drop in the Ink," Graphic Arts Monthly,
November 1991.
The article details the conversion of a company to waterless offset lithography.
"The Seminal Soybean," Graphic Arts Monthly, November 1991.
Article contains information on soy-based inks, examples from companies who have
switched from petroleum based inks, procedures needed to get soy oil seal.
Chuang, J.C., D.A. Burgoon, B.E. Buxton, S.C. Liao, and G.M. Sverdrup. "Ink Oil
Loss is Sheet-Fed Lithographic Printing" Battelle, March 1993.
In-depth scientfic report determining fraction of ink oils lost from ink during
printing process and ink loss from sheetfed lithographic prints during storage.
Cross, Lisa "Ink Waste Disposal," Graphic Arts Monthly, vol. 61, May 1989.
Lists current options for ink waste disposal and alternatives to disposal through waste
minimization techniques.
Cross, Lisa "Litho Plates Get Eco Friendly," Graphic Arts Monthly, May 1993.
Discusses new governmental regulations due to Clean Air Act Amendments of 1990 and how
some printers have switched from solvent-based plates to aqueous-based plate systems.
Provides good overview on wastewater treatment plant operations with respect to printers.
Erhan, Sevim Z. and M.O. Bagby "Vegetable Oil-Based Vehicles, News Ink Formulation
and Their Properties," 1992 Proceedings of the Technical Association of the Graphic
Arts, pgs. 409-425.
Technical article on vegetable oil-based printing ink vehicles. In-depth information on
the chemical and physical properties of inks produced in this study.
Gavaskar, A.R., R.F. Olfenbuttel, and J.A. Jones. "On-site Waste Ink
Recycling," US EPA RREL, EPA/600/SR-92/251, February 1993.
Good example of process modification to recycle waste ink, specific to newspaper
presses.
Gilbertson, T.J. "Mixing Water with Electrical Energy: Successful Printing with
Water-based inks," 1991 Polymers, Laminations & Coatings Conference.
Technical paper on developing successful water-based printing operations.
Hultquist, S.R. "Overall Waste Disposal Management," 1993 Proceedings of the
Technical Association of the Graphic Arts, pgs. 511-525.
This article is a regulatory overview that lists current techniques available for
disposal of common waste streams. Contains lots of information on federal regulation and
compliance issues.
Johns, David R. "Environmentally Safe Fountain Solutions for the Printing
Industries" in Innovative Clean Technologies Case Studies Secondy Year Project
Report. US EPA, Office of Research and Development. EPA/600/R-94/169, p. 202-214.
Report details methodology behind the development of a fountain solution for offset web
presses with high speed printing and other sheet-fed presses that eliminates isopropyl
alcohol and mineral acids; includes demostration procedure, evaluation parameters,
performance results, and incentives and barriers to using this solution.
Telschow, Roger. "Reducing Heavy Metal Content in Offset Printing Inks" in Innovative
Clean Technologies Case Studies Second Year Project Report. US EPA, Office of
Research and Development. EPA/600/R-94/169, p. 117-125.
This report details the methodology behind development of a printing ink with reduced
heavy metal content for sheet-fed lithography; includes performance results from test
press runs, cost/benefit analysis, and incentives and barriers to using this ink.
Toth, Deborah. "Waterless Web: Steady, Not Spectacular" Graphics Art Monthly,
May 1996, pp. 61-62.
A review article about the current state of waterless web, with information on the
plate producer, Toray. Also opinions from printers using waterless web are presented.
Wadden, R.A., P.A. Scheff, J.E. Franke, L.M. Conroy, and C.B. Kell "Determination
of VOC Emission Rates and Compositions for Offset Printing," July 1995. J. Air and
Waste Manage. Assoc. 45:547-555.
Technical paper on methods used to test the concentration of VOCs in indoor air of 3
different size printing facilities.
Watkins, L.A. "A Multi-Disciplinary Approach to Ink Recycling," 1992
Proceedings of the Technical Association of the Graphic Arts, pgs. 604-615.
Easy to read and understand article on ink recycling. Provides examples of processes
and equipment used to reclaim ink, and case studies with numerical data.
