FINAL REPORT
CARBON BLACK
DISPERSION
PRE-PLATING
TECHNOLOGY FOR
PRINTED WIRE BOARD
MANUFACTURING
To
RISK REDUCTION ENGINEERING LABORATORY
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO
. . . Putting Technology To Work
SEPTEMBER 1993
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September 1993
CARBON BLACK DISPERSION
PRE-PLATING TECHNOLOGY
FOR PRINTED WIRE BOARD MANUFACTURING
Final Technology Evaluation Report !
by
Dale W. Folsom, Arun R. Gavaskar,
Jody A. Jones, and Robert F. Olfenbuttel
Battelle
Columbus, Ohio 43201
Contract No. 68-CO-0003
Work Assignment No. 2-36
Project Officer
Teresa Harten
Waste Minimization, Destruction, and Disposal
Research Division
Risk Reduction Engineering Laboratory
Cincinnati, Ohio 45268
RISK REDUCTION ENGINEERING LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
) Printed on Recycled Papar
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NOTICE
This material has been funded wholly or hi part by the U.S. Environmental Protection
Agency (EPA) under Contract No. 68-CO-0003 to Battelle. It has been subjected to the Agency's peer
and administrative review and approved for publication as an EPA document. Approval does not signify
that the contents necessarily reflect the views and policies of the U.S. Environmental Protection Agency
or Battelle; nor does mention of trade names or commercial products constitute endorsement or
recommendation of use. This document is intended as advisory guidance only to the electronics industry
in developing approaches to waste reduction. Compliance with environmental and occupational safety
and health laws is the responsibility of each individual business and is not the focus of this document.
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FOREWORD
Today's rapidly developing and changing technologies and industrial products and practices
frequently carry with them the increased generation of materials that, if improperly dealt with, can
threaten both public health and the environment. The U.S. Environmental Protection Agency (EPA) is
charged by Congress with protecting the Nation's land, air, and water resources. Under a mandate of
national environmental laws, the agency strives to formulate and implement actions leading to a
compatible balance between human activities and the ability of natural systems to support and nurture life.
These laws direct the EPA to perform research to define our environmental problems, measure the
impacts, and search for solutions.
The Risk Reduction Engineering Laboratory is responsible for planning, implementing, and
managing research, development, and demonstration programs to provide an authoritative, defensible
engineering basis in support of the policies, programs, and regulations of the EPA with respect to
drinking water, wastewater, pesticides, toxic substances, solid and hazardous wastes, Superfund-related
activities, and pollution prevention. This publication is one of the products of that research and provides
a vital communication link between the researcher and the user community.
Passage of the Pollution Prevention Act of 1990 marked a significant change hi U.S. policies
concerning the generation of hazardous and nonhazardous wastes.. This bill implements the national
objective of pollution prevention by establishing a source reduction program at the EPA and by assisting
states in providing information about and technical assistance for regarding source reduction. In support
of the emphasis on pollution prevention, the "Waste Reduction Innovative Technology Evaluation
(WRITE) Program" has been designed to identify, evaluate, and/or demonstrate new techniques and
technologies that lead to waste reduction. The WRITE Program emphasizes source reduction and on--site
recycling. These methods reduce or eliminate transportation, handling, treatment, and disposal of
hazardous materials in the environment. The technology evaluation project discussed in this report
describes the use of a carbon black dispersion pre-plating technology as an alternative to electroless
copper for through-hole plating during printed wire board manufacture. The carbon black pre-plating
technology reduces wastes by reducing process steps and by avoiding the use of metals and hazardous
materials.
E. Timothy Oppelt, Director
Risk Reduction Engineering Laboratory
iii ;
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ABSTRACT
,i
This evaluation addresses the product quality, waste reduction, and economic issues involved
in replacing electroless copper with a carbon black dispersion technology. McCurdy Circuits of Orange
County, California, currently has both processes in operation. McCurdy has found that the product
quality achieved with each process is equal. Sampling and analysis of the wastestreams and estimation
of bath usage through this project has determined that the carbon black dispersion produces fewer
quantities of waste. With this technology, rinse water usage is reduced from 13.8 gal per ft2 to 1.72 gal
per ft2 of printed wire board surface. The total solids contained in the rinse water is reduced from 23,800
mg/ft2 to 4,500 mg/ft2 of board surface. Carbon black dispersion also eliminates some specific hazards
resulting from the electroless copper technology, i.e., the use of formaldehyde and complexed copper.
An economic analysis determined that the new process is cost efficient due to reduced chemical usage and
a more efficient process. The payback period is less than 4 years for purchase of the system tested in
this study. The new carbon black dispersion process was found to be a viable alternative to electroless
copper. I
i
This report was submitted in partial fulfillment of Contract Number 68-CO-0003, Work
Assignment 2-36, under the sponsorship of the U.S. Environmental Protection Agency. This report
covers the period from January 1991 to September 30, 1992, and work was completed as of September
30, 1992.
IV
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CONTENTS
Page
NOTICE " u
FOREWORD iji
ABSTRACT iv
FIGURES ' ' ' ' vi
TABLES vi
ACKNOWLEDGMENTS '.'.'.'.'.'.'.'.'. vii
SECTION 1
INTRODUCTION !
GENERAL OVERVIEW .... 1. ........ 1
DESCRIPTION OF THE SITE AND TECHNOLOGY STUDIED . . ! 2
LITERATURE SURVEY 6
STATEMENT OF PROJECT OBJECTIVES .].... ..... 7
SECTION 2
CONCLUSIONS AND RECOMMENDATIONS 8
SECTION 3
METHODOLOGY n
WASTE REDUCTION POTENTIAL !!"''•" 11
ECONOMIC EVALUATION, 13
PRODUCT QUALITY '.'.'.'.'. . . ....... 13
SECTION 4
RESULTS AND DISCUSSION 14
WASTE REDUCTION ....../........ 14
Reduction in Wastewater Volume 15
Reduction in Pollutant Volume 16
ECONOMICS 23
Operating Costs 23
Return on Investment 25
QUALITY ASSURANCE 29
SECTION 5
REFERENCES 31
APPENDIX A
BLACKHOLE™ TECHNOLOGY INFORMATION 32
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CONTENTS (Continued)
LIST OF FIGURES
Page
FIGURE 1. ELECTROLESS COPPER PROCESS LINE USED FOR PRE-PLATING 3
FIGURE 2. BLACKHOLE™ TECHNOLOGY LINE USED FOR CARBON BLACK
DISPERSION PRE-PLATING ..'...; 5
I
LIST OF TABLES
TABLE 1. SUMMARY OF WASTE REDUCTION g
TABLE 2. SAMPLE SUMMARY 12
TABLE 3. BATH VOLUMES 15
TABLE 4. RINSE WATER FLOW RATES '.'.'.'.'.'. 16
TABLE 5. ANNUAL WATER USE VOLUME 17
TABLE 6. CHEMICAL USAGE '.'.'.'.'.'.'.'.'. 18
TABLE 7. ANNUAL CHEMICAL USAGE ....... 19
TABLE 8. ELECTROLESS COPPER ANALYTICAL RESULTS 21
TABLE 9. BLACKHOLE™ ANALYTICAL RESULTS 22
TABLE 10. STATISTICAL ANALYSIS OF RESULTS . ; 23
TABLE 11. CHEMICAL COSTS 24
TABLE 12. WATER USE 26
TABLE 13. MAJOR OPERATING COSTS '.'. 26
TABLE 14. CAPITAL REQUIREMENTS 27
TABLE 15. DIFFERENCE IN OPERATING COSTS 27
TABLE 16. REVENUE AND COST FACTORS '.'.'.'.'.'.'. 28
TABLE 17. RETURN ON INVESTMENT '.'.'.'.'. 28
TABLE 18. ACCURACY DATA FOR ANALYTICAL RESULTS '.'.'. 29
TABLE 19. PRECISION DATA FOR ANALYTICAL RESULTS 29
TABLE 20. FORMALDEHYDE ANALYSIS RESULTS 30
VI
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ACKNOWLEDGMENTS
The U.S. Environmental Protection Agency and Battelle wish to acknowledge the host site
for this evaluation study, McCurdy Circuits, Orange, California. McCurdy Circuits personnel Keith
Criscuiolo, Charles McLaughlin, and Fred Scheer supplied relevant process information, helped conduct
the testing, and reviewed the results of the testing. Their contributions allowed the evaluation study to
proceed smoothly.
vn
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SECTION 1
INTRODUCTION
GENERAL OVERVIEW
The objective of the U.S. Environmental Protection Agency's (EPA's) Waste Reduction
Innovative Technology Evaluation (WRITE) Program is to evaluate prototype technologies in the
workplace that have potential for reducing wastes at the source or for preventing pollution. In general,
each technology is evaluated on three issues.
