Predicting Recovery of Gas Reservoirs Under Waterdrive Conditions

Hower, T.L.; Jones, Robert E.

doi:10.2118/22937-ms

Cited by 11 publications

(5 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The average k values finally obtained from the calibration are given in Table 3. Consistent with other gas fields of the sedimentary Po River basin [ Baù et al , 1999; Teatini et al , 2000; Ferronato et al , 2004; Stright et al , 2005], the aquifer permeability to water is found to be generally less than reservoir permeability, mainly due to the effect of the trapped gas saturation in the water invaded zone that develops during gas production [ Hower and Jones , 1991]. An example of the groundwater model outcome for the aquifer connected to the C1 pool is shown in Figure 8.…”

Section: Application To the Lombardia Gas Fieldsupporting

confidence: 75%

Geomechanical response to seasonal gas storage in depleted reservoirs: A case study in the Po River basin, Italy

et al. 2011

View full text Add to dashboard Cite

[1] Underground gas storage (UGS) in depleted hydrocarbon reservoirs is a strategic practice to cope with the growing energy demand and occurs in many places in Europe and North America. In response to summer gas injection and winter gas withdrawal the reservoir expands and contracts essentially elastically as a major consequence of the fluid (gas and water) pore pressure fluctuations. Depending on a number of factors, including the reservoir burial depth, the difference between the largest and the smallest gas pore pressure, and the geomechanical properties of the injected formation and the overburden, the porous medium overlying the reservoir is subject to three-dimensional deformation with the related cyclic motion of the land surface being both vertical and horizontal. We present a methodology to evaluate the environmental impact of underground gas storage and sequestration from the geomechanical perspective, particularly in relation to the ground surface displacements. Long-term records of injected and removed gas volume and fluid pore pressure in the "Lombardia" gas field, northern Italy, are available together with multiyear detection of vertical and horizontal west-east displacement of the land surface above the reservoir by an advanced permanent scatterer interferometric synthetic aperture radar (PSInSAR) analysis. These data have been used to calibrate a 3-D fluid-dynamic model and develop a 3-D transversally isotropic geomechanical model. The latter has been successfully implemented and used to reproduce the vertical and horizontal cyclic displacements, on the range of 8-10 mm and 6-8 mm, respectively, measured between 2003 and 2007 above the reservoir where a UGS program has been underway by Stogit-Eni S.p.A. since 1986 following a 5 year field production life. Because of the great economical interest to increase the working gas volume as much as possible, the model addresses two UGS scenarios where the gas pore overpressure is pushed from the current 103%p i , where p i is the gas pore pressure prior to the field development, to 107%p i and 120%p i . Results of both scenarios show that there is a negligible impact on the ground surface, with deformation gradients that remain well below the most restrictive admissible limits for the civil structures and infrastructures. Citation: Teatini, P., et al. (2011), Geomechanical response to seasonal gas storage in depleted reservoirs: A case study in the Po River basin, Italy,

show abstract

Section: Application To the Lombardia Gas Fieldsupporting

confidence: 75%

Geomechanical response to seasonal gas storage in depleted reservoirs: A case study in the Po River basin, Italy

et al. 2011

View full text Add to dashboard Cite

show abstract

“…Early water breakthrough in gas reservoirs has been attributed to geologic heterogeneity in several cases. 1,3,7,12,34 Figure 1: Simulated water saturation at breakthrough to a horizontal well. The gas-saturated zone has been filtered out; only water saturation is shown.…”

Section: Spe 107169mentioning

confidence: 99%

“…A key subsurface risk in gas reservoirs with a component of water drive is early water breakthrough. [3][4][5]7,8 In large-bore horizontal wells, early water breakthrough is a particularly serious threat to deliverability, because of the significant reduction in gas flow capacity associated with flowing entrained water to the surface. 4,[9][10][11] At best, substantial water production will require expensive processing facilities; at worst, it will effectively 'kill' the well.…”

