This case study investigated the effects of formation reservoir properties, aquifer influx, and production scheme on ultimate recovery and production behaviors of a gas condensate sandstone reservoir sand20 offshore vietnam. But, the measuring of bottomhole pressure to approach these curves needs much time and high expenses and also running. The novelty of this study is to evaluate eor performance of co2 huffnpuff in shale gas condensate reservoirs using experiments and numerical analysis. When the reservoir pressure is decreased lower than the dew point pressure in shale gas condensate reservoirs, condensate would be formed in the formation.
Based on known moles of gas and condensate, determine the fraction of produced gas and condensate in the reservoir fluid stream. Overview chapter 5 part 1 reservoir performance duration. The equations developed can used to form the basis of forecasting future production rates by capturing the relationship between cumulative fluid production and average reservoir pressure. A case study of gascondensate reservoir performance under bottom water drive mechanism tung v. Appendix a lists the commonly used units in gas reservoir engineering, along with their conversion factors. The gen eralized form is obtained by manipulation of martins. The development of gas condensate reservoirs by gas injection is treated in chapter 12. This procedure is applied with material balance requirements in generation of twocomponent, blackoil properties for gas condensates. This curve and its outcome equation can be applied for production schedule and maintenance management of well and reservoir. Appendix b includes some special physical and mathematical constants that are of particular interest in gas reservoir engineering. Summary this paper presents a generalized equation of state eos that represents several widely used cubic eoss. The first step of the study involved gathering north field reservoir data from previously published papers. Calculate the number of poundmoles in gas by dividing the gas condensate ratio gas volume in cubic feet per barrel of condensate by 379.
The importance of fluid characterization for diagnosing. Abstract gas condensate reservoirs exhibit complex coupling between phase. In addition, quantifying the effects of well and reservoir parameters on the performance of horizontal and vertical wells in gas condensate reservoirs is very important to decide what type well to utilize in a given reservoir. Gascondensate reservoirs differ from drygas reservoirs. When the pbhf is above dew point, the mw of the surface liquid is the highest. Calculate the number of poundmoles in gas by dividing the gascondensate ratio gas volume in cubic feet per barrel of condensate by 379. Modeling and optimization of the rich gascondensate reservoir. Understanding the behaviors of gas condensate reservoirs. Kleinsteiber has over 24 years of petroleum engineering experience and has authored or coauthored papers dealing with production decline type curve analysis, co2 flooding, and depletion of a rich gas. The calculations use results from cce and cvd experiments. This page discusses various aspects of gas reservoir performance, primarily to determine initial gas in place and how much is recoverable.
Developing an easytouse simulator to thermodynamic design. Determine the dewpoint pressure of this reservoir via marruffomaitahimrojas method. It has been known that volatile oil and gas condensate reservoirs cannot be modeled accurately with conventional blackoil models. Introduction gas condensate reservoirs mostly produce gas, with some liquid dropout, frequently occurring in the wellhead separators. Performance of bodcaw reservoir, cotton valley field cycling project, new methods of predicting gascondensate reservoir performance under cycling operations compared to field data. These reservoirs have a reservoir temperature located between the critical point and the cricondentherm on the reservoir fluids pressuretemperature diagram. Barnum brinkman fp, richardson rw spillette ag gas condensate reservoir afidick 12. An earlier probabilistic assessment for the case study reservoir was built based primarily on core data from two analogous reservoirs, one of which was from the same field, prior to the availability of bottom hole pressure and drawdown data. Accurate prediction of well reauirements in gas the relative significance of positive coupling and inertial effects on gas condensate relative yroauctlvlty ana condensation ecovery mea spe 30767, uctlon ijue to 8. A further complication of this problem is that the composition of the surface liquid also changes.
A commercial simulator was then used to carry out numerical reservoir simulation of fluid flow in the north field. Coats, sw inteow resoue development and engiaring, inc. Effect of horizontal well length variation on productivity. Ron terry discusses gas condensate reservoirs, calculating hydrocarbon. The results assume no aquifer influx and ignore the effect of rock and water compressibility. Therefore, an accurate and highly sophisticated prediction of the performance and recovery of such systems depends on a comprehensive. Simulation of gas condensate reservoir performance keith h. Modeling gas condensate reservoir fluid systems with an. Predicting reservoir performance with the tarner 5. Our registered office is at 21 bloomsbury street, london, united kingdom, wc1b 3hf introduction to reservoir simulation dr panteha ghahri. Existing uncertainty analysis inadequate for gas condensate field fielddevelopment planning compromised. However, to the authors knowledge, the workflow to build a benchmarked simulation model for gascondensate reservoir is not. Fundamentals of gas reservoir engineering, volume 23 elsevier.