First, the impact of the new technology on waste generation is measured. The new
technology will be compared to the existing technology (baseline) or the process that it replaces. The ..
waste generated from each technology is determined and the values are compared.
Second, the economics of the new technology must be quantified and compared with the
economics of the existing technology. It should be mentioned that improved economics is not the only
criterion for using a new technology. Justifications other than reduced costs would encourage
implementing new approaches or technologies. Nevertheless, a measure of the economic impact of any
potential change is useful.
Third, the effectiveness of the new technology is assessed. Waste reduction or pollution
prevention technologies typically recycle or reuse materials, or use alternative materials or techniques.
Therefore, it is important to verify whether the quality of the feed materials and the quality of the product
are acceptable for the intended purpose.
This study evaluated a process that replaces electroless copper for through-hole plating in
the manufacture of printed wire boards (PWBs). The new process uses a carbon black dispersion process
to replace the electroless copper process. The following sections provide detail on the evaluation of this
new process.
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DESCRIPTION OF THE SITE AND TECHNOLQGY STUDIED
S
McCurdy Circuits of Orange County, California, the host test site for this project, produces
PWBs at this site. One PWB manufacturing process line at McCurdy Circuits operates using electroless
copper for the through-hole plating of PWBs. This study focused on a potential replacement process for
electroless copper through-hole plating in PWB manufacturing operations.
The electroless copper process at McCurdy Circuits consists of 18 operational steps:
1. Acid cleaner
2. Rinse (to discharge line)
3. Microetch (sodium persulfate solution)
4. Rinse (to ion exchange line)
5. Activator-pre-dip
6. Catalyst
7. Rinse (to discharge line)
8. Rinse (to discharge line)
9. Accelerator
10. Rinse (to discharge line)
11. Electroless copper
12. Rinse (to separate ion exchange system)
13. Sulfuric acid 10%
14. Rinse (to ion exchange system)
15. Anti-ox
16. Rinse (to discharge line)
17. Deionized (D.I.) water rinse (to discharge line)
18. Forced air dry
In the first 17 steps, racks of PWBs are moved from tank to tank with an automated hoist.
The sequence is shown in Figure 1. All the rinses are single flow through, which generates more
wastewater than cascading or multiple-use rinses. The rinses following the electroless copper bath
(Step 11) receive complexed copper from the bath due to drag out. This complexed copper, which is
discharged with the rinse water, is hard to treat by typical metal hydroxide precipitation. The electroless
copper process line rinse water is collected in one of three drain lines, as shown in Figure 1. One drain
line goes to a discharge line (Sampling Point #1), one goes to the first ion exchange collection system
(beyond Sampling Point #2), and one goes to an ion exchange system for the electroless copper rinse
(Sampling Point #3).
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The carbon black dispersion pre-plating process being evaluated in this study replaces the
electroless copper process used for through-hole plating. Whereas the electroless copper process is
essentially a batch process, the carbon black process is a continuous system hi which parts are placed on
a conveyor belt and run through as often as needed. This carbon black dispersion technology, termed
BLACKHOLE™ Technology by the vendor who invented it, consists of fewer baths and a more simplified
process with only 11 process steps:
1. BLACKHOLE™ cleaner
2. Rinse (water from step 4, to discharge line)
3. BLACKHOLE™ conditioner j
4. Rinse (fresh tap water, to rinse #2)
5. BLACKHOLE™ bath
6. Dryer
7. Microetch
8. Rinse (water from step 10, to ion exchange system)
9. Anti-tarnish \
10. Rinse (fresh tap water) ;
11. Dry
Figure 2 shows the progression of steps 1 through 10. The BLACKHOLE™ bath (Step 5) is an aqueous
carbon black dispersion, which eliminates the need for electroless copper metallization prior to electrolytic
plating. The steps prior to and following Step 5 are similar to those used hi the electroless copper
process. The vendor literature provided hi Appendix A more fully describes the process steps.
When using the BLACKHOLE™ Technology, Steps 1 through 6 are performed sequentially.
Then these steps are repeated without the cleaner step (Step 1) to provide extended exposure to the carbon
black suspension solution in the BLACKHOLE™ bath (Step 5), followed by Steps 7 through 12,
performed sequentially. These steps are done automatically hi a horizontal conveyor system at McCurdy
Circuits, as shown in Figure 2. Repetition of the first part of the sequence was deemed necessary to
increase the treatment tune hi the BLACKHOLE™ process bath because the equipment at McCurdy
Circuits is an early version. Current equipment is designed to provide a longer treatment tune, thus
eliminating the need to repeat steps 1 through 6. Unlike the electroless copper process, with
BLACKHOLE™ Technology the rinse after the microetch process step is the only rinse water stream that
goes to the commingled ion exchange system (beyond Sampling Point 5) that is shared with the first ion
exchange system for the electroless copper process, the rest goes to the discharge line.
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Wastewater is treated at McCurdy Circuits by means of two ion exchange systems that
collect copper from the rinse water. The first (commingled) ion exchange system is for copper-containing
rinse waters from both processes, whereas the other ion exchange system is for the complexed copper
from the rinse following the electroless copper bath. The regenerant solution from the commingled ion
exchange system is passed through an electrowinning system to plate out copper for sale as scrap. After
that, it is treated again to precipitate out residual metals. Upon filtration, these precipitated metals form
a cake that is placed in drums and shipped out for disposal.
The carbon black dispersion process has fewer processing steps than the electroless copper
process. Carbon black dispersion uses only two rinse water flows, and the process solutions contain
nonhazardous materials. During the McCurdy Circuits evaluation, the carbon black dispersion process
was operated side-by-side with the electroless copper process for comparison.
LITERATURE SURVEY i
The carbon black dispersion process has been available commercially since 1989. Military
Standard MIL-P-55110D permits through-hole plating technologies other than electroless copper, and the
BLACKHOLE™ Technology process is one alternative accepted under this Military Standard. This
military standard for PWBs establishes the qualification and performance requirements for rigid single-
sided PWBs, rigid double-side PWBs, and rigid multi-layer PWBs with plated through-holes.
The literature search done in conjunction with this study turned up three published papers
(Bracht and Piano, 1990; Murray, Sept. 1989; Murray, Dec. 1989) and three technical papers. The first
technical paper (Marien and Pendleton, nd), presented at the 5th Printed Circuit World Convention, dealt
with "Plating-Through-Hole Colloid and Surface Phenomena." The paper describes some surface and
colloid phenomena occurring during through-hole surface preparation. It examines the choice of epoxy
resin smear removal chemistry and the change in density needed to achieve optimum coating of the
carbon black dispersion in the through-hole.
The second technical paper (Polakovic, 1988) describes and evaluates the BLACKHOLE™
process. The evaluation includes test results. The third technical paper (Greenberg, 1988) updates
Polakovic's paper. Greenberg compares BLACKHOLE™ Technology to the electroless copper process
and details the technology's progress with regard to practical aspects of surface treatment.
