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Valero (26003), Norco
Causal Factor: Equipment Failure
| LDEQ Accident Number Accident Date |
Point Source(s) | Notes | Amount of Release |
| 78904 2005-05-07 | Flare 1 EIQ 15-77; Flare 2 EIQ 12-81 | Cause: During startup of unit, one wet gas compressor failed to start as expected due to unanticipated electrical problems. Process gases normally routed through this compressor were diverted to the flare. Followup: No Information Provided Notes: Compressor repaired as quickly as possible.Air filter clogged with debris. Inspection of air filter has been added to preventative maintenance schedule. | Sulfur Dioxide: 13,646.0 pounds Carbon Monoxide: 1,910.0 pounds Nitrous Oxide: 351.0 pounds Particulate Matter: 11.0 pounds Volatile Organic Compounds: 723.0 pounds |
| 78487 ; 78475 ; 78488 2005-04-23 | Flare 1 EIQ 15-77 | Cause: MSCCU wet gas compressors tripped due to problems with common lube oil system. Followup: Yes Notes: Reduced feed rate to MSCCU. Issue involves wet gas compressor as seen before. Follow up report sent on June 6, 2005 with remedies: redesign of the nitrogen regulator and replacement of the pressure controller on the lube oil system | Sulfur Dioxide: 4,292.0 pounds Carbon Monoxide: 588.0 pounds Nitrous Oxide: 108.0 pounds Particulate Matter: 3.0 pounds Volatile Organic Compounds: 223.0 pounds |
| 76674 2005-01-26 | West Plant | Cause: Lost a charge pump on West side of plant Followup: No Notes: Courtesy notice | |
| 92784 2006-12-20 | Transformer T-2, millisecond catalytic cracking unit | Cause: Transformer T-2, which supplies 480 volt power to certain pieces of equipment in the millisecond catalytic cracking unit (MSCCU), had an internal short circuit. This in turn caused unstable operations in the MSCCU resulting in flaring. Followup: Yes Notes: Restored power to the MSCCU and stabilized operations | |
| 91842 2006-11-03 | Thermal oxidizer stack | Cause: Incline mixer for the sulfer recover units' tail gas treating unit malfunctioned. Led to higher Hydrogen Sulfide gas concentrations being send to the TOX causing it to trip. Also, the temperature in the TOX dropped due to both the TOX trip and loss ofheat from the incline mixer. Precise cause of failure is Under Investigation Followup: Yes Notes: Restarted the TOX ASAP so that any residual H2S could be combusted. Restarted the TGU as soon as practical to minimize SO2 emissions. | Hydrogen Sulfide: 629.0 pounds Sulfur Dioxide: 1,315.0 pounds |
| 90110 2006-08-20 | Uninterruptable power supply in East Plant motor control building went out causing electrical system to go into fail safe mode. | Cause: Uninterruptable power supply in East Plant motor control building No. 8 failed and caused the electrical system to go into fail safe mode. Electrical equipment assocaited with boilers shut down resulting in loss of steam pressure throughout the refinery. In turn, other process units shut down. Excess gas from shutting down units was directed to refinery flare system Followup: Yes Notes: Restarted critical equipmt as quickly as possible to return to normal operation. | Under Investigation |
| 86947 2006-03-29 | Millisecond catalytic cracking unit off gas treatment system | Cause: Due to a problem with off gas treatment system, the off gas did not meet the specification for feedstock use. Therefore, the gas was diverted to the flare while we corrected the problem with the treatment system By visual observation, they discovered that there was another source of gas in the flare. A process safety valve had lifted on the HP overhead receiver for the off gas system The PSV did not reseat automatically. Followup: No Notes: Emissions reduced by making adjustments to the MSCCU to reduce the quantity of off gas produced. | Sulfur Dioxide: 3,200.0 pounds |
| No LDEQ Reported 2006-02-21 | None Reported | Cause: Off-gas amine treater was encountering problems that led to a flaring event. Followup: No Notes: Letter states that emissions were BRQ. | |
| 85406 2006-01-26 | None Reported | Cause: Wet gas compressor was encountering problems that could possibly lead to a flaring event. Followup: No Notes: Letter states that emissions were BRQ. | |
| No LDEQ Reported 2006-01-22 | None Reported | Cause: Wet gas compressor was encountering problems that could possibly lead to a flaring event. Followup: No Notes: Letter states that emissions were BRQ. | |
| 85294 2006-01-20 | Uninterrupted power supply system | Cause: UPS system failed causing the power at the DCS consoles to be lost. Resulted in flaring of gases at Flares 1 and 2. Followup: Yes Notes: Emissions were minimized by reestablishing power to the West Plant DCS consolves and reestablishing normal operation as soon as possible. | Sulfur Dioxide: 4,600.0 pounds |
| 85926 2006-01-20 | None Reported | Cause: Off-gas amine treater was encountering problems that led to a flaring event. Followup: No Notes: Letter states that emissions were BRQ. | |
| 84906 2006-01-02 | None Reported | Cause: # 2 Debutanizer was encountering problems that may have lead to a flaring event. Followup: No Notes: Letter states that emissions were BRQ. | |
| 101832 2007-12-19 | #3 Flare | Cause: The Flare Gas Recovery compressors (6-64-101A and 102B) tripped and caused elevated SO2 losses from their #3 flare (EQT 034). Followup: No Notes: Letter states, | |
