2011 Laurance Reid Gas Conditioning Conference

Transcription

1 ROTARY-VALVE, FAST-CYCLE, PRESSURE-SWING ADSORPTION TECHNOLOGY ALLOWS WEST COAST PLATFORM TO MEET TIGHT CALIFORNIA SPECIFICATIONS AND RECOVER STRANDED GAS 2011 Laurance Reid Gas Conditioning Conference

2 Platform Gail Owned and operated by Venoco, Inc. Built in 1987 Located approximately 10 miles offshore In 739 feet of water 36 well slots 26 operating Processes 3,500 bpd 18 API Crude Oil

3 Venoco, Inc. Headquarters located in Denver, CO Regional headquarters in Carpinteria, CA Independent oil producer (on NYSE) 98.3 MMbbls reserves As of 12/31/09

4 Introduction Stranded Gas Opportunity on Offshore Platform Located in Santa Barbara Channel 100 miles NW of downtown Los Angeles One of man s early sources of crude oil

5 Associated Gas on Platform Gail Gas Associated with Crude Oil Production Oil is Produced on Platform via Gas Lift/ESP Gas in unsellable Does not meet CA specification for sale Component Platform Gail Produced Associated Gas (mol%) California Sales Gas Specification (mol%) Total Inerts (N 2, CO 2 and O 2 ) 15 < 4.0 Carbon Dioxide (CO 2 ) 13 < 3.0 Methane (CH 4 ) 64 > 88.0 Ethane (C 2 H 6 ) 8 < 6.0 Propanes Plus (C 3 H 8+ ) 13 < 3.0 Butanes Plus (C 4 H 10+ ) 7 < 1.5 Water (H 2 O) Saturated < 7 #/MMcf

6 Gas is Stranded Available Options Flared Out of the question Production Could be Cut to Avoid Making Gas Also out of question Re-injected into Injection Well Expensive Loss of Revenue Compression Costs

7 Previous Gas Flow Diagram Glycol Unit Gas Turbines Associated Gas from Oil-Gas Separators 1 st Stage Compression Vapor Recovery Gas Sweetening 2nd Stage Compression 3rd Stage Compression Gas Lift Production Wells Injection Well Gas from Reservoir is Sour Contains over 4,000 ppm H 2 S Sweetened to < 4ppm 1 MMscfd of Gas is Injected at 2,000 psig Loss Revenue of About $ MM/year

8 Treating to Gas Specification Not Justified Methods Researched Included CO 2 removal by amine Refrigeration to remove light hydrocarbons Lean oil absorption to extract ethane Mole Sieve and Turbo Expansion Dehydration by triethlyene glycol/adsorption Would have Required Combination of Units Insufficient room Too much weight Investigated Both On/Offshore Including neighboring platforms

9 What is Pressure-Swing Adsorption (PSA)? Selectively Removes Compounds from Feed Gas Adsorbing Process Step (elevated pressure) Feed gas flows upward thru bed of adsorbent Targeted compounds remain in the adsorbent bed Lighter, smaller hydrocarbons (CH 4 ) pass thru the bed As time goes by, the bed becomes saturated Regeneration Process Step (lower pressure) Takes place prior to adsorbent bed saturation Pressure is released thru the bottom of adsorbent bed Releases adsorbed compounds as exhaust gas

10 Fast-Cycle, Rotary-Valve PSA Developed From Biogas and CH 4 /H 2 Separation By Xebec, Inc, - of Quebec, Canada Has Benefits of Mole Sieve, and Molecular Gate Much smaller footprint 18 ft(l) X 8 ft(w) X 9 ft(h) Fewer moving parts Much less CapEx Replaces Amine for CO 2 removal LTS/expander for de-riching Glycol unit for dehydration

11 What is a Rotary Valve? Type of Valve in which the Rotation of a Passage(s) in a Transverse Plug Regulates Flow of Liquid or Gas Stopcock is the simplest form Rotary Valves have Many Applications: Brass instruments Two-stroke motorcycle engines Automobile engines Gas chromatography Equalize pressure

12 Rotary Valves on Xebec PSA Unit? Four Valves Replacing more than 24 valves Heavies Valves Control flow at bottom of beds Lights Valves Control flow at top of beds

13 Demonstration Plant Study April 2006 Used Full-Scale M-3100 Unit On 2 nd Stage Inlet Gas (Sweetened) Glycol Unit Gas Turbines Associated Gas from Oil-Gas Separators 1 st Stage Compression Vapor Recovery Gas Sweetening Demonstration Test PSA Xebec M nd Stage Compression 3rd Stage Compression Gas Lift Production Wells Injection Well

14 Demonstration Study Indicates Success! CO 2 Reduction of 84.3% CH 4 Increase of 46.3% C 2 Decrease of 70.63% C 3+ Decrease of 97.54% Component Platform Gail Produced Associated Gas (mol%) California Sales Gas Specification (mol%) Total Inerts (N 2, CO 2 and O 2 ) 3.70 < 4.0 Carbon Dioxide (CO 2 ) 2.03 < 3.0 Methane (CH 4 ) > 88.0 Ethane (C 2 H 6 ) 2.35 < 6.0 Propanes Plus (C 3 H 8+ ) 0.32 < 3.0 Butanes Plus (C 4 H 10+ ) 0.03 < 1.5 Water (H 2 O) - < 7 #/MMcf

15 Commercial Application Started May 2010 Excess Gas is no Longer Pressurized to 2,000 psig Thereby saving energy as well as compressor capacity Sales Quality Gas is now Produced on Platform Negating the need for line pigging No Water Vapor being Sent to the Turbines Resulting in higher turbine efficiencies Processing the PSA Vent Gas Through the Turbine Captures C 2 through C 5 compounds Processing CO 2 from the PSA Lowers the flame temperature in the turbine, thereby negating any potential negative effects from ignition of the heavier hydrocarbons

16 Commercial Application Results More than 2.5 MMscfd (average) Processed Never a shutdown due to sales gas quality Control of Unit As rotary valve speed increases, so does sales gas quality As rotary valve speed increases, product flow decreases Component Platform Gail Produced Associated Gas (mol%) California Sales Gas Specification (mol%) Total Inerts (N 2, CO 2 and O 2 ) 2.61 < 4.0 Carbon Dioxide (CO 2 ) 1.42 < 3.0 Methane (CH 4 ) > 88.0 Ethane (C 2 H 6 ) 2.95 < 6.0 Propanes Plus (C 3 H 8+ ) 1.36 < 3.0 Butanes Plus (C 4 H 10+ ) 0.57 < 1.5 Water (H 2 O) - < 7 #/MMcf

17 Appearance of Commercial Unit

18 Ethane Removal C 2 Removal Greater than Sixty Percent On Platform Gail Proven at other locations as well PXP Murphy Venoco Beverly Hills (Demonstration Unit) C 2 Inlet (mol%) C 2 Outlet (mol%) Removal Laboratory Tests % Demonstration Study % Commercial Unit %

19 Turbine NO X Emissions Indicates that NO X Levels have Decreased From 18 to 69% Other factors not considered Turbine Turbine Exhaust NOx Level (ppm) Five months prior to PSA Start-up Five months after PSA Start-up G G G

20 Questions