The Bracht and Piano article in Printed Circuit Fabrication considers the environmental
advantages of the BLACKHOLE™ Technology. :
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One of Murray's articles in Circuits Manufacturing (1989b) discusses various methods for
plating small holes (which are typically difficult to plate). In the discussion of the BLACKHOLE™
process, Murray concludes that BLACKHOLE™ is successful because it lays a better base for electrolytic
plating than does electroless copper. Murray also states that, with the addition of the new process, Mario
Circuits has obtained a 30% reduction hi wastewater treatment costs and a faster delivery of higher
quality parts. The other article by Murray (1989a) focused on applications of the BLACKHOLE™
process at several manufacturers. Murray talked to engineers at Circuit Technology who decided to
install a BLACKHOLE™ production line after being impressed by a trial period that resulted hi a drop
in waste treatment, excellent yields, and an increase in throughput. Several other satisfied customers
were cited, including McCurdy Circuits.
Two indirectly related articles (Metzger et al., 1990; Nakahara, 1992) describe an alternative
process to electroless copper — the "direct metallization system" (DMS). This process uses conductive
organic polymers to provide a good basis for copper adhesion.
STATEMENT OF PROJECT OBJECTIVES
The goal of this study was to compare the wastes generated from the carbon black dispersion
process using BLACKHOLE™ Technology with those generated in using the electroless copper process
in PWB production. This study had two major objectives:
I
• Evaluate the waste reduction potential of the carbon black dispersion
technology. , ;
• Evaluate the cost effectiveness of the carbon black dispersion technology
compared to that of the electroless copper process.
The focus of the study was waste reduction and economics. Product quality was a secondary issue. The
study used McCurdy Circuits and their customers' acceptance of the PWBs as evidence of the product
quality and acceptance.
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SECTION!
CONCLUSIONS AND RECOMMENDATIONS
i
I
The main focus of this study was the waste reduction potential of the carbon black dispersion
process using the BLACKHOLE™ Technology. The carbon black dispersion process achieved waste
reduction through the reduced number of process steps and the reduced hazard of the chemicals used in
the process. Table 1 summarizes the waste reduction achieved during this process evaluation. Rinse
water use was reduced by a factor of eight, from 13.8 gal/ft2 of PWB to 1.72 gal/ft2. Chemical usage
dropped considerably for the carbon black dispersion process. Although the exact chemicals and compo-
sitions are different for each process such that direct comparisons cannot be made, some of the bath com-
positions are similar. For example, the cleaner used in each process (monoethanolamine) is reduced from
150.5 gal/yr using the electroless copper process to 21,4 gal/yr using the carbon black dispersion process.
i
Copper waste in the rinse water is reduced 23% using carbon black dispersion. This does
not take into account the copper lost due to replacement of the electroless copper solution. Each day,
20% of the 100-gallon electroless copper bath is replaced. A copper solution concentration of 2 grams
per liter removed from the bath results in a loss of 83.4 pounds per year of copper based on a 50-week
TABLE 1. SUMMARY OF WASTE REDUCTION
Waste Types
Rinse Water
Electroless
Copper Process
13.8 gal/ft2
BLACKHOLE™
Process
L7 gal/ft2
Net Change
in Waste
12.2 eal/ft2
Chemical Usage
(Section 4)
11,755 gal + 38 Ibs 90 gal + 611 Ibs not calculable
Copper Waste
(in rinse water)
Total Solids
324 mg/ft2
23,800 mg/ft2
248 mg/ft2
1
i
4,510 mg/ft2
76 mg/ft2
19,300 mg/ft2
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year. The copper found in the carbon black dispersion rinse water is removed from the PWBs themselves
during microetching. No additional copper is introduced in the carbon black dispersion baths during
processing.
The quantity of total solids leaving with the rinse water is reduced by a factor of five using
the carbon black dispersion process. The reduction in solids results from the reduced use of rinse water
and the fewer number of process baths used by the carbon black dispersion process. The reduced solids
indicate that fewer bath chemicals are lost and that fewer chemicals are discharged to the wastewater
treatment system.
The carbon black dispersion process uses five chemical process baths and four rinse baths.
The chemical process baths avoid the introduction of hazardous metals and materials. Chemical baths
in the electroless copper process contain the metals palladium and copper, and formaldehyde (Section 4).
The carbon black dispersion process eliminates the use of both palladium, which is the catalyst used in
the electroless copper process, and formaldehyde, a significant health hazard.
Table 1 does not include the waste generated during ion exchange. McCurdy Circuits
periodically replaces ion exchange columns. These have a small impact on the overall system.
In addition to the long-term environmental aspects of waste reduction using carbon black
dispersion, the hazard reduction of this process has immediate advantages. Eliminating the use; of
formaldehyde diminishes the health risks to the personnel involved in handling the baths, as well as the
industry's potential environmental liabilities. Fewer regulations may be imposed on the PWB industry
because of the reduced hazard. The reduced number of process steps and quantities of chemicals used
also reduces storage and transportation requirements, thus minimizing the possibility of leaks and
accidental spills during storage and transportation. These same factors also result in economic savings
that are too varied and intangible to be included in the analysis of economic factors during this study.
The economic analysis of this study showed the carbon black dispersion process using
BLACKHOLE™ Technology to be cost effective. Section 4 compares the operating costs of the two
evaluated processes. Carbon black dispersion has an annual operating cost of approximately half that of
the electroless copper process. A continuous horizontal carbon black dispersion process line that can
process 50 to 100 PWBs per hour costs approximately $200,000 to purchase. Combining this with
operating savings detailed in Section 4 provides a payback period of less than 4 years if the cost of capital
is assumed to be 15%. The option of converting electroless copper equipment to the carbon black
dispersion process would reduce the capital cost and result in an even faster payback period.
The energy costs of using both process lines were assumed to be almost equal. There was
no readily available method to determine the energy usage of each line. Both lines have heated bams,
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equipment conveyors, and driers. The difference in energy usage between the two lines should not
significantly affect the economics.
The actual waste treatment costs at the test site were unavailable. In both processes
performed at McCurdy Circuits, copper-containing wastewater is passed through an ion exchange resin
to remove the copper before entering the discharge line. The copper is eluted from the resin and
recovered by electrowinning. The copper is then given away as scrap. A plant that operates a
!
conventional wastewater treatment system consisting of pH adjustment and precipitation would realize a
significant savings in treatment costs with the carbon black process because of the reduction in copper
waste. This option was not included hi our evaluation.
Product quality, as determined by an inventory of rejects during the study at McCurdy
Circuits, was similar to that of the electroless copper process. The carbon black dispersion process
achieved an acceptable product. PWBs processed by carbon black dispersion using the BLACKHOLE™
Technology have also passed MDL-STD-55110D qualification and performance standards for plated
through-holes. ;
In conclusion, the carbon black dispersion process reduces wastes, avoids many hazardous
chemicals and metals, is cost effective, and yields an acceptable product. Therefore, this process should
be considered a viable alternative to the electroless copper process. If the shop involved is a job shop,
client input and requirements would be important in determining the feasibility of incorporating the
carbon black dispersion process. This report presents the waste reduction potential and economic savings
of carbon black dispersion using the BLACKHOLE™ Technology for McCurdy Circuits. Although this
report can provide generalizations for other companies, it is recommended that each company examine
the specific requirements and the suitability of using carbon black dispersion for its particular needs.
10;
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SECTION 3
METHODOLOGY
WASTE REDUCTION POTENTIAL
The amount of waste resulting from the electroless copper operation, run at fall production,
was evaluated to represent baseline data. The amount of waste from the carbon black dispersion process
using BLACKHOLE™ Technology, run at fall capacity, was then compared to this baseline. The
wastestreams from both processes consisted of the bath solutions (discarded periodically) and the rinse
water. The volumes of these wastestreams were obtained from plant records (bath volumes) and field
measurements (rinse water flow). Bath composition is known and maintained by McCurdy Circuits. The
pollutant content of the bath solutions was estimated from plant records of the chemical makeup of the
baths. The pollutant content of the rinse water was obtained by analysis of samples collected during field
testing. Measurable factors in analyses to characterize the rinse water included copper, pH, and total
solids content.
