The Beauty of a Closed Loop
Client:
Decorative Chrome Plater
Problem:
Rinse water flow rate was not able to keep up with demand. Final rinse was too contaminated for the parts to be considered rinsed and clean. The first rinse tank was a stagnant “Drag Out” tank and not a live rinse. The Drag out tank became more concentrated than the Chrome tank. Not only was the final rinse ratio unacceptable, the customer was spending a considerable amount of money on chrome adds to keep the process tank concentration at the appropriate level to counteract the dilution from drag out into the rinse tanks. In addition, they had to introduce a large amount of fresh water to the rinse tanks.
There were considerable costs that were working against the client. Not only is it expensive to purchase chrome but it is also costly to treat it. In this instance, they were generating hexavalent chrome and therefore, had to convert it to trivalent chrome before they could begin to utilize traditional waste treatment methods for metals precipitation.
Process:
The customer was using a “dead rinse” as well as two additional rinse tanks. We needed to find a way to extend the life of the rinse tanks and to reduce the amount of chrome being introduced to the system.
Solution:
We chose to eliminate the “dead rinse” and convert it to a live counter-flowing rinse, implement a three counter-flow rinse tank system. In addition, we installed an evaporator and a Companion Condenser™ on the chrome tank.
This closed loop system provided a significant cost savings on the purchase of chrome and eliminated the cost of waste treatment of the chrome. They no longer needed to treat for chrome because it was being recovered from the rinse tanks and reused. The Companion Condenser™ recovered the evaporated water and returned it to the final rinse as clear, clean distilled water. The ET-III-W™ evaporated 15-20 GPH from the chrome tank while returning a matching 15-20 GPH of distilled water back to the last rinse tank to start the counter flow. The Companion Condenser™ helped to drastically reduce the amount of fresh water that needed to be introduced to the system by sending the recovered clean water back to the final rinse tank. So, not only did the company save money on the purchase of expensive chrome, they reduced their waste treatment and fresh water costs while dramatically improving quality and rinse ratios simply by adding an inexpensive Poly Products evaporation system.