Dual Gas Lift Well Analysis Using WellTracer

Transcription

1 33 rd Gas-Lift Workshop Houston, Texas, USA February 1-5, 2010 Dual Gas Lift Well Analysis Using WellTracer Tony Hord ExxonMobil Production Company This presentation is the property of the author(s) and his/her/their company(ies). It may not be used for any purpose other than viewing by Workshop attendees without the expressed written permission of the author(s).

2 Corporate Separateness Exxon Mobil Corporation has numerous subsidiaries, many with names that include ExxonMobil, Exxon, Esso and Mobil. For convenience and simplicity in this presentation, the parent company and its subsidiaries may be referenced separately or collectively as "ExxonMobil." Abbreviated references describing global or regional operational organizations and global or regional business lines are also sometimes used for convenience and simplicity. Nothing in this presentation is intended to override the corporate separateness of these separate legal entities. Working relationships discussed in this presentation do not necessarily represent a reporting connection, but may reflect a functional guidance, stewardship, or service relationship.

3 Dual Gas Lift Well Analysis Using WellTracer WellTracer / WinGLUE Tools Dual Well Operations WellTracer Technology Advantages Results of Surveys Plans Feb. 1-5, Gas-Lift Workshop 3

4 WellTracer What is WellTracer? Patented technology that traces the path of injected CO2 in a producing well. Noninvasive method to determine downhole conditions leaving well flow undisturbed. How Does WellTracer Work? Man-portable Requires temporary connection points on the gas injection line and the production line. CO2 is injected in the annulus and sensed when it returns on the production line Well data including tubular design, gas lift valve setting depths, gas lift injection and production rates are input to WinGLUE (Appsmiths) software along with WellTracer data to establish lift point, possible leaks from casing to tubing, and multi-point injection.

5 WellTracer Why the Technology is Needed Communication Casing / Tubing Combination of wireline methods used in most cases to pin point source of communication, requires wellbore intervention WellTracer identifies source of communication without wellbore intervention No loss of Production or downtime from conventional troubleshooting tools Pony Tail Hole Finder Caliper Survey WellTracer 3 Days 3 Days 6 Days 1 Day FIELD South Timbalier Block 54 LEASE OCS-G 020 WELL B-33/33D ENGINEER Tony W. Hord INITIAL DATE July 21, 2008 WELL STATUS DRAWING STATUS Gas Lift Valve Installation Current Sketch DRAWING BY Lester Matthews, Jr. ZERO RKB-MWL WD KOP MAX DEV D&C o NIPPLES # TYPE DEPTH ID SS 1 SCSSV SS 2 HWS SS 3 SWN LS 1 SCSSV LS 2 SWS TUBING STR OD ID WT GR TH FRM TO CASINGS OD GR WT DEPTH 18-5/ / /8 P /8 Q P WELL HEAD Halliburton Wellstar +/ ft MD (ID=2.188 ) Long String: TK-7 IPC 2-7/8, 7.9-ppf, P-110 BTS-6 to 2596-ft MD 2-7/8, 6.5-ppf, P-110 BTS-8 to ft MD 2-3/8, 4.7-ppf, P-105 BTS-8 to ft MD GASLIFT MANDRELS MD Long String 1690 Dummy 3263 Dummy 4849 Press. Valve 6282 Dummy 7527 Dummy 8742 Dummy 9925 Dummy 7-5/8, 47.1 ppf, +/ ft MD / ft TVD 2-7/8 HWS +/ ft MD (2.188 ID) 2-3/8 SWS +/ ft MD (ID=1.875 ) GT dual +/ ft MD 4, 11.6 ppf Blank Pipe ft MD SlimPak 140,.006 ga, screen ft MD, 20/40 gravel pack sand Sump +/ ft MD #1 # ppg CaCl 2 packer fluid +/- 991-ft MD / 991-ft TVD Halliburton Well star +/ ft MD (ID=2.188 ) Short String: TK-7 IPC 2-7/8, 7.9-ppf, P-110 BTS-6 to 2594-ft MD 2-7/8, 6.5-ppf, P-110 BTS-8 to ft MD 2-3/8, 4.7-ppf, P-105 BTS-8 to ft MD +/ ft MD / 5987-ft TVD GASLIFT MANDRELS MD Short String 1657 Press. Valve 3199 Press. Valve 4784 Press. Valve 6218 Dummy 7464 Dummy 8680 Dummy 9864 Dummy 9-7/8, / ft MD 2-7/8 HWS +/ ft MD (ID = ) 2-3/8 CMD Sliding Sleeve@ +/ ft MD (ID=1.995 ) 2-3/8 SWN +/ ft MD (ID = ) GP +/ ft MD H ft MD / ft TVD 5 +/ ft / ft TVD +/ ft / ft TVD Cost of WellTracer survey is ~27% of conventional troubleshooting methods not counting production downtime. DRAWING LEGEND cement open perforations gravel pack sand Halliburton Crimson Vent Screen PBTD +/ ft MD ft TVD RA +/ ft MD H ft MD / ft TVD 5 +/ ft MD / ft TVD