Samples from both processes were obtained to analyze the pollutants in the rinse water. Six
sample sets for the electroless copper line and 11 sample sets for the carbon black dispersion process line
were taken over 3 to 4 days of operations. Composite samples were required to allow for the cyclic
concentration swings of the rinse water due to batch rinsing operations of the racks used hi the electroless
copper line. The composite samples were taken by a small metering pump that pulled a continuous
sample of the rinse water as it left the process line. The sampling point was hi the drain line after the
rinse water had been well mixed but before other water sources had been added. The electroless copper
process has three drain lines, and the carbon black process has two drain lines. Because electroless
copper is basically a batch process, a composite sample was taken that would cover five cycles, or
90 minutes. On the other hand, the carbon black process is continuous and reaches steady state rather
quickly. It has little variability because it is not done in batches. Therefore the sampling tune was 10
minutes. Table 2 lists the samples from each drain line.
The sampling system for obtaining composite samples was flushed with clean water between
samples to avoid contamination. The sampler also was operated for 5 minutes before any sample was
11
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collected to flush out both water from the sampling system and materials introduced during placement
of the sampling line into the process drain line. ;
TABLE 2. SAMPLE SUMMARY
Sample Location
BLACKHOLE™
Discharge Line
Ion Exchange Line
Sample Number
EC-4I, EC-5I, EC-6I
BH-1S, BH-2S, BH-3S
...BH-11S
BH-4I, BH-5I, BH-9I,
BH-10I, BH-11I
Sampling Tune
lOMin
lOMin
Electroless Copper (EC)
Discharge Line
Complexed
Ion Exchange Line
Ion Exchange Line
i
I
EC-IS, EC-2S, EC-3S,
EC-4S, EC-5S, EC-6S
EC-1C, EC-2C, EC-3C
EC-4C, EC-5C, EC-6C
EC-1I, EC-2I, EC-3I,
90Min
90Min
90Min
All containers were prewashed before use, per Standard Method 1070. The bottles were
labeled and placed in a cooler in the field for transportation to the laboratory. The bottles, if glass, were
wrapped in bubble wrap to prevent breakage. The samples were packed in ice. The sample cooler was
then labeled and shipped out via Federal Express to the laboratory with a chain-of-custody form.
The analytical methods used for this study are all published standard methods. The copper
content in rinse water was measured using inductively coupled plasma spectrometry or equivalent by EPA
Method 200.7. Total solids were measured by EPA Method 160.2. Only pH measurements were taken
in the field (by EPA Method 150.1), so the pH meter was the only analytical instrument that needed to
be calibrated in the field. Calibration solutions were taken for daily field calibration. A backup meter
also was taken to the test site. .
The rinse water flow rates of the two processes were determined, using the rinse tank as
a receiving vessel. A stopwatch was used to measure the tune required to raise the water level by
2 inches after the rinse tank outlet had been plugged. The rinse water flows were controlled either by
restricting the flow orifices that maintained a constant flow of water to each rinse tank over time, or by
a manually set ball valve. The flow remained constant so long as the city water pressure was consistent.
12
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The city water pressure was not expected to vary significantly over the sampling time period, but if it
did, it affected both lines equally. The flow to each rinse tank in the process was totaled for the total
rinse water flow for the process. This flow and the material concentrations were used to determine the
quantity of waste discharged from each process in the rinse water.
ECONOMIC EVALUATION
The economic evaluation was based on data obtained from McCurdy Circuits, including
chemical costs and amounts used, and the cost and amount of water used. The current capital cost of
carbon black dispersion equipment was obtained from an equipment vendor. The economic data were
processed through an economics program based on worksheets provided in the Facility Pollution
Prevention Guide (EPA, 1992) and modified to fit the project. This program includes taxes, inflation,
depreciation, and cost of capital. (Cost of capital is the amount of interest the firm could have made if
the capital cost of equipment were otherwise invested.) The program output projected a year-by-year
return on investment.
PRODUCT QUALITY
The performance of the carbon black dispersion process using BLACKHOLE™ Technology
in meeting product quality and performance was based on results of previous tests done in accordance
with the Military Standard MIL-P-55110D requirements for through-hole plating. No additional testing
was conducted during this evaluation, because the tests involved destructive testing of a number of PWBs
and were time-consuming. McCurdy Circuits routinely conducts their own internal quality checks of 10%
of the PWBs. During these checks, small coupons are punched from selected PWBs, cast in resin, and
polished to allow visual inspection of through-hole plating and layer bonding. Also, the PWBs are placed
on a test grid that checks continuity of the circuits. These quality checks made by McCurdy Circuits and
inspections by their clients provided verification of product quality.
13
-------
SECTION 4
RESULTS AND DISCUSSION
i
WASTE REDUCTION
The waste reduction assessment found that the production rate on the carbon black dispersion
process line using BLACKHOLE™ (BH) Technology, i.e., 3.3 ft2/min, is 2.1 times as fast as the
production rate on the electroless copper (EC) process line, i.e., 1.6 ftVmin. Production rates were timed
during the field testing and compared to production schedules maintained by McCurdy Circuits. The
production rate of 8 hrs/day, 5 days/wk, for 50 wks/yr assumed for this study is the approximate rate
at McCurdy Circuits. McCurdy Circuits operates the electroless copper process at approximately fall
capacity of 1.6 ft2/min, which yields 200,000 ft2/yr. The carbon black process line was installed in
response to increased demand, but it is not yet accepted by all clients, and thus is not operated at fall
capacity. In fact, it is operated at about 11% of its capacity. Equivalent productions must be used to
compare the waste types and quantities generated by both processes. In this study, it was assumed that
the carbon black process could completely replace the electroless copper process. Therefore, the waste
reduction numbers reflect the potential production of the carbon black process at McCurdy Circuits, not
the actual production. The calculations described below are based on the wastes that would be generated
if each process were operated at capacity for 1 year and then an adjusted total for the carbon black
process. The total is adjusted to account for the fact that the carbon black process would have processed
twice the number of PWBs as the electroless copper process. In this way, wastes generated can be
compared for equivalent annual productions. i
The waste reduction potential of the carbon black process is twofold. First, the volume of
wastewater is reduced. Less water wasted means less water that must be treated both before and after
use, saving both resources and treatment chemicals. Second, the pollutant volume is reduced. A lower
pollutant load not only requires less treatment, it also reduces the potential risk to both employees and
the environment.
14
-------
Reduction in Wastewater Volume
i
To determine the reduction in wastewater volume, both the continuous rinse water volumes
and the volumes of discarded bath solutions must be measured. The bath volumes in the electroless
copper (EC) and BLACKHOLE™ (BH) processes were obtained from plant records and confirmed by
dimensional measurements. Table 3 lists these bath volumes and shows how often each bath is com-
pletely changed. Table 4 presents the rinse water flow rates for the EC and BH processes, as measured
during the field visit. The flow rates from rinse tanks 8 (6.0 gpm) and 10 (4.6 gpm) using the EC pro-
cess were higher than usual at the time of testing. Because these rates are not often adjusted, they were
assumed to be accurate. However, McCurdy Circuits prefers to run these rinses at approximately 2 gpm.
If the lower rate were assumed, the volume reduction and economic impact would be slightly lower (i.e.,
82% water volume reduction instead of 87%, with no noticeable change hi return on investment).
Table 5 shows the annual water use for each process, assuming 8 hr/day of operation,
5 days/wk, for 50 wk/yr. Table 5 includes the water used for bath makeup, which occurs weekly for
TABLES. BATH VOLUMES
Description
Electroless Copper
Acid Cleaner
Microetch
Activator
Catalyst
Accelerator
EC
Sulfuric Acid
Anti-Ox
BLACKHOLE"
Cleaner
Conditioner
BLACKHOLE™
Microetch
Anti-Tarnish
Volume
(gal) ,
50
50
50
50
50
100
50
50
25
25
50
50
25
Replacement
Frequency
weekly
weekly ;
weekly '<
(a)
weekly
(b)
weekly
weekly
biweekly
biweekly
(a)
biweekly
biweekly .