| 100919 2007-11-09 | EQT 013 and EQT 007 EQT 013 and EQT 007 (Flares #1, 2) | Cause: The Wet Gas Compressor tripped on low oil pressure. Followup: Yes Notes: The incident involved releases on two separate days, 11/09/07 and 11/12/07, but were assigned the same incident Report # by SPOC. | Hydrogen Sulfide: 18.0 pounds Sulfur Dioxide: 2,102.0 pounds Nitrogen Oxide: 11.0 pounds Carbon Monoxide: 125.0 pounds Nitrogen Oxide: 23.0 pounds Volatile Organic Compounds: 47.0 pounds Sulfur Dioxide: 4,559.0 pounds Hydrogen Sulfide: 12.0 pounds Sulfur Dioxide: 2,200.0 pounds Carbon Monoxide: 57.0 pounds Nitrogen Oxide: 11.0 pounds |
| 100919 2007-11-09 | None Reported | Cause: The wet gas compressor tripped on low lube oil pressure. This caused the Coker off gas to relieve to the flare. The cause of this incident is under investigation. Followup: Yes Notes: Emissions were minimized by immediately restarting the Wet Gas Compressor. | |
| 99427 2007-09-13 | No information given. | Cause: The event started around 21:30 on Sept. 13, 2007, when an outlet pipe of the LPG Caustic Prewash Column (V-10-24) failed, causing liquid/vapor LPG (alky feed) to be released to the atmosphere. The system was isolated, and the remaining material vented to the flames at approximately 02:45 on Sept 20, 2007. The depressurization lasted about 3 hrs. Followup: Yes Notes: Remedial Actions: Shut down the upstream unit FCCU (MSCCU), isolated and depressurized the vessel, and replaced the failed pipe. / Pollutants: Some material was entrained in fire water used to suppress the release. The remaining material dispersed into the atmosphere. Fire water was treated at the refinery wastewater treatment plant. | |
| 98939 2007-08-27 | Thermal Oxidizer | Cause: The Thermal Oxidizer for the Sulfur Recovery unit (that oxidizes Hydrogen Sulfide) tripped, and they struggled to restart it. Followup: No Notes: No reportable quantities were exceeded during this incident, so the notification was to be considered a courtesy. | |
| 97330 2007-06-24 | EQT 013 and EQT 007; Flares 1 and 2 | Cause: The wet Gas Compressor tripped on low lube oil pressure. This caused the Coker off gas to go to the flare. The cause of this incident is under investigation. Followup: Yes Notes: Emissions were minimized by immediately restarting the Wet Gas Compressor. | Carbon Monoxide: 37.0 pounds Volatile Organic Compounds: 14.0 pounds Sulfur Dioxide: 1,126.0 pounds |
| 97168 2007-06-17 | Thermal Oxidizer | Cause: The Thermal Oxidizer tripped, resulting in a release of materials to the air. The materials were released to a flare stack but they were not able to get combustion so they went to the atmosphere. Followup: No Notes: Several reportings: The incident lasted 98 minutes, during which Valero tried to start the unit a couple of times... They had been able to relight the Thermal Oxidizer but still could not say at that point if was stable... The Thermal Oxidizer unit had been up and down and attempts to stabilize had failed several times over.... | |
| 96323 2007-05-17 | Thermal Oxidizer #1 (TOX) and Tail Gas Treating Unit | Cause: The Thermal Oxidizer had tripped and this event might exceed or have exceeded reportable quantities of Sulfure Dioxide. Also, the Tail Gas Treating Unit (TGTU) had tripped and there was a possibility of an Hydrogen Sulfide exceedance. Followup: Yes Notes: Restarted the Thermal Oxidizer and the tail gas unit, reset the level set point to compensate the level indicator error, and replaced the faulty level indicator the next day. They have added the level indicator to their monthly preventive maintenance schedule, completed 6/16/2007. **["May 17, 2007 16:00 to 17:00, H2S (lbs/hr) 157.72, permit limit 0.5, TOX Down for 12 minutes (<700F)] | Sulfur Dioxide: 1,400.0 pounds Hydrogen Sulfide: 158.0 pounds |
| 96074 2007-05-09 | Thermal Oxidizer (TOX) #1, Flares #1 and #2 | Cause: On May 9, 2007, Valero shut down its NHT and continuous catalytic reformer (CCR) for repair. While shutting down the units, an additional unit (diesel hydrotreater (HDT)) had to be shut down as well due to lack of hydrogen supply from their third party hydrogen supplier. Thus, they had to shut down their sulfur recovery unit 3700 (SRU) due to insufficient sulfur feed from DHT. When the SRU was down, they kept the reactor hot using hot air sweep, which released SO2 from the sulfur deposited on the reactor bed, through the Thermal Oxidizer. At 9:54, May 15, 2007, they made notifications that the units were stable. Followup: Yes Notes: The incident consisted of NHT, CCR, DHT, and SRU shutdown events. They restarted their SRU as soon as the feed was available. | |
| 94654 2007-03-16 | Thermal Oxidizer #1 (TOX) | Cause: On March 16, 2007, Valero shut down its DHT due to a process heat exchanger leak, and thus had to shut down its SRU, 3700, due to insufficient sulfur feed from the DHT. When SRU was down, they kept the reactor warm using hot air sweep, which release sulfure dioxide from the sulfure deposited on the reactor bed, through the Thermal Oxidizer. On March 19, they brought the DHT and SRU back into service. During the start-up of the DHT, the TGTU (tail gas treatment unit) inline mixer at SRU 1600 tripped, which caused excess SO2 emissions as well. Followup: Yes Notes: The incident consisted of DHT and SRU shutdown and TGTU trip events. In the TGTU event, they restarted the TGTU as soon as possible to minimize emissions. | |
