WAG May Improve Gas-Condensate Recovery

Cullick, A.S.; Lu, Hao; Jones, L.G.; Cohen, M.F.; Watson, John

doi:10.2118/19114-pa

Cited by 18 publications

(6 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Some researchers have suggested that the magnitude of the water relative permeability endpoint has only a small effect on WAG recovery. 45 Gas relative permeabilities measured under three-phase flow conditions with CO 2 are much lower than with N 2 . This could result in lower total mobility and lower injectivity than would be predicted if nitrogen relative permeability data were used to calibrate the simulator.…”

Section: Reservoir Heterogeneity 4 Capillary Forces 5 Dynamics Of Wmentioning

confidence: 91%

“…Recently studies 44,45 have been conducted that show that the use of the WAG processes in gas condensate recovery may improve sweep efficiency. WAG is effective in recovering significantly more condensate with less injected gas than continuous gas injection and could substantially improve economics.…”

Section: Gas Reservoir Uses Of Wagmentioning

confidence: 99%

“…100 Unfavorable mobility miscible displacements lead to crossflow from the low permeability layer to an adjacent higher permeability layer and tend to reduce frontal advancement in the lower permeability layer. 45 Pizarro and Lake 101 studied the effect of heterogeneity on injectivity through geostatistical analysis and autocorrelation of the reservoir permeability distribution. Injectivity in a heterogeneous reservoir is a function of 10 parameters:…”

Section: Reservoir Heterogeneity 4 Capillary Forces 5 Dynamics Of Wmentioning

confidence: 99%

See 2 more Smart Citations

A Literature Analysis of the WAG Injectivity Abnormalities in the CO2 Process

Grigg

2000

SPE/DOE Improved Oil Recovery Symposium

View full text Add to dashboard Cite

TX 75083-3836, U.S.A., fax 01-972-952-9435. 3. 3 nitrogen-miscible projects 4. 1 hydrocarbon-immiscible 5. 1 nitrogen-and hydrocarbon-immiscible 6. 6 nitrogen-immiscible CO 2 projects continue to grow in numbers. Immiscible CO 2 projects have dropped to zero while ten new miscible CO 2 projects were planned as of January 1998. Brock and Bryan 2 presented a summary of CO 2 EOR projects and reviewed the performance of 30 full-scale field projects and field pilots up to 1987. In 1992 there were 45 active CO 2 projects in the U.S. 3 Initially the industry outlook was pessimistic; however, by 1992 most projects had been shown to be technically and economically successful. In a number of projects, the production performance has been better than was anticipated. 3 At the beginning of 1998 and based on 1997 production figures, the U.S. production from gas injected EOR was estimated at 307,544 b/d or approximately 4.7% of the total oil production in the US. Oil production from CO 2 activity alone contributed nearly 179,000 b/d, which is an increase of 4.9% over 1996 production attributable to CO 2 production and represents 2.8% of the 1997 US oil production of 6.4 MM bopd. 1 The Permian Basin of west Texas and southeastern New Mexico remains a very active area for CO 2 projects. Eight of the ten planned projects are in the Permian Basin. 1 However, new CO 2 EOR projects are possible for areas of California,

show abstract

Section: Reservoir Heterogeneity 4 Capillary Forces 5 Dynamics Of Wmentioning

confidence: 91%

Section: Gas Reservoir Uses Of Wagmentioning

confidence: 99%

Section: Reservoir Heterogeneity 4 Capillary Forces 5 Dynamics Of Wmentioning

confidence: 99%

See 1 more Smart Citation

A Literature Analysis of the WAG Injectivity Abnormalities in the CO2 Process

Grigg

2000

SPE/DOE Improved Oil Recovery Symposium

View full text Add to dashboard Cite

show abstract

“…Abel et al (1970) observed that the higher the injection pressure is, the higher the recovery of condensate oil will be. Cullick et al (1993) reported that gas-water alternating injection can significantly improve the recovery of stratified condensate gas reservoir contrasted to continuous injection if the high permeability strips exist. Edmond (2006) showed that CO 2 injection is very effective to improve the recovery of condensate gas reservoir by reducing the surface tension.…”

Section: Introductionmentioning

confidence: 99%

Characteristics and quantitative study on gas breakthrough in developing Yaha-2 condensate gas reservoir in Tarim Basin, China

