What About the EPA?
The Lumiclad process utilizes zinc/molybdenum chemistry to form the black finish. In short, the Lumiprime step deposits a very thin layer of metallic zinc on the aluminum surface that serves as a primer for the Lumiclad molybdenum black oxide finish. Consequently, the rinse waters in the process line will contain very low concentrations of zinc and molybdenum. There are two options for handling these metal-bearing rinses:
- Small process lines usually do not exceed the regulated limit of 5 ppm.
Rinse tanks under 10 gallons can usually be discharged to the drain without treatment.
- Larger process lines use Ion Exchange to purify and recycle the rinse waters.
For process lines utilizing tanks of 40 gallons or more, Ion Exchange is a proven, cost-effective method for purifying rinse waters in a completely closed-loop manner, with no discharge of any kind to the sewer. No discharge permit would be needed. In this scenario, all the rinse water is collected and cycled through the Ion Exchange system that purifies it so it can be re-used in the rinse tanks. No water goes to the drain.