PRINTED WIRING BOARD CASE STUDY 6
A Cooperative Project
between the
U.S. Environmental
Protection Agency
and PWB
Manufacturers
Nationwide
                                        PRINTED WIRING
                                        BOARD PROJECT
                                  Pollution Prevention
                                    Beyond  Regulated
                                             Materials
                                       The most successful pollution prevention
                                       programs involve looking for
                                       opportunities "beyond the barrels."
                                 Whereas pollution prevention most commonly
                                 takes the form of chemical use and waste
                                 reduction, by maintaining a chemical-specific
                                 focus you may overlook less obvious
                                 opportunities, such as in energy and water
                                 conservation. For one facility, Tri-Star
                                 Technologies, Inc., in Methuen, Massachusetts,
                                 broadening its view of pollution prevention led
                                 to energy and water use reductions that have
                                 resulted in significant cost savings. These
                                 energy and water reduction projects are the
                                 focus of this case study.

                                 Getting Started

                                 Tri-Star Technologies, Inc., is a manufacturer of
                                 double-sided and multilayer printed wiring
boards, specializing in products for the elec-
tronics industry. With 220 employees at its
120,000 ft2 facility, Tri-Star produces 1,000,000
surface square feet annually.

As Tri-Star implemented its pollution prevention
program, this company discovered that
demonstrating cost savings is the key to a
successful program, especially when first getting
started or when jump-starting a slow-moving
program. Initially, Tri-Star implemented a few
projects that required little capital investment.
When it was able to show the cost savings
achieved from these projects, the credibility of
pollution prevention as a good business practice
grew.

Today, with several successes to its credit, Tri-
Star's pollution prevention team now is able to
obtain funding for projects that do require larger
capital investments. These projects also offer
increased cost savings over the long term.  For
example, the facility is currently installing a
cupric chloride regeneration system to recycle
inner-layer etchant (see Printed Wiring Board
Case Study 2 for more information on etchant
regeneration).  Such a system might require a
capital investment of $150,000 or more, but the
payback is expected to be less than 18 months by
achieving dramatic reductions in spent etchant
and virgin chemical purchases, and by selling the
recovered copper by-product. Requiring a
significant investment, this project has come
about only after the pollution prevention concept
gained credibility through the success of "low
tech/no tech" projects.

By looking beyond regulated materials, Tri-Star
found cost-saving opportunities in energy and
water conservation. Such opportunities are a
"cheap, easy, and often overlooked way to reduce

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your facility's environmental impact while saving money," says
Ed Gomes, Safety and Environmental Support Operations
Director for the facility. Energy reductions can lead to decreases
in the by-products of energy use that cause global warming, acid
rain, and smog—this is pollution prevention on a global scale.
While not all of Tri-Star's projects are directly transferable to
every facility, other manufacturers could use the information
gained from Tri-Star's experience to examine their own energy
and water use.
Utilizing the Utilities
Tri-Star has implemented several energy conservation projects.
The two projects described in this case study both involved
collaborative efforts with the electric and/or gas companies.
Together, these two projects have resulted in savings of
thousands of dollars per month, or about $51,800 annually.

+ Balancing airflow saved energy.

Tri-Star's first energy conservation opportunity was identified in
its fixed flow-rate air make-up units. The facility has several
pieces of equipment that exhaust air, including wet scrubbers and
an electrostatic precipitator.  To balance the air flow, Tri-Star had
been using two gas-fired air make-up units, each with a capacity
of 40,000 cubic feet per minute (cfm).  Since these operated at a
fixed rate, they were on continuously, even during non-
production hours.

In addition to the operating energy they consumed, the units also
required the air conditioning and heating systems to work
overtime. In the summer, the units blew hot, humid, air into the
facility. In the whiter, the units heated the air that was blown in.
This resulted in major temperature inconsistencies throughout the
building, with the hot air in some areas shutting down the
thermostats, making the cold areas even colder.

Working with the gas and electric companies, Tri-Star found
state-of-the-art, variable speed controllers that could be
retrofitted to the make-up air units. (With the variable speed
controllers, the flow rate is based on the air exhaust rate from the
exhausting equipment.)  Significant savings in electric and gas
bills were realized. A unique feature of this project is that it
required no capital investment; the electric and gas company
paid for the new equipment.