Section: Introductionmentioning

confidence: 99%

Controls on Water Cresting in High-Productivity Horizontal Gas Wells

Sech¹,

Jackson²,

Hampson³

2007

Proceedings of EUROPEC/EAGE Conference and Exhibition

View full text Add to dashboard Cite

fax 01-972-952-9435. AbstractIt is widely agreed that gas reservoirs with a component of water drive should be produced at high rates to minimize the volume of gas which is trapped at high pressure by the advancing water (often termed 'outrunning the aquifer'). Yet high production rates are also associated with coning (in vertical wells) or cresting (in horizontal wells) of the encroaching water, leading to early water breakthrough. In vertical wells, the formation of an inverse gas cone means that high gas rates can be maintained post-breakthrough until almost the whole perforated interval is flowing water. However, in horizontal wells, water breakthrough is a serious threat to gas deliverability, because the inverse coning mechanism does not apply and the well rapidly loads with water. Consequently, it is not clear whether producing at high rates is the best strategy to maximize recovery in gas reservoirs developed using horizontal wells.We investigate the risk associated with producing horizontal wells at high rates by simulating gas recovery and aquifer response over a broad range of reservoir properties and production scenarios. We find that high rates always result in lower gas recovery unless the ratio of vertical to horizontal permeability is very low, in which case water cresting is suppressed. However, there are many instances where accelerating production recovers only slightly less gas over much shorter timescales, so may be economically favorable. Rate sensitivity increases in low permeability reservoirs with thin gas columns, because these conditions increase the tendency for water cresting, and decreases in reservoirs with strong aquifer support, since water breakthrough occurs regardless of the rate at which the well is produced. Our results can be used as a reference framework to rapidly assess gas production behavior and aquifer response within a wide range of field development scenarios.

show abstract

“…al. (9) included a water invaded zone having a constant trapped gas saturation and a pressure gradient due to the relative permeability at the trapped gas saturation in this zone.These analytical methods have one basic disadvantage. That is, by using the Material Balance equation in the gas reservoir, average pressure data and cumulative production data are used to represent the entire reservoir.…”

Section: Introductionmentioning

confidence: 99%

Future Performance Prediction for Water Drive Gas Reservoirs

Layne¹,

Numbere²,

Koederitz³

1993

Proceedings of SPE Annual Technical Conference and Exhibition

View full text Add to dashboard Cite

University ofMissouri-Rolla SPE members Copyrigbt 1993. Society ofPetroleum~Inc. This Paper prepmed forJll"""lltmon at lbe 68th Annuol TecbnicaI eonr...n.e ond ExbibiIion oflbe Sociely ofPetroleum Enainoen ho:Idin HOIIIIon, Texu 3-6 Oclobor 1993. Thispoper selectedforJll"""lltmol bylbe SPE Program CommitIIle foIIowinI nMew ofinfolmation contained in UI obotncIlUbmiIIIld bylbe IIIlhor(s). Contmts oflbe poper IS pracnted baw: not beennMewed by tbe Sociely ofPetroleum J!nIlin=n ond _lUbject to conection by tbe aulbon(s). The mataial .. presented does not.-i!y mIect lIlY position oftbe Sociely ofPetroleum EnP--. ito oflicen, or memben. Papen pracnted at SPE moetinIP _lUbject to publication nMew by EdiIorial CommitIIles oflbe Sociely of Petroleuin £nsjneeIs. Pamisaion to copy is nstric:ted to UI abIIrIct of not rncxe !ban JOO words. IIIusIIationI may not be copiod. The ahotnct IbouJd conlain conspicuous ocknowIedpIent of'lVll<:le and by whom !be poperis JlIl'I"IIled. Write LibnIian, SPE, P.o. Box 833836. RicIwdson, TX 75083-3836. U.S.A. Telex. 163245 SPEUT. AbstractThe development and application of a Boundary Element model for the prediction ofgas reservoir performance under water drive conditions is presented. The model retains the natural coupling of the gas reservoir with the aquifer and treats them as a two-region composite system. The diffusivity equation is written separately for each region and each is converted to a Boundary Integral equation . The two resulting equations ( non-linear for the gas reservoir and linear for the aquifer) are linked by the compatibility and continuity conditions on the gas/water interface boundary separating the two media. A modification of the Powell hybrid method was used to solve the final combined non-linear matrix.Output from the model include predictions ofthe pressures along the reservoir aquifer interface or gas-water-contact (GWC), the average pressure in the gas reservoir, and the average aquifer pressure.References and illustrations at the end of paperThese are plotted and presented as functions oftime. These plots can aid analytical predictions ofgas reservoir performance using the Material Balance Method.The model is validated by comparing its results with those using a finite difference simulator. The results show comparable accuracy with finite difference models but with less data input. This is a useful model for areally large and arbitrarily shaped systems such as reservoir/aquifer composites because it has less data requirements than conventional numerical models.

show abstract

Predicting Recovery of Gas Reservoirs Under Waterdrive Conditions

Cited by 11 publications

References 9 publications

Geomechanical response to seasonal gas storage in depleted reservoirs: A case study in the Po River basin, Italy

Geomechanical response to seasonal gas storage in depleted reservoirs: A case study in the Po River basin, Italy

Controls on Water Cresting in High-Productivity Horizontal Gas Wells

Future Performance Prediction for Water Drive Gas Reservoirs

Contact Info

Product

Resources

About