Vent Versus Flare in 

GOM OCS

A Perspective of the 

Offshore Operators Committee

March 30, 2011 BOEMRE Offices

New Orleans, LA
Topics of Discussion

• Offshore Operators Committee (OOC)

– Who are we & What do we do? Historical Role we P– Past Collaborative Efforts– Addressing Changes in Venting and Flaring– Current Regulatory Requirements

• Vent vs. Flare Considerations

– Current Industry Practices– What Drives the Decisions– Environmental Considerations and Design Goals

• New vs. Existing Infrastructure

– Changes that might be Necessary– Costs and Scheduling Estimates– Comments, Suggestions and Recommendations
Offshore Operators Com

Who are we? Who are we?

• Non Profit Trade Organization• Focused on GOM Operational Issues• Our GOM Member Companies represent:

– 96% of Oil and Gas Production– 90% of Leases Operated– 85% of Wells Drilled– 84% of Facilities Operated

• 69 Member Companies • 71 Associate Members
Offshore Operators Com

What do we do? What do we do?

Work with Industry, Government Agencies, BOEMRE, USCG, EPA, and other trade orgon issues affecting operations on the OCS, 

• Participate in the development of Operationa

Standards and Recommended Practices;

• Perform Technical Studies;• Comment on Agency Rulemakings;• Sponsor / participate in workshops and confe• Conduct Industry surveys• Host Stakeholder events on OCS issues• Work with other trades to address operationa
OOC/API-BOEM 

Past Collaborative Effo

• Joint sponsorship of key workshops:

– SEMP, Crane Safety, Subpart J and K, Hurricane Prepared

Incident Reporting, Surface Preparation and Coatings

• Development of significant Industry API 

– Security - RP 70, Mooring/Site Evaluation 95 J & F, 2SK, M

Criteria Development, Facilities Assessment, Management Sustained Casing pressure - RP 90, Surface Preparation & TB 91, Helidecks - RP 2L

• Scientific studies to support offshore ac

– Deep Spill Research – fate and effect of deepwater release

Explosive removal of structures, Marine mammal sound issSynthetic based mud sea-bed survey, Hypoxia Study, Mercmarine environment, Mooring JIP, BOP Reliability Study 
OOC/API-BOEM 

Current Efforts

• Rigs to Reef Workshops• MARPOL – Transport of SBM• Cooling Water Intake Structures• BOP Reliability Testing• Security Regulations (CFATS, TWI• Oil Spill Worst Case Discharge• Idle Iron Issues• API RP 2D Update
• Let the data drive further Agency action

– Significant new regulations have recently been 

effect by both BOEMRE and EPA

• Responsive to the GAO Report findings• Will enhance reporting of facility GHG emiss

– New data should be studied to identify the m

effective means to reduce overall emissions

OOC Recommendation

Comments
• The Agency focus on existing facilities should 

directed at the application of best managemenpractices to reduce overall emissions

– Significant amount of engineering, capital and ti

required to convert facilities to flare

– Added costs could make some fields uneconom

resulting in recoverable reserves being left in th

– Significant number of shelf facilities are satellite

platforms with minimal venting.

– Conversion to flare could actually result in highe

emissions.

OOC Recommendation

Comments
• The Agency should consider establishing a tec

preference forward affecting the design of new facilities, with effective date certain, similar to oregulatory schemes affecting the design of offsfacilities.

OOC Recommendation

Comments
OCS Facilities Vary a Grea

Building Blocks
OCS Facilities Have Evolv
OCS Floating Facilities Va
Floating or Fixed
Vent Vs Flare

Current State

•GOM Facilities utilize both cold venting and flaring operations-specific to design premise for the facility

– Mature shelf facilities utilize cold venting in mo– DW facilities are utilizing flaring to a greater ex

driven by reservoir and production rates.