Case Study 1
Aetna's In-house Printing Plant Leads the Way Pollution Prevention:
Environmental Management's Next Goal
Michael Feldman
GAFTWORLD Vol. 5, Issue 6, 1993
Aetna's printing plant employs 130 people and does approximately $15 million worth of
commercial offset printing, primarily sheetfed, yearly. They run a six color, 2 two-color,
and a four color press. The pollution prevention program undertaken at Aetna consists of a
number of different projects.
They eliminated alcohol from the dampening solution which caused some problems with the
ink and water balance. The problems were solved by: 1) changing the electronics of the
press to cut off the dampening system sooner to eliminate water in the ink; 2)
reformulating inks with vendor assistance; 3) switching to a different chemistry in the
dampening solutions; 4) reconfiguring all the rollers and switching from crown to parallel
rollers and experimenting to find the optimum settings; and, 5) switching to lesser
grained plates. The results from this changeover included a decrease in liquid hazardous
waste from 11,000 gal./year to 5,000 gal./year with a savings of $42,000 annually in
disposal costs.
Dampening solution disposal was another project undertaken by the facility. The used
solvent was dumped at a designated sink location, pumped through two activated charcoal
canisters, and then discharged directly into the municipal sewer system. Contamination
problems from other materials dumped into the sink led the company to develop a "pump
mobile." This is a cart with a 55 gal. drum and pumps that moves from press to press.
The used dampening solution is pumped into the drum, then the cart is moved to the
cleaning station where drum contents are pumped into the activated charcoal system. This
project costs $2,000 annually to recharge the activated carbon and saves $48,000 in
disposal costs.
Ink reclamation saves the company $200,000 in ink disposal costs alone and $90,000 on
reduced new ink purchases each year. Previously, premixed inks were ordered on a job by
job basis resulting in 7,500 lbs. of ink in inventory. Much of this ink was special
ordered and if the print job changed or was cancelled, the ink was unusable. Computer
software was ordered to allow better planning and estimates as well as to provide the
ability to mix new Pantone colors from existing mixed Pantone colors. This helped to
eliminate the unused ink in inventory. Also, waste and excess ink returned from the
presses has been used to make black ink. The company is also starting to use vegetable-oil
based inks with lower VOC content.
Other efforts undertaken in Aetna's pollution prevention program include: switching
from a chlorinated to nonchlorinated wash-up solution; instituting a parts washing system
that allows reuse of parts cleaning solvents; recycling all wastepaper; trying to reduce
the number and variety of chemicals used in the printing operation; and, making sure
vendor facilities comply with environmental regulations. |
Case Study 2
Pollution Prevention Works for Iowa: Case Summaries
Moore Business Forms & Systems Division
May 1994
Moore prints custom business forms for a wide range of customers. The company wanted to
find ways to use the paper waste not amenable to recycling such as carbon-backed, coated,
mixed and "dirty papers". In partnership with a number of different groups,
Moore developed a refuse-derived fuel cubing program in 1992. The process shreds waste
materials, adds moisture for proper mixing and compaction, removes tramp ferrous metals
with magnets and extrudes material into fuel pellets. The product is sold to coal fired
power plants that mix the cubes with coal at approximately a 10 percent ratio of total
fuel. The company in now able to divert essentially all unrecyclable paper waste to fuel.
Through diverting 912 tons/year from the landfill, Moore saved $10,032/year in landfill
fees. When transportation savings are included the savings total $11,832/year. |
Case Study 3
Toxics Use Reduction Case Study
Alcohol Free Fountain Solution at Americraft Carton, Inc.
Office of Technical Assistance, Massachusetts
September 1993
Americraft Carton, Inc. is a $30 million a year folding carton manufacturer and
printer. Until August 1991, Americraft mixed fountain solution for its presses in the
traditional manner. A solution of 15-25 percent isopropyl alcohol (IPA), tap water, and
etch material was measured by hand into a drum and stirred with a wooden paddle.
Americraft received bulk deliveries of IPA every two to three weeks. Up to six 55 gallon
drums of waste solution were generated monthly by the company's four sheetfed offset
presses.
