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Corrosion problem in shell and tube chiller

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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

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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

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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 refrigration - Wuxi Jiangsu, China

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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 0.1 N Silver Nitrate in a 100 mL beaker 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 Editor's note:        Mr. Probert is the    author of Aluminum How-To / Aluminio El Como

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

Vanajambika Jeyakumar
- Chennai, Tamil Nadu, India