The Challenge
American Ammunition needed a plating system that could meet strict military specifications for copper-coated projectiles while minimizing environmental liability and operating costs. Like many metal finishers, they faced:
- Increasing regulatory scrutiny on metal-bearing wastewater discharge
- Rising costs for municipal water and sewerage
- Quality issues from contaminants in process chemistry
- Expensive pretreatment requirements for conventional rinse systems
The stakes: A conventional copper plating operation running three cascade rinse tanks would generate over 3,800 gallons of metal-bearing wastewater daily—all requiring pretreatment before discharge to the POTW.
The Solution
American Ammunition implemented a zero-discharge system built on three principles:
1. DI water throughout the operation
ResinTech supplied ion exchange resins (cation in hydrogen form, anion in hydroxide form) to remove calcium, magnesium, sodium, iron, sulfates, chlorides, alkalinity, and silica from city water—reducing TDS to approximately 5 ppm.
2. Closed-loop rinse design
Spray rinse systems capture 99%+ of process solution dragout and return it directly to source tanks, eliminating continuous discharge from rinse stations.
3. Minimal makeup water consumption
Daily DI water consumption: just 100 gallons for makeup and evaporative replacement.
The Results
Over six months of operation, American Ammunition processed 240,000 pounds of projectile material with remarkable efficiency:
- 0.007 gallons of wastewater per pound processed (1,600 gallons total over 6 months)
- Zero metals in discharge—only salts from resin regeneration and occasional process solution replacement
- 99%+ dragout recovery from spray rinse systems
- Extended process chemistry life due to virtually no contaminant carryover between tanks
- Simplified compliance—no metal-bearing wastewater discharge eliminates pretreatment requirements and reduces monitoring burden
Economic impact: Every gallon of water saved represents two gallons of cost savings—one from the municipal supplier and one from wastewater treatment. The closed-loop design dramatically reduced both.
Why It Worked
Low TDS is critical. Using DI water for all rinsing prevents dissolved solids buildup on parts and in tanks. Process chemistry stays cleaner longer, improving plating yields and consistency—essential for meeting military specifications.
Long DI system run times. Because water consumption was minimal (100 gpd), the ion exchange system ran longer between regenerations, reducing downtime and minimizing wastewater from the regeneration process itself.
Zero-discharge eliminates liability. No metal-bearing discharge means no pretreatment system, no complex compliance monitoring, and no risk of discharge violations.
The Takeaway
Zero-discharge plating systems aren't just environmentally sound—they're economically attractive. The combination of closed-loop rinse design and strategic use of DI water delivers:
- Dramatically lower water and sewer costs
- Extended process chemistry life
- Improved plating yields and consistency
- Simplified regulatory compliance
- Reduced long-term liability
For metal finishers facing tightening discharge limits or rising wastewater costs, American Ammunition's approach demonstrates what's possible when you design the system around water reuse instead of water discharge.
Want to explore zero-discharge solutions for your operation?
ResinTech works with metal finishers and plating operations to design DI systems that deliver the water quality you need while minimizing waste and regulatory burden. Contact us to discuss your specific application.