There are significant economic, health and safety, and environmental drawbacks to this
method of producing and using fountain solution. Inconsistency in the solution can cause
press downtime. It also involves increased labor and material costs, and it can require
disposal of inadequate, unused, or waste solution at a cost of more than $2 per gallon.
Inhalation of alcohol-laden vapors present health and safety concerns for employees. IPA
is an ozone producing volatile organic compound (VOC), thereby increasing the cost and
complexity of air emission permitting and reporting.
The company purchased and installed the new no-IPA system at a cost of $108,000. The
system is a closed loop recycling system connected to all the presses, which can release
solution at up to 15 gallons per minute. Recharging of the solution (made up of water
obtained by reverse osmosis, IPA substitute (Prisco Q-11), and used fountain solution) is
computer-controlled to ensure that pH, temperature, and conductivity are all precisely
maintained. From the press, the solution goes to a return tank where it is chilled and
filtered to 25 microns (contaminants are ink, paper, dust, and paperboard stock). The
solution is then returned to the main system for filtering to 10 microns and for further
chilling as well as solution recharging. The chiller is a holding tank with a 250 gallon
capacity to ensure adequate quantities at all times.
The new system has resulted in: the end of losses and costs associated with hand mixed
solution; the cost and disposal cost of unacceptable solution that also sometimes caused
press downtime; reduced costs for waste removal by internal recycling of the solution and
from converting from weekly solution disposal and pan maintenance to an annual schedule;
and, significantly reduced use of VOCs and VOC emissions through the replacement of IPA.
The $108,000 equipment investment had an expected payback resulting solely from the
reduced cost for materials of about 30 months after introduction of the new system. There
are substantial additional savings from increased press efficiency, reduced wastes, and
reduced and eliminated permit costs. Americraft has also found that alcohol substitutes
increase the rate of roller replacement and maintenance, but also require lower durometer
settings meaning they may last longer. |
Case Study 4
Case Histories of Cost Saving Through Waste Reduction by Small Industries in
Tennessee
TVA 8: Magazine Printing
Tennessee Valley Authority
A magazine printer substituted well water for all process cooling water and lawn
sprinkling to reduce potable water use and associated sewer charges. The change resulted
in a $10,000 savings in sewer charges annually. The company also used water-based
detergent for cleaning most surfaces and used a petroleum naptha cleaner for washing metal
press parts. A parts-cleaning station containing 25 gallons of the cleaner was rented for
each printing press. During each change-out, approximately 15 gallons of cleaner vaporized
into the work areas. The company reduced the number of stations from 43 to 4 and cleanout
frequency went from every two weeks to three weeks, saving $5,000 annually. An ink mill
was installed to salvage waste ink and formulate an acceptable blend of recycled and new
ink to reduce costs of purchasing new ink and disposing of waste ink. The mill salvaged 90
percent of waste ink, saving an estimated $200,000 to $250,000 annually. |
Case Study 5
Managing Solvents and Wipes
Design for the Environment Printing Project Case Study
US EPA, 1994
The John Roberts Company in Minneapolis employs 240 people and prints annual reports,
brochures, catalogs, forms, limited edition fine art prints, and direct mail pieces using
sheet-fed and web offset processes. The company studied their solvent use practices
because the industrial laundry that cleaned their leased towels was having problems
meeting the regulations for discharging to the sanitary sewer.
The company thoroughly investigated the reasons they were using the solvents, the
properties that the solvent required for their needs, and how the solvents were applied by
the press personnel. The goal was to find a substitute solvent that was better matched to
the task that did not substantially affect work procedure or productivity.
The raising of awareness in the effort to find a substitute resulted in a reduction in
the misuse of the all-purpose cleaning solvent. Usage of the solvent, which was a mixture
of acetone, toluene, MEK, and isopropyl alcohol, was reduced from 152 fifty-five gallon
drums to 5 in the first year. A new replacement solvent, an ultra-fast blanket wash, was
blended especially for the company and performed well with respect to speed and lack of an
oily film.
Only 38 fifty-five gallon drums of this new blanket wash were purchased in the first
year. Even after including the purchase of the replacement solvents, the company saved
more than $18,000 in the first year by changing solvents and using them more prudently. In
addition, the contribution of the company to the laundry's effluent no longer exceeded
limits.