(a) The bath is not discarded, only replenished, as shown in Table 6.
(b) -20% discarded daily (the equivalent of 100% replacement in 5 days).
15
-------
TABLE 4. RINSE WATER FLOW RATES
Electroless Copper
BLACKHOLE™
Rinse Tank
Number
2(a)
4
7
8
10
12
14
16
Total
2»>
8
Total
Flow Rate
(gpm)
i
2.5
0.9
1.4
6.0
4.6
1.6
1.5
3,8
22.3
2.9
2.6
5.5
Destination
To discharge line
To ion exchange
To discharge line
To discharge line
To discharge line
To complexed ion exchange
To ion exchange
To discharge line
To discharge line
To ion exchange
(a) Numbers hi this column refer to steps hi Figure 1.
*® Numbers hi this column refer to steps hi Figure 2.
most baths (see Table 3). As seen hi this table, the BH process uses much less water compared to the
EC process. These water volume figures indicate that a smaller quantity of wastewater treatment
chemicals would be needed, because less wastewater would be generated.
Reduction in Pollutant Volume i
To determine the reduction in pollutants in the wastestream, pollutant levels in the baths,
the solution discard rate, and the mass flow of pollutants hi the rinse water must be measured. Table 6
lists the chemical makeup of each bath in the EC and BH processes derived from plant and supplier records.
Also shown is the bath life and the amount of each chemical added to the bath throughout the week.
The annual usage (50 weeks) of each chemical shown hi Table 7 is based on the data from
Table 6. The annual numbers are then adjusted for the different production rates on each line. As seen
in Table 7, the overall chemical usage is much lower in the BH process than in the EC process.
16
-------
TABLE 5. ANNUAL WATER USE VOLUME
Description
Electroless Copper
Acid Cleaner
Microetch
Activator
Catalyst
Accelerator
EC
Sulfuric Acid
Anti-Ox
Rinses
Total
BLACKHOLE™
Cleaner
Conditioner
BLACKHOLE™
Microetch
Anti-Tarnish
Rinses
Total
Adjusted Total*)
Annual Volume(a) (gallons)
2,500
2,500
2,500
N/A
2,500
N/A
2,500
2,500
2,680,000
2,695,000
625
625
N/A
1,250
625
670,000
673,000
336,000
w Annual volumes obtained from bath volume (Table 3)
multiplied by dumping frequency and total rinse water flow
rates (from Table 4) x 60 min/hr x 8 hr/day x 5 day/wk
x 50 wk/yr.
(b) Adjusted to the same annual production as the electroless
copper process line.
However, an exact comparison cannot be established due to the different chemicals used in each process.
Although a general idea of the hazard of each chemical is known from their respective Material Safety
Data Sheets (MSDSs), the proprietary nature of the formulations makes a compouhd-by-compound
assessment difficult.
One chemical compound, formaldehyde, is completely eliminated from use by switching to
the BH process. As seen in Tables 6 and 7, formaldehyde is not present hi any of the BH process
formulations, but approximately 200 gallons per year are used in the electroless copper bath (Table 7).
17
-------
TABLE 6. CHEMICAL USAGE
Description
Electroless Copper
Acid Cleaner
Microetch
Sulfuric Acid
Sodium Persulfate
Activator
Catalyst
Pre-dip
Catalyst
Accelerator
EC
Copper
Sodium Hydroxide
Formaldehyde
Sulfuric Acid
Anti-Ox
BLACKHOLE™
Cleaner
Conditioner
BLACKHOLE™
Microetch
Sodium Persulfate
Sulfuric Acid
Copper Sulfate
Anti-Tarnish
CTCS 501
Sulfuric Acid
Initial Makeup of
Bath
2.5 gal ;
0.75 gal
37.5 Ibs
50 gal
48.5 gal ;
1.5 gal
5.0 gal
1
300 g
1,000 g
0.25 gal ;
5 gal ;
25 gal
•
0.634 gal ,
1.27 gal :
50 gal ;
45 Ibs
0.528 gal :
2 Ibs ;
0.264 gal ;
0.132 gal
Total Addition
Throughout Week
(Avg.)*)
0.394 gal
3.88 gal
0
0
0.317 gal
0.435 gal
2.86 gal
78.9 gal
45.0 gal
3.97 gal
1.16 gal
0
0.507 gal
0.193 gal
1.36 gal
0
0
0
0
0
Bath Life
1 Week
IWeek
1 Week
Indefmite(c)
1 Week
Indefmite(c)
1 Week
1 Week
2 Weeks
2 Weeks
Indefmite(c)
2 Weeks
2 Weeks
(a) From McCurdy Circuits Operations Manual.
(b) Data obtained from bath additions made during test week at McCurdy Circuits. In the case of the
BLACKHOLE™ process, the original data were modified to reflect amounts that would have been
added if the process were operated at the same capacity as the electroless copper line.
Baths are not discarded. For the catalyst, addition is to make up for drag out; for EC, it is make-
up for daily purge of 20% of the bath solution.
(c)
18
-------
TABLE 7. ANNUAL CHEMICAL USAGE(a)
Description
Electroless Copper
Acid Cleaner
Microetch
Sulfuric Acid
Sodium Persulfate
Activator
Catalyst
Pre-dip
Catalyst
Accelerator
EC
Copper
Sodium Hydroxide
Formaldehyde
Sulfuric Acid
Anti-Ox
BLACKHOLE™
Cleaner
Conditioner
BLACKHOLE™
Microetch
Sodium Persulfate
Sulfuric Acid
Copper Sulfate
Anti-Tarnish
CTCS 501
Sulfuric Acid
Annual Chemical
Usage
145 gal
195 gal
1,880 Ibs
2,500 gal
15.9 gal
21.8 gal
393 gal
3,950 gal
2,250 gal
199 gal
308 gal
1,250 gal
41.2 gal
41 .4 gal
68.0 gal
1,130 Ibs
13.2 gal
50.0 Ibs
6.60 gal
3.30 gal
Annual Usage
(Adjusted),
145 gal '
195 gal
1,880 Ibs
2,500 gal
15.9 gal
21.8 gal :
393 gal
3,950 gal
2,250 gal
199 gal
308 gal
1,250 gal
j
20.6 gal
20.7 gal ;
34.0 gal ;
585 Ibs
6.6 gal
25.0 Ibs
3.30 gal
1.65 gal
(a) Annual usage based on (50 wk/bath life in weeks) (initial makeup
+ weekly additions).
19
-------
Formaldehyde is a suspected human carcinogen that poses a significant health hazard when inhaled or
ingested or through direct physical contact. Among other health problems, it can cause difficulty hi
breathing, pulmonary tract injury, severe abdominal pain, and even death. Palladium and trace amounts
of cyanide, also used hi the electroless copper process, are not present in the carbon black dispersion
process.
Tables 8 and 9 show the results of the rinse water sample analyses from the electroless
copper process and BLACKHOLE™ process, respectively. These samples were collected during field
testing. Before being compared, the data must be normalized to account for the different flow rates hi
each rinse and for the difference hi production rates. To obtain numbers for comparison, the
i
concentrations hi milligrams per liter were first multiplied by the respective flow rates and converted to
milligrams per minute, thus adjusting them for the varying flow rates. The milligrams per minute
numbers were then added to obtain totals for each process. For BLACKHOLE™ (Table 9),
i
(2.53 mg/L X 2.9 gpm X 3.785 L/gal) + (62.3 mg/L X 2.6 gpm X 3.785 L/gal) = 641 rag/min)
i
These totals are then divided by the production rates (641 mg/min / 3.3 ft2/mih = 194 mg/ft2) to obtain
the milligrams of pollutant per feet square of PWB processed. These milligrams per feet squared
numbers, shown hi the right-hand columns of Tables 8 and 9, are now comparable quantities.