Performance evaluation of co2 huffnpuff gas injection in. Gas condensate field uncertainty analysis drives improved. Agreement between resulting blackoil and fully compositional simulations of gas condensate reservoir depletion is demonstrated for a very rich, nearcritical. However, the enhanced condensate performance of co2 huffnpuff in shale reservoirs have not been investigated, especially in experimental aspects. Most known retrograde gascondensate reservoirs are in the range of 3000 to 8000 psi and 200400. Critical evaluation of empirical gas condensate correlations. Pdf this case study investigated the effects of formation reservoir properties, aquifer influx, and production scheme on ultimate recovery and. According to the previous studies, the addition of some nitrogen causes a considerable increase in mixture dew. Stanley kleinsteiber is a senior petroleum engineer with mha petroleum consultants inc.
The oga does not provide endorsements or investment recommendations. Understanding of phase and fluid flow behavior relationships is essential if we want to make accurate engineering computations for gascondensate systems e. Gas condensate wells simulation to optimize well flow. Distributions of pseudo components among phases in modified blackoil.
Consider a gascondensate reservoir with following properties. Oil and gas authority is a limited company registered in england and wales with registered number 09666504 and vat registered number 249433979. Spe, iniercomp resource development ana engineering, inc. It is shown that water drive can significantly increase the ultimate oil and gas recoveries of a gas condensate reservoir. Pdf a case study of gascondensate reservoir performance under. Kleinsteiber has over 24 years of petroleum engineering experience and has authored or coauthored papers dealing with production decline type curve analysis, co2 flooding, and depletion of a rich gas condensate reservoir by. Based on the monte carlo results from mbal, there is a 90 percent probability of the gas condensate reservoir to produce 360 bscf of gas and 23 mmstb of recoverable. Optimum production strategy was then formulated to maximize the hydrocarbon recovery while reducing the water treatment cost. To model the condensate banking or water influx effects on gascondensate reservoirs, both cartesian and radial models have been used in the.
Chapter 5, part 1 of the online course in applied petroleum reservoir engineering. At the time of discovery, gas condensates are often found as singlephase gas in the reservoir. Gas condensate reservoirs in niger delta and around the world are becoming increasingly important as a result of additional liquid recovery and increasing demand for light oil and natural gas. Pdf a case study of gascondensate reservoir performance.
The phase diagram e shows the r trograde gas must have a temperature higher than the critical temperature. This paper discusses performance of gas condensate reservoirs. Modelling and simulation of a gas condensate reservoir. During reservoir depletion liquid condense out of the gas. The gas is much more mobile than the condensate and, therefore, the gas condensate ratios gcr exhibited at surface are commonly higher than that of the reservoir fluid. Pdf gas condensate reservoir performance free download as pdf file. Its presence as a liquid phase depends on temperature and pressure conditions in the reservoir allowing condensation of liquid from vapor. Lean gas condensateleanlean gas condensate gas condensate rich gas condensaterichrich gas condensate gas condensate 0 0. Production with gor 100,000 scfbbl is commonly called lean or dry gas. A case study of gascondensate reservoir performance under bottom. An alternative approach inflow performance relationship ipr accuracy in the condensate reservoir is a longstanding problem in the oil industry. Condensate accumulation severely reduces the commercial production of shale gas condensate reservoirs. Understanding of phase and fluid flow behavior relationships is essential if we want to make accurate engineering computations for gas condensate systems e.
Gas production from gas condensate reservoirs using. Fully compositional simulators are more expensive, time consuming and have complex data requirement as compared to limited compositional. To model the condensate banking or water influx effects on gascondensate reservoirs, both cartesian and radial models have been used in the previous studies. Importance of water influx and waterflooding in gas. Gas reservoir management training course petroskills grm. Seeking ways to mitigate condensate in the formation and enhance both condensate and gas recovery in shale reservoirs has important. To resolve the problems caused by the assumptions inherent in the material. A case study of gascondensate reservoir performance under.
