MONITORING OF THE NEGATIVE INFLUENCE OF BIOFILM AND THE POSITIVE EFFECT OF CHLORINATION ON SURFACE PASSIVATION OF CUNI70/30 CONDENSER TUBES

摘要

The monitoring of corrosion behavior of CuNi 70/30 condenser tubes in sea water, performed in severalindustrial cooling systems, shows that the surface passivation of this alloy is strongly affected by thepresence of biologically active slime.The results obtained confirm the relevant role played by biofouling deposition against the formation ofprotective oxide layers on the exposed surfaces of the copper alloy to seawater and the positive influenceexercised by chlorination treatments based on short, intermittent and low level dosages.In the present paper, the innovative specific integrated equipment specifically set for industrial applicationand suitable to monitor electrochemically the corrosion (by Linear Polarization Resistance technique), thebiofilm growth (by the BIOX electrochemical probe), the chlorination treatment (by electrochemical andcolorimetric methods) and other physical-chemical parameters of the water is described in detail andcommented.