6 WellTracer Why the Technology is Needed Dual well operation is difficult to optimize with complex gas lift designs and common annulus Inability to control injection rate & pressure per string Producing various fluid gradients into the production system Valve type & setting are critical for a successful & efficient operation

7 Tools for well diagnostics WellTracer / WinGLUE software, identifies / validates gas lift through put rate per valve Echometer acoustic well sounding equipment / software & pressure transducers validate gas pressure per valve Clamp on gas meter is used to measure input gas lift rate to the well(s)

8 First industry wide dual WellTracer survey ExxonMobil obtained two WellTracer analyzers in May 2009 and performed the first dual well survey at ST-54 B33 (Long string)/b33d(short string) One string equipped with IPO and the other with PPO unloading valves. Both wells showed loading tendencies May 2007 Unsuccessful at gas lifting both strings effectively through Sep 2008 May 2009 RE, SSE, AL, Ops collected historical data to calibrate WinGLUE model to determine WellTracer predictions, predict survey time and coordinate offshore logistics. June 2009 Gas Lift Team performed WellTracer on both strings GL Techs working with Operations set wells up for simultaneous tracer surveys Surveyed - B33 day 1, B33D day 2, B33/B33D day 3 (2 WellTracer analyzers used 3 rd day) WellTracer surveys results reviewed by GL Techs, AppSmiths, and Gas Lift Consultant WinGLUE modeling estimated both wells capable of a combined rate of 292 BOPD Recommendation made to decrease orifice valve from 10/64 to 8/64 in the B33 and increase gas lift injection pressure (casing) by 30 psi July 26, 2009 Field Operations installed recommendation July 27-29, 2009 GLT unloaded wells and returned to production August 3, 2009 both wells producing better than prediction at 317 BOPD combined rate with both strings in stable flow.

9 First Industry Wide Dual WellTracer Survey Well data was collected, using FPT, Well Tests and Echometer data. This information was input into WinGLUE to create a PREDICTIVE MODEL prior to performing a WellTracer analysis. Pressure (psig) Vertical Depth (feet) Depth vs Pressure Well: [GLUE] SOUTH TIMBERLIER,54,B33,SS 10-Jun :10:47 Production Pressure Model: MMSM Injection Pressure Model Avg. Flowing Pressure Survey Open / Closing Points (Open) Open / Clos Mandrel 1 (

10 First Industry Wide Dual WellTracer Survey Once WellTracer Analysis was performed, the actual data was matched with the predictive data and we were able to make a specific recommendation Concentration (%) :00:00 1:06:40 2:13:20 3:20:00 4:26:40 5:33:20 6:40:00 7:46:40 8:53:20 Time (hh:mm:ss) Concentration Vs. Time Well: [GLUE] SOUTH TIMBERLIER,54,B33,LS 22-Jun :00:20 Total Transit 1 (1690 MD - Dummy - Dummi Total Transit 2 (3263 MD - Dummy - Dummi Total Transit 3 (4849 MD - Macco R-1D 5/ Total Transit 6 (8742 MD - Dummy - Dummi Total Transit 7 (9925 MD - Dummy - Dummi Raw CO2 Concentrations Total Transit 4 (6282 MD - Dummy - Dummi Total Transit 5 (7527 MD - Dummy - Dummi