| 93656 2007-02-01 | Thermal Oxidizer | Cause: TOX, which oxidizes H2S to SO2, began to malfunction and cause several shutdowns. Followup: Yes Notes: During periods of prolonged outages, they reduced the refinery throughput in order to minimize the sulfur load to the TOX. | Hydrogen Sulfide: 1,785.0 pounds |
| 93686 2007-02-01 | Thermal Oxidizer (TOX) | Cause: TOX, which oxidizes H2S to SO2, began to malfunction and cause several shutdowns. Followup: Yes Notes: During periods of prolonged outages, they reduced the refinery throughput in order to minimize the sulfur load to the TOX. | Hydrogen Sulfide: 1,785.0 pounds |
| 93265 2007-01-15 | Thermal Oxidizer | Cause: The Thermal Oxidizer, that oxidizes Hydrogen Sulfide to Sulfur Dioxide, had tripped. Followup: No Notes: Letter states, | |
| 93013 2007-01-02 | EQT 013 and Eqt 007 | Cause: An LPG line in the East Plant froze, and excess LPG was received in the feed from the Coker to the NHT Unit. The NHT stripper over-pressured and excess gas was diverted to the refinery flare system. Followup: Yes Notes: The Coker LPG pump was shut down to relieve pressure off of the line and rates to the unit were reduced. The pump was restarted, line service was restored and rates were gradually increased. | Sulfur Dioxide: 5,257.0 pounds |
| 109888 2008-10-07 | TOX 1 and TOX 2 | Cause: failed FBM card leads to 3700 SRU shut down. Followup: No Notes: reduced the crude rate, thereby sulfur load to sulfur units and restarted SRU 3700 as soon as possible. | Sulfur Dioxide: 3,714.0 pounds |
| 109755 2008-10-01 | Flares 1 and 2 | Cause: Hot Separator develops crack allowing material and gases to release. Followup: No Notes: Emissions minimized with a controlled shutdown of the unit. Firewater sprayed on to control vapors and mitigate inflammation. Oil absorbent booms deployed. Water collected by vacuum truck from drainage routes. | |
| 109312 2008-09-18 | Coker Wet Gas Compressor | Cause: Coker Wet Gas compressor tripped on low lube oil pressure when the main lube oil pump turbine tripped. This cause Coker off gas to relieve to the flare. Sulfur dioxide was released from the refinery flares and rapidly dispersed. The cause of this incident is under investigation. Followup: Yes Notes: Emissions were minimized by immediately restarting the Wet Gas Compressor. | Sulfur Dioxide: 3,060.0 pounds |
| 109312 2008-09-18 | Flares 1 and 2 | Cause: coker wet gas compressor tripped on low lube oil pressure when the main lube oil pump turbine tripped. Followup: No Notes: Incident still under investigation; Follow-up letter cites acquisition of facility from Orion again. | Sulfur Dioxide: 3,060.0 pounds |
| 107543 2008-07-26 | Flares | Cause: FCCU lost its air blower and the debutanizers pressurized and relieve to the flares Followup: No Notes: Letter states that emission were BRQ. | Sulfur Dioxide: 192.0 pounds |
| 102759 2008-02-01 | Flares 1 and 2 | Cause: failure of WGC due to low lube oil pressure Followup: No Notes: Emissions minimized by immediately restarting WGC. | Sulfur Dioxide: 7,240.0 pounds |
| 102359 2008-01-16 | #1 Flare | Cause: Vacuum tower lost its vacuum Followup: No Notes: Letter states that emission were BRQ. | |
| 102262 2008-01-13 | Flare | Cause: the blow down system off the Wet Gas Compressor was routed to flare to relieve coke drum pressure after one of the coke drums cracks. Followup: No Notes: Letter states that emission were BRQ. | Sulfur Dioxide: 4.0 pounds Hydrogen Sulfide: 2.0 pounds |
| 102201 2008-01-10 | Flare Gas Recovery Compressor | Cause: Flare Gas Recovery Compressor tripped Followup: No Notes: Letter states that emission were BRQ. | Sulfur Dioxide: 20.0 pounds Volatile Organic Compounds: 1.0 pounds Hydrogen Sulfide: 1.0 pounds |
| 102102 2008-01-06 | Coker Wet Gas Compressor Flares 1 and 2 | Cause: failure of WGC Followup: No Notes: DEQ report states that there have been many WGC failures, enough that they have made repeated calls to the facility urging them to repair the unit to prevent recurrence of such events. According to report, Valero has repaired the WGC. | Sulfur Dioxide: 6,930.0 pounds Volatile Organic Compounds: 72.0 pounds Particulate Matter: 1.0 pounds Hydrogen Sulfide: 19.0 pounds Nitrogen Oxide: 35.0 pounds Carbon Monoxide: 189.0 pounds |
| 102089 2008-01-05 | Thermal Oxidizer #1 (EQT 195 (99-3)) | Cause: TOX 1 for SRU tripped Followup: No Notes: Repeated attempts to rebuild the igniter and restart the THOX | Hydrogen Sulfide: 460.0 pounds |
| 118610 2009-10-09 | Thermal Oxidizer #2 (EQT0195) | Cause: Experienced problems with the 3700 Tail Gas Treatment Unit, which resulted in excess emissions from the associated 3700 Thermal Oxidizer (Thermal Oxidizer No 2). Followup: Yes Notes: No Information Given. | Sulfur Dioxide: 164.0 pounds |
| 118541 2009-10-07 | Fare 1, Flare 2 | Cause: The MSCCU Wet Gas Compressors tripped offline due to a malfunction of their electric and controls systems. Wet gases were relieved through pressure control valves to Flares 1 and 2 in order to maintain safe system pressure. Followup: Yes Notes: Wet gas compressor was restarted. | Sulfur Dioxide: 2,300.0 pounds Hydrogen Sulfide: 6.0 pounds |