The facility estimates annual savings to be $22,900 on gas and
$15,600 on electricity.  Additionally, the project reduced air
pollution through energy savings of 31,000 therms and 192,800
kilowatt-hours (kWh). This translates to annual reductions of:

    • CO2 (global warming) of 289,200 pounds
    • SO2 (acid rain) of 3,000 pounds
    • NOX (acid rain and smog) of 1,100 pounds

^ Replacing compressors improved efficiency.

In another energy conservation project, Tri-Star examined its
compressed air use. The facility had been using two 100 HP and
two 50 HP compressors. These units had some trouble meeting
the demand.  With help from the "Energy Initiative" program run
by the electric company (Mass Electric) and input from a
consultant, the facility investigated its compressor situation.
Based on the results, Tri-Star:

     0 added a reserve air tank
     0 replaced the four compressors of 300 HP combined
      capacity with three 50 HP energy efficient compressors
      (150 HP combined capacity)
     0 set up the units to cycle based on the compressed air
      demand in the facility
These changes have saved energy and eliminated the problems in
meeting the facility's demand for compressed air. Annual energy
cost savings from this project are estimated to be $13,300, based
on a 164,800  kWh reduction hi electricity use. This translates to
annual reductions of:

     • CO2 (global warming) of 247,200 pounds
     • SO2 (acid rain) of 2,500 pounds
     • NOX (acid rain and smog) of 900 pounds
 Energy savings from the Tri-Star projects
 are equal to".
 Taking 50 cars off the road/year...
    tf
  ... or saving 27,000 gallons of crude oil/year

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  U.S.EPA
These energy use reduction projects have improved plant
operations, saved money, and reduced virgin oil consumption,
waste oil (hazardous waste) generation, and air pollution in the
community.

Conserving Water Pays  Off

Water conservation has been another focus area of Tri-Star's
pollution prevention efforts that goes beyond regulated materials.

^ Using DI water avoided chemical cleaners.

When Tri-Star expanded its fabrication business to add assembly
operations, the facility considered the different types of systems it
could use to clean flux residue from the wave soldering unit. It
looked into the options available in vapor degreasing and semi-
aqueous cleaning. With further investigation, Tri-Star discovered
that hot deionized (DI) water could clean the boards just as
effectively as the chemical-based cleaning systems. Then Tri-Star
went one step further and purchased a closed-loop DI water
generation system that delivers 5 to 7 gallons per minute (gpm).
The closed-loop system both generates DI water and recycles it
through the cleaning process.

One problem Tri-Star initially experienced with the system was
that solder paste was degrading the system's resin columns.  In
normal production this is not an issue; however, when a board
requires rework, the operator runs it through the closed-loop
cleaning system to remove the solder paste before reapplication.
To solve this problem, Tri-Star installed a sink on the side
cleaning unit where the operator could manually clean the reject
boards with hot DI water instead of placing them on the system
conveyor. The effluent from the sink is plumbed through a filter
and sent directly to waste treatment. With this simple installation,
the solder paste from the rejected boards never enters the closed-
loop system, extending the life of the resin columns.

Because this closed-loop system was installed for a new oper-
ation, benefits compared to other technologies  could not be
quantified. Compared to other flux residue cleaning systems, the
qualitative benefits are that it:

    • conserves water
    • does not use solvents
    • does not use any chemicals

+ Smarter rinsing reduced water use by 79%.

In another water conservation project, Tri-Star installed flow
controls on rinses, increased counterflow rinsing, and imple-
mented other "smart rinsing" techniques on its electroless copper
plating line.  By re-routing rinse water from one set of
counterflow rinse tanks to another, Tri-Star cut the incoming
water sources from seven to four, and reduced water usage on the
line from 19  gpm to 4 gpm, as shown in the chart below.

