Hazard Identification and Consequences Analysis of Possible Accidents in the Tank Farm & Flare of the ILAM Gas Refinery by ETBA and PHAST Soft wear

The ILAM Gas Refinery, which produces natural gas, ethane, C3+, C5+, and Sulphur, is situated in the west of Iran and in the Central Zagros Range, and thus, examining the consequences of possible industrial accidents considering the probable effects on personnel, equipment, installations, and the environment is of great importance.

In this study, the risks related to the storage tanks and flare were identified and prioritized. Then, the consequences of the identified risks for the selected scenarios comprising radiation due to fire, the pressure due to an explosion, and leakage of toxic material were modeled using the Process Hazard Analysis Software Tool (PHAST) for possible accidents.In this study, the ETBA method identified 70 risks, among which seven of them were in the unacceptable range, in which four risks were associated to the spherical storage tanks, loading (two risks), and the cylindrical storage tank and the flare were each assigned one risk. The risk associated with the heat energy of the spherical and cylindrical storage tanks and the flare were significant. Subsequently, the consequences of four scenarios including the sudden release of gas from the spherical storage tank, leakage of gas condensate from the cylindrical tanks, leakage of Liquid Petroleum Gas (LPG) from the loading arm, and flare-off were selected for simulation.

In the first scenario, the radiation resulting from fire and the shockwave of the spherical storage tank explosions affected a wide area of the refinery. In the second scenario, leakage of condensate gas from the adjacent wall to the cylindrical storage tanks is of certain significance. In the third scenario, the location of the loading platform is unsuitable. In the fourth scenario, the height of the flares is suitable and the release of toxic and flammable gases does not pose a significant consequence for the installations and people in connection. Reviewing the fire extinguisher systems, constant assessment of the lightning arrestors, and conducting firefighting drills are among the recommendations of this study.