| 116428 2009-07-12 | #3 Debutanizer Reflux pump | Cause: At approximately 1:15 operators noticed that the #3 Debutanizer Reflux pump seal had failed and was releasing process gases ti the atmosphere. Seal failure was caused by a failure in the pump's thrust bearing. Followup: Yes Notes: Deluge water was used to contain the vapors and reduce the risk of fire. The malfunctioning pump was isolated and shut down. A redundant backup pump was started to avoid unit shutdown. Reflux pump thrust bearings will be replaced from 40 degree contact bearings to 15 degree contact bearings. | Hydrogen Sulfide: 324.0 pounds Volatile Organic Compounds: 4,988.0 pounds Propylene: 2,195.0 pounds |
| 126165 2010-09-06 | 3700 Sulfur Recovery Unit, 3700 Thermal Oxidizer | Cause: Valve malfunction on 3700 Sulfur Recovery Unit resulted in sulfur dioxide elevated levels at 3700 Thermal Oxidizer. Followup: Yes Notes: RQ. Refinery letter states that the permitted SO2 rate and reportable quantity were exceeded. Workers diverted 3700 SFU feed stream to other Sulfur Recovery units, took manual control, and restarted unit. Refinery letter only; letter states that this is second follow-up report, but no first report is included in file. No LDEQ report. | Sulfur Dioxide: 3,454.0 pounds |
| 126017 2010-08-30 | 3700 Sulfur Recovery Unit, 3700 Thermal Oxidizer | Cause: Malfunction of main air blower on 3700 Sulfur Recover Unit cause elevated sulfur dioxide levels at the 3700 Thermal Oxidizer (EQT 0195). Followup: No Notes: Report states that 6 part remedial action was taken to prevent future incidents, including operator training, equipment repair, and additional administrative controls. Refinery letter only; letter states that this is second follow-up report, but no other letter included. No LDEQ report. | Sulfur Dioxide: 1,165.9 pounds |
| 123734 2010-05-25 | FLARE: MSCCU | Cause: Small hole in Milli-Second Catalytic Cracking Unit (MSCCU)--had to flare when shutting down for repair. FLARE. Followup: No Notes: BRQ. Refinery letter states that no reportable quantities were exceeded. No information given regarding remedial actions. | Hydrogen Sulfide: 21.0 pounds Volatile Organic Compounds (VOCs): 2,010.0 pounds |
| 122132 2010-03-14 | tank T-150-21 | Cause: Vacuum gas oil leaked from tank T-150-21. Tests showed some "soil protective of groundwater" was contaminated but refinery states that groundwater was not actually impacted due to high clay content of the soils. Followup: Yes Notes: BRQ. Refinery letter states that no reportable quantities were exceeded. Tank in question drained, adjacent dike containment area vacuumed. | |
| 121517 2010-01-31 | West Plant oil sump | Cause: Separation sludge released from oil/water separator in the West Plant--oil sump overflowed. "Petroleum Refinery Float," RCRA code F038, Hazardous Waste. Followup: No Notes: RQ. Vacuum trucks mobilized to pump down overflowing sump and recover visible material. Booms & pads placed around spill, pumps upstream shut off, sump closed & barricaded after cleanup, contaminated soil scraped down (about top 2"). Incident communicated to affected personnel; prevent unauthorized access to control systems; level indication for sump updated from mechanical to radar type; add impervious secondary containment area around sump; evaluate other oily sewer containment systems for mitigation of overflows. | F038 Hazardous Waste: 1,300.0 gallons |
| 131491 2011-05-27 | 1600 TOX | Cause: Due to failure of a pressure relief device, the refinery's 1600 TOX tripped and resulted in elevated sulfur dioxide levels. They estimate that the reportable quantities for sulfur dioxide were exceed around 10:45 am on 5/27/11. Based upon a failure analysis conducted by the manufacturer, it is believed that the device experienced an instantaneous pressure increase which cause the device to burst below the marked burst pressure. Followup: Yes Notes: Operators blocked in the process line with the malfunctioned device and restarted the TOX. The following corrective actions have been identified to prevent recurrence of this incident: (1) Develop Installation Guidelines, based upon manufacturer recommendations, to ensure devices are properly installed in the field (2) Develop Operating Guidelines, based upon manufacturer recommendations, for controlling the pressurization rate seen by the device through proper valve operation (3) Conduct training with Maintenance and Operations personnel on the two above established guidelines. The permitted maximum hourly sulfur dioxide rate and reportable quantity were exceeded. The concentration limit (250 ppm/ 12 h) was not exceeded. | Sulfur Dioxide: 973.0 pounds |
| 130162 2011-03-24 | 3700 SRU Malfunction | Cause: The sulfur dioxide levels at the 3700 Thermal Oxidizer (EQT 0195) were intermittently elevated from approximately 3/24/11 from 8:40 am until 11:30 am. Valero estimates that the reportable quantity for sulfur dioxide was exceeded at 9:25 am. This event was attributed to a miscommunication between night and day-shift operators, as well as process pressure controller that needed calibration (tuning). Followup: Yes Notes: Operators moved quickly to make manual control over automatic control valves that may have contributed to this event. Operational moves were conducted on a separate sulfur recover plant to help stabilize the upset. The following measures have been identified to help prevent recurrence:(1) Tune pressure controller for amine acid gas header to 3700 SRU (2) Communicate incident and reinforce the use of shift notes when communicating important details | Sulfur Dioxide: 1,573.0 pounds |