Although Tri-Star made these changes on the deposition line,
these water use reduction ideas may be applied to other processes
that use multiple rinses. To make these changes in any process,
cross-contamination issues must be carefully considered. To
Ele<
Water Use
Before "Smart
Rinsing"

3 gpm 	 ^
2 gpm 	 >~

3 gpm ^



;troless Copper Line
Process Steps Water Use
After "Smart
Rinsing"
Glass Etch
Counterflow Rinse (2X)
Sulfuric Acid Dip
Counterflow Rinse (2X)
Conditioner
Counterflow Rinse (2X)
Micro Etch
Counterflow Rinse (2X)
Predip
Activator
Counterflow Rinse (3X)
Accelerator
Counterflow Rinse (2X)
Electroless Copper
Stagnant Rinse (3X)
Sulfuric Acid Dip
Rinse
Anti-Tarnish


. ^

l^, H

u

u

l« *




19 gpm total flow 4 gpm total flow

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design the rinse water reuse for this line, Tri-Star set up criteria,
flagging "Do not contaminate" items.

   1 Do not contaminate:

    El electroless copper bath with palladium from the catalyst
    12 catalyst with cleaner/conditioner
    0 accelerator with electroless copper
    0 electroless copper with microetch or acids
    0 microetch with cleaner/conditioner
In addition to water savings, these changes also reduced the
amount of chemicals needed to maintain the process baths. With
the "smart rinsing" set-up, the chemistry is eventually dragged
back into the tank from which it was dragged out (i.e., rinse
water flows back and becomes the rinse of the previous step).
This has reduced the chemicals needed for drag-out
replenishment additions by 25% for the affected baths (microetch
and accelerator).

Overall, Tri-Star estimates that "smart rinsing" has reduced its
water usage by 2.5 million gallons per year, resulting in cost
savings of approximately $15,000. This is based on operating
the electroless copper line for 10 to 12 hours per day, 5 days per
week. The combined water and sewer fees in the facility's area
are $4.69/100 ft3 (or $6.26/1,000 gal).  Additionally, Tri-Star
saved on chemical purchases resulting from reduced chemical
use.

The Design for the Environment
Printed Wiring Board Project

Through the Design for the Environment (DfE) Printed Wiring
Board (PWB) Project, representatives of the printed wiring board
industry and other stakeholders have formed a partnership with
the U.S. Environmental Protection Agency (EPA).  This project
is a cooperative, non-regulatory effort in which EPA, industry,
and other interested parties are working together to develop tech-
nical information on pollution prevention technologies specific to
the PWB industry. This information includes comparative data
on the risks, performance, and cost of other manufacturing
options.

To date, the DfE PWB Project has focused on conducting a
comprehensive evaluation of alternative technologies for making
through-holes conductive.  The Project is also beginning to
evaluate alternatives to the hot-air-solder-leveling process. By
publishing the results of these evaluations, DfE is able to  provide
PWB  manufacturers with the information they need to make
informed business decisions that take human health and environ-
mental risk into consideration, in addition to performance and
cost. The Project is also identifying and publicizing other
pollution prevention opportunities in the industry through the
development of PWB case studies such as this one.
Acknowledgments
EPA's DfE Program would like to thank Tri-Star Technologies,
Inc., for participating in this case study, along with DfE PWB
Project participants from the following organizations who
provided advice and guidance: Circuit Center, Inc., Concurrent
Technologies Corp., Hadco Corp., Merix Corp., and the Institute
for Interconnecting and Packaging Electronic Circuits.
 Additional Pollution Prevention
 Resources for the PWB Industry

 In addition to this case study, the DfE PWB Project has prepared
 other case studies that examine pollution prevention opportunities
 for the PWB industry. All case studies are based on the experiences
 and successes of facilities in implementing pollution prevention
 projects. The other case study topics available include:

      Pollution Prevention Work Practices   -   ;.
      On-site Etchant Regeneration                 .-'""••_...
      Opportunities for Acid Recovery and Management
      Plasma Desmear
      A Continuous-flow System for Reusing Microetchant _
 These case studies and other documents published by the DfE
 Project are available from:

     Pollution Prevention Information Clearinghouse (PPIC)
     U.S. EPA                                           ~
     401 M Street, SW (7409)
     Washington, D.C. 20460     ,
     Phone: 202-260-1023 Fax: 202-260-4659        -..:
     E-mail: PPIC@epamail.epa.gov

 These documents are also available via Internet at:
     http://www.ipc.org/htmVehstypes.htniSdesign

 The DfE Program welcomes your feedback. If you have
 implemented any of the ideas in this series of PWB case studies,
 please tell us about it by calling the DfE Program, at 202-260-1678
 or by sending e-mail to:
     oppt.dfe@epamail.epa.gov
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