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Louisiana Refinery Accident Database

Marathon Ashland Petroleum (3165), Garyville

LDEQ Accident Report

Pollutants Released

Accident Classified As: Reportable Quantity

Cause of Problem: Process Upset

Chain of Events: While placing amine filters in service, an upset occurred in the Unit 247 Amine Regeneration Unit Overhead Receiver. A high liquid level in the Receiver caused liquid to be sent to the Sulfur Plants. The Unit 220 and 234 Sulfur Plants shut down due to high knockout drum levels. This caused an elevated flow to the remaining operational sulfur plants. The Unit 34 Sulfur Plant then shutdown due to low boiler feed water level in the Reaction Furnace. Unit 247's lean amine became saturated as a result of the high acid gas header pressure, resulting in less than adequate hydrogen sulfide absorption in RFG producing units, causing both Refinery Fuel Gas Mix Drums to experience high levels of hydrogen sulfide. This fuel gas was then combusted in all the refinery's heaters that were operating on refinery fuel gas. Summary: An upset in the Unit 247 Amine Regeneration Unit caused an opacity exceedance and sulfur dioxide reportable quantity exceedance in the Sulfur Plants and at all the process heaters, which combust refinery fuel gas. MPC originally reported that the upset began in the Coker Unit, but, after further investigation, stated that the Coker Unit was not involved in the incident.

Discharge Preventable - Under Investigation

The results of the Root Cause Analysis will determine whether or not this incident was preventable.

Notes/Remedial Actions

Process unit charge rates were reduced in accordance with the refinery's sulfur shedding plan. Sulfur plants were re-started as soon as possible in order to convert more hydrogen sulfide to sulfur. The refinery dispatched 3 Air Monitoring Teams, and no pollutants were detected at the fenceline. The Air Monitoring Team data is attached to the report. Mobile SO2 meter was post calibration expiration. (AreaRAE #240) Corrective actions given in follow-up report: Review and reinforce procedure use with 552 Board Operator, Issues Lessons Learned to emphasize the requirement and importance of using procedures, Review and reinforce procedure use with 532 Operator, Investigate a means to maintain LP BFW header supply while spare LP BFW is out-of-service, Investigate upgrading U220/U234 Amine Acid Gas KO Drum Pumps from 25 gpm max to 50 gpm max, Train 001 shift supervisors on the updated refinery sulfur shedding procedure and importance of following the procedure to emliminate a large sulfur dioxide emissions incident, Update Unite 232/247 Carbon After Filter Change-out Procedure to utilize FC0051 to help ensure that a surge of flow cannot be routed to Regenerator during the filter start-up, Update DCS graphics to clean-up the FC0051 split-range control and PC0021 selector control schematic to help improve operator understanding, Provide face-to-face training on the updated procedure and schematics for each Board Operator, and Update refinery sulfur shedding procedure such that unit charge rates are reduced quickly enough to minimize sulfur dioxide emissions during sulfur unit shutdowns.