Recover particulate copper On debur operation, recover particulate copper using centrifuge or paper filter. Reuse water Reclaim etchant Send etchant to an off-site reclaimer instead of treating etchant in wastewater treatment system. Recycle photoresist stripper Decant spent photoresist stripper from polymer residue and recycle stripper. Do not discharge spent stripper to wastewater treatment system. V. Process Modification Eliminate chelated baths Change to a nonchelated plating bath to improve metal wastewater treatment.
Chelated streams make it difficult to precipitate metal in wastewater treatment system.
Segregate waste streams Increases recovery and treatment technology efficiencies. Acidic vs. alkaline. Chelated vs. nonchelated streams. Convert to dry floor Reduces chances of spills reaching floor drains or causing upset in wastewater pretreatment plant. An efficient etch machine results in less copper in rinsewater.