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Corrosion problem in shell and tube chiller

DEAR SIR/LADY

WE ARE USING SHELL&TUBE CHILLER MADE OF ST.ST SHELL AND CU/NI 90/10 TUBES THE COOLANT IS INHIBITED 40/60 ETHYLEN GLYCOL/DEIONIZED WATER. THE COOLANT FLOWS TROUGH ST.ST PIPES TO ALUMINUM FINNED COLD PLATES AND RECIRCULATE TO THE CHILLER.

THE QUESTION IS:

IS ANY CORROSION PROBLEM IS EXPECTED DUE TO TORBULANT FLOW TROUGH THE CHILLER. IF YES, COULD YOU FORESEE, AFTER WHAT PERIOD?

THANK YOU IN ADVANCE

Jacob Mor
- Ashdod, Israel
2004

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Dear Jacob:

I don't think you will face any problem at all to Cu-Ni, SS or Aluminum.

I have used Cu-Ni tubes in Ethylene Glycol (MEG)/water evaporators for years without problem. Cars' aluminum engine blocks service life is a testimony to the efficacy of corrosion inhibitors.

If you want more info consult US Patents (4085063, 3948792, 3340001, 2560839) for antifreeze inhibitors.

Vinh Le
- LaCrosse, Wisconsin
2004

If my coolant is water of including 300PPM Cl, My condenser of chiller system will use the tube of Cu. Will it have any corrosion problem

Hongming Hu
air conditioning and refrigeration - Wuxi Jiangsu, China
2004

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Just be sure that the last time you back washed the D.I.resin beds that absolutely NO Chloride was left behind and/or is coming through the system. Also look for galvanic corrosion. Test for chloride by 1 drop of 0.1N Silver Nitrate in a 100 mL beaker [beakers on eBay or Amazon] of the circulation water. If it clouds there are 50 ppm chlorides present which will eat up the stainless steel.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

2004

Impressed Current Cathodic Protection (ICCP) by using DSA titanium anodes will solve the corrosion problem.

Vanajambika Jeyakumar
- Chennai, Tamil Nadu, India
2004