Averages and standard deviations, shown hi Table 10, were calculated, and a Student's t-test
was performed with a 95% level of confidence. The test statistic, which takes into account the standard
deviations, indicates that the levels of both copper and total solids discharged by the BH process are
significantly lower than those for the EC process. The average reduction hi copper is 76 mg/ft2, a
reduction of 23%. The average reduction hi total solids is 19,300 mg/ft2, a reduction of 81%.
The BH process thus releases significantly less copper into the wastestream. If approxi-
mately 200,000 ft2 of PWB (the operating capacity of the EC process) were run on both processes, the
reduction in copper waste would average 15.2 kg (33.4 Ib) per year.
The lower total solids discharge when using the BH process results from fewer chemical
process baths and a faster production rate. Although the higher solids composition of the BH baths would
lead one to expect that the BH process would discharge more solids, a faster production rate and fewer
process baths containing chemicals apparently offset this effect when the data are normalized.
20
-------
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21
-------
TABLE 9. BLACKHOLE™ ANALYTICAL RESULTS
Composite
taken over 10-
minute period
Sample No.
BH-1
BH-2
BH-3
BH-4
BH-5
BH-6
BH-7
BH-8
BH-9
BH-10
BH-11
Blank 1
Blank 2
Results
Average
Std. dev.
Discharge Line
(2.9 gpm)
Total
Solids
mg/L^
0
0
68
0
0
0
44
1,100
860
868
790
988
716
Total
Solids
mg/L
418
462
pH
S.U/C>
8.45
8.66
8.78
8.50
8.66
8.58
8.64
8.75
8.45
8.44
8.61
7.42
7.72
pH
S.U.
8.44
0.40
Copper
mg/L(d)
2.85
3.99
3.22
2.53
2.89
2.73
4.10
4.21
2.15
3.31
3.34
0.06
0.014
Copper
mg/L
2.72
1.34
Ion Exchange
(2.6 gpm)
Total
Solids
mg/L
I
\
160
268
',
i
1,440
1,540
1,340
i
Total
Solids
mg/L
949
675
PH
S.U.
6.20
5.89
5.32
5.25
5.78
PH
S.U.
5.69
0.40
Copper
mg/L
62.3
80.3
82.6
90.0
84.2
Copper
mg/L
79.9
10.5
Totals^)
Total
Solids
mg/ft2
477
799
7,160
7,470
6,620
Total
Solids
mg/ft2
4,510
3,540
Copper
mg/ft2
194
249
253
279
262
Copper
mg/ft2
248
32.1
(a) Total pollutant per ft2 calculated from [(discharge line flow, 2.9 gpm) (3.785 1/gal) (pollutant
cone, in discharge line, mg/L) + (ion exchange flow, 2.6 gpm) (3.785 L/gal) (pollutant cone.
in line to ion exchange, mg/L)]/the processing rate, ft2/min.
^ Total solids were measured using EPA Method 160.2.
(c) pH was measured using EPA Method 150.1; S.U. = standard unit.
(d) Copper was measured using EPA Method 200.71
22;
-------
TABLE 10. STATISTICAL ANALYSIS OF RESULTS
EC Process
BH Process
Difference in Averages(a)
% Reduction in Averages
Test Statistic
Effect of BH Process^
Average
Std. dev.
Average
Std. dev.
t-value
—
Total Solids
mg/ft2
23,800
22,800
4,510
3,540
19,300
81%
1.85
Significant
decrease
Copper
mg/ft2
324
73.6
248
32.1
76
23%
2.14
Significant
decrease
(a) The differences shown are median values.
W Based on level of significance of 0.05 (i.e., a 90% confidence level), t-values
are compared to a t critical of 1.833. This analysis takes into account the
standard deviations.
ECONOMICS
The economic assessment shows the costs for replacing the original electroless copper
system with the new carbon black dispersion system and is based on operating costs, return on investment
(ROI), and payback period. The calculations are based on the production rate of 200,000 ft2 of FSVB
per year, which is approximately the rate of the current electroless copper system. The BH process cost
basis is half a year, running at capacity, i.e., the tune it would take to process approximately 200,000' ft2
ofPWB.
Operating Costs
Operating costs include costs for labor, chemicals, water, maintenance, and waste treat-
ment/disposal.
• Labor costs for EC are based on 1 operator working for 2,000 hr at an;
estimated rate of $25/hr; for BH the basis is 1,000 hr at $25/hr.
• Chemical costs for EC and BH are shown in Table 11. Unit costs were
obtained from plant records or the suppliers.
23
-------
TABLE 11. CHEMICAL COSTS
Description
Electroless Copper
Acid Cleaner
Microetch
Sulfuric Acid
Sodium Persulfate
Activator
Catalyst
Pre-dip
Catalyst
Accelerator
EC
Copper
Sodium Hydroxide
Formaldehyde
Sulfuric Acid
Anti-Ox
Total
BLACKHOLE"
Cleaner
Conditioner
BLACKHOLE**
Microetch
Sodium Persulfate
Sulfuric Acid
Copper Sulfate
Anti-Tarnish
CTCS 501
Sulfuric Acid
Total
Annual
Chemical
Usage (gal)
145
195
1,880 Ibs
2,500
15.9
21.8
393
3,950
2,250
199
308
1,250
41.2
41.4
68.0
1,130 Ib
13.2
50.0 Ibs
6.60
3.30
j Unit
Cost
($/gal)C»
21.70
0.08
1.00 per Ib
; 3.35
: 3.35
: 280
18.65
E
10.35
2.50
6.20
0.08
; 11.95
!
> 400
400
; 595
; 1.00
; 0.08
; 6.62
i
'• 12.00
0.08
i
Cost
($/year)
3,150
15.6
1,880
8,380
53.3
6,100
7,330
40,900
5,630
1,230
24.6
14,900
16,500
16,600
40,500
1,130
1.06
331
79.2
0.26
Adjusted
Annual Cost
($/year)(c>
3,150
15.6
1,880
8,380
53.3
6,100
7,330
40,900
5,630
1,230
24.6
14,900
89,600
8,250
8,280
20,250
565
0.53
166
39.6
0.13
$37,500
(a> From Table 7.
(b)
(e)
McCurdy Circuits provided data.
Because the BLACKHOLE™ process has a production rate approximately twice that of the
electroless copper process, costs will be adjusted to compare l/t year of processing for
BLACKHOLE™ to a full year for electroless copper.
24
-------
• Water costs are based on the water requirements for EC and BH presented in
Table 12. McCurdy pays $1.20/1,000 gal for tap water and $24.53/1,000 gal
for deionized water.
• No significant difference in energy or maintenance costs was assumed.
• No significant difference in waste treatment/disposal costs between the two
processes was assumed.
• Waste treatment labor for the electroless copper process was based on 8 hours
per week at $25/hr. According to the McCurdy personnel, the
BLACKHOLE™ process requires Va of the labor of the electroless copper
process.
Table 13 summarizes the major operating costs as obtained above. As seen hi Table 13, BH has lower
operating costs than EC hi all cost categories that could be obtained from company data. The major savings
accrue through lower chemical and labor (time) costs, and the total savings add up to more than 50%.
Return on Investment
BH equipment with the capacity of the system tested at McCurdy Circuits currently costs $212,000
(1992 $$), with an estimated installation cost of $9,000. These and other cost assumptions are included
in the economics worksheet tables (Tables 14-16). The costs associated with replacing the original system
with the new carbon black system are based on the differences hi costs between the two systems or the
"extra" cost (or sayings) to operate the new system. It is assumed that the new system would be used
at capacity to replace the old electroless copper system. Therefore, the economic analysis shown is not
representative of that of McCurdy Circuits, where the new system is as yet only operating at about 10%
capacity. The capital costs included hi the analysis are higher than those of McCurdy Circuits, because
theirs was purchased several years ago under testing conditions. The costs reflected in this analysis are
i
more tjrpical of what a new user today might expect to pay.