An additional effort undertaken was the purchase of a centrifuge to remove solvent from
the wipers prior to sending them to the laundry. This technique saved the company $34,000
in the first year alone, resulting in a quick payback of less than one year on the $15,000
centrifuge price.
The company continued making improvements on the solvent alternative, and replaced it
with a reformulated and less volatile press wash that eliminated the 1,1,1 trichloroethane
present in the former solvent. With less volatilizing to the air, the company has found
that it purchases 4 fewer drums of solvent each month. |
Case Study 6
Pollution Prevention Efforts at the Journal Press, Inc.
Vermont Agency of Natural Resources, Pollution Prevention Divisionin Pollution
Prevention Successes: A Compendium of Case Studies From the Northeast States, NEWMOA
December 1993
The Journal Press, Inc., is a small commercial offset lithographic printing business.
Production activities at the company include photo processing, plate making, printing and
book binding.
The fixer from photo processing operations is run through an ion exchange unit to
recover the silver. The Journal Press receives payment for the silver recovered from this
process. The company sells the used plates and film to a scrap metal dealer for resale.
The Journal Press has located low toxicity substitutes for a majority of the hazardous
chemicals used in the printing process. Isopropyl alcohol has been eliminated in 99.9
percent of printing jobs through chemical substitution with a mixture of butyl cellosolve
and glycol ether. The new fountain solution requires press operators to take more time
during the make ready process to ensure that all press adjustments are exact. Once the
press is adjusted, the new solution does not have an adverse effect on the speed of the
printing operation. However, it has been observed that after operating a press
continuously for three to four months with the new fountain solution some printing
problems may occur. These problems may be corrected by adding a very small amount of IPA
to the system.
Waste ink is the only waste stream shipped off-site for disposal. Good housekeeping,
such as using just enough ink to do the job, keeping all ink containers closed except when
ink is being removed from or added to the containers, and keeping ink used during
production in small containers, reduces the amount of waste ink generated. The company is
also actively seeking a recycling outlet for its waste ink. |
Case Study 7
Waste Water Reduction at the Stinehour Press, Inc.
Vermont Agency of Natural Resources, Pollution Prevention Division in Pollution
Prevention Successes: A Compendium of Case Studies From the Northeast States, NEWMOA
December 1993
The Stinehour Press has had significant success in reducing the volume of waste water
generated from their printing and photo processing activities. Many printing companies
discharge waste waters from these processes to POTWs or discharge the waste to surface
waters under the auspices of a NPDES permit. No POTW was available to the Stinehour Press
and discharge to the Connecticut River was considered to be technically difficult and
economically infeasible. In the late 1980's the company began collecting its waste waters
and managing them as hazardous waste. Costs related to management and disposal of the
waste mounted and concerns related to potential long-term liability heightened. These two
issues, cost and liability, became the driving forces behind waste water and toxic use
reduction at the facility.
The volume of waste water managed by Stinehour Press has been reduced through a
combination of closed-loop recycling and evaporation. Prior to implementing these methods,
up to 10,000 gallons of water were used daily to operate the film processors and up to
5456 gallons of waste water from other sources, some of which were deemed hazardous, were
generated annually. Presently, the company has reduced film processor waste waters to 100
gallons per week through recycling and has reduced hazardous waste water streams to 77
gallons per month.
Film Processor Wastes
The film processors at the facility use 12 gallons of rinse water for each sheet of
film processed. During peak operation, this could be as much as 10,000 gallons per day.
These rinse waters contain low concentrations of silver (.02-.05 ppm). Although these
waste waters were not considered to be hazardous waste, concerns were raised as to whether
the material would continue to meet strict groundwater discharge requirements.
Additionally, concerns were raised regarding the stress to the environment related to
continued removal of such large quantities of water from the company's well system.
On-site discharge of film processor waste water has been eliminated and water
consumption has been drastically reduced. This has been achieved in part through the
installation of four small ion exchange units. These units are hard-piped to individual
film processors. Rinse water from the film processors flows into a reservoir on the
recycling unit. A small pump then forces the rinse water through the ion exchange column.
Silver ions within the rinse water are exchanged with ions from the resin column.
