LA Bucket Brigade : Refinery Accident Database

About the Database

Motiva Enterprises (2719), Convent

Releases in 2011

LDEQ Accident Number Accident Date	Point Source/Release	Cause	Notes
135985 2011-12-19	Point Source(s): flare #2 Pollutant(s): Sulfur Dioxide - 346 pounds	Cause of Problem: Instrument Failure The incident occurred at Motiva's Refinery on 12/19/11 due to an upset of the refinery's fluid catalytic cracking unit (FCCU). The upset began when the FCCU Wet Gas Compressor controller unexpectedly switched to back up and slowed the FCCU Wet Gas Compressor speed down. This over-pressured FCCU Fractionator tower which caused the tower's pressure controller to open the flare. The FCCU Wet Gas Compressor controller was taken out of automatic mode and placed into manual mode and the speed was increased to reduce the FCCU Fractionator tower pressure. The flaring ceased when the pressure reduced on the FCCU Fractionator.	No Information Given. Claims that they released 346lbs OVER the permitted limit but did not exceed 500 lbs. The value is greater than 346 lbs and less than 500 lbs.
134255 2011-09-29	Point Source(s): No Information Given Pollutant(s): Oil - BRQ	Cause of Problem: Piping or Tubing A pinhole leak in line resulted in an oil release.	No information given for remedial action. Motiva states that mostly water was leaked and a RQ exceedence was not reached. LDEQ only no Refinery Letter included.
133665 2011-09-08	Point Source(s): Refinery Flare No.1, No.2 and No.3 Pollutant(s): Sulfur Dioxide - 1,952 pounds Hydrogen Sulfide - 4 pounds	Cause of Problem: Equipment Failure Motiva states that initially the upset began after routine maintenance on a Wet Gas Compressor flow transmitter. The Suspected Controller sent a signal to open the anti-surge spill-back creating a recycle from the compressor discharge to suction. A compressor malfunctioned causing flaring in Refinery Flare No.1, Flare No.2 and Flare No.3 cumulatively beyond permit limit and the release of 2,097 pounds of SO2.	LDEQ and Follow-Up provided, but there was no Refinery Letter included. Motiva states that there was a non-preventable release of approximately 1,952 pounds of SO2 and 3.68 pounds of H2S. The Catalytic cracking controllers (CCC) were replaced and the data recording software was upgraded and is being analyzed.
133797 2011-09-03	Point Source(s): Terminal Drain Pollutant(s): Hydrocarbon - 210 gallons	Cause of Problem: No Information Given Motiva Truck Terminal drained backed up outside of the fence and overflowed Hydrocarbon gas, [Liquefied] "oil" into the refinery. No information given about what caused drain to overflow and release oil.	Motiva states that "Boom was deployed and the Hydrocarbon gas, [Liquified] "oil" remained on the refinery site until it was vacuumed out". No injuries were reported and no offsite impact occurred according to Motiva. No refinery letter included.
132607 2011-07-19	Point Source(s): s11-2327 mobile container Pollutant(s): Sodium Hydroxide - 3,445 pounds	Cause of Problem: Equipment Design An employee was unloading a 330-gallon plastic tote of 50% caustic solution from a truck when the contents shifted and the tote turned on it's side.	Spill occurred in a controlled area, spill was remediated. No offsite impact. Vacuum truck dispatched to release location to remove pooled liquids that had accumulated on ground surface. Small excavator used to scrape any remaining stained soil. Soil will be tested for caustic traces.
132250 2011-07-06	Point Source(s): VPS-1 Crude transfer line Pollutant(s): Crude Oil - 84 gallons	Cause of Problem: Corrosion Motiva operations discovered oil on the ground beneath a pipe rack located near Avenue C in the west section of the tank farm between tanks 20D-31 and 20D-46. The source was determined to be a leaking 10 inch VPS-1 Crude transfer line. The spilled material remained within the boundary of the rank die area, therefore there were no offsite impacts as a result of the incident.	A Motiva operator isolated the leaking section of the pipe. The spilled material remained within the boundary of the tank dike area. The free liquid was routed from the tank dike to the dirty oil sewer where it is directed to API. An on-site contractor that specializes in spill clean-up responded and the recovered contaminated soil was placed in roll-off boxes for proper disposal. The remediation process was completed with the addition of Nitrogen-enriched Micro Sorb to the ground to further promote biodegradation of any low level residual hydrocarbons. The leaking section of the line remains out of service and will be permanently removed. The remaining portion of the crude transfer line will be inspected by the pressure integrity department to identify any other areas of concern. Oil cleaned up through a vacuum truck and absorbent pads.