Xia

Liu

Jiao

et al. 2018

Energy Exploration & Exploitation

View full text Add to dashboard Cite

In order to keep the formation pressure be larger than the dew-point pressure to decrease the loss of condensate oil, cyclic gas injection has been widely applied to develop condensate gas reservoir. However, because the heterogeneity and the density difference between gas and liquid are significant, gas breakthrough appears during cyclic gas injection, which apparently impacts the development effects. The gas breakthrough characteristics are affected by many factors, such as geological features, gas reservoir properties, fluid properties, perforation relations between injectors and producers, and operation parameters. In order to clearly understand the gas breakthrough characteristics and the sensitivity to the parameters, Yaha-2 condensate gas reservoir in Tarim Basin was taken as an example. First, the gas breakthrough characteristic of different perforation relations by injecting natural gas was studied, and the optimal relation was achieved by comparing the sweep efficiency. Then, the designs of orthogonal experiments method were employed to study the sensitivity of gas breakthrough to different parameters. Meanwhile, the characteristic parameters, such as gas breakthrough time, dimensionless gas breakthrough time, and sweep volume, were calculated and the prediction models were achieved. Finally, the prediction models were applied to calculate the gas breakthrough time and sweep volume in Yaha-2 condensate gas reservoir in Tarim Basin. The reliability of the model was verified at the same time. Please see the Appendix for the graphical representation of the abstract.

show abstract

“…Ahmed et al(1998) analyzed the effectiveness of lean gas, nitrogen and carbon dioxide in a "Huff and Puff" injection manner for condensate removal concluding that Huff and Puff injection was most productive when done before the maximum liquid drop out is reached. Cullick et al (1993) performed some simulation and experimental work on the effectiveness of water alternating gas (WAG) for improving deliverability in condensate reservoirs.…”

Section: Introductionmentioning

confidence: 99%

Correlating Wettability Alteration with Changes in Eelative Permeability of Gas Condensate Reservoirs

Gilani

Sharma

Torres

et al. 2011

SPE International Symposium on Oilfield Chemistry

View full text Add to dashboard Cite

In gas condensate reservoirs, considerable productivity loss occurs after the pressure near the production wells drops below the dew point of the hydrocarbon fluids. Over the years, several methods have been proposed to restore gas production rates after a decline in well productivity owing to condensate and/or water blocking. These methods such as gas recycling, hydraulic fracturing and solvent injection have shown to restore the production on a temporary basis only. Altering the wettability of reservoir rock using fluoro-chemical treatments has proved to be a viable and permanent solution to this problem. The selection of these treatments from a large pool of potentially effective chemicals requires extensive laboratory testing which requires time and money.In this paper, we present data that correlates changes in wettability with improvements in relative permeability. Imbibition, contact angle and X-ray photoelectron spectroscopy (XPS) tests along with coreflood results are used to characterize wettability changes. XPS tests, drop tests and core flood experiments were conducted and correlated with each other. It is shown that XPS analysis and imbibition tests provide a quantitative measure of chemical adsorption and surface modification, but only a qualitative measure of the possible change in relative permeability. As such these simple analytical tools may be used as a screening tool. A positive but imperfect empirical correlation was obtained with results from core flood experiments. The varying concentration of fluorine observed on the rock surface was found to be directly correlated to the wettability change in the rock, which in turn is responsible for improving the deliverability of wells in gas condensate/volatile oil reservoirs.The method discussed in this paper can be successfully used to identify chemical treatments that can change rock wettability and, therefore, relative permeability. This provides a simple and inexpensive way to screen chemicals as wettability altering agents and relative permeability modifiers. In this way the number of HTHP core floods needed is minimized which saves time, cost and effort. IntroductionGas condensate reservoirs are becoming more common as the petroleum industry goes to greater depths to explore for oil and gas. When we compare dry-gas reservoirs with gas-condensate reservoirs, there are many factors which affect the performance of gas-condensate reservoir during the exploitation process that need to be understood. As the reservoir pressure declines below the dew point of the fluid, a liquid rich phase starts to drop out of the gas phase. This liquid rich phase is termed "condensate" and the phenomenon is called "condensate banking". Since the largest pressure drop occurs near the producing wells, the formation of a condensate phase usually occurs as a near well bore phenomenon. As the pressure continues to drop, the liquid continues to accumulate occupying the rock pores leading to a decrease in the effective permeability to gas.Several cases have been reported i...

show abstract

WAG May Improve Gas-Condensate Recovery

Cited by 18 publications

References 7 publications

A Literature Analysis of the WAG Injectivity Abnormalities in the CO2 Process

A Literature Analysis of the WAG Injectivity Abnormalities in the CO2 Process

Characteristics and quantitative study on gas breakthrough in developing Yaha-2 condensate gas reservoir in Tarim Basin, China

Correlating Wettability Alteration with Changes in Eelative Permeability of Gas Condensate Reservoirs

Contact Info

Product

Resources

About