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80 PCB007 MAGAZINE I MAY 2018 takes just 205 minutes to finish the boards to final fabrication and solder mask. Even though three final finishes can be randomly selected (OSP, LF-HAL, or ENIG) and laminates with different copper weights are used, the process runs continuously unless interrupted to im- age and etch innerlayers, and it can be accom- plished for a wide variety of products because of the unique, horizontal pulse-plating panel plate with inkjet image printing of resist and pattern plating of tin as the etch resist. As innovative and ground-breaking as all the automation is at Whelen, what is truly remark- able is the green/no effluents status of their manufacturing. The central water recycling system is shown in Figure 18. There are six main concepts that make up the zero-effluent strategy at Whelen. 1. Hermetically seal all process equipment to recover the water and chemicals from fumes. 2. Increase the temperature of all processes to evaporate as much water as the process will tolerate (collected by the hermetic seal system). 3. Make the first water rinse after the heated process a contamination capture and replenishment make-up for the preceding process (under continuous automatic chemical monitoring). 4. Make the successive water rinses a 'high-flow-rate" for effective rinsing. 5. 100% recycle this water utilizing ion- exchange and dual reverse-osmosis. 6. Isolate certain process streams and recover valuable chemicals or metals. These chemical/water recovery units (Figure 19) are: • Unit 1: Regenerate etchant/recover Cu+ and recycle etchant • Unit 2: Plating electrolytes destroyed • Unit 3: Tin stripper—recover tin and recycle • Unit 4: Oxide alternative—organic destruction • Unit 5: Acid etchants • Unit 6: Microetches • Unit 7: Resist strippers In their efforts to recover all their water and conserve their impor- tant chemicals/metals, the green theme of Whelen has led to a rapid payback and ROI recovery. Table 2 shows the annual savings from these systems. Over $614,050 is saved annual - ly. The wastewater system was automated to the point of requiring only 10 hours/ week of total labor. Total capital expenditure for all chemical recovery systems associated with this project was $1.4 million. The many innovations at Whelen are best under- stood by reading the two articles published in I-Con- nect007's The PCB Mag- azine on October 2015 [3] and August 2017 [4] . PCB007 Figure 18: Schematic of water recycling system. Inline Process Inline Static rinse Inline Cascade rinse Collect Wastewater Remove Contamination (Core Wastewater Recovery System) Water Returned to Process or Discharged Weak Acid/ Strong Base Ion Exchange + 2 Pass RO Hermetically sealed system with output recycled OUTPUT 1: Waste brine trucked off. OUTPUT 2: Metals removed and reduced to solid with decontaminated brine either trucked off or discharged. Distilled water returned to process Extra brine reprocessed Waste Brine FILTER PRESS Thermal Distillation Sludge Dewatering Final dewatering by air flow (Product is 65%-80% solids) UNIT 1: Regenerate etchant /Recover Cu+ recycle etchant UNIT 2: Plating electrolytes destroyed UNIT 3: Tin stripper-recover tin and recycle UNIT 4: Oxide alt.-organic destruction Recovered Cu & Tin for sale Process Sealed Tank Centrifugal Pump Vertical Pump Centrifugal Pump Whelen Zero Effluent Typically non-hazardous solid for disposal