130690 2011-04-21	Point Source(s): Sulfur Unit (SRU-4); TGTU No 4 Pollutant(s): Sulfur Dioxide - 1,467 pounds	Cause of Problem: Process Upset State police report states that an unplanned shutdown occurred due to an upset in the sulfur unit, causing a release in sulfur dioxide. The incident originated with the unit re-start of the Fluid Catalytic Cracking Unit (FCCU) which then affected the processes of the Amine Recovery Unit (ARU).	Operations modified the start-up procedure to better diagnose a buildup of backpressure from downstream.
130716 2011-04-15	Point Source(s): Steam Boiler Pollutant(s): None - 0	Cause of Problem: No Information Given LDEQ states that steam boiler was shut down due to excessive noise.	Steam boiler was shut down. LDEQ included. No Refinery Letter.
130936 2011-04-15	Point Source(s): TGTU-4 Incinerator FCCU WGS Pollutant(s): Sulfur Dioxide - 500 pounds Carbon Monoxide - 0	Cause of Problem: Process Upset The incident began at Motiva's Convent Refinery on 4/15/11 when the refinery's Boiler # 4 shutdown due to an internal tube failure. With the loss of the boiler, the refinery transitioned to steam curtailment and several units were forced to reduce charge rates. As units were being reduced, the excess fuel gas not being utilized was routed to the refinery flare gas system (flares #1 and #2). The opacity limit was exceeded due to the lack of steam available in the refinery to affectively control the smoke while flaring the excess fuel gas. Also during the transition, the FCCU experienced an upset which caused hydrocarbon to under carry from under the high pressure fuel gas knock out drum into the amine acid gas header. The amine acid gas header feeds the Tail Gas Treating Units in the Sulfur Recovery Plant. As the amine acid gas (and the entrained hydrocarbon carried under from the FCCU) was combused in the TGTU-4 Incinerator, the sulfur dioxide and opacity released through the stack was above permitted limits. The excess emissions ceased when the FCCU was stabilized.	Report notes that Motiva exceeded their emission standards for opacity limit and the maximum limits of sulfur dioxide and carbon monoxide in lbs/hr. Motiva states that they exceed the 500 pound reportable quantity for sulfur dioxide.This report does not say the duration of the release or the amount of pollutants that were released. Report was found during a written notification process.
130553 2011-04-11	Point Source(s): flare #2 Pollutant(s): Sulfur Dioxide - 3,586 pounds Hydrogen Sulfide - 7 pounds	Cause of Problem: Instrument Failure Incident occurred due to an upset of the refinery's fluid catalytic cracking unit (FCCU). The FCCU Wet Gas Compressor has three speed probes wired to the Triconex system, which performs the governor controls for the compressor's desired speed. The Triconex system processes the three speed readings and sends an electronic output signal (basically an average speed value of the three probe readings) to the CCC control system (which includes a 1st and 2nd stage antisurge controller). The CCC controller uses the speed signal to determine if the the compressor is "running" of "stopped". The upset began when the 1st Stage Wet Gas Compressor speed signal malfunctions sending a false reading to the compressor speed controller to decrease speed. The speed controller interpreted the low speed signal to mean the compressor was shutting down. To protect he compressor it fully opened the anti surge spillback creating a recycle from the compressor discharge to the suction. Since the low speed signal was false and the machine was not shutting down the recycle overloaded and the capacity of the Wet Gas Compressor and it could not keep up with the gas coming from the Main Fractionator. With the Wet Gas Compressor maxed out, the gas from the Main Fractionator Overhead could not get out and the pressure controller opened to the flare. The flaring ceased when the spillback valve was closed and the pressure reduced on the Main Fractionator. The flaring was a result of over pressuring of the Fractionator. The over pressure condition occurred due to the Wet Gas Compressor antisurge recycle valve going fully open due to a false low speed reading reading on the 1st stage anti surge controller.	Operations took immediate action to begin the process of stabilizing the FCCU by cutting back unit charge rate. Both the 1st and 2nd Stage Wet Gas Compressor speed controllers were set to from automatic to manual while E&I began troubleshooting the speed signals. Actions were taken to provide the operator an alarm in the event the condition reoccurs with instructions on how to mitigate until technical support arrives. All wiring associated with the CCC Control system was inspected on 4/11/11. Voltage checks were performed on all circuits and the speed signal was tested on 4/11/11. The CCC controllers will be replaced and the data recording software will be upgraded during the 2011 FCCU turnaround for a target completion date of 8/31/11. Flare # 4 exceeded maximum opacity limits during this incident.
