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Design And Analysis Of Geothermal Wellbore Energy Conversion System Working On Zero Mass Withdrawal Principle, Ildar Akhmadullin Jan 2016

Design And Analysis Of Geothermal Wellbore Energy Conversion System Working On Zero Mass Withdrawal Principle, Ildar Akhmadullin

LSU Doctoral Dissertations

This project is sponsored by the Department of Energy of the United States and dedicated to development of electricity production from the low-enthalpy geothermal reservoirs. The prime interest are reservoirs that are characterized by low temperature of heat source located in deep saline aquifers with high permeable rock. Usually energy production from these resources are not economical by using a conventional binary power plant approach. The presented PhD work is a study of a new system that utilizes a single-well technology and working on supercritical power cycle (PC). The wellbore energy conversion system is operating with Zero Mass Withdrawal (ZMW) …


Application Of The Variational Fracture Model To Hydraulic Fracturing In Poroelastic Media, Chukwudi Chukwudozie Jan 2016

Application Of The Variational Fracture Model To Hydraulic Fracturing In Poroelastic Media, Chukwudi Chukwudozie

LSU Doctoral Dissertations

Hydraulic fracturing has persisted through the use of simple numerical models to describe fracture geometry and propagation. Field tests provide evidence of interaction and merging of multiple fractures, complex fracture geometry and propagation paths. These complicated behaviors suggest that the simple models are incapable of serving as predictive tools for treatment designs. In addition, other commonly used models are designed without considering poroelastic effects even though a propagating hydraulic fracture induces deformation of the surrounding porous media. A rigorous hydraulic fracturing model capable of reproducing realistic fracture behaviors should couple rock deformation, fracture propagation and fluid flow in the both …


Simulation Studies For Relative Importance Of Unconventional Reservoir Subgrid Scale Physics Parameters, Yaakoub Youssef El Khamra Jan 2016

Simulation Studies For Relative Importance Of Unconventional Reservoir Subgrid Scale Physics Parameters, Yaakoub Youssef El Khamra

LSU Doctoral Dissertations

In this endeavor we attempt to better understand gas transport in shale gas reservoirs, specifically the impact and effects of different physical phenomena. We start by documenting the nature of the reservoirs and the need for accurate modeling of various physical phenomena in multiple interconnected continua. The physical phenomena of interest include non-linear Forchheimer flow, Knudsen diffusion in the form of slip "Klinkenberg" flow and adsorption/desorption. The numerical methods used in the reservoir simulator are also introduced, along with a derivation of the main equations used. Various verification and validation results are compared against manufactured and analytical solutions and finally …


Development Of Single-Well Gas Assisted Gravity Drainage Process For Enhanced Oil Recovery, Bikash Deep Saikia Jan 2016

Development Of Single-Well Gas Assisted Gravity Drainage Process For Enhanced Oil Recovery, Bikash Deep Saikia

LSU Doctoral Dissertations

EOR application in prolific deepwater Gulf of Mexico (DGOM) reservoirs has remained a challenge. Exorbitant well cost (>200M$) precludes having extensive injection patterns and very characteristics of the reservoirs themselves are partly to blame for negligible EOR activity in DGOM. We have been able to develop and demonstrate a novel design in the form of Single Well – Gas Assisted Gravity Drainage (SW-GAGD) process, which is potentially cost effective, at the same time ensuring very high oil recoveries. In this design, a single well acts as an injector as well as a producer, thereby minimizing well cost. The efficacy …


Statistical Reservoir Characterization, Simulation, And Optimization Of Field Scale-Gas Assisted Gravity Drainage (Gagd) Process With Uncertainty Assessments, Watheq Jasim Mohammed Al-Mudhafar Jan 2016

Statistical Reservoir Characterization, Simulation, And Optimization Of Field Scale-Gas Assisted Gravity Drainage (Gagd) Process With Uncertainty Assessments, Watheq Jasim Mohammed Al-Mudhafar

