Tracer technologies to assess and monitor EOR and IOR projects
Transcription
Tracer technologies to assess and monitor EOR and IOR projects
Tracer technologies to assess and monitor EOR and IOR projects Olaf Huseby, Sven Hartvig, Kjersti Jevanord & Øyvind Dugstad Restrack AS, Instituttveien 18, NO-2027, Kjeller Norway Outline • Restrack -‐ tracer service based on Ins2tute for energy technology (IFE) research • Informa2on from tracer data • Field applica2on of the par22oning inter-‐well tracer test • Summary 2 4 mai 2015 IFE legacy 1950ies IFE started work with radioactive tracers, ground water studies 1983 – 86 offshore use of tracers at Ekofisk started 1991 – development for application of chemical tracers 1994 – consecutive frame agreements with Statoil and ConocoPhillips. 1995 – world-wide project expansion 2005 IFE established Resman together with Sintef 2011 – deployment of Single Well Chemical Tracer Test (SWCTT) 2012 – Introducing tracers for partitioning Inter-well Tracer Test (PITT) Inter-well tracer test Producers Injectors Injector • Injec2on water is "colored" by tracers • Water from specific injector iden2fied 4 4 mai 2015 Inter-continental tracer test Injectors Tracer distribution 5 4 mai 2015 Connectivity from tracer data I-‐1 I-‐2 P-‐1 P-‐2 P-‐3 • Sealing / non-‐sealing faults • Topology of the reservoir • Tracers can explain unexpected water breakthrough 6 4 mai 2015 Residence time distribution (RTD) analysis I-‐1 I-‐2 P-‐1 P-‐2 Moments of the distribu2on: 𝑚↓0 =∫0↑∞▒𝐸(𝑡)𝑑𝑡 𝑚↓1 =∫0↑∞▒𝑡∙𝐸(𝑡)𝑑𝑡 7 4 mai 2015 Number of tracers arrived P-‐3 Swept volume: 𝑉↓𝑠 =𝑄↓𝑖 𝑚↓1 / 𝑚↓0 Time Characterize the heterogeneity 80% of water flows in 20% of volume Flow capacity (amount produced) 1 Storage capacity (volume swept 30% of water flows in 20% of volume 0 8 Storage capacity (volume swept) 04.05.15 1 • Heterogeneous flow yields curve far from diagonal • Homogeneous flow yields close to diagonal curve • Area between diagonal and curve gives Lorentz coefficient Heterogeneity from RTD (sandstone) 5.0E-‐4 Ec(t) [1/day] data and extrapolation 4.0E-‐4 fit of data 3.0E-‐4 BOCK 081 2.0E-‐4 1.0E-‐4 0.0E+0 0 200 400 600 800 1000 t [days] 1200 1400 1600 𝑇↓𝑚 =516 𝑑 ⟨𝑇⟩=590 𝑑 𝐿↓𝑐 =0.18 𝑀↓0 =19 % 𝑉↓𝑠 =13000 𝑚↑3 BOCK 081 4.0E-‐3 data and extrapolation fit of data Ec(t) [1/day] 3.0E-‐3 BOCK 056 2.0E-‐3 BOCK 056 1.0E-‐3 0.0E+0 0 9 200 04.05.15 400 600 800 1000 t [days] 1200 1400 1600 𝑇↓𝑚 =478 𝑑 ⟨𝑇⟩=637 𝑑 𝐿↓𝑐 =0.15 𝑀↓0 =86 % 𝑉↓𝑠 =66000 𝑚↑3 Heterogeneity from RTD (carbonate) 1.0 Well P-‐A Well P-‐B 0.8 0.6 F 𝑇↓𝑏 =54 d P-‐B ⟨𝑇⟩=414 𝑑 𝐿↓𝑐 =0.46 𝑀↓0 =0.14 % 𝑉↓𝑠 =680 𝑚↑3 BO-81 (sandstone 0.4 0.2 0.0 0.0 0.2 5.0E-‐5 I-‐1 10 04.05.15 Φφ 0.6 0.8 1.0 5.0E-‐6 Well P-‐A 4.0E-‐5 