Wettability Alteration to Intermediate Gas-Wetting in Gas-Condensate Reservoirs at High Temperatures
- Mashhad Mousa Fahes (Imperial College) | Abbas Firoozabadi (Reservoir Engr. Research Inst.)
- Document ID
- Society of Petroleum Engineers
- SPE Journal
- Publication Date
- December 2007
- Document Type
- Journal Paper
- 397 - 407
- 2007. Society of Petroleum Engineers
- 5.8.8 Gas-condensate reservoirs, 4.1.2 Separation and Treating, 5.2.1 Phase Behavior and PVT Measurements, 2.2.2 Perforating, 5.4.7 Chemical Flooding Methods (e.g., Polymer, Solvent, Nitrogen, Immiscible CO2, Surfactant, Vapex), 1.8 Formation Damage, 3.2.3 Hydraulic Fracturing Design, Implementation and Optimisation, 1.6.9 Coring, Fishing
- 1 in the last 30 days
- 1,174 since 2007
- Show more detail
- View rights & permissions
|SPE Member Price:||USD 10.00|
|SPE Non-Member Price:||USD 30.00|
Wettability of two types of sandstone cores, Berea (permeability on the order of 600 md), and a reservoir rock (permeability on the order of 10 md), is altered from liquid-wetting to intermediate gas-wetting at a high temperature of 140C. Previous work on wettability alteration to intermediate gas-wetting has been limited to 90C. In this work, chemicals previously used at 90C for wettability alteration are found to be ineffective at 140C. New chemicals are used which alter wettability at high temperatures. The results show that: (1) wettability could be permanently altered from liquid-wetting to intermediate gas-wetting at high reservoir temperatures, (2) wettability alteration has a substantial effect on increasing liquid mobility at reservoir conditions, (3) wettability alteration results in improved gas productivity, and (4) wettability alteration does not have a measurable effect on the absolute permeability of the rock for some chemicals. We also find the reservoir rock, unlike Berea, is not strongly water-wet in the gas/water/rock system.
A sharp reduction in gas well deliverability is often observed in many low-permeability gas-condensate reservoirs even at very high reservoir pressure. The decrease in well deliverability is attributed to condensate accumulation (Hinchman and Barree 1985; Afidick et al. 1994) and water blocking (Engineer 1985; Cimolai et al. 1983). As the pressure drops below the dewpoint, liquid accumulates around the wellbore in high saturations, reducing gas relative permeability (Barnum et al. 1995; El-Banbi et al. 2000); the result is a decrease in the gas production rate.
Several techniques have been used to increase gas well deliverability after the initial decline. Hydraulic fracturing is used to increase absolute permeability (Haimson and Fairhurst 1969). Solvent injection is implemented in order to remove the accumulated liquid (Al-Anazi et al. 2005). Gas deliverability often increases after the reduction of the condensate saturation around the wellbore. In a successful methanol treatment in Hatter's Pond field in Alabama (Al-Anazi et al. 2005), after the initial decline in well deliverability by a factor of three to five owing to condensate blocking, gas deliverability increased by a factor of two after the removal of water and condensate liquids from the near-wellbore region. The increased rates were, however, sustained for a period of 4 months only. The approach is not a permanent solution to the problem, because the condensate bank will form again. On the other hand, when hydraulic fracturing is used by injecting aqueous fluids, the cleanup of water accumulation from the formation after fracturing is essential to obtain an increased productivity. Water is removed in two phases: immiscible displacement by gas, followed by vaporization by the expanding gas flow (Mahadevan and Sharma 2003). Because of the low permeability and the wettability characteristics, it may take a long time to perform the cleanup; in some cases, as little as 10 to 15% of the water load could be recovered (Mahadevan and Sharma 2003; Penny et al. 1983). Even when the problem of water blocking is not significant, the accumulation of condensate around the fracture face when the pressure falls below dewpoint pressure could result in a reduction in the gas production rate (Economides et al. 1989; Sognesand 1991; Baig et al. 2005).
|File Size||2 MB||Number of Pages||11|
Afidick, D., Kaczorowski, N.J., and Bette, S. 1994. Production Performance of aRetrograde Gas Reservoir: A Case Study of the Arun Field. Paper SPE 28749presented to the SPE Asia Pacific Oil and Gas Conference, Melbourne, 7-10November. DOI: 10.2118/28749-MS.
Al-Anazi, H.A., Walker, J.G., Pope, G.A., Sharma, M.M., and Hackney, D.F.2005. A Successful MethanolTreatment in a Gas/Condensate Reservoir: Field Application. SPEPF20 (1): 60-69. SPE-80901-PA. DOI: 10.2118/80901-PA.
