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Motiva Enterprises (1406), Norco

Releases of Nitrogen Dioxide

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

Olefins Flare (EPN 6-84)
Cause: On November 13, 2012 at 08:45 hours, Motiva's Diesel Hydrotreater (DHT) flared vent gas to Shell Chemical's OL-5 elevated flare. This flaring was due to the DHT vent gas compressor (K-5337) tripping as a result of a high liquid level in the stripper's overhead accumulator (PV-1987) and in the compressor's interstage knock out pot (PV-1988). In addition, the DHT's recycle compressor (K5339) tripped due to high level in the recycle gas compressor knock out pot (PV-2028).

Followup: Yes

Notes: No remedial actions were given. The flaring occurred at Shell Chemical East, but was caused by a compressor tripping at Motiva Enterprises Norco Refinery's Diesel Hydrotreater (DHT) unit. No reportable quantities were exceeded; however the permitted limits for sulfur dioxide were exceeded as a result of this release. Only gives the total VOCs released in the Permitted Source Emissions table; no breakdown per chemical even though they stated some of the released VOCs in their written notification (ethane, hydrogen sulfide, isobutane, methane, n-butane, and propane). SPOC states that 6000-7000 lbs per hour were sent to the elevated flare, and with a 99% flare efficiency it only resulted in 32 lbs of hydrocarbons being released per hour.
2.1 pounds

1-90(GO-1 Elevated Flare, FE-602)
RCCU Elevated Flare (EPN 8-84), 1-90(GO-1 Elevated Flare FE-602)
Cause: On January 5, 2013, Motiva's Residual Catalytic Cracking Unit (RCCU) discovered a catalyst leak from a section of piping on the unit's West Secondary Cyclone Dip Leg. Operations responded immediately and worked to isolate this section of line. However, due to the location of the leak it was determined the line could not be isolated without shutting down the RCCU process unit. RCCU Operations then initiated a controlled unit shutdown following all operating and safety procedures. As part of the RCCU shutdown process, catalyst circulation within the West Secondary Cyclone Dip Leg was halted and the leak stopped. During this event, GO-1 flared RCCU Dry Gas at the GO-1 Elevated Flare (EPN 1-90) on January 6, 2013, January 9, 2013, and January 10, 2013. The GO-1 flaring resulted in reportable quantities exceeded during the release for Sulfure Dioxide and permit limit exceeded of Hexane on January 9, 2013 and January 10, 2013. Emission Calculations were performed using process data and appropriate AP-42 emission factors. Final update report 4/10/13 corrects cover letter of 3/7/13 report, which inaccurately stated that no reportable quantities were exceeded.

Followup: Yes

Notes: Immediate remedial actions: Operations worked to identify the source of the leak and made preparations for a repair. RCCU operations initiated a controlled unit shutdown to allow for maintenance repairs. As part of the RCCU shutdown process, catalyst circulation within the West Secondary Cyclone Dip Leg was halted and the leak stopped. Once this system was secure, Motiva contract maintenance personnel began welding repairs at the catalyst leak point. On January 8, 2013, the weld repairs on this system were completed and the system was returned to service. Motiva operations restarted the RCCU process unit following all operational and safety procedures on January 14, 2013. Additionally, there were no reportable quantities exceeded during the release. However, the maximum pound per hour limit for sulfur dioxide, carbon monoxide, nitrogen oxides, volatile organic compounds and particulate matter were exceeded. All materials routed to flare were combusted with an appropriate destruction efficiency of 99.5%, released from the RCCU Elevated Flare to the atmosphere, and dispersed naturally. To prevent recurrence of the incident, a field weld was made as a final repair to the leak. A release at Shell Chemicals resulted in flaring at the Shell facility as well as the Motiva facility. Motiva states that the flare release was not a reportable quantity, while Shell's release was.
4,500.4 pounds