Table 14 shows the capital cost inputs and outputs used for the return-on-investment calculations.
In this table, the tax rate, depreciation, and loan information are assumed based on industry averages.
Table 15 presents the numbers used for operating cost calculations that were discussed hi the previous
section. Table 16 reviews the revenues and cost factors, and details the yearly savings hi using the
BLACKHOLE™ Technology. Table 17 details return on investment, showing that, witfran assumed cost
of capital of 15%, the payback period is less than 4 years.
25
-------
TABLE 12. WATER USE
Description
Electroless Copper
Acid Cleaner
Microetch
Accelerator
Sulfuric acid
Anti-Ox
Rinses
Totals
Tap Water
! (gal)
0
0
1 0
0
0
2,670,000
2,670,000
D.I. water
(gal)
2500
2500
2500
2500
2500
8,000
20,500
BLACKHOLE™ |
Cleaner 0 625
Conditioner ' 0 625
Microetch 0 1,250
• Anti-Tarnish 0 625
Rinses !670,000 0
Totals 670,000 3,125
Adjusted Totals® 336.000 1,560
(a) The BLACKHOLE™ production rate is approximately twice as fast as that of
the electroless copper process, therefore, the water totals are adjusted to
take this into account. The BLACKHOLE™ adjusted total reflects 1A year
of processing, whereas the electroless copper total represents a full year.
TABLE 13. MAJOR OPERATING COSTS
Description
Chemicals
Tap Water
D.I. Water
Energy®
Labor
Waste Disposal
Waste Treatment
Totals
Adjusted
i
Electroless Copper
$89,600 :
3,200 \
503 ;
N/A
50,000
N/A ,
Labor 10.000
$153,000
Annual Cost®
BLACKHOLE™
$37,500
403
38.3
N/A
25,000
N/A
3.330
$66,300
Percent
Savings
58%
87%
92%
0%
50%
0%
67%
57%
The BLACKHOLE™ production rate is approximately twice as fast as that of the electroless copper
process, therefore the costs are adjusted to take this into account. The BLACKHOLE™ costs reflect
Vi year of processing, whereas the electroless copper costs represent a full year.
No significant difference is assumed in energy ot maintenance costs for the processes.
26
-------
TABLE 14* CAPITAL REQUIREMENTS
Input
Capital Cost
Capital Cost
Equipment
Materials
Installation
Plant Engineering
Contractor/Engineering
Permitting Costs
Contingency
Working Capital
Startup Costs
*
% Equity
% Debt
Interest Rate on Debt, %
Debt Repayment, years
Depreciation period
Income Tax Rate, %
Escalation Rates, %
Cost of Capital
$212,000
$0
$9,000
$500
$0
$0
$500
$1,500
$400
100%
0%
10.0%
0
7
25.0%
5.0%
15.0%
Output
Capital Requirement
Construction Year
Capital Expenditures
Equipment
Materials
Installation
Plant Engineering
Contractor/Engineering
Permitting Costs
Contingency
Startup Costs
Depreciable Capital
Working Capital
Subtotal
Interest on Debt
Total Capital Requirement :
Equity Investment
Debt Principal :
Interest on Debt
Total Financing
1
$212,000
$0
$9,000
$500
$0
$0
$500
$400
$222,400
$1,500
$223,?iOO
$0
$223,900
$223,900
$0
$0
$223,900
TABLE 15. DIFFERENCE IN OPERATING COSTS
Marketable By-Products
Total $/yr
Utilities
Electric
Total $/yr
Raw Materials
Chemicals
Water
Total
Decreased Waste Disposal
Reduced Waste, gal
OffsiteFees, %
Labor Cost, $
Transportation, $
Storage Drums, $
Total Disposal Costs, $
$0
$0
$0
$0
($52,100)
($3,260)
($55,360)
$0
$0
$6,670
$0
$0
$6,670
Operating Labor
Operator hrs (1,000)
Wage rate, $/hr $25.00
Operating Supplies $o
Total $/yr ; $0
Maintenance Costs (% of Capital Costs)
Labor ! 2.0%
Materials 1.0%
Supervision (% of O&M Labor) 10.0%
Overhead Costs (% of Operating
& Maintenance [O&M] Labor + Super.)
Plant Overhead 25.0%
Home Office • 0.0%
Labor Burden 28.0%
27
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TABLE 16. REVENUE AND COST FACTORS
Operating Year Number
Escalation Factor
1.000
1
1.050
2
1.103
3
1.158
4
1.216
Increased Revenues
Increased Production
Marketable By-Products
Annual Revenue
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Operating Savings (numbers in parentheses indicate net expense)
Raw Materials
Disposal Costs
Maintenance Labor
Maintenance Supplies
Operating Labor
Operating Supplies
Utilities
Supervision
Labor Burden
Plant Overhead
Home Office Overhead
Total Operating Savings
$58,128
$7,004
($4,641)
($2,321)
$26,250
i $0
i $0
$2,161
$6,656
$5,942
i $0
$99,179
$61,034
$7,354
($4,873)
($2,437)
$27,563
$0
$0
$2,269
$6,988
$6,240
$0
$104,138
$64,086
$7,721
($5,117)
($2,558)
$28,941
$0
$0
$2,382
$7,338
$6,552
$0
$109,345
$67,290
$8,107
($5,373)
($2,686)
$30,388
$0
$0
$2,502
$7,705
$6,879
$0
$114,812
TABLE 17. RETURN ON INVESTMENT
Construction Year 1
Operating Year
1 2 3
Book Value $222,400 $177,920 $142,336 $113,869
Depreciation (by straight-line) $22,240 $22,240 $22,240
Depreciation (by double DB) $44,480 $35,584 $28,467
Depreciation $44,480 $35,584 $28,467
Cash Flows
$0 $0 $0
Revenues $99,179 $104,138 $109,345
+ Operating Savings $99,179 $104,138 $109,345
Net Revenues $44,480 $35,584 $28,467
- Depreciation $54,699 $68,554 $80,878
Taxable Income $13,675 $17,138 $20,219
- Income Tax $41,024 $51,415 $60,658
Profit after Tax $44,480 $35,584 $28,467
+ Depreciation $85,504 $86,999 $89,125
After-Tax Cash Flow
Cash Flow for ROI ($223,900)
$85,504 $86,999 $89,125
Net Present Value ($223,900) ($149,549) ($83,764) ($25,163)
Return on Investment -61.81% -15.71% 8.15%
4
$91,095
$22,240
$22,774
$22,774
$0
$114,812
$114,812
$22,774
$92,038
$23,010
$69,029
$22,774
$91,802
$91,802
$27,325
20.84%
DB = declining balance.
28
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QUALITY ASSURANCE
A Quality Assurance Project Plan (QAPP) (Battelle, 1991) was prepared at the outset of the
project to outline testing, sampling, and analysis procedures. Testing and sampling were carried out
according to the QAPP with the following exceptions. The composite sampling time of the BLACKHOLE™
process line was reduced from the 150 minutes specified in the QAPP to 10 minutes. Due to the limited
processing times of the carbon black process employed at McCufdy Circuits, sampling tunes also were
limited. Because the system reaches steady-state quickly and there is little variability! in the continuous
process, a 10-minute sampling time was adequate. The data support this by the close agreement of the
copper readings between samples. The sample time of the electroless copper line also was reduced. The
QAPP estimated a sample time of 150 minutes to cover 5 line cycle times. Because the EC line processes
a rack every 17 minutes, the EC composite sample time was reduced to 90 minutes to cover 5 cycles.
Analysis of the samples was carried out according to the standard procedures outlined in the
QAPP. Duplicates and matrix spikes were analyzed as shown in Tables 18 and 19. The desired precision
TABLE 18. ACCURACY DATA FOR ANALYTICAL RESULTS
Parameter
Copper
Copper
Copper
Copper
Sample
No.