| 144411 2012-11-05 | Flare 1 and 2 | Cause: The wet gas compressor in the delayed coking unit had malfunctioned. Followup: Yes Notes: The maximum hourly permitted emissions for hydrogen sulfide and sulfur dioxide exceeded the maximum hourly permitted emissions. Gas from the coker was combusted in Flare 1 and Flare 2. The resulting combustion byproducts rapidly dispersed. Emissions were minimized by restarting the wet gas compressor. The incident will be communicated to all affected personnel. The XY-53325 A and B solenoids as well as the XY-53325A relay will be replaced during the text outage. Wiring in the compressor control cabinet will be upgraded to separate critical wiring from general purpose wiring. | Carbon Monoxide: 137.0 pounds NOx: 25.0 pounds Particulate Matter: 1.0 pounds Volatile Organic Compounds (VOCs): 1.0 pounds Sulfur Dioxide: 3,142.0 pounds Hydrogen Sulfide: 8.0 pounds |
| 143663 2012-10-08 | NIG | Cause: The Hydrotreater Hydrocracker (HTHC) unit had malfunctioned resulting in excess SO2 emissions at Flares 1 and 4. A feed pump motor shutdown due to an inboard bearing failure causing all four of the HTHC heaters to trip. When the HTHC heaters tripped, the LCO reactor lost its heat input to the top of the hydrotreating bed. With the loss of the heat input, the quench valve automatically began to close with the change in the bed inlet temperature causing less hydrogen to be fed into the stream creating a change in the hydrogen/oil ratio and ammonia in the vapor phase. In addition, there was tray damage in the LCO reactor causing flow maldistribution which compounded the issue. Thus, the change in composition and flow maldistribution caused increased cracking and significant temperature increase in a subsequent bed. The temperature increase in the subsequent bed activated the high rate depressurization of the HTHC unit. Followup: Yes Notes: Gas from the HTHC was combusted in Flare 1 and 4 and the resulting combustion byproducts rapidly dispersed. A quantity of the material was recovered through the fuel gas recovery unit on the flare system. The reportable quantity for SO2 was exceeded as a result of this incident. In addition, the max hourly permitted emissions for SO2 were exceeded at Flares 1 and 4. Operations will implement a guidance document to reduce set points by 15 degrees Fahrenheit on loss of LCO charge heater. Cracking beds operation stability will be improved by limiting the temperature delta. A high priority alarm to the DCS will be added. The logic in the DCS will be revised to eliminate the inlet temperature trips. | Sulfur Dioxide: 1,718.0 pounds |
| 143284 2012-09-13 | Tail gas incinerator on the 3700 sulfur recovery unit | Cause: Malfunction of the tail gas incinerator on the 3700 sulfur recovery unit caused the release of 29 pounds of hydrogen sulfide gas. Followup: No Notes: Initial correspondence between the refinery and Louisiana DEQ indicate an original estimate of a release of 100 pounds of hydrogen sulfide, which was later corrected as 29 pounds of hydrogen sulfide (below the reportable quantity). | Hydrogen Sulfide: 29.0 pounds |
| 141595 2012-07-27 | wet gas compressor | Cause: The wet gas compressor in the delayed coking unit malfunctioned resulting in excess H2S and SO2 emissions at Flares 1 and 2. Followup: Yes Notes: On the day of the incident, the steam control valve that regulated the turbine speed for the Coker WGC to account for increased gas flow rates due to an upstream process upset. When this upset was corrected, the gas flow to the WGC decreased and operators began closing the steam control valve for the steam turbine to reduce the speed of the WGC due to this lower gas flow. However, the steam control valve did not provide adequate response and did not result in a change in turbine speed. The WGC ultimately shutdown when the turbine reached its protective overspeed trip point and stopped all steam flow to the turbine. This happened very quickly and no further adjustments to the steam control valve before the turbine tripped. Emissions were minimized by restarting the wet gas compressor. This incident will be communicated to all affected personnel. The facility will install a control clamp at 80% on the steam control valve output to prevent a delayed control response due a dead band on the valve. A team will also be created from operations, controls, process, and reliability to monitor and record events in the Trilogger and review with the process control design team on a biweekly basis to control performance and tune as necessary. There is a discrepancy regarding the incident date. The subject lists the incident date as 07/27/2012, while the written notification states that it occurred on June 27, 2012. | Carbon Monoxide: 667.0 pounds NOx: 62.0 pounds Particulate Matter: 2.0 pounds Volatile Organic Compounds (VOCs): 2.0 pounds Hydrogen Sulfide: 17.0 pounds Sulfur Dioxide: 6,024.0 pounds |
