FLARE RECOVERY SYSTEMS AND THE “FLARE BULLET”
Economic approach to flare minimisation
Jonathan MILES Argo Environmental Engineering Limited
The Environment
• CO2 from Power Generation and Fuel Gas
• CO2 from Flaring
• VOC from tank emissions / transport
Environmental Emissions - UKOOA
Flaring rose in UK in 2006 to 1.725 m tonnes
CO2 emissions in 2006 fell by about 1m tonnes
UKOOA Commitment 47
• UK Flaring in 2001 represented about 30% of Industry CO2 emissions (5.5 m tonnes) • Started Emission Trading Scheme • Participants agreed target 10% emission reduction below consent agreements
Best In Class?
• Analysis 2000-2004 has shown:
– Best in class produces 0.63 ave kg CO2/boe Worst in class – 38.61 ave kg – Of worst 10 performers in flaring only 3 had stranded gas reservoirs with 7 connected to gas gathering systems – Foinhaven has stranded gas reservoir but achieves in top 10 CO2 from Flare / boe
• 7 of top 10 performers were BP operated
How does reduced flaring save cost
• The “Death Zone” on a flare – Turndown to 1-2% • Flare and associated equipment damage • Wasted Gas – especially if fuel gas deficient – burning diesel • CO2 or trading or tax regime. • Reputation • Potential revenue/cost saving of $1million per year
What is zero flaring
Flare Gas Recovery
HP flare
Bursting Disc LO
HH HH
To flare LO
PT
PT
FOV N2 supply XV FE
HH
Check valve
Sources
HP K.O. Drum
Drain
FOV Layout
To flare Bursting disc Tie in 2 Tie in 1 FOV
Manual valve
Fast Opening Valve
• Mokveld valve has SIL-level 3
(MTBF=2160 years of operation to "full stroke")
• Tyco valve has SIL-level 3 (MTBF=523
years of operation to "full stroke")
Flare Opening Assemblies Rupture disc/Buckling pin valve
Buckling pin valve Bursting disc
Flare Gas Recovery – economics
• Annual value assuming:
– Quota trading – Increased gas export – 2 flare change outs – Annual revenue from flare gas recovery $1,000,000
• Typical Installed Cost - $2-4 million
(cheaper on new facilities)
• Pay back time will typically be 2-4 years
Low Pressure System
Flare Gas Ignition
•LP ignition system:
– Automatic Pellet Launching cabinet and air launching bottle – Guide pipe – Pellet collector unit (optional)
LP system typical installation
Flare Gas Ignition System
• • • • •
Long-range ignition pellet Armed by the launching pressure Ignite when emerged from guide pipe Independent of emerging velocity Will not ignite if exposed to fire
Low pressure Ignition System
Ekulama II - SPDC Nigeria
Low pressure Ignition System
Ekulama II - SPDC Nigeria
Flare Gas Ignition
• No moveable parts or electronic equipment located near flare tip • When required maintenance is performed at cabinet • All equipment in heat radiation areas are heat in resistant material • High reliability and long lifetime
Conclusions and Recommendations
• Install FGR if technically feasible
– Increased revenue typically $1million – Cost to install $2 – 4 million
• Install Pellet Ignition system – suit all systems
– Increased reliability of ignition – Increased safety – Reduced maintenance cost
– Cost approx $150,000