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Optimal Operating Strategy For Wells With Downhole Water Sink Completions To Control Water Production And Improve Performance, Ozan Arslan Jan 2005

Optimal Operating Strategy For Wells With Downhole Water Sink Completions To Control Water Production And Improve Performance, Ozan Arslan

LSU Doctoral Dissertations

Downhole water sink (DWS) technology is an alternative to conventional limited-entry completions to control water production in wells with bottom water drive. DWS wells comprise two completions: the bottom completion produces water and keeps the top completion open to oil inflow. The system performance depends on careful manipulation of the top and bottom rates to maximize oil productivity and produce oil-free water from the bottom completion. Conventional nodal analysis cannot provide a solution for DWS wells because the critical rates for water coning change with water drainage rate. A reservoir simulator is used to model two-phase flow to the dual …


Shaly Sand Interpretation Using Cec-Dependent Petrophysical Parameters, Fnu Kurniawan Jan 2005

Shaly Sand Interpretation Using Cec-Dependent Petrophysical Parameters, Fnu Kurniawan

LSU Doctoral Dissertations

This research explores the characterization of petrophysical parameters such as cementation exponent, saturation exponent and effective porosity as a function of cations exchange capacity (CEC), and its impact on shaly sand interpretation. Experimental and field data were used in the study. The latest LSU model for shaly sand interpretation uses of two cementation exponents, mf and mc, to represent the tortuosity of electric current path in free water and clay bound water, respectively. Experimental measurements on three types of rock, clean sand, shaly sand and pure shale using different brine salinity, were conducted to validate the use of these two …


Geostatistical Integration Of Geophysical, Well Bore And Outcrop Data For Flow Modeling Of A Deltaic Reservoir Analogue, Hong Tang Jan 2005

Geostatistical Integration Of Geophysical, Well Bore And Outcrop Data For Flow Modeling Of A Deltaic Reservoir Analogue, Hong Tang

LSU Doctoral Dissertations

Significant world oil and gas reserves occur in deltaic reservoirs. Characterization of deltaic reservoirs requires understanding sedimentary and diagenetic heterogeneity at the submeter scale in three dimensions. However, deltaic facies architecture is complex and poorly understood. Moreover, precipitation of extensive calcite cement during diagenesis can modify the depositional permeability of sandstone reservoir and affect fluid flow. Heterogeneity contributes to trapping a significant portion of mobile oil in deltaic reservoirs analogous of Cretaceous Frontier Formation, Powder River Basin, Wyoming. This dissertation focuses on 3D characterization of an ancient deltaic lobe. The Turonian Wall Creek Member in central Wyoming has been selected …


Long Term Pressure Behavior In Turbidite Reservoirs, Feng Wang Jan 2005

Long Term Pressure Behavior In Turbidite Reservoirs, Feng Wang

LSU Doctoral Dissertations

In this study, we investigated several possible mechanisms that would give rise to the anomalous pressure behavior (early concave-up on Horner plot or upward drift on the derivative curve of the log-log plot and asymmetry between the pressure drawdown and buildup behavior) sometimes encountered in the turbidite reservoirs in GOM primarily using numerical simulation and 2-level experimental designs. We ascertained the most influential parameters to the pressure behavior and identified that multilayer commingled system and the leaky compartment model are the most probable mechanisms to cause the anomalous behavior due to layer or zone property contrast to a certain degree. …


Mechanisms And Control Of Water Inflow To Wells In Gas Reservoirs With Bottom Water Drive, Miguel Armenta Jan 2003

Mechanisms And Control Of Water Inflow To Wells In Gas Reservoirs With Bottom Water Drive, Miguel Armenta

LSU Doctoral Dissertations

Water inflow may cease production of gas wells, leaving a significant amount of gas in the reservoir. Conventional technologies of gas well dewatering remove water from inside the wellbore without controlling water at its source. This study addresses mechanisms of water inflow to gas wells and a new completion method to control it. In a vertical oil well, the water cone top is horizontal, but in a gas well, the gas/water interface tends to bend downwards. It could be economically possible to produce gas-water systems without water breakthrough. Non-Darcy flow effect (NDFE), vertical permeability, aquifer size, density of well perforation, …


Improved Bottomhole Pressure Control For Underbalanced Drilling Operations, Carlos Perez-Tellez Jan 2003

Improved Bottomhole Pressure Control For Underbalanced Drilling Operations, Carlos Perez-Tellez

LSU Doctoral Dissertations

Maintaining underbalanced conditions from the beginning to the end of the drilling process is necessary to guarantee the success of jointed-pipe underbalanced drilling (UBD) operations by avoiding formation damage and potential hazardous drilling problems such as lost circulation and differential sticking. However, maintaining these conditions is an unmet challenge that continues motivating not only research but also technological developments. This research proposes an UBD flow control procedure, which represents an economical method for maintaining continuous underbalanced conditions and, therefore, to increase well productivity by preventing formation damage. It is applicable to wells that can flow without artificial lift and within …


Analysis Of Diagnostic Testing Of Sustained Casing Pressure In Wells, Rong Xu Jan 2002