| 141519 2012-06-25 | bulk air valve on the 3700 sulfur recovery unit furnace | Cause: SO2 was released due to a malfunction of the bulk air valve on the 3700 sulfur recovery unit furnace. Followup: No Notes: In a previous report that LABB does not have access to, this release was classified as reportable quantity; however, after further consideration, it was determined that no reportable quantity had been exceeded. 304 pounds of SO2 was released and will be captured in the semiannual deviation report. Discrepancy with the incident date. The subject information states the incident date as 07/25/2012, while the report says June 25,2012. The report does not state whether the previous notification was verbal or written. If it was verbal, and this incident occurred on June 25, the report would have been made more than 7 days after the incident occurred. | Sulfur Dioxide: 304.0 pounds |
| 140457 2012-06-13 | wet gas compressor | Cause: The Wet Gas Compressor malfunctioned when operators were warming Coke Drum D. Shortly after switching to Coke Drum D, pressure on the unit spiked and the Fractionator overhead became overloaded. The temperature increased 20 degrees and caused the Interstage drum to become overwhelmed with condensing liquid. The compressor tripped on high interstage level resulting in flaring. Followup: Yes Notes: As a result of this incident, the maximum hourly combined permitted emissions for H2S and SO2 were exceeded as well as the reportable quantity. Emissions were minimized by restarting the wet gas compressor. The facility will now hold an operations stand down with each shift to review the incident and stress the importance of following all standard operating procedures. The facility is also adding a line to the console check sheet to verify that the tap water is blocked in before warming up drums prior to switching drums. | Carbon Monoxide: 60.0 pounds NOx: 11.0 pounds Volatile Organic Compounds (VOCs): 23.0 pounds Sulfur Dioxide: 1,037.0 pounds Hydrogen Sulfide: 3.0 pounds |
| 140445 2012-06-12 | 3700 SRU TGTU inline mixer | Cause: A malfunction of the 3700 sulfur recovery unit (SRU) tail gas treater unit (TGTU) inline mixer occurred resulting in excess sulfur dioxide emissions. Followup: Yes Notes: Excess sulfur dioxide emissions resulting from the 3700 SRU TGTU inline mixer malfunction were emitted through the 3700 TOX stact to the environment and rapidly dispersed. The 3700 SRU TGTU inline mixer was restarted. Measures to prevent recurrence will be identified as part of a pending investigation. Initial reports indicated that this release was reportable quantity, but a report sent on June 26th, 2012 indicates that no reportable quantity has been exceeded. Emissions associated with this malfunction event were 450 pounds of SO2 and will be captured in the semiannual deviation report. | Sulfur Dioxide: 450.0 pounds |
| 140250 2012-06-05 | wet gas compressor | Cause: The wet gas compressor in the delayed coking unit malfunctioned resulting in excess H2S and SO2 emissions at Flares 1 and 2. Followup: No Notes: Gas from the coker was combusted in flare 1 and flare 2 and the resulting combustion byproducts rapidly dispersed. Emissions were minimized by restarting the wet gas compressor. The incident is still under investigation. No procedures or preventative measures have been identified at this time. | Carbon Monoxide: 54.0 pounds Nitrogen Oxide: 10.0 pounds Volatile Organic Compounds (VOCs): 20.0 pounds Sulfur Dioxide: 1,160.0 pounds Hydrogen Sulfide: 3.0 pounds |
| 140182 2012-06-01 | 3700 TOX thermal oxidizer | Cause: A malfunction of the 3700 thermal oxidizer (TOX)occurred resulting in excess sulfur dioxide emissions. Followup: No Notes: Excess sulfur dioxide emissions resulting from the TOX malfunction were emitted through the 3700 TOX stack to the environment and rapidly dispersed. The 3700 TOX was restarted. Measures to prevent recurrence will be identified as part of a pending investigation. | Sulfur Dioxide: 686.7 pounds |
| 139226 2012-04-30 | Wet gas compressor | Cause: The Wet Gas Compressor in the delayed coking unit at Valero St. Charles Refinery malfunctioned resulting in excess SO2 emissions at flares 1 and 2. Followup: Notes: Refinery fuel gas was combusted in Flare 1 and Flare 2 and the resulting combustion byproducts rapidly dispersed. Emissions were minimized by restarting the wet gas compressor. This incident is still under investigation. No procedures or preventative measures have been identified at this time. | Carbon Monoxide: 56.0 pounds NOx: 10.0 pounds Volatile Organic Compounds (VOCs): 21.0 pounds Sulfur Dioxide: 768.0 pounds Hydrogen Sulfide: 2.0 pounds |
| 137347 2012-02-20 | FLARE: Unspecified flare coming from PSVs on compressors K-14-02A and K-14-02B | Cause: Hydrocarbon flaring was coming from PSVs located on compressors K-14-02A and K-14-02B in the Alkylation unit. Followup: No Notes: Fenceline monitoring was conducted to determine impacts to surrounding areas. The results of monitoring are contained in an attachment to the file. The attachment shows no impact. | |