•Both systems are in place today and are being utiliOCS, within the limits of design.•Drivers for system choices vary and include operatmaintenance, safety and reliability considerations.•Flaring will not eliminate all venting 
Vent Vs Flare: 

Source of Most Emissi

• Data from an OCS platform study indicates majGHG emissions results from

– 85-95% from combustion: power generation

pumping, gas compression, and possibly heageneration

– 5-15% from lease use, flare, vent & fugitiv

•Typically OCS-GOM platforms utilize both natural or diesel power for generation, gas compression, opumping, heat generation, and other lease uses (flpilot/purge, blanket gas, etc.) 
Vent Vs Flare

Opportunities for Redu

•Typical areas of focus for emission reduction coinclude:

– Utilizing More Energy Efficient Combustion Equipm– Utilizing Produced (Own) Gas for Power & Optimiz

Generation (Load Sharing/Shedding) & Compress

– Utilizing & Optimizing Waste Heat for Process– Utilizing Vapor Recovery to Capture Otherwise Ve

Natural Gas

– Eliminating Continuous Venting and Flaring

– Improving Equipment & Production Reliability and 

Failures to Reduce Intermittent Flaring & Venting 

– Implementing a Leak Detection and Repair (LDAR
Vent Vs Flare

BOEMRE Regulations

BOEMRE Regulations Currently In Place to AEmissions•May 2010 - 30 CFR250.1163 effective date Nov 28, 2010

– Flare/Vent meters on all location processing more th

BOPD

– You must report the amount of gas flared and the am

gas vented separately

•October 2010 - NTL 2010-N10 issued 

– Further clarification to 30CFR250.1163 (a)
Vent Vs Flare

OOC recommendations • Prior to taking decisive actions involving new 

regulations OOC recommends the agency alloregulations and guidance’s currently in place tdetermine the most prudent path forward 

– Current regulations and guidance should pr

more reliable data with respect to both:

• Flaring vs. venting &• Recoverable volumes
Vent Vs Flare

What drives the Process Decision?Where is it not practical to flare as opposed to v•Cases that require replacement of existing vent boom becaus

insufficient length due to heat radiation criteria per API 521.•Existing platform is not suitable for replacement/addition of a 

boom/tower due to structural design limitations. Addition of sejacket structure would not be practical.•Cost impact of converting vent to flare could make it unecono

continue to produce, hence leaving production/reserves behin•Production reliability could be impacted due to increased com

maintenance requirements of flare systems as opposed to ven
Vent Vs Flare

• Pilot and purge gas for flare systems will increase lease use 

requirements and may require gas "buy back" to meet the deresult in net increase of GHG’s.

– Gas transmission companies are reluctant to provide this 

producers .

– Impractical for low GOR oil production where excess leas

may not be available due to gas lift requirements.

• Some platforms may require redesign of control systems, ve

i.e. headers and scrubbers, in order to accommodate flaring

– Converting from vent to flare is not as simple as merely a

tip to a vent boom
Flaring May Result in High

GHG Than Venting At Low Emission Facilities

• Smaller throughput facilities with minimal process ventin

1-7 MSCFD) may increase GHG emissions if flaring is rdue to pilot and purge gas requirements

• Assume flare requires 5-30 MSCFD natural gas for pilot 

operation

– At 5 MSCFD pilot + purge gas

• Venting 1 MSCF = 0.35 tonnes CO2e

• Flaring 6 MSCF (1 + 5) = 0.41 tonnes CO2e

– At 16.5 MSCFD pilot + purge gas

• Venting 4 MSCF = 1.40 tonnes CO2e• Flaring 20.5 MSCF = 1.41 tonnes CO2e

(C
Flaring May Result in High

GHG Than Venting At Low Emission Facilities

– At 30 MSCFD pilot + purge gas

• Venting 7 MSCF = 2.45 tonnes CO2e

• Flaring 37 MSCF (7 + 30) = 2.53 tonnes CO2e

– Utilize flaring GHG emissions calculations provided b

98.233(n)

– Assume natural gas composition of approximately 84

and 3% CO2

– Assume flare efficiency = 98%– Changing gas compositions, flare efficiency and met

and pilot/purge needs can significantly impact these calculations. 

