78 PCB007 MAGAZINE I JANUARY 2019
an aqueous phase using sulfuric acid to form
copper sulfate (Figure 6c). The electrolyte
has the copper plated out as metal in the
electrowinning unit (Figures 6d and 6e).
The annual savings by eliminating chemical
and wastewater treatment for a facility of the
size of GreenSource is estimated to be over
$243,050 per year. The annual cost savings is
illustrated in Table 3 along with the savings
from the reclaiming of copper from etchants,
which is estimated to be $371,000 based on the
current cost of pure copper scrap. The copper
is so pure (99.99%) that it also can be used
in all the copper electroplating processes. No
solid copper is used as anodes.
Summary
The example of GreenSource Fabrication LLC
shows how Lean principles can go together
with green principles. Fifteen new innovations
in PCB manufacturing provide this advantage.
The results are a zero-effluent facility with no
need for recruiting direct labor, lower costs
(one-third to one-half the cost from China),
decreased lead times (from four weeks to two
days), prototype flexibility on high-volume
product lines, and improved quality with no
final inspection needed because humans do
not touch panels. This all occurs while utilizing
the maximum technology design rules.
PCB007
References
1. Matties, B., & Bernas, B. "Whelen Engineering Reduces
Cycle Time by Building a New Automated PCB Factory,"
The PCB Magazine, October 2015, pp. 12–39.
2. Stepinski, A. "The 21
st
Century PCB Factory—Designed
to Eliminate Offshore Cost Advantages," IPC APEX EXPO,
February 2016.
3. Stepinski, A. "Advanced PCB Fab Process Design,"
EIPC Conference, Scotland, June 2016.
4. Sigma Engineering AB. "Equipment for copper
recycling and modernization of PCB plant—product
brochure," June 2017.
Happy Holden has worked in printed
circuit technology since 1970 with
Hewlett-Packard, NanYa/Westwood,
Merix, Foxconn and Gentex. He is
currently a contributing technical
editor with I-Connect007. To read
past columns or to contact Holden, click here.
Table 3: Waste savings by not treating eight different types of PCB fabrication waste streams.
(Source: Alex Stepinski
[2]
)