EC-2S
EC-IS
BH-B1
BH-B2
Regular
Sample
mg/1
0.375
0.212
0.060
0.014
Matrix-Spike
Level
mg/1
0.96
0.76
0.58
0.52
Matrix-Spike
Measured
mg/1
1.16
0.84
0.55
0.47
1 Accuracy
Percent
Recovery
81
83
85
: .87
TABLE 19. PRECISION DATA FOR ANALYTICAL RESULTS
Parameter
Copper
Total Solids
PH
Copper
Total Solids
PH
Sample
No.
BH-4S
BH-5I
BH-4S
EC-4I
EC-5C
EC-4I
Regular
Sample
mg/1
2.53
268
8.489
47.6
400
3.398
Duplicate
mg/1
2.51
276
8.489
47.3
408
3.398
Precision
Percent
0.8
2.9
0
0.6
2.0
0
Method Blank
<0.003
<40
_
<0.003
<40
_
29
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of 10% was achieved for duplicate analysis in this project. The QAPP called for an accuracy of 90 to
110% recovery for copper in the matrix spikes, which was not achieved. The results are still considered
valid at 80 to 90% recovery because they are being used as comparison values. The percent recovery
achieved was below 100%. Therefore, the project planners underestimated the waste reduction potential,
but not significantly. i
The QAPP detailed procedures for analyzing samples for formaldehyde. Table 20 shows
the results of the formaldehyde and, contrary to expectation, formaldehyde was present in the samples
from the BH process even though none of the BH formulations contain formaldehyde. The formaldehyde
could be from field contamination (no field blanks were taken for formaldehyde) or could be an interferant.
Compounds in publicly owned treatment works (POTW) samples are known to result in interference and
to give a false positive for formaldehyde (EPA Method^ 8315A). Thus, no conclusions can be drawn from
the formaldehyde analysis. The waste reduction assessment for formaldehyde is therefore based on the
chemical formulation information from the plant records.
TABLE 20. FORMALDEHYDE ANALYSIS RESULTS
Electroless Copper
BLACKHOLE™
Sample Identification
EC-2C
EC-1C
BH-3S
BH-6S
BH-10S
BH-10I
Laboratory Results
4.4
1.9
BDL
0.06
1.5
2.1
BDL: Below Detection Limit
30
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SECTIONS
REFERENCES
Battelle. 1991. Quality Assurance Project Plan for the BLACKHOLE™Technology Process Evaluation.
Prepared for the -U.S. Environmental Protection Agency Risk Reduction Engineering Laboratory,
Cincinnati, OH. '
Bracht,' W., and A. Piano. 1990. "Can Chemistry be Environmentally Attractive?" Printed Circuit
Fabrication, 13:(6).
Greeriberg, A. 1988. "BLACKHOLE™ — A Technology Update." Technical paper presented at IPC
Fall Meeting, October 24-28, Anaheim, CA.
Marien, B. A., and P. Pendleton. ND. "Plating-Through-Hole Colloid and Surface Phenomena,"
Technical paper presented at 5th Printed Circuit World Convention.
Metzger, W., J. Hupe, and W. Kronenberg. 1990. "New Process for Direct Through-Hole Plating of
Printed Circuit Boards." Plating and Surface Finishing, pp. 28-32 (February). \
Murray,!. 1989a. "BLACKHOLE™ Bandwagon Rolls." Circuits Manufacturing (December).
Murray,!. 1989b. "Chemistry In Small-Hole Plating." Circuits Manufacturing (September).
Nakahara, H. 1992. "Direct Metallization Technology, Part H." PC Fabrication, pp. 18-21 (November).
Polakovic, F. 1988. "BLACKHOLE™ — A Description and Evaluation." Technical paper, IPC Fall
Meeting, Anaheim, CA.
U.S. Environmental Protection Agency. 1992. Facility Pollution Prevention Guide. EPA/600/R-92/088.
Report prepared by Battelle, Columbus, Ohio.
31
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APPENDIX A
BLACKHOLE™ TECHNOLOGY INFORMATION
BLACKHOLE TECHNOLOGY:
the environmentally safer, proven alternative to electroless
MacDermid's innovative BLACKHOLE Technology can help
you improve the quality of the interconnects in your printed wiring.
board through-holes.
Quality Interconnects
BLACKHOLE Technology
provides for direct bonding between
the foil copper and the electrolytic
copper plating. Since both have
similar molecular structures, the
bond is especially strong. That means
fewer risks of defects caused by
separation and surface adhesion
problems.
Environmentally friendlier
Compared to the electroiess
ss, the BLACKHOLE
bath uses no formaldehyde, no
palladium, no stabilizers, and mini-
mal compiexors. That's safer for the
environment and your employees.
Less hazardous waste
BLACKHOLE Technology takes
an innovative approach to hazardous
waste by simply not producing a
significant amount in the first place.
In many cases the cost of waste treat-
ment and disposal can be cut up to
30% compared to electroiess copper.
Also, BLACKHOLE Technology
uses as much as 50% less water, so
there's less water less contaminants
to waste treat.
-------
PRODUCTION-PROVEN ELECTRO
a horizontally automated, fast and reliable through-hole plating process.
Conveyorized BLACKHOLE Technology increases your process control through automation. :
Now you get quality through-holes and increased through-put
See for yourself what the Conveyorized BLACKHOLE Technology has to offer. :
Conveyorized BLACKHOLE Technology consists of two horizontal conveyor systems working in tandem:
the flood /immersion unit where the BLACKHOLE chemistries are applied; and the Post-BLACKHOLE Unit which
removes the BLACKHOLE chemistries from all foil copper surfaces and preps the board for imaging. .
Fully automated
The BLACKHOL£ conveyor
system* features a remote-
control NEMA electrical
console, as well sis touch
control pads and computer-
ready electronics for smooth,
continual operation.
No racking, no dipping,
no dunking
Say good-bye to messy and
time consuming batch
processing. Since the system
is horizontally configured, it
significantly reduces materi-
als handling. And because it
is automated, the potential
for human error is reduced.
Easier process control
Conveyorized BLACKHOLE
Technology is based on non-
dynamic chemistry, resulting
in simplified process control
For example, the single
component BLACKHOLE
carbon black bath requires
monitoring only for pH and
solids content
Higher throughput
The BLACKHOLE Process E
conveyor system can produce
up to 120 completisd panels
per hour, based on 18" x 24"
boards with 2 inch, spacing,
and a conveyor speed of '
about 3.4 feet per minute. :
BLACKHOLE Flood/Immersion Unit
•The equipment illunnttd n minutacnirad by Advance tyiuiiu. Inc. Phacnuu Amam
33
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> -I
COPPER ALTERNATIVE:
Excellent integration with
contiguous processes
Conveyorized BLAGKHOLE
Technology integrates very
well with other horizontal
pre- and post-BLACKHQLE
processes. This contributes
to an exceptionally smooth
product flow from start to
finish.
Uniform application
Horizontal automation
provides consistent and
uniform application of the
BLACKHOLE chemistries to
all surfaces of the through-
hole. Automation also
assures mat every board is
exposed to the same process
conditions.
Reduced floorspace
The entire BLACKHOLE
conveyor system takes up
approximately 39 feet
(11.9 meters) of floorspace-
less titan the footprint of an
average electroless copper
setup. Conveyorized
BLACKHOLE Technology
frees, up a significant amount
of floor-space for more
productive uses.
Lower operating costs
Conveyorized BLACKHOLE
can save money in several
ways. Fewer chemicals, in
smaller amounts, means less
floor space devoted to
inventorying large quantities
of chemicals. Water usage is
drastically reduced. And
because you produce less
hazardous waste, less is
spent on waste treatment and
disposal
Post-BLACKHOLE/Pre-Imaging Unit
34
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