(Continued)
Vent Vs Flare

Shelf vs. Deepwater: Considerations for Shelf Platform• Shelf platforms are typically less complex than deep wa

and the vast majorities are unmanned. 

– A significant number of OCSG facilities are satellite/wellhead type 

no capability to vent or flare.

• Vent systems are simpler in design than flare systems; 

ideally suited for most shelf platforms.

• Advantages of venting over flaring

– Does not always require large boom, e.g. emergency vent system

gas facilities.

– Simplest versions (emergency relief) are long piece of open-ende

purge, pilot, ignition or snuffing requirements

– Less expensive in CAPEX and OPEX– Inherently more reliable and less maintenance requirements 
Vent Vs Flare

Considerations Continued...

– Ideal for unmanned/satellite platforms– Practical for open atmospheric systems where inbrea

concern(i.e. no gas blanketing)

– Pilot & purge gas not required

• Advantages of flaring over venting 

– Flaring required on facilities that produce H2S– Better suited to disposing of large volumes of gas to 

vapor cloud formation and uncontrolled ignition

– Typically reduces GHG emissions on facilities that m

release large volumes of gas

– Poses less of a potential hazard to aviation activities 

facilities 
Vent Vs Flare

Considerations in Vent to Flare ConverDesigns•Engineering

– Flare System Design

• Develop technical specifications for flare system 

and instrumentation

– Relief System Study

• Review backpressure effects of flare tip on all as

relief devices

• Confirm vent scrubber sizing for use as flare scru• Review purge gas systems to prevent flashback• Establish thrust loads if applicable 
Vent Vs Flare

• Engineering (continued)

– Radiant Heat Study

• Review effects of personnel exposure to continuo

peak radiant heat levels

– Civil/Structural Review

• Review structural loading on boom and deck with 

of flare equipment

• Review associated risks to helicopters and boats• Review administrative controls to limit access to 

areas and to ensure escape paths 
Vent Vs Flare

• Structural

– Modify or replace boom as necessary

• Boom may need to be modified due to radiant heat or 

loading requirements 

• Facilities

– Install purge and pilot gas source

• Piping and instrumentation required for purge and pilo

from facility fuel gas source

– Install ignition source

• Electrical supply required for ignition source from facili

source

• Wiring for ignition failure alarm recommended for facili

panel
Vent Vs Flare

• Facilities (Continued)

– Install flare tip

• Installation may require lift boat, derrick barge, or 

as necessary

• Install flare control panel on deck location

– Modify relief system as required by findings 

System Study which may include:

• Relief devices • Relief headers • Modify or replace scrubber• Modify or replace boom or tower 
Vent Vs Flare

Schedule• Flare system analysis, design, procurement, 

installation will be a lengthy project 

• Facility downtime will inherently add to the 

complexity and cost of the retrofit
Flare Boom Design Issu

• Flare Booms must be equipped with a 

tip that is appropriate for burning gas. Existing vent tips are not designed for burning gas and will need to be replaced

• If existing Vent Boom does not meet 

the following requirements it will need to be replaced.

‒ Boom must be long enough to minimize 

flare heat exposure to personnel per API Standard 521.

‒ Boom should have walkway to tip to 

allow for maintenance of the flare ignition equipment

Boom

Walkway
Vent Vs Flare

• Replacing the boom will require significa

structural modifications. 

– Older platforms may not be able to support 

appropriately sized flare boom.

– New Structure with bridge back to original p

may be needed to support larger boom.

• Flare Boom will need to be retrofitted w

gas and ignition systems.