De-silvered water leaving the resin column is further filtered to remove any resin
particles which may have been dislodged during the recycling process. The recycled water
is then pumped back into film processors.
The plumbing within the ion exchange systems is equipped with valves which allow the
operator to back flush the system. This is considered to be an important feature because
it allows the operator to "fluff" the resin within the non-exchange column.
"Fluffing the resin" reduces the effect of channeling within the ion exchange
column and helps to maintain the efficiency of the system.
Company personnel collect 25 gallons ofspent rinse water from the ion exchange units on
a weekly basis. The water is evaporated on site under the terms of a state permit. The ion
exchange columns within the recycling systems are removed every three months. The spent
ion exchange columns are returned to the manufacturer for silver recovery and
regeneration. After regeneration the ion exchange columns are returned to the Stinehour
Press for reuse.
Spent Fixer
The company uses a batch type electrolytic silver recovery unit equipped with a tailing
system to remove silver from spent fixer. During the electrolytic process an electrical
current is applied to two electrodes which are immersed in the fixer. Silver from the
solution collects on the cathode. Silver flake is removed from the silver recovery unit
periodically and sold.
An ion exchange tailing system is used to further remove silver from the spent fixer.
This second silver recovery step ensures that spent fixer is not a hazardous waste based
on its silver content. The tailing cartridge is also sent off-site for silver recovery and
regeneration. The de-silvered fixer is stored on-site until it can be evaporated.
Evaporation
Film processor water, spent developer, de-silvered fixer, fountain solution, and press
bucket water are collected on-site and evaporated to reduce the volume of water in these
waste streams. None of these waste streams are considered to be hazardous waste under the
provisions of the Vermont Hazardous Waste Management Regulations. However, the waste
streams do contain low concentrations of solvent and silver and are not considered
suitable for on-site discharge.
Initially silver, chrome, and formaldehyde levels were of concern to the Vermont Agency
of Natural Resources. The concerns about the silver levels were addressed by adding the
tailing system to the electrolytic silver recovery unit. The presence of chrome was due to
the use of a film processor cleaning solution which contained sodium dichromate. A
non-chrome containing replacement for this solution was found.
A cost analysis outlining the expenses and savings associated with the project appear
below:
Gross Annual Savings $45,042
Operating & Disposal Costs $18,105
Net Annual Savings $26,937
Gross Equipment Costs $38,247
Amount of State Grant $15,020
Stinehour Investment $23,227
Payback period on Gross Cost 1.6 years
Payback period on Stinehour Investment 0.9 years
Percentage of Waste Reduced 92.5 percent
This analysis does not include figures relating to the reduction in the volume of film
processor rinse water used prior to recycling. The amount of rinse water required by this
process has been reduced by more than 99 percent. |
Case Study 8
Case Study: McNaughton & Gunn, Inc., Saline, MI
Michigan Department of Environmental Quality, Environmental Assistance Division
November 1995, #9509
McNaughton & Gunn prints books and as a company strives to prevent or minimize the
waste they generate. Source reduction strategies such as substituting raw materials,
working with suppliers to reduce input packaging, and office management changes have
become key components of the company's approach to eliminating hazardous and solid waste.
Through the efforts of a volunteer employee committee, dubbed the "Recycling
Fanatics," the company has achieved source reduction in the following ways:
- Purchased two new ink pumping systems
The first system pumps vegetable based black ink from 55 gallon refillable drums
through pipes in the ceiling to four sheet fed presses. The second system pumps black ink
from 3,000 pound totes to two web presses. The totes are returned to the ink manufacturer
for refilling. The 55 gallon drums and the 3,000 pound totes replaced five and ten pound
cans that came in boxes with cardboard separators
- Modified beverage vending machine to eliminate disposable cups
The company provides each of it's 250 employees with a ceramic mug to use in place of
polystyrene cups.
- Modified purchasing policies
Janitorial supplies are now purchased in bulk and aerosol cans have been eliminated.
- Modified all three film processors so they are on a complete chemistry recycling system
The developer has a rejuvenator added to it to prolong its life. The fixer goes through
a silver recovery unit and is then returned to the processor. This is a closed loop system
and the only replenishment needed is to compensate for oxidation.