130425 2011-04-05	Point Source(s): VENT: Flare #1 tip Pollutant(s): Hydrogen Sulfide - 1,280 pounds	Cause of Problem: Seal or Gasket The apparent exceedance was discovered at approximately 9:20 am while Motiva Convent Refinery was preparing to perform maintenance on the Refinery Flare #1. A valve, upstream of the flare knock out drum, was used to isolate the flare line from the process to remove any residual hydrocarbons from the system prior to work being performed. However, the valve apparently leaked by allowing process gas to enter the flare knock drum and subsequently released gas through the flare tip. Since the flare was out of service at the time, there was no flame present to combust the process gas before exiting the flare tip. None of the potential exceedances listed have caused an emergency condition. There was no offsite impact as a result of this incident. Exceeded RQ 100lb H2S and 3.3lb/hr H2S	A water seal was re established in the flare knock down drum which created a barrier to prevent gas from entering the vessel and subsequently existing the flare tip. the barrier created by the water level in the knock out drum was monitored and controlled using level instrumentation. The water level controller was set to "Auto" to ensure drum water level (ie water barrier) is maintained. Operations vegan visual monitoring for water level at the flare drum to ensure the barrier stayed intact.
130985 2011-04-03	Point Source(s): Sulfur Recovery Unit Pollutant(s): Sulfur Dioxide - BRQ	Cause of Problem: No Information Given No Information Given.	This report is a written follow up to the courtesy call made on 4/3/11 concerning the release of sulfur dioxide on Convent's Sulfur Recovery Unit. The incident was initially reported to the LA State Police as a potential RQ exceedance based on limited information available at the time. Calculations performed reveal no reportable quantities were exceeded.
No LDEQ Number Available 2011-03-09	Point Source(s): Tank 37T-315 Pollutant(s): None - BRQ	Cause of Problem: Weather STORMS. Excess rainwater accumulated at site during severe rainstorm causing Surge Tank (37T-315) to fill. Tank level gauge malfunctioned indicating level was lower than actual water level causing secondary seal to breach, but letter states that no material was released.	Upon discovering malfunction, operations were shutdown to drain water to another surge tank, which then lowered the level in Tank 37T-315 within an hour and primary seal remained intact. There was no spill nor were there any other emissions exceedances related to this event. They claim that the apparent excursion of the secondary seal general requirement did not cause an emergency condition as defined in LAC 33:I:3905. In addition, Motiva upholds the claim that the incident was due to the occurrence of an upset.
128963 2011-02-01	Point Source(s): Pressure Swing Adsorber Refinery Heaters Pollutant(s): Light Hydrocarbons - BRQ Hydrogen - BRQ Sulfur Dioxide - BRQ	Cause of Problem: Process Upset Flaring due to unplanned shutdown of Pressue Swing Adsorber (PSA) system. Oxygen analyzer on VPS-2 Atm Heater went into alarm due to composition change in fuel gas caused by PSA's startup. Additionally, a malfunctioning pressure controller within the Amine regeneration Unit caused the kick back valve on the amine pump.	BRQ. No information given.