LSU Doctoral Dissertations

Unlike the Continuous Gas Injection (CGI) and Water-Alternative Gas (WAG), the Gas Assisted Gravity Drainage (GAGD) process takes advantage of the natural segregation of reservoir fluids to provide gravity-stable oil displacement. The gas is injected through existing vertical wells to formulate a gas cap to allow oil and water drain down to the horizontal producer (s). Therefore, the GAGD process was implemented through immiscible and miscible injection modes to improve oil recovery in a sector of the main pay/upper sandstone member in the South Rumaila oil field, located in Iraq. A high-resolution geostatistical reservoir characterization model was constructed to model …


Modelling Hydraulic Fracturing Propagation In Heterogeneous Reservoirs Using Cohesive Zone Methods, Miguel Alejandro Gonzalez-Chavez Jan 2016

Modelling Hydraulic Fracturing Propagation In Heterogeneous Reservoirs Using Cohesive Zone Methods, Miguel Alejandro Gonzalez-Chavez

LSU Doctoral Dissertations

The recent success in exploiting low permeability shale reservoirs has heavily relied on hydraulic fracturing to produce hydrocarbons economically in disadvantaged reservoir conditions. Although horizontal drilling significantly increases the contact area between the wellbore and the reservoir, the objective of hydraulic fracturing is set on creating further expanded conductive flow paths into the reservoir. This research uses cohesive zone method to numerically simulate hydraulic fracture propagation in the presence of natural fractures in two- and three-dimensional model. The Cohesive element approach limits fracture propagation to some predefined paths. However, in highly fractured formations since hydraulic fractures are growing through a …


Application Of The Finite Element Method To Solve Coupled Multiphysics Problems For Subsurface Energy Extraction, Milad Ahmadi Jan 2016

Application Of The Finite Element Method To Solve Coupled Multiphysics Problems For Subsurface Energy Extraction, Milad Ahmadi

LSU Doctoral Dissertations

Fractures are a source of extra compliance in the rock mass. Fracture compliance can estimate the fracture roughness and the type of fluid filling the fracture. The focus of this research study in chapter 2 is to illustrate how the compliance ratio of rough fractures can diverge from the compliance ratio of smooth fractures. The imperfect interface of the fracture is modeled with saw-tooth-like structures. The defined saw-tooth-like structures of contact asperities impose an in-plane asymmetry in the shear direction. The compliance ratio of the rough fracture is larger than the compliance ratio of the smooth fracture. Interlocking and riding …


Mathematical Scaling And Statistical Modeling Of Geopressured Geothermal Reservoirs, Esmail Ansari Jan 2016

Mathematical Scaling And Statistical Modeling Of Geopressured Geothermal Reservoirs, Esmail Ansari

LSU Doctoral Dissertations

The interest for developing geopressured-geothermal reservoirs along the US Gulf Coast is increasing for securing energy needs and reducing global warming. Identifying the most attractive candidate reservoirs for geothermal energy production requires quick and simple models. Analytical models are not always available and simulating each case individually is expensive. The use of scaling and statistical modeling is one approach to translate the output of a simulator into quick models with general applicability at all scales. The developed models can quickly estimate temperature and thermal energy recovery from the geopressured-geothermal reservoirs. These models can screen large databases of reservoirs to select …


Impacts Of Rock-Brine Interactions On Petrophysical Properties Of A Sandstone Reservoir, Utilizing Geochemical And Pore Network Modeling, Masoud Safari-Zanjani Jan 2016

Impacts Of Rock-Brine Interactions On Petrophysical Properties Of A Sandstone Reservoir, Utilizing Geochemical And Pore Network Modeling, Masoud Safari-Zanjani

LSU Doctoral Dissertations

Unfavorable consequences of geochemical reactions, such as calcite and silica scaling, in geothermal power plant surface facilities have been discussed in many recent studies. However, the impact of brine-rock interactions related to geothermal projects on reservoir properties has not been addressed fully. In this study, interactions between geothermal fluid and reservoir rocks in two fields located in Vermilion Parish, LA, and Chocolate Bayou, TX, are examined using geochemical modeling. The studied reservoir belongs to the Frio formation. In the geochemical models, the brine is cooled down to the estimated output temperature of a geothermal heat exchanger and re-equilibrated. Then, brine-rock …