4.0E-‐6 Well P-‐B Ec(t) [1/day] 𝑇↓𝑏 =82 d ⟨𝑇⟩=802 𝑑 P-‐A 𝐿↓𝑐 =0.32 𝑀↓0 =3.3 % 𝑉↓𝑠 =35500 0.4 3.0E-‐5 3.0E-‐6 2.0E-‐5 2.0E-‐6 1.0E-‐5 1.0E-‐6 0.0E+0 0 500 1000 t [days] 1500 0.0E+0 2000 Oil saturation from tracer data par44oning tracer ordinary water tracer I-‐1 I-‐2 P-‐1 P-‐2 Satura4on given from 𝑺↓𝒐 =𝒕↓𝒑 −𝒕↓𝒘 /𝒕↓𝒑 +𝒕↓𝒘 (𝑲−𝟏) 11 4 mai 2015 P-‐3 SWCTT - principle Ester (partitioning tracer) is injected in watered-out zone (1 day) Ester partly hydrolyses to alcohol during shut-in (2-3 days) Field data yields Sor=0.21. (Data from ENI operated West African onshore field, IPTC paper 17951 for details) Ester and secondary tracer is produced (2 days) 12 04.05.15 PITT - principle Partitioning tracer (red) is delayed if oil is present Partitioning tracer time delay gives amount of oil present Concentration [ppm] Partitioning tracer (red) and water tracer is co-injected Partitioning Non-‐partitioning 200 100 0 0 20 40 Time [days] 60 80 PITT vs SWCTT SWCTT: • close to the well • extensive operation, 1-2 week • test in producer • interrupt production • immediate results PITT: • well to well test • simple injection operation, 1-2 days • injector well, no production interrupts • results after tracer breakthrough Wellbore Partitioning inter-well tracer testzone Typical SWCTT zone 4m 500 m Recap of IFE research to find suitable partitioning tracers • Several tracers have been used for non-‐aquous phase liquid (NAPL) remedia2on • For oil field applica2ons: problem finding tracers that survive reservoir temperature and biodegrada2on • Breakthrough: PITT tracers iden2fied and tested by Viig et al. (SPE164059) 15 04.05.15 Exampel of tracer that biodegraded (Dugstad et al., 2013) Field application, Total operated Lagrave field 1km LAV-‐2 LAV-‐6 LAV-‐1 LAV-‐7 (injector) Lagrave reservoir characteristics: • Thickness 10-‐30 m • Porosity 13-‐20 % • Permeability 10-‐50 mD 16 4 mai 2015 • Used to field test new PITT tracers (Viig et al. 2013, SPE 164059) • Carbonate field with large water produc2on ~ 95% water cut • Short well distances • Water cycled • Residual satura2on also known from cores ~ 25% Saturation from PITT in Lagrave 2.5E-‐3 Non-‐partitioning Partitioning 2.0E-‐3 E(t) 1.5E-‐3 From cores: So=25-28 %, i.e. compares well to PITT results 1.0E-‐3 5.0E-‐4 0.0E+0 0 17 4 mai 2015 200 400 600 800 Days after injection 1 000 1 200 Data from Viig et al. (SPE164059) PITT in the Bockstedt Schizophyllan biopolymer pilot1 • mature (60+ years) oilfield located about 50 km from Bremen • poorly consolidated sandstone, mid to coarse grained, well-sorted and fairly homogeneous • reservoir temperature about 54°C • f o r m a t i o n w a t e r : s a l i n e b r i n e (186,000ppm TDS). 