Thursday, March 20, 2008 - 11:35 AM
Convention Center, First Level, La Louisiane B/C (Ernest N. Morial Convention Center)
08139

In-Plant Piping Hydrogen Induced Cracking Survey at a Gas Oil Separation Plant (Case study)

Mohammed F. Barout, Mohammed Al-Anezi, Hashim S. Al-Awami, and Mohammed A. Abufour, Saudi Aramco

A detailed survey of hydrogen induced cracking (HIC) was made at a Saudi Aramco Gas Oil Separation Plant (GOSP). A hundred and seventy identified HIC pipe spools were covered in this intensive field survey. The survey that commenced more than 18 years ago was used to monitor critical equipment and piping.

 The HIC survey program is conducted on an annual basis at the GOSP facilities using ultrasonic on-stream inspection (OSI).  The objective of this survey is to inspect, monitor and identified severely effected plant piping/equipment to avoid occurrence of any catastrophic failure.  Indications of HIC, categorized as moderate to severe with continuous loss of back wall refection, have been recorded on many equipment and piping spools, particularly in the 30” gas outlet line of High Pressure Production Trap (HPPT) and the 24” crude inlet and outlet Desalter lines.  This particular GOSP was built in 1982. It produces 300 MBOD of crude; when separation takes place a total of 100 MMSCFD of sour gas is gained. 

 Additional advance ultrasonic examination (P-scan and high temperature mapping) was conducted just recently on selected locations to provide more detailed information for a risk based assessment review. The next major plant T&I is due in 2009.  Pipe replacement will be deferred for two years; and significant cost savings through production loss avoidance will be realized. As such, potential short term repair measures, including full metallic sleeves and non-metallic composite wrapping, to extend the service life of the affected piping until the next scheduled T&I, are being considered.