Performance Assessment of Cathodic Protection Systems for Buried Pipelines under Desert Conditions in Libya
DOI:
https://doi.org/10.37375/susj.v15i2.3716Keywords:
Cathodic Protection, ICCP, GACP, Pipeline Corrosion, CIPS, DCVG, Desert SoilsAbstract
Buried pipelines play a crucial role in transporting oil, gas, and water but are often exposed to external corrosion, particularly in dry, high-resistivity desert soils. Cathodic Protection (CP) applied either by sacrificial anodes (GACP) or by impressed current systems (ICCP) is widely adopted to control corrosion, yet its efficiency largely depends on coating condition, soil characteristics, and the uniformity of current flow.
This research investigates the performance of an ICCP system protecting a 10 km underground steel pipeline located in Sabha, southwestern Libya. Field evaluations were conducted during the driest season using Close-Interval Potential Survey (CIPS), Direct Current Voltage Gradient (DCVG) measurements, and anode current readings. Results indicated several under-protected sections with potentials between −0.76 and −0.82 V (Cu/CuSO₄, instant-OFF), corresponding to coating deterioration and restricted current spread. Statistical assessment revealed that soil resistivity, coating quality, and current imbalance jointly influence the level of protection achieved.
System optimization through rectifier recalibration, installation of additional sacrificial anodes, and combined CIPS–DCVG inspections improved the overall protection. The outcomes demonstrate that the conventional −0.85 V protection limit may not fully apply under arid conditions and suggest the adoption of adaptive hybrid CP systems supported by real-time monitoring to ensure long-term pipeline integrity.
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