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Motiva Enterprises (2719), Convent

Releases of Nitrogen Oxide

LDEQ Accident Number
Accident Date
Point Source(s) Notes Amount of Release

Steam Boilers 31F-801, 31F-802, 31F-803, 31F-805, and 31F-810
Cause: Steam Boiler 31F-810 tripped (shutdown) at approx 03:56 In order to stabilize and maintain the refinery steam system, the firing rates and subsequent steam production from 801, 802, 803, and 805 boilers were increased and adjusted over the next 35 hours. Maintaining the refinery steam system is critical in continuing the operation of process units and potentially preventing environmental incidents from any abrupt unit shutdown or malfunction. The 810 boiler shutdown when erratic air flow readings into the boiler were detected because ambient conditions caused false pressure readings on the air flow monitors, which, in turn, caused the forced draft fans to shutdown. The shutdown of the forced draft fans initiated an instrment protective func

Followup: Yes

Notes: [Final report] Immediate action was taken to ensure the safe operability of the 810 boiler, and the process for restarting the boiler began as soon as all safety and operability concerns were addressed. The 810 Boiler was refired and began producing plant steam on the afternoon of 12/25/05, and the normal operation of steam boilers resumed and excess Nitrogen Oxide emissions ceased. For the 810 Boiler, a project s being implemented to install a more reliable air measurement device, which will be finalized once proven over the operating range of the boiler. The operating constraints for 801, 802, 803, and 805 Boilers are being updated to reflect the environmental requirements for those boilers"
92.0 pounds

HTU-2 Fire and Release from recycle Compressor
Cause: At approximately 10:25 am on 10/29/05, there was a small fire on 14C-201 recycle compressor on HTU-2. A small fire was ignited by lube oil escaping the seals on the turbine outboard bearing cap onto the turbine case which was in full operation during the leak. It appears that the lube oil reservoir overfilled which impeded flow through the lube oil return line back to the reservoir.

Followup: No

Notes: The fire was immediately extinguished by operations using a fixed fire monitor. Due to the fire the hydrogen system on the unit had to be depressured to the flare resulting in flaring for several minutes. The unit was depressured for repair. Incident is under investigation using Triangle of Prevention program. Mitigations are likely to be a combination of engineering, i.e. different technology for measuring levels and revising procedure No reportable quantities were exceeded.
5.8 pounds

Flares 1 and 2
Cause: Related to Hurricane Rita but no information given

Followup: No

Notes: telephone report have estimated exceedances of Sox Nitrogen Oxide Hydrogen Sulfide and Volatile Organic Compoundss

Mississippi River Docks 1&2 Fire Water Pump 33G-5 and 33G-4
Cause: Experiencing problems with electric and diesel raw water pumps and need to use fire water diesel pumps to supply raw water to raw water treatment plant.

Followup: No

Notes: Are developing a tracking system to monitor more closely the operation of all diesel fired equipment. Dock 1 electric pumps are scheduled to be replaced with new pumps by the end of 2005. The site has received from the LADEQ an air permit variance to cover the emissions from these pumps for the remainder of 2005.
18,141.0 pounds

Pump 14P-305
Cause: At approximately 7:35 pm smoke was observed coming from the HTU-2 area. Unit operations personnel subsequently discovered a fire on pump 14P-305 originating from the pump's outboard seal.

Followup: No

Notes: The event was localized in the refinery. Pump was isolated from associated process units so as not to affect unit operations. No reportable quantities were exceeded.
5.1 pounds

Valve in the H-Oil Unit and associated Flares
Cause: see notes. Vaccum residuum and gas oil release form valve in H-Oil Unit

Followup: No

Notes: The liquid hydrocarbon released was contained in the unit's concrete slab and did not reach the soil outside of the unit. The flaring related to the incident will continue until the unit has been safely restarted.

Trip of a recycle gas compressor in the H-Oil Unit and resulting flares
Cause: No information given

Followup: No

Notes: Courtesy notice.