| 151623 2013-10-14 | 1600 Sulfur Recovery Unit | Cause: On Monday October 14, 2013, at approximately 14:15 hrs, we made notification that we potentially exceeded a reportable quantity for sulfur dioxide due to a malfunction of the 1600 sulfur recovery unit (SRU). After further investigation, we have determined that no reportable quantity has been exceed resulting from this incident. Followup: Notes: Air monitoring conducted with the refinery and along the fence line of the refinery downwind of the prevailing wind direction revealed no appreciable SO2 concentrations (0 ppmv SO2). Report states that excess emissions will be captured in a future Title V report. | Sulfur Dioxide: 49.2 pounds Hydrogen Sulfide: 0.3 pounds |
| 149332 2013-06-21 | Dock 2 | Cause: On June 21 at approximately 17:30 while loading to a barge at dock 2, approximately 30 gallons of Heavy Coker Gas Oil was spilled to the Mississippi river due to a malfunction of the loading arm. The failure occurred because the locking pin on the loading arm was engaged while transferring product to the vessel. The loading arm and counterweight could not move freely with the vessel. The locking pin is spring loaded and held out of the path of the counterweight with a small diameter wire. The wire failed and allowed the locking pin to become engaged. As the vessel was filled, the weight of the oil caused it to sit lower in the river and caused the loading arm to separate from the connection to the vessel.
A weld failed on a 12" pipe located at the base of the loading arm which caused a 1/5" wide by 5" long hole in the pipe. Coker gas oil sprayed 10 feet from the facility and onto the barge. Followup: Yes Notes: All valves were isolated and the transfer was shutdown to prevent additional leakage. Absorbent pads and boom were used to capture any remaining oil. The contracted emergency response vendor was mobilized to assist with the cleanup. The following corrective measures have been or will be implemented to prevent this recurrence: 1) Modify locking pin mechanism so that it is not spring loaded with an engineered connection threaded rod device, 2) Review incident with all Complex 1/SGS (dock operators) personnel for improved hazard recognition, 3) Review inspection procedures with dock personnel including frequency and documentation, 4) Develop a way for SGS operators to have access to input work notifications in SAP, 5) Have a meeting with the North Wind Fab Inc. to incorporate loading arms into the inspection system and ensure all locking pin mechanisms are included in the inspection report. | Heavy Premium Coker Gas Oil: 30.0 gallons |
| 146196 2013-01-21 | Flare 1 and 2 | Cause: The wet gas compressor in the delayed coking unit had malfunctioned.
The Wet Gas Compressor (WGC) malfunction resulted from a malfunctioning lube oil turbine. The nigh prior to the incident, the lube oil turbine tripped. The backup electric pump started in "auto" to control the lube oil pressure. We restarted the lube oil turbine but were unable to shutdown the backup electric pump with the switch in 'auto'. We verified that the lube oil pressure was stable and then shutdown the electric pump. The lube oil turbine then tripped on overspeed and when we switched the backup electric pump from 'off' to 'auto' it did not restart causing the WGC compressor to trip from low lube oil pressure. We determined that the electric pump did not restart because it received a single pulse start signal that was sent before the pump was put in 'auto' causing it not to register. Additionally, the original overspeed trip was due to scoring on the Fischer actuator due to its tendency to side load. The scored piston caused the actuator to stick resulting in a lack of speed control. Followup: Yes Notes: The maximum hourly permitted emissions for hydrogen sulfide and sulfur dioxide at flares 1 and 2 were exceeded. The reportable quantity for sulfur dioxide was also exceeded. Emissions were minimized by restarting the wet gas compressor. Gas from the coker was combusted in Flare 1 and Flare 2, and the resulting combustion byproducts rapidly dispersed. | Carbon Monoxide: 217.2 pounds NOx: 39.9 pounds Particulate Matter: 1.4 pounds Volatile Organic Compounds (VOCs): 1.6 pounds Sulfur Dioxide: 5,558.7 pounds Hydrogen Sulfide: 14.8 pounds |
| 159934 2014-11-09 | Hydrocracker-Hydrotreater | Cause: On 11/9/14 at approximately 21:30 hours, the Hydrotreater-Hydrocracker (HTHC) Recycle Compressor malfunctioned, which initiated a shutdown of HTHC and led to a reportable quantity of sulfur dioxide. The cause of the malfunction is under investigation. Followup: No Notes: Emissions were minimized by shutting down and then restarting the HTHC unit. Air monitoring was conducted in the downstream wind direction within and around the refinery. The incident is still under investigation to determine preventative measures. | Sulfur Dioxide: 1,597.8 pounds Carbon Monoxide: 13.7 pounds NOx: 4.0 pounds Particulate Matter: 0.1 pounds Volatile Organic Compounds (VOCs): 17.9 pounds Hydrogen Sulfide: 8.6 pounds |
| 157325 2014-07-09 | EQT 0360 Flare No. 4 | Cause: The Hydrotreater/Hydrocracker (HTHC) recycle compressor malfunctioned, which initiated a shutdown of the HTHC and led to a reportable quantity of sulfur dioxide. The cause of the malfunction is under investigation while the unit is being repaired. Permitted emissions for H2S, VOC and SO2 was exceeded for 1 hour.