- Purchased an office copier capable of two-sided copying
This resulted in a major reduction in paper use and a savings in paper purchase costs.
- Purchased a new projection system that requires less film and fewer chemicals for
developing
- Implemented an electronic communications system that eliminated the need for most memos
All Requests for Quotes and purchase orders are also done electronically, thereby
reducing paper use.
In 1995 McNaughton & Gunn generated an income of $280,000 from recycling film plate
and paper. New recycling programs, along with source reduction strategies, allowed the
company to reduce solid wastes by half. The company is recycling in the following ways:
- Vegetable based colored ink is still received in five pound cans due to the small
quantities ordered. The cans and lids are all recycled and the cardboard boxes and
separators are picked up by the ink manufacturer for reuse.
- A large Cyclone Scrap Removal System was installed on the roof of the facility. The
system creates vacuum points and picks up paper waste and trimmings that are generated by
machines in the plant. The waste is transported through ceiling pipes to a paper baler
where it is compacted and tied with wire into 1,500 pound bales. The bales are then loaded
on semi-trailers and transported to a paper mill for recycling.
- Film scraps are sent off-site and processed to reclaim their silver content.
- Over 125,000 pounds of aluminum printing plates are recycled each year.
- Each workstation has a recycling basket to collect office paper for recycling.
- Batteries used in the plant and in the employees' homes are recycled.
- Wood waste from broken pallets is shredded (by an outside vendor) into wood chips.
Other steps the company has taken to contribute to preserving the environment include:
Changed to an environmentally friendly chemistry system for plate developing.
- Now use vegetable based ink on all sheetfed presses.
- Totally eliminated isopropyl alcohol form the dampening systems of all presses.
- Now use low VOC solvents for blanket and roller washes.
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Case Study 9
Technology Creates Really "Green" Ink, New Process Enables 100
Percent Recovery from Hazardous Sludge
The P2 Alert, Tennessee Div. of Pollution Prevention & Environmental Awareness
Autumn 1995
Thanks to the ingenuity of Knoxville inventor Frank Prasil, printing ink residue at
lithographic print shops can be completely eliminated from the waste stream and used to
formulate quality ink.
Prasil has discovered how to change ink sludge from lithographic printers, a gooey
hazardous waste, into high grade ink. In addition to being economical and environmentally
positive, the ink is rich in pigment. Even compared to ink manufactured from virgin raw
materials, recycled ink generated by this process has superior printing qualities,
generates less process waste, and prints better on recycled paper.
The process, known as Lithographic Ink-Waste Recovery Technology (LIRT), recovers 100
percent of the waste sludge, composed of oil, oxide pigments, solvents and acid wash
waters. Lithographic printers currently incinerate more than 60 million pounds of this ink
sludge.
Recovery of usable components occurs with no solid, liquid or gaseous emissions to the
environment.
The waste ink which once represented a disposal and reporting liability for printers is
now a $2000 per barrel asset. In addition to the money savings this process represents, it
also conserves natural resources. Prasil estimates that his ink recovery system can save
an equivalent of 560 million cubic feet of natural gas and 660,000 barrels of crude oil,
and can reduce air pollution by 3,780,000 tons. The ink recovery also uses 98.5 percent
less energy than manufacturing ink from virgin raw materials. European countries, which
lack the richness of raw material resources of the United States, could prove an eager
market for LIRT ink.
The inventor is currently working to secure patent rights and submitted a National
Industrial Competitiveness through Energy, Environment, and Economics grant proposal to
the Department of Energy, in cooperation with the University of Tennessee Center for
Industrial Services (UT-CIS) and the Tennessee Department of Environment and Conservation.
This grant was awarded and the project in underway.
If you have an interest in trying the LIRT ink or learning more about the ink recycling
process, contact the UT Center for Industrial Services in Nashville, 615/847-8007.