• Flares will require a purge gas system t

prevent explosive mixtures from propaginto flare piping. 
Flare Boom Installa

Issues

• Flare tips and Flare Booms cannot be installed wit

cranes

– Lift Boat Needed in Shallow Water (< 150’ Wate– Derrick Barge Needed in Deeper Water– GHG emissions from Installation and Fabricatio

should be considered when assessing overall G

• 4 to7 Days of Facility Downtime Required to Repla• 7 to 14 Days of Facility Downtime Required to Rep

Tie-in Entire Flare Boom
Vent to Flare Conversion 

Cost Study on OCS Platfo

The capital burden associated with converting vents to flares may not be jusexisting production rates in some fields. Operators may choose to abandon leaving otherwise producible reserves in the ground. (Information supplied 

Facility Type

Number of

Facilities

Average Cost

to Convert to

Flare

Total Cost to

Convert to

Flare

Shut‐In

Hydrocarbon

Revenue to

Convert To

Flare

Average

Annual Vent

Volume Per

Facility (MSCF)

Annual CO2

Equivalent of

Vented Gas

(Metric Tons)

Annual CO2

Equivalent of

Flared Gas

(Metric Tons)

Gas Already Flared 6 N/A N/A N/A N/A N/A N/A Satellite Facilities with No

Significant Venting 366 N/A N/A N/A N/A N/A N/A Venting Facilities with

Adequate Vent Boom 28 $ 1,629,000 $ 45,612,000 $ 44,444,444 17,117 223,343 32,111 

Venting Facilities with

Inadequate Vent Boom But

Structure Can Support

Longer Boom 30 $ 2,639,000 $ 79,170,000 $ 47,619,048 4,844 67,719 9,736 

Venting Facilities with

Inadequate Vent Boom ‐

Structure Cannot Support

Longer Boom 5 $ 6,664,000 $ 33,320,000 $ 7,936,508 17,569 40,936 5,886 Totals 435 $ 158,102,000 $ 100,000,000 331,998 47,734 
Vent to Flare Conversi

Schedule For Cost Stu

Year 12345

Quarter 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 

EngineeringProcurementPermittingInstallation
Vent to Flare Convers

Cost Study OCS Facili

Scenario

Number of 

Facilities

Average 

Conversion 

Cost per 

Facility

Total 

Conversion 

Cost

Annual 

Vent 

Volume 

MCF

Annual 

CO2e of 

Vented 

Gas 

(tonnes)

Annual 

CO2e of 

Flared 

Gas

(tonnes)

R

(

Convert all venting facilities to flare. Facility has adequate vent boom or is structurally capable of supporting longer one.

156 $2.0 MM $312 MM 1,551,300 563,800 103,900 4

Capital cost of $312 million to reduce emissions by <0.5 million tonnes CO2e cannot 

economically justified. No payback mechanism for converting vents to flares with no 

(Information supplied by Apache)
Vent to Flare Convers

Schedule OCS Facilitie

Year 123456

Quarter 12341234123412341234123

EngineeringPermittingProcurementInstallation

NOTE: Schedule based on performing engineering on approximately 30 plat
Gas that Cannot be Ro

to Header and Must be Vented Locally

• Atmospheric Tank Vents 

(oil storage and water treating)

• Instrumentation Bleeds• Engine Fuel Gas Blow Down Valves• Compressor Packing / Seal Vents• Relief Valves and Blow Down Valves th

would cause excessive back pressure in Header
OOC Recommendation

Comments

• Let data collected as a result of new BOEM an

emission monitoring regulations drive OCS GHpolicy.

– New regulations in place affecting GHG reporting

• Existing facilities should be allowed to continue 

gas

– Significant amount of engineering, capital and time r

convert facilities to flare

– Added costs make some fields uneconomic resulting 

otherwise recoverable reserves being left in the grou

• Significant number of shelf facilities are 

satellite/wellhead platforms with minimal ventin

– Conversion to flare could result in higher GHG emiss
OOC Recommendation

Comments

• Reductions should be sought through th

application of BMP practices

• BOEMRE stated technology preference 

be appropriate for future facilities 
Vent Vs Flare

Some final thoughts:•With improved emissions monitoring and reportithrough BOEM and EPA regulations, we will havidea of where the most value is in reducing and eliminating GHG emissions, and where to focus regulations and industry guidelines with improvemprojects.