Analysis Oxygen Piping Layout to Eliminate High Consequences Risk

Abstract

During detail engineering project for EG3 (Ethylene Glycol Plant no.3) for Jubail United Petrochemical Company, a SABIC affiliate, the writer found oxygen feed header from Gas Plant pipeline laydown on pipe rack instead of underground as standard practice for existing plants. Currently, as the oxygen pipe passes the hydrocarbon product storage tanks, there are hydrocarbon products pipelines above it with only a 4-meter space in between. Oxygen is an oxidizer, and in oxygen-enriched atmospheres, the reactivity of oxygen significantly increases the risk of ignition and fire. Materials that may not burn in normal air may burn vigorously in an oxygen-rich environment. Materials that burn in normal air may burn with a much hotter flame and propagate at a much greater speed. The onset of this enhancement is seen at 25% oxygen level in the atmosphere and reaches its maximum from approximately 40% oxygen concentration as per section 6.2 Oxygen Enrichment or Deficiency of Determination of Safety Distance (IGC Doc 75/07/E) published by European Industrial Gases Association AISBL. This paper delves into three approaches which are: oxygen's effect on the surrounding area, the surrounding area's (specifically fire's) effect on the oxygen line, and a comparison to the standard. Based on the three dimension risk analysis made, the writer concludes that the current configuration is unsafe and potential to high risk. Although the cost of construction increases significantly, rerouting the oxygen pipe is the best option because safety is more valuable.