Effect of Elemental Sulfur Deposits in Refinery Heat Exchangers - A Case Study

Introduction

Heat exchangers are process equipment in which heat is continuously transferred between hot and cold fluids, or vice versa, directly or indirectly through a heat transfer surface that separates the two fluids. Heat exchangers consist primarily of bundles of pipes, tubes, or plate coils. Elemental sulfur corrosion in oil and gas production systems, refinery heat exchanger tubes, and fin-fan coolers is an insidious form of attack that initiates pitting corrosion by creating small anodic with large cathodic areas where the passive/protective film formed on the metal surface is often broken.^1,2,3,4,5 The resulting fouling reduces the heat transfer efficiency of the heat exchangers.⁶ There are multiple initiators that can cause under deposit corrosion (UDC) in process equipment in addition to sulfur, which is the focus of this article.⁷