250 m • test area is water-flooded (high water cut) with one injector and three producers. Produced water is reinjected 1) For detailes: Leonhardt, B. et al. SPE 169032. SPE 2014 IOR Symp Ogezi, O., et al. SPE 169158. SPE 2014 IOR Symp Leonhardt, B., et al. (2013) Paper A10 17th EAGE European IOR Symp. Leonhardt, B., et.al (2011) Paper B05 16th EAGE European IOR Symp. Preliminary PITT results BO-56 4.0E-‐3 2-‐FBA Ec(t) [1/day] 3.0E-‐3 2-‐FBOH 𝑆↓𝑜 =𝑇↓𝑝 −𝑇↓𝑤 /𝑇↓𝑝 +𝑇↓𝑤 (𝐾 −1) = 801−478/801+478(3.6−1) =0.16 2.0E-‐3 1.0E-‐3 0.0E+0 0 19 04.05.15 500 1000 t [days] 1500 2000 Summary, tracers for IOR/EOR 20 Technology Benefit Conventional tracers & RTD Identify targets for IOR • Communication • Sweep SWCTT Assess efficiency of EOR chemicals & protocols • Reduction in Sor PITT Identify targets for EOR Assess EOR efficiency on inter-well scale 4 mai 2015 Acknowledgements Thanks to IFE and all partners in previous and current tracer JIPs: Statoil, ConocoPhillips, Wintershall, ENI, Total, RWE, Lundin, Saudi Aramco, GDF Suez BACKUPSLIDES 22 4 mai 2015 Partitioning vs. non-partitioning 𝑆↓𝑜 =𝑇↓𝑝 −𝑇↓𝑤 /𝑇↓𝑝 +𝑇↓𝑤 (𝐾−1) = 787−516/787+516(3.6−1) =0.13 5.0E-‐4 BOCK 081 4.0E-‐4 2-‐FBA Ec(t) [1/day] 2-‐FBOH 3.0E-‐4 2.0E-‐4 1.0E-‐4 0.0E+0 0 500 4.0E-‐3 1000 t [days] 1500 BOCK 056 2-‐FBA 3.0E-‐3 Ec(t) [1/day] 2000 2-‐FBOH 2.0E-‐3 1.0E-‐3 0.0E+0 0 23 𝑆↓𝑜 =𝑇↓𝑝 −𝑇↓𝑤 /𝑇↓𝑝 +𝑇↓𝑤 (𝐾−1) = 801−478/801+478(3.6−1) =0.16 04.05.15 500 1000 t [days] 1500 2000 Travel 2mes used in So es2mates corresponds to mode of RTD. Mean 2mes are more fragile as the full tail of the par22oning tracer curves are s2ll not available. Moving oil for BO-81 120 100 Bo-‐56 Bo-‐81 Water cut [%] 80 BOCK 081 Mobile oil 60 40 20 0 01.06.2012 BOCK 056 30.11.2012 01.06.2013 30.11.2013 01.06.2014 01.12.2014 Effect of moving oil Moving oil gives a smaller Tp 𝑆↓𝑜 =𝑇↓𝑝 −𝑇↓𝑤 /𝑇↓𝑝 +𝑇↓𝑤 (𝐾−1) 𝑆↓𝑜↑′ ={𝑇↓𝑝 +∆↓𝑇 }−𝑇↓𝑤 /{𝑇↓𝑝 +∆↓𝑇 }+𝑇↓𝑤 (𝐾−1) By trial and error we can find a ∆↓𝑇 that gives 𝑆↓𝑜 corresponding to that for BOCK-‐56: 𝑆↓𝑜↑′ =(787+80)−516/ (787+80)+516(3.6−1) =0.16 Ultra sensitive tracer analysis 1800 m GC-MS 560 m Illustration of investigation area for Noise TQF = 1E6 m3 (corresponding to limit of detection of 5 ppb) and TQF = 1E8 m3 (corresponding to limit of detection of 50 ppt) and the same amount of tracer injected Noise Tracer signal GC-MS In example: 400 parts per trillion tracer in produced water sample Tracer signal GC-MS/MS Tracer signal Tracer signal In example: 400 parts per trillion tracer in produced Detection limitwater has significant impact on required sample tracer injection mass. If 50 kg is needed to GC-MS/MS investigate a field at 50 ppt, 5000 kg is needed for the same investigation at 5 ppb 04.05.15