|
National Safety Alert
No. 9
May 25, 2011
SAFETY ALERT
Heater-Treater Fire Forces Evacuation of Platform
A Safety Alert is a tool used by
the Bureau of Ocean Energy Management, Regulation and
Enforcement (BOEMRE) to inform the offshore oil and gas industry
of the circumstances surrounding an accident or a near miss. It
also contains recommendations that should help prevent the
recurrence of such an incident on the Outer Continental Shelf.
In September 2010, a fire
occurred on a production platform during start-up operations
following an inadvertent shut-in. The platform was inadvertently
shut-in when a contract paint crew member unintentionally bumped
the level safety high (LSH) on the glycol contactor. The fire
quickly escalated to the point that all personnel abandoned the
platform and entered the water. All personnel were later
rescued.
A BOEMRE investigation into this
incident revealed that the fire was caused by the collapse of
the forced draft Heater-Treater’s fire tube. Upon the collapse
of the fire tube, hydrocarbons (oil and natural gas) came into
contact with the fire tube’s hot burner, produced flames, and
ignited, eventually ejecting the Heater-Treater’s flange face
assembly approximately 8 to 10 feet away from the front of the
vessel. Oil burst into flames as it flowed out onto the cellar
deck. The fire spread quickly on the cellar deck, and then
spread to the main deck where it reached combustibles and
continued to spread. The platform sustained major damage.
Based on the evidence developed
during its investigation, the BOEMRE investigation concluded
that the fire resulted because the operator failed to adequately
maintain and operate the Platform’s Heater-Treater in a safe
condition. Specifically:
 |
The Heater-Treater’s fire
tube experienced high temperature spikes, sustained
operating heat from regular use and substantial pitting and
corrosion during its nearly 30-year life, which weakened the
fire tube’s steel. Moreover, the Heater-Treater’s normal
operating pressure contributed to the collapse of the
already-weakened fire tube.
|
 |
The Heater-Treater was
designed for a significantly higher production (process
fluid) flow rate than was likely being processed on the
platform at the time of the incident. This meant that there
most likely was not enough liquid being processed through
the Heater-Treater to adequate dissipate heat from the fire
tube and maintain proper temperature;
|
 |
The Operator failed to have
an inspection plan and regularly inspect and maintain the
Heater-Treater, as required by BOEMRE regulations (30 C.F.R.
§§ 250.198, 803(b)), which could have prevented the
incident. |
Furthermore, the BOEMRE
investigation found several safety deficiencies on the platform
on September 2 that posed risks to the crew’s safety:
 |
The Back Pressure Valve (BPV)
controller was improperly assembled and was not adequately
maintained, which caused the BPV to fail to open fully or
fast enough to relieve the gas that packed the high pressure
and low pressure system after the wells were brought back
online. The pressure rose on the blocked system, and the
PSVs on the glycol contact tower and the compressor
activated;
|
 |
Electrical wiring and
associated switch gear components for the firewater pump
were compromised and prevented the emergency diesel
generator from supplying electrical power to the firewater
pump for the required 30 minutes run time, which left the
crew without the means to try and fight the fire;
|
 |
Inadequate monitoring of
relevant essential operating conditions while safety devices
were in bypass, which prevented the crew from taking
appropriate steps in response to an increase in pressure in
the production train. |
BOEMRE recognizes that
Heater-Treaters are essential components used for processing oil
and considers them to be extremely hazardous if not properly
maintained and operated in an efficient manner. Therefore,
BOEMRE recommends the following to Lessees/Operators in the Gulf
of Mexico, the Pacific and Alaska regions that operate
forced-draft liquid hydrocarbon fired components,
i.e. forced draft Heater-Treaters:
 |
Evaluate the capacity and
operating range of the Heater-Treater and related forced draft
burners relative to the amount of oil being produced. If the oil
production rate falls below the designed capacity of the
Heater-Treater, operators should evaluate a variety of options
to ensure that they are maintaining this equipment in a safe
condition;
|
 |
Perform a Hazards
and Operability Study (Hazop Study) of fired components that
process liquid hydrocarbons, and specifically review process
vent piping configurations for safe and adequate venting
capabilities. |
BOEMRE further recommends that
all Lessees/Operators:
 |
Evaluate, and where
necessary, update or develop their inspection plans for
Heater-Treaters as required by BOEMRE regulations (see 30
C.F.R. §§250. 198, 250.803(b)), and regularly inspect
Heater-Treaters;
|
 |
Review their current
procedures on bypassing safety devices with their platform
production crews to ensure that they include effective
monitoring of relevant essential operating conditions when
systems are in bypass to conform to BOEMRE regulations. |
For a full report, see BOEMRE
panel report at:
http://www.boemre.gov/ooc/pdfs/Panel_VR380AMAY23FullReport.pdf.
For further information, please contact Scott Mouton,
Lake Charles District, 337-480-4614. |