Analysis Of Diagnostic Testing Of Sustained Casing Pressure In Wells, Rong Xu

LSU Doctoral Dissertations

Over 8,000 wells in the Gulf of Mexico exhibit sustained casing pressure (SCP). SCP is defined as “any measurable casing pressure that rebuilds after being bled down, attributable to cause(s) other than artificially applied pressures or temperature fluctuations in the well”. The Minerals Management Service (MMS) regulations consider SCP hazardous and, in principle, require its elimination. In some cases the agency may allow continuing production at a well with SCP by granting a temporary “departure” permit. The departure permits are based on diagnostic tests involving pressure bleed-down through a 0.5-inch needle valve followed by closing the valve and recording pressure …


Numerical Reservoir Characterization Using Dimensionless Scale Numbers With Application In Upscaling, Djuro Novakovic Jan 2002

Numerical Reservoir Characterization Using Dimensionless Scale Numbers With Application In Upscaling, Djuro Novakovic

LSU Doctoral Dissertations

Dimensionless space provides a tool for analyzing the behavior of complex systems described by mathematical relationships. The limited application of dimensionless variables in numerical reservoir simulation and experimental design motivated the development of a complete set of dimensionless scaling groups. Inspectional analysis yielded 8 dimensionless groups completely describing the flow system. Further analysis of fluid interaction reduced the number of dimensionless groups to 7. The newly developed dimensionless equations and groups were used for analytical and numerical reservoir characterization, quantifying the behavior of differential and difference equations employed in fluid flow in three-dimensional porous media. The behavior of the dimensionless …


Numerical Study Of Water Coning Control With Downhole Water Sink (Dws) Completions In Vertical And Horizontal Wells, Solomon Ovueferaye Inikori Jan 2002

Numerical Study Of Water Coning Control With Downhole Water Sink (Dws) Completions In Vertical And Horizontal Wells, Solomon Ovueferaye Inikori

LSU Doctoral Dissertations

Approximately 2.5 billion dollars is spent annually to solve the problem of produced water in oil and gas wells. Downhole Water Sink (DWS) technology is one industry solution to control water coning in oil wells. DWS technology involves the segregated production of oil and water through separate completions with zonal isolation packer. However, several problems have been experienced in the application of the technology in watered-out oil wells. This study identified two factors that could aid in a better modeling of the technology in old vertical wells – inclusion of capillary transition pressures and relative permeability hysteresis. It also identified …


Experimental Evaluation Of Control Fluid Fallback During Off-Bottom Well Control In Vertical And Deviated Wells, Fernando Sebastian Flores-Avila Jan 2002

Experimental Evaluation Of Control Fluid Fallback During Off-Bottom Well Control In Vertical And Deviated Wells, Fernando Sebastian Flores-Avila

LSU Doctoral Dissertations

This study measured the liquid fallback during simulated blowout conditions. The purpose of the study was to establish a basis for developing a procedure for controlling blowouts that relies on the accumulation of liquid kill fluid injected while the well continues to flow. The results from experiments performed with air, water, 10.5 ppg and 12.0 ppg mud in an experimental 48 ft flow loop at 0°, 20°, 40°, 60° and 75° deviation angles from the vertical, as well as results from full-scale experiments performed with natural gas and water based drilling fluid in a vertical 2787-foot deep research well, are …


Log-Derived Cation Exchange Capacity Of Shaly Sands : Application To Hydrocarbon Detection And Drilling Optimization, Gamze Ipek Jan 2002

Log-Derived Cation Exchange Capacity Of Shaly Sands : Application To Hydrocarbon Detection And Drilling Optimization, Gamze Ipek

LSU Doctoral Dissertations

Researchers at Louisiana State University, LSU, have introduced several petrophysical models expressing the electric properties of shaly sands. These models, to be used for hydrocarbon detection, are based on the Waxman and Smits concept of supplementing the water conductivity with a clay counterions conductivity. The LSU models also utilize the Dual Water theory, which relates each conductivity term to a particular type of water, free and bound, each occupying a specific volume of the total pore space. The main difference between these models and the other shaly sand models is that the counterion conductivity is represented by a hypothetical sodium …


Analytical Model To Control Off - Bottom Blowouts Utilizing The Concept Of Simultaneous Dynamic Seal And Bullheading, Victor Gerardo Vallejo-Arrieta Jan 2002

Analytical Model To Control Off - Bottom Blowouts Utilizing The Concept Of Simultaneous Dynamic Seal And Bullheading, Victor Gerardo Vallejo-Arrieta

LSU Doctoral Dissertations

The current methods for off - bottom control of blowouts involve pumping kill fluid into the well through an injection string. These are the dynamic kill and the momentum kill. The dynamic kill, which is based on the steady state system analysis approach, and the momentum kill, that is loosely based on the Newton's Second Law of Motion, have been used extensively in off-bottom control of actual blowouts. A comprehensive study of these two concepts was performed. The review included an analytical analysis of the published design techniques for both of these methods. The application of these techniques to several …