The unit depressured in approximately 15 minutes, however, due to the excess production of hydrogen following the HTHC shutdown, Valero continued to flare hydrogen. Valero submitted a Notification of Case by Case insignificant activity on July 11, 2014 to cover emissions from Hydrogen flaring; therefore, hydrogen flaring was not considered within the duration of this event.
Valero exceeded hourly permitted emissions for hydrogen sulfide, volatile organic compounds and sulfur dioxide at Flare 4 for one hour. Followup: Yes Notes: Shutdown of HTHC unit. Air monitoring was conducted downwind of the refinery. No procedures or preventive measures given at the time of the report. Follow up report lists the following measures identified to prevent recurrence: 1) Review this incident with affected personnel and attach sign off sheet 2) Investigate installing knock out put upstream on dry gas seal (DGS) panel inlet filters with continuous blowdown 3) Investigate the need for level indication and drains on the make-up gas (MUG) discharge pulsation dampers 4) Use recycle gas to supply panel when sufficient differential pressure is available and modify procedures accordingly 5) Evaluate the functionality of the TriLogger system and determine if upgrades are needed 6) Review the lubrication program for HTHC compressors 7) Run drain lines from the dry gas seal panel filters to a safe location for liquid removal | Hydrogen Sulfide: 8.6 pounds Carbon Monoxide: 13.6 pounds Nitrous Oxide: 8.1 pounds Particulate Matter: 0.1 pounds Volatile Organic Compounds (VOCs): 17.9 pounds Sulfur Dioxide: 1,597.7 pounds |
| 157159 2014-07-01 | 3700 Sulfur Recover Unit | Cause: The 3700 Sulfur Recover Unit (SRU) furnace main air safety shutdown valve closed unexpectedly, which initiated a 3700 SRU trip and led to excess emissions of sulfur dioxide. While troubleshooting the malfunction, operators shifted the amine acid gas feed (AAG) from 3700 SRU to two remaining units (1600 and 30 SRU). The move caused excess emissions from the 30 SRU while stabilization was in process. About 30 minutes later, the malfunctioning valve reopened, reintroducing AAG into SRU 3700 and causing a RQ emission for sulfur dioxide.
Later in the same day, at approximately 20:45 the 3700 SRU reaction furnace main air safety shutdown valve closed again. After the second malfunction, Valero purposely shut down the 3700 SRU in order to further troubleshoot the issue, and then implemented sulfur shedding in order to reduce sulfur loading to the SRUs. Sulfur shedding included: decreasing throughput of the Hydro-Treater, Hydro-Cracker (HTHC) unit to minimum rates, reducing overall refinery crude throughput, shifting amine acid gas feed to the two remaining operating SRUs (1600 and 30 SRUs), and shutting down sour water acid gas feed (SWAG) to the remaining two SRUs. The quick shift in AAG feed to the remaining two SRUs resulted in excess emissions from the 30 and 1600 SRUs for approximately 1 hour while making the necessary adjustments for the increased AAG loading to the units.
The additional loading at the 30 SRU caused the 30 Thermal Oxidizer (TOX) to trip offline at 21:52 hrs due to low oxygen for combustion. It was brought back online at approximately 23:32. However, during the outage Valero experienced elevated hydrogen sulfide emissions from the 30 TOX. When the 30 TOX tripped, they had trouble restarting it due to wires that were found to be corroded and detached from the terminated position. The wire was tied to a system that was needed to complete the logic to start the TOX. The corroded wires were repaired, the termination box was properly sealed and the TOX was restarted.
An investigation into the SRU 3700 reaction furnace main air safety shutdown valve malfunction revealed a loose wire as the cause. Valero repaired it, restarted the 3700 SRU, and resumed normal operation. Followup: Yes Notes: Emissions were minimized by shutting down the 3700 and reducing the feed to upstream operating units. Subsequently, repairing and restarting the 3700 SRU reduced sulfur loading on the 30 and 1600 SRU, which allowed those units to resume normal operation. Air monitoring was conducted in the downstream wind direction within and around the refinery, and no detectable SO2 or H2S was found using portable air monitoring equipment. The following corrective actions were identified: 1) Review the incident with all affected personnel 2) Review the requirement to evaluate the condition of the sealing system of any instrument enclosure that is opened while performing any maintenance task associated with routine or preventative maintenance 3) Remove the logic for the 30 SRU atomizing stream valve from the purge permissive and pilot permissive. | Carbon Monoxide: 10.3 pounds NOx: 1.9 pounds Particulate Matter: 0.1 pounds Volatile Organic Compounds (VOCs): 33.2 pounds Sulfur Dioxide: 21.7 pounds Hydrogen Sulfide: 0.1 pounds |
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