Compositional numerical model a case study of hai thach moc tinh fields find, read. This paper presents a new approach to project the gas phase ipr in condensate reservoirs. Basic introduction to reservoir fluid properties gas condensate volatile oil reservoir and well performance related to fluid properties 1. Inflow performance relationship ipr accuracy in the condensate reservoir is a longstanding problem in the oil industry. The importance of fluid characterization for diagnosing well. Gas condensate pvt what s really important and why. From experimental pvt analysis it was deduced that the fluid in the reservoir was a gas condensate which was lean and possessed a liquid dropout of 1. Simulation study of enhanced condensate recovery in a gascondensate reservoir iranian journal of chemical engineering, vol. Developing an easytouse simulator to thermodynamic.
Reservoir simulation models are commonly used to predict the performance of retrograde gas condensate reservoirs. Tran and others published production performance of gas condensate reservoirs. This case study investigated the effects of formation reservoir properties, aquifer influx, and production scheme on ultimate recovery and production behaviors of a gascondensate sandstone reservoir sand20 offshore vietnam. Gas condensate pvt petroleum reservoir pressure free. Simulation study of enhanced condensate recovery in a gas.
Pdf production performance of gas condensate reservoirs. Phase diagram of typical gas condensate reservoir3 figure 22. Agreement between resulting blackoil and fully compositional simulations of gas condensate reservoir depletion is demonstrated for a very rich, nearcritical condensate. A simulator is a program used to perform material balance calculations to determine pressure and saturation distribution of the reservoir as a function of time. Typical field performance of gas condensate gas and oil flow rates vs. Production performance analysis of sarkhoon gas condensate.
Once an accurate model was obtained, the following three solutions to. One variation to the blackoil approach is the modified blackoil mbo model that allows the use of a simple, and less expensive computational algorithm than a fully compositional model that can result in significant timesaving in full field studies. Gas condensate reservoirs differ from dry gas reservoirs. Production performance analysis of sarkhoon gas condensate reservoir article in journal of petroleum science and engineering 751. Gas condensate wells simulation to optimize well flow performance using tubing equations coupled with inflowperformancerelation ipr curve abstract fulltext html xml download as pdf size.
Enhancing recovery and sensitivity studies in an unconventional tight gas condensate reservoir min wang1 shengnan chen1 menglu lin1 received. Simulation of gas condensate reservoir performance onepetro. Condensate gas is very similar to volatile oils in terms of the colour green, orange, brown, even clear and gravity 40 to 60 api of the produced oil. This is the only unique and accurate means of identifying gas condensate reservoirs. Phase behavior important to gas cycling projects is also covered. This paper presents a genertilzed equation of state eos that represents several widely used cubic eoss. Nevertheless, there are many other elements have to be considered into the calculation method and approach for extract accurate results. The development of gascondensate reservoirs by gas injection is treated in chapter 12. Jan 30, 2016 chapter 5, part 1 of the online course in applied petroleum reservoir engineering. However, the reservoir temperature of a condensate gas reservoir is greater than the critical temperature of the fluid, and so where a volatile oil is a liquid at original reservoir. Calculation of rate and ultimate recovery from gas condensate reservoirs. Wells performance is evaluated by ipr curves that show the relationship between bottomhole pressure and inflow rate. Natural gas condensate aka gas condensate, condensate, natural gas liquids is a lowdensity, highapi gravity liquid hydrocarbon phase that generally occurs in association with natural gas.
Fully compositional simulators are more expensive, time consuming and have complex data requirement as compared to limited compositional reservoir simulators. The gas is much more mobile than the condensate and, therefore, the gascondensate ratios gcr exhibited at surface are commonly higher than that of the reservoir fluid. Modeling gas condensate reservoir fluid systems with an equation of state is. The importance of specific pvt data are put in the context of their importance to specific mechanisms of recovery and flow behavior. Performance of a study of the arun retrograde gas reservoir. Parameters such as tubing size, skin factor, condensate gas ratio, wellhead pressure and water gas ratio are used to implement a sensitivity analysis in prosper. Performance analysis of compositional and modified black.
The model was calibrated against historical performance, including effects such as condensate banking and velocity stripping, and was. Reservoir performance an overview sciencedirect topics. Performance analysis of compositional and modified blackoil. The generalized form is obtained by manipulation of martins eos 1 and is applied in this study. Condensate and gas recovery from a gas condensate reservoir produced by depletion 2.