11 USP WellTracer Survey Activities 237 BOPD uplift achieved 410 BOPD uplift identified 18 WellTracer surveys conducted to date August 2008 Weatherford performed survey at GI 16 W-31 Well Findings revealed leaking top mandrel, recommended replacing top valve, predicted possible 60 BOPD BU (100 fill top of perfs) May 2009 West Texas 6 Pegasus Gas Lift Wells First surveys run with Company owned equipment Recommendation follow up resulted in 72 BOPD BU Potential 141 BOPD BU remaining if recommendations implemented and achieved June 2009 ST 54 B33/B33D - 2 Wells / 4 surveys (First Dual Survey) 137 BOPD BU July 2009 GI 16 L-8, T-38ST, T-51, U-50-4 Wells Possible 210 BOPD BU remaining if recommendations implemented and achieved July 2009 Hoover/Dianna HA-5 attempted 2 WT surveys to identify surging issues Based on finding were able to recommend reducing gas injection rate by 1.5 MCFD and lowering gas injection pressure to 1474 psi (the operating pressure of 1585 psi was causing surging and multi-pointing August 2009 Gal 209 B8D Attempted to run survey on future TP&A well to determine possible communication but not able to establish injection rate

12 WellTracer Future Plans Current WellTracer equipped team is comprised of two Field gas Lift Technicians, two Engineer technicians and one Analyst GOM ~75 SI Wells (+40 duals) Most duals (one string) SI since 2005 Hurricane Katrina Couldn t unload after being SI for repairs GOM Ongoing communication checks, Trouble shooting &optimization Offshore California, SYU Gas lift orifices may be oversized WellTracer Surveys ~75 wells Acquisition of Auxiliary Equipment WellTracer Units, Transportation, Storage, Gas Bottles, Self Contained Unit, RAMBO Computers, Wireless Transducers, Additional Training Global Implementation for Gas Lift Optimization with an added fully equipped, traveling Gas Lift Optimization team. UK North Sea Equatorial Guinea Australia Malaysia (large number of dual wells) Nigeria (some dual wells) Newfoundland

13 Thanks! Use of referenced equipment and software in this presentation is with the permission of: WellTracer is patented and distributed by Appsmiths, Houston, Texas, WinGLUE software is distributed by Appsmiths, Houston, Texas, com Echometer well sounding equipment and Echometer software are distributed by Echometer Company, Wichita Falls, Texas, Feb. 1-5, Gas-Lift Workshop 13

14 Copyright Rights to this presentation are owned by the company(ies) and/or author(s) listed on the title page. By submitting this presentation to the Gas-Lift Workshop, they grant to the Workshop, the Artificial Lift Research and Development Council (ALRDC), and the American Society of Mechanical Engineers (ASME), rights to: Display the presentation at the Workshop. Place it on the web site, with access to the site to be as directed by the Workshop Steering Committee. Place it on a CD for distribution and/or sale as directed by the Workshop Steering Committee. Other uses of this presentation are prohibited without the expressed written permission of the company(ies) and/or author(s) who own it and the Workshop Steering Committee. Feb. 1-5, Gas-Lift Workshop 14

15 Disclaimer The following disclaimer shall be included as the last page of a Technical Presentation or Continuing Education Course. A similar disclaimer is included on the front page of the Gas-Lift Workshop Web Site. The Artificial Lift Research and Development Council and its officers and trustees, and the Gas-Lift Workshop Steering Committee members, and their supporting organizations and companies (here-inafter referred to as the Sponsoring Organizations), and the author(s) of this Technical Presentation or Continuing Education Training Course and their company(ies), provide this presentation and/or training material at the Gas-Lift Workshop "as is" without any warranty of any kind, express or implied, as to the accuracy of the information or the products or services referred to by any presenter (in so far as such warranties may be excluded under any relevant law) and these members and their companies will not be liable for unlawful actions and any losses or damage that may result from use of any presentation as a consequence of any inaccuracies in, or any omission from, the information which therein may be contained. The views, opinions, and conclusions expressed in these presentations and/or training materials are those of the author and not necessarily those of the Sponsoring Organizations. The author is solely responsible for the content of the materials. The Sponsoring Organizations cannot and do not warrant the accuracy of these documents beyond the source documents, although we do make every attempt to work from authoritative sources. The Sponsoring Organizations provide these presentations and/or training materials as a service. The Sponsoring Organizations make no representations or warranties, express or implied, with respect to the presentations and/or training materials, or any part thereof, including any warrantees of title, noninfringement of copyright or patent rights of others, merchantability, or fitness or suitability for any purpose. Feb. 1-5, Gas-Lift Workshop 15