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Keeping metals out of landfills

- by Matt Stevenson

Reflecting upon our most recent Earth Day (April 22) and hearing of our planet healing itself during the global shutdown of industries related to the Covid-19 outbreak, I am reminded that there are so many opportunities in the PCB manufacturing to do our part to keep waste from the landfills.

There are many potential waste streams in the PCB manufacturing process that are recyclable and Sunstone does its’ part to ensure that as many of these as possible are properly recycled.  Metals (gold, nickel, copper, lead, silver, and tin) from scrap PCBs, overbuild PCBs and the manufacturing panel frames, waste treatment, and in-process reclamation are probably the largest source of opportunity for recycling.  Sunstone typically recycles approximately 30,000 pounds of these metals every year preventing them from entering landfills and allowing them to be reused in other applications.     

In addition to these metals, there are plenty of other ways that we are able to remain environmentally conscience, several of the chemicals used in the manufacturing process can be used by other applications as starter chemicals.  We can repurpose our spent etchant when the copper in solution gets too high to be used effectively in the process.  It can be sent back to the manufacturer and used as a starter for other chemistries or recycling the copper.  Precious metals like gold and silver are collected from rinses directly following plating baths to prevent these from being flushed into the waste treatment system. Being conscious of our internal water streams and usage, being able to keep as many closed-loop systems, cascading rinses, monitoring the ionic cleanliness of rinses within processes all contribute to less water usage and less negative impact to the environment.

Making PCBs can use a lot of natural resources but being mindful to recycle, reduce, and reuse as many of these as possible allows us the opportunity to be a good steward to the planet.  Not all manufacturers have this same level of interest in sustaining our environment, especially in countries where it is unregulated.  You should know where your suppliers are in terms of maintaining this very fragile planet of ours.