Update From: Tennessee Materials Exchange Bulletin, Summer 1996, Bulletin No. 3
The black ink is produced from ink wastes that would normally be disposed of, e.g.
wash-up solutions from cleaning lithographic presses and residues from air-exposed ink
fountains that feed presses. Let's be clear--this is not "reused" ink from
half-filled containers. This is "recycled" ink and the Department of Energy has
awarded Prasil a grant for commercial product development. While commercial quantities of
inks should be available by the end of the year, small quantities of "recycled
black" are available now, and various earth tones will be developed in the near
future. |
Case Study 10
Running "Green," An Environmental Case Study
Stu McMichael
Business Management, Printing Industries of America, Inc.
1993
Custom Print runs a full service printing company in Virginia. The company began their
own environmental consciousness raising by experimenting with various alternative
chemicals to isopropyl anhydrous alcohol. During a five year period, the company went
through seven different products, each better than the last. As they worked on improving
their pressroom environment, they realized that they needed to do a full-scale
environmental review of every department, from camera and stripping to
platemaking to bindery to shipping to front office. Each department head reviewed all the
chemicals used and was asked to come up with better alternatives whenever possible.
Using OSHA and EPA standards as benchmarks, the company took steps to go beyond
existing requirements. Some examples:
- Completely changed the way they made plates, switching to an aqueous plate processing
system, drastically cutting polymer waste.
- Converted to soy inks, now using them exclusively with excellent results.
- Use water from four dehumidifiers controling moisture buildup in their paper in press
water fountains.
- Recycle all paper, including office paper waste.
- Print the great majority of their jobs on recycled paper and educate customers on what's
available.
- Retrieve film from camera and stripping departments and recycle it. Silver from the film
and developing fluid is extracted, collected, then sent to a mint and pressed into
one-troy-ounce coins of pure silver. These coins are given to the people working at the
press for Christmas presents.
The transition to environmentally friendly materials has been expensive due to the need
to experiment with different chemicals, plates and papers. On the bottom line, for this
press it does cost more to produce their products. But the marketing edge in their
environmentally conscious community is a benefit that far outweighs the downside. |
Case Study 11
Cleaner Technologies Substitutes Assessment for Lithographic Blanket Washes
Design for the Environment, US EPA
EPA-744-R-95-008
August 1996
The first major publication of the DfE Lithograpy Project, the draft Cleaner
Technologies Substitutes Assessment for Lithographic Blanket Washes (CTSA), is now
available. The DfE Lithography project partners have evaluated the trade-offs associated
with using 37 different lithographic blanket washes. They examined costs, performance,
environmental hazards, and human health risks of each blanket wash. The Lithographic CTSA
presents the results of these extensive studies. It contains detailed technical
information, including:
- Results of the blanket wash performance demonstrations and a cost analysis for each
product;
- Descriptions of the individual chemicals used in the 37 blanket washes and of the human
health and environmental hazards associated with these chemicals;
- Discussions of the environmental and occupational risks inherent to each blanket wash
solution as a whole, including VOC content and flammability;
- Discussions of relevant international trade issues, energy and natural resource issues,
and Federal regulations; and,
- Descriptions of pollution prevention opportunities, emphasizing simple changes that can
be made to everyday work practices.
The CTSA is valuable resource for anyone intersted in the lithographic printing
industry. For example:
Suppliers can use the CTSA for a variety of purposes. They may use the comparative
risk, performance, and cost analyses to identify which blanket wash chemicals and
formulations are best suited for the current market. Suppliers interested in manufacturing
new blanket washes can use the environmental and human health data presented for
individual chemical components as a building block for designing more environmentally
friendly formulations.
Technical assistance programs can use the CTSA as a source of background information on
lithography, blanket washes, and the DfE Lithography Project. They will find the
comparative risk, performance, and cost analysis useful when working with printers to
reduce VOC emissions and hazardous wastes.
Printers will be interested in the in-depth information on blanket washes and their
chemical components. The performance methodology used to evaluate blanket washed may also
be helpful. Printers can use this methodology to conduct their own performance evaluations
of blanket washes or of other alternative products or processes.
A free copy of the Draft CTSA may be obtained by contacting EPA's Pollution Prevention
Information Clearinghouse (PPIC) at: US EPA, 401 M St. SW (3404), Washington, DC 20460. It
can also be downloaded from the DfE Web page at http://es.inel.gov/dfe (was not yet up
on the Web as of Aug. 23, 1996). |
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