Flare No. 2 EIQ No. 19AH-901
Cause: FCCU Wet Gas compressor shut down due to gas turbine overspeed. The servo has been sent out to identify the cause of failur

Followup: Yes

Notes: The servo valve was replaced and the unit restarted. [Follow-up report to telephone report on 2/13/06]
1,747.0 pounds

Steam Boiler EPN 31F-810
Tail Gas Treatment Unit No. 4 Incinerator Stack EPN 78H-101
VPS-2 Atmospheric Tower Feed Heater EPN 83H-101
Cause: The seal on a diesel circulation pump on VPS-2 (a crude distillation unit) failed as a reslut of a suspected bearing problem. This seal failure caused the release of approximately 434 bbls of untreated (sour) diesel, which ignited, resulting in a fire.

Followup: Yes

Notes: Motiva has slowed down production throughout the refinery until investigations are complete. Inspected, repaired, and rebuilt the pump as necessary. W/r/t pump seal failure, rotating equipmt and other personnel will complete the investigation and implement necessary changes to monitoring, inspection, and maintenance procedures
437.0 pounds

Tail Gas Treating Unit 3 (77H-101)
Tail Gas Treating Unit 4 (78H-101)
Flare No 3 (19G-301)
Cause: Upset of the ebulated-bed residuum hydrocracker (H-oil Unit) with a series of fluctuating alarms. While responding to the alarms, operators noticed a fire on the compressor turbine casing and immediately responded to extinguish the fire. The primary cause of this event was a H-Oil unit malfunctioning local level controller on the sour oil seal pot causing the drain valve to remain open and lose reference gas pressure across the seal oil pot.

Followup: Yes

Notes: FIRE. Operations began to reduce production by reducing charge rates on units and to troubleshoot H-Oil recycle compressor and fin fan malfunctions. Immediate action was taken to begin the process of stabilizing, slowing down and shutting down the H-Oil unit and other units as necessary. Affirmative defense letter. Motiva inspected and completed insrumentation checks on the level control for thesour oil seal pots the level control drain valve and the level gauge. A faulty high-level switch was found and replaced. COR will schedulean operation's monitoring cycle to ensure proper sour oil seal pots level. COR will also add a level control loop for the sour oil seal pots levels during the next maintenance outage.

flare no. 2 and wet gas scrubber
Cause: Regenerated Catalyst Slide Valve (RCSV) of the Fluid Catalytic Cracking Unit (FCCU) changed position without a corresponding command from the control system causing trip of the gas turbine driving the Wet Gas Compressor because of high exhaust temperature--overpressure control valve opened to flare. Exceeded RQ's.

Followup: Yes

Notes: "Took immediate action to begin the process of stabilizing, slowing down, and diverting feed from the FCCU riser." Circuit board replaced, cleaned the servo and will replace it when spare arrives.
333.0 pounds

Flare 1-4, TGTU-1,3,4 Incinerator, HTU-1 HSR Reboiler, Boiler #1, Boiler #2, Boiler (EQT0037)
Flare 1-4, TGTU- 1,2,3,5 Incinerator,
Flare 1-4
Cause: This incident involved an upset of the refinery due to a loss of power to the site from our energy supplier's system. Several operating units were affected by the power loss which caused emissions of sulfur dioxide and hydrogen sulfide from the release and combustion of hydrocarbons at the Motiva Enterprises LLC (Motiva) - Convent Refinery.

Followup: Yes

Notes: Immediately, the operating units were stabilized to reduce the impact from the emissions. Several operating units were shutdown and remaining online units followed the emergency procedure for steam load shedding to minimize emissions. Exceeded the 500-pound (lb) reportable quantity (RQ) for sulfur dioxide (SO2). SO2 maximum lb/hr emission limits were exceeded at Tail Gas Treating Units 1, 3, and 4, the Flare CAP, and at combustion devices (i.e. heaters) burning refinery fuel gas. Hydrogen Sulfide (H2S) maximum lb/hr emission rates were exceeded at Tail Gas Treating Units 1, 2, 3, and 5, and at the Flare CAP. The maximum lb/hr emission rates of NOx, CO, VOC, and PM were experienced at the Flare CAP. Lastly, the maximum opacity limit as required by LAC 33:III.1101.B for SRU No. 4 TGTU Incinerator Stack was also exceeded at the time of the incident.
205.2 pounds