Modifications to Reduce Drag Out at a Printed Circuit Board Manufacturer

摘要

The MnTAP/EPA Waste Reduction Innovative Technology Evaluation project at Micom,Inc., demonstrated the waste reducing capability of two simple rinsing modifications on an etchant and an electroless copper process. The simple, low (or no) cost, low technology changes that were made were: (1) slowing the withdrawal rate of the racks containing the printed circuit boards as they are pulled from concentrated process tanks and (2) combining an intermediate withdrawal rate with a longer drain time over the process tanks before transfer to the rinse tanks. As compared to baseline sampling, both modifications reduced drag out by 41 to 52% of concentrated copper containing bath solutions into the rinse water systems that followed the bath tanks. Economic savings in avoided treatment and disposal costs of $3120 to $3350 per year were also shown.