MAY 2018 I PCB007 MAGAZINE 81
Figure 19: The seven chemical/metals/water recovery systems and their ROIs.
Table 2: Annual savings from the elimination of chemical and water treatment
and recovery of valuable metals (copper and tin).
NOTE:
Resist strip
recovery enabled
by use of primary
image inkjet
process with hot
melt wax.
Whelen Engineering Chemical Recovery
Process Bath Recovery Method Recovered Product Capital ROI
Alkaline Etchants Oxidation/Galvanic Cu Fresh Etchant and Cu Metal 6-14 months
Acid Etchants Oxidation/Galvanic Cu Fresh Etchant and Cu Metal 6-14 months
Plating Electrolytes Organic Destruction Electrolyte minus Organic 2-3 months
Tin Strippers Galvanic Cell Etch Resist and Fresh stripper 4-6 months
Microetches Galvanic Cell Fresh Microetch and Cu Metal 4-6 months
Oxide Alternatives Organic Destruction Fresh Chemical minus Organic 2-3 months
Resist Strippers Membrane Fresh Stripper & Contaminated Brine 2-3 months
Whelen Engineering GREEN Savings
Process Step Liters/day of waste
Annual Cost of Chemicals &
Waste Treatment Savings
Pre-clean 120 $14,300
Pre-clean Rinse 3,600 $4,100
Developer 310 $12,100
Developer Rinse 3,600 $3,500
Etcher 1,440 $182,400
Etcher Rinse 3,600 $4,900
Stripper 240 $17,700
Stripper Rinse 3,600 $4,050
TOTAL
16,510 $243,050
CATEGORY SAVINGS
Annual Savings from Elimination of Chemical & Waste Treatment:
$243,050
Annual Savings from Reclaim of Copper for Resale:
$371,000
ANNUAL TOTAL: $614,050
References
1. Whelen Engineering and AWP Explain
their Unique Collaboration.
2. Process Control for HDI Fabrication.
3. Whelen Engineering Reduces Cycle Time
by Building a New Automated PCB Factory.
4. Whelen Engineering, Two Years Later.
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.