Anderson, W.G. 1987a. Wettability Literature Survey—Part 5:The Effects of Wettability on Relative Permeability. JPT 39(11): 1453-1468. SPE-16323-PA. DOI: 10.2118/16323-PA.
Anderson, W.G. 1987b. Wettability Literature Survey—Part 6:The Effects of Wettability on Waterflooding. JPT 39 (12):1605-1622. SPE-16471-PA. DOI: 10.2118/16471-PA.
Baig, T., Droegemueller, U., and Gringarten, A.C. 2005. Productivity Assessment of Fracturedand Nonfractured Wells in a Lean/Intermediate Low-Permeability Gas CondensateReservoir. Paper SPE 93136 presented at the SPE Europec/EAGE Conference,Madrid, 13-16 June. DOI: 10.2118/93136-MS.
Barnum, R.S., Brinkman, F.P., Richardson, T.W., and Spillette, A.G. 1995. Gas Condensate Reservoir Behaviour:Productivity and Recovery Reduction Due to Condensation. Paper SPE 30767presented at the SPE Annual Technical Conference and Exhibition, Dallas, 22-25October. DOI: 10.2118/30767-MS.
Cimolai, M.P., Gies, R.M., Bennion, D.B., and Myers, D.L. 1993. Mitigating Horizontal Well FormationDamage in a Low-Permeability Conglomerate Gas Reservoir. Paper SPE 26166presented at the SPE Gas Technology Symposium, Calgary, 28-30 June. DOI:10.2118/26166-MS.
Economides, M.J., Cikes, M., Pforter, H., Udick, T.H., and Uroda, P. 1989.The Stimulation of a Tight,Very-High-Temperature Gas-Condensate Well. SPEFE 4 (1):63-72. SPE-15239-PA. DOI: 10.2118/15239-PA.
El-Banbi, A., McCain, W.D., and Semmelbeck, M.E. 2000. Investigation of Well Productivity inGas-Condensate Reservoirs. Paper SPE 59773 presented at the SPE/CERI GasTechnology Symposium, Calgary, 3-5 April. DOI: 10.2118/59773-MS.
Engineer, R. 1985. Cal CanalField, California: Case History of a Tight and Abnormally PressuredGas-Condensate Reservoir. Paper SPE 13650 presented at the SPE CaliforniaRegional Meeting, Bakersfield, California, 27-29 March. DOI:10.2118/13650-MS.
Fahes, M. 2006. Wettability Alteration From Liquid-Wetting to IntermediateGas-Wetting at High Temperatures. PhD dissertation. London: Imperial CollegeLondon.
Fevang, Ø. and Whitson, C.H. 1996. Modeling Gas-Condensate WellDeliverability. SPERE 11 (4): 221-230. SPE-30714-PA. DOI:10.2118/30714-PA.
Haimson, B. and Fairhurst, C. 1969. Hydraulic Fracturing inPorous-Permeable Materials. JPT 21 (7): 811-817. SPE-2354-PA.DOI: 10.2118/2354-PA.
Hinchman, S.B. and Barree, R.D. 1985. Productivity Loss in Gas-CondensateReservoirs. Paper SPE 14203 presented at the SPE Annual TechnicalConference and Exhibition, Las Vegas, Nevada, 22-26 September. DOI:10.2118/14203-MS.
Li, K. and Firoozabadi, A 2000. Experimental Study of WettabilityAlteration to Preferential Gas-Wetting in Porous Media and Its Effects.SPEREE 3 (2): 139-149. SPE-62515-PA. DOI: 10.2118/62515-PA.
Mahadevan, J. and Sharma, M.M. 2005. Factors Affecting Cleanup of WaterBlocks: A Laboratory Investigation. SPEJ 10 (3): 238-246.SPE-84216-PA. DOI: 10.2118/84216-PA.
Penny, G.S., Conway, M.W., and Briscoe, J.E. 1983. Enhanced Load Water-RecoveryTechnique Improves Stimulation Results. Paper SPE 12149 presented at theSPE Annual Technical Conference and Exhibition, San Francisco, 5-8 October.DOI: 10.2118/12149-MS.
Sognesand, S. 1991. Long-TermTesting of Vertically Fractured Gas Condensate Wells. Paper SPE 21704presented at the 1991 Production and Operations Symposium, Oklahoma City,Oklahoma, 7-9 April. DOI: 10.2118/21704-MS.
Tang, G.-Q. and Firoozabadi, A. 2002. Relative Permeability Modification inGas/Liquid Systems Through Wettability Alteration to Intermediate GasWetting. SPEREE 5 (6): 427-436. SPE-81195-PA. DOI:10.2118/81195-PA.
Tang, G. and Firoozabadi, A. 2003. Wettability Alteration to IntermediateGas-Wetting in Porous Media at Elevated Temperatures. Transport in PorousMedia 52: 185-211.