FGP Sulfur Recovery Units have 18 sulfur collection pumps, 3 pumps each train, equipped with mechanical seal plan 74. This plan receives the supplier barrier gas (Nitrogen) from utility plant. During the normal walkthrough after T&I’s completion, it was observed that total of six (6) pumps experienced low seal pressure. A thorough analysis was conducted and the investigation concluded that ingress of sulfur fume from process side caused sulfur solidification between seal faces and impacted the seal performance. The cause of fumes appearance in the seal is the isolation of the supplied nitrogen which was part of T&I procedure.
FGP succeeded and managed to restore the performance of all impacted mechanical seals by introducing a heat blanket solution which impacted positively to melt the solidified sulfur between seal faces. FGP capitalized on the internal resources in which resulted to resolve the mechanical seal issue safely and timely instead of mechanical seal replacement. In addition, special procedures were developed to ensure the continuity of nitrogen supply to mechanical seal in order to eliminate the risk of sulfur fumes exposure.