47001

How to remove the chlorine ions on stainless steels surface  

+++++++

Our company makes petrochemical process equipment in Korea.
Now, we have several pieces of stainless steel equipment like 304, 304L & 316L.
Our client requests us to use de-mineralized water that the chlorine content is under 2 ppm during a pressure test to prevent any corrosion due to chlorine ions.
However, we don't have any facility to make the de-mineralized water; and, the water volume is very big.

Is there any way to remove the chlorine ions on the stainless steel face after the pressure test with general water?

S.M. Jung
- Changwon, Kyeongnam, Korea

I think you are asking the wrong question, S.M. The right question would be something like "how can I economically provide the required water of 2 ppm chlorine?" :-)

I don't know whether the chlorine exposure can cause permanent damage to the stainless steel, but I don't think we can rule that out.

Ted Mooney, P.E.  finishing.com Brick, New Jersey

I would look into getting a reasonable sized reverse osmosis unit. A good pre filter, then a granulated carbon filter followed by a lower micron filter than your first filter will remove a large amount of chlorine, but NOT chloride. Recycle your water thru the RO unit into a storage tank that is plastic.

James Watts
- Navarre, Florida

Usually 2 ppm of chlorine does not cause enough of a problem to worry about. If it is chlorIDE, it is more of a problem.

Ted is correct, in that it is not too hard to make water that is less than 2ppm of chlorine. What quantity are you talking about? There are not too many chlorides that are insoluble in that low a concentration, so you probably need to go to a RO or DI process. You could rent a DI system probably.

Lee Kremer Stellar Solutions, Inc. McHenry, Illinois