MIC prevention in stainless
MIC prevention in stainless
(OP)
I have a cooling water loop that feeds a high temp furnace. 95% of the system is 316/304 SS including the furnace. What type of chemicals should I add to prevent MIC on the welds. The chlorides are about 2-7 ppm. Also, does Sodium Molybdate have any corrosion benifite for stainless cooling water systems?
Thanks
Thanks





RE: MIC prevention in stainless
I has been our experience that Molybdates aren't effective in preventing MIC on Austenitic SS.
Other than Chromates which will completely mitigate MIC, the only thing that has been effective is a low Chlorine dosage coupled with any other compatible treatment of the water being used. If MIC is established all bets are off.
This is based on our cooling water systems (5) used a giant pilot plants by the big three in the water treat business.
RE: MIC prevention in stainless
check. The bed will have to be replaced or recharged at some point. I suggest you analyze for chlorine/chlorides
before and after the carbon bed and replace when effluent levels begin to rise above acceptable values.
RE: MIC prevention in stainless
Do you have any idea about which bacteria are present in your water? Some species require different control methods.
RE: MIC prevention in stainless
Talk to the water treatment guys.
= = = = = = = = = = = = = = = = = = = =
Corrosion, every where, all the time.
Manage it or it will manage you.
http://www.trent-tube.com/contact/Tech_Assist.cfm
RE: MIC prevention in stainless
If biocides are used, it might be interesting to think about shock treatment. A shot of chlorine once a week has more effect than continuous dosage and is less expensive. However, do not use this in a system which already has a lot of biofouling, a lot of rubbish will detach from the metal surface and will enter your cooling system. There are interesting tools available to measure both active chlorine and biological activity on-line such as the Biotox of CESI. These can be used for process control when using bio-shock treatment.
Edwin Muller
KW2 Burau Veritas