Corrosion Prediction in Process Piping Using Handheld X-Ray Fluorescence (XRF)

Positive Material Identification (PMI) has become an important inspection protocol at petroleum refineries and power plants around the world to help prevent catastrophic failures of piping systems. Many of these failures are caused by accelerated corrosion resulting from the chemical makeup of the pipes. Three corrosion mechanisms will be discussed which include Residual Elements in HF Alkylation Units, Sulfidation, and Flow Accelerated Corrosion (FAC).

Traditionally, chemical analysis of carbon steel piping has been performed by laboratory analysis of filings, or more recently, by use of spark-based optical emission spectroscopy (OES) instrumentation. With its dramatically improved detection limits, ease of transport, reduced sample preparation, and nondestructive analysis, handheld x-ray fluorescence technology has now become a valid and industry-accepted method for PMI. Details of recent advancements of handheld XRF technology will be provided in the paper, and how it can be used as a tool to prevent failures due to accelerated corrosion.