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Counter-current rinse system

2007

Hi,
For acid copper & bright nickel(sulphate-chloride bath), after the drag out, I wanna employ a counter-rinse system.
I believe its water overflowing from the first rinse to the second,and so on. but don't quite know the details of it.could you help me out with the basics of it so that it can help me design the system.
Thanks

Rahul Kakkar
Plating shop owner - New Delhi, Delhi, India

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Hello Rahul,
Actually in a counter flow system the overflow travels from right to left, hence the word "counter". So in a 3 tank counterflow system its more like a 3-2-1 direction flow. The system ensures the last rinse is always the cleanest, and water rinse consumption is minimized. The tank can be divided into 3 sections or you could use 3 separate tanks. Tank or section #3 (far right) will contain your water inlet (preferably with a timer or sensing solenoid). The inlet pipe should go down to about 2" to the bottom of the tank to force any debris or drag-out chemicals to the top. The overflow dam and drain will be higher than the other two working to the left. The drain pipe is then angled down and plumbed to the next tank (to the left) at the bottom, with the same idea of forcing the debris or settled chemicals to the top. The overflow dam in the second tank should be 3" lower than the third tank. The same plumbing and overflow dam positioning would go for tank 2 to tank 1 except the overflow in tank 1 will be plumbed to your waste drain. There are other designs out there that work just as well as this one, you could check those out. Good luck to you.

Mark Baker
Process Engineer - Syracuse, New York
2007