Online corrosion monitoring through Linear Polarisation Resistance (LPR) Probe

Water treatment professionals and companies rely on predictive and diagnostic tools to evaluate the incidence or inhibition of corrosion in water systems. While predictive tools like saturation indices are most often employed, their usefulness is limited against measured corrosion rates.

Linear Polarization Resistance (LPR) is an electrochemical method of measuring corrosion that allows monitoring of corrosion rates in real-time, making it useful in identifying upsets and initiating remedial measures.

PCC employs LPR probes and data loggers to allow monitoring of corrosion rates for clients as a diagnostic tool. As part of a full-scale study, a Cosasco LPR probe was deployed at a cooling water system in Lahore. The chemical-free cooling water treatment program intentionally targeted maintaining a slightly positive LSI through blowdown control and main- training low cycles of concentration. During the diagnostic evaluation period, the cooling water system was operated at low cycles of concentration, maintaining a TDS concentration in the cooling tower to around 800 mg/L, and an LSI around +0.5. The resulting corrosion rates were found to be well in excess of 5.0 mpy  and as high as 13.5 mpy and classified as poor to unacceptable.

The results were corroborated through long-terms corrosion coupon exposures, and results from the weight-loss tests supported corrosion rates from LPR measurements.

Industry: Food & Beverage

Application:

• Cooling Water
• Online Corrosion Monitoring

Location: Lahore

View of corrosion coupon rack along with provision for analytical (conductivity and pH) and diagnostic (LPR) probes. Probes can be connected to a remote HMI for access through cell phones and PCs for permanent installations, and dataloggers for diagnostics only.

How are your chemical treatment programs for corrosion inhibition performing?

Contact Prime Chemicals Corporation to book a diagnostic evaluation session: