With Honeywell’s One Wireless technology all issues related to cabling within the paper machine were eliminated and every 30 seconds corrosion parameters (general corrosion rate, pitting factor, Stern-Geary parameter, Corrosion Mechanism Indicator) were downloaded into mill’s distributed control system (DCS).

As presented in Fig. 2, during the measurement period, several strong peaks of pitting factor were detected. Considering that pitting factor above 0.1 represents high system tendency for localized corrosion processes, it’s clear that during certain periods of time some process changes influence white water corrosivity. Online, real-time corrosion monitoring allowed linking the white water pH fluctuations with severe excursions in localized corrosion tendency. Due to proper neutralization procedure and maintenance of constant pH level, decreasing in overall tendency for localized corrosion could be achieved. Further examinations showed the key role of white water neutralizer in determining its potential for localized corrosion.

Using different neutralizers, Fig. 3, clearly shows the importance of a properly selected dosage rate and type of neutralizer. With a new neutralizer (marked as B), a strong decrease in pitting factor has been achieved. Moreover the base level of pitting factor fluctuations has also diminished.

By implementing Honeywell’s wireless corro-
sion monitoring solution, SCA was able to assess
and minimize corrosion in the white water stream at
Ortvikenl. Honeywell’s wireless corrosion transmit-
ters provided several benefits to SCA including:
•;Inside;view;on;processes;leading;to;pitting
corrosion and potential damages
•;Ability;to;monitor;several;different;corrosion
monitoring points with only a few transmitters
•;Wireless;system;offers;high;level;of;flexibility;in
reaching different corrosion monitoring points. PPI

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