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Full-Text Articles in Chemical Engineering

Investigation Of Qualitative Methods For Diagnosis Of Poor Bit Performance Using Surface Drilling Parameters, Arash Aghassi Jan 2003

Investigation Of Qualitative Methods For Diagnosis Of Poor Bit Performance Using Surface Drilling Parameters, Arash Aghassi

LSU Master's Theses

Bit performance in deep shale when using water-based mud is typically poor. This study is part of a larger research project to improve that performance entitled "Automated Rig Controls for Improved Drilling Costs." The objective of the project is diagnosis of changes in drill bit performance to provide a logical basis for automating draw works control, maximizing bit performance, and reducing drilling costs. The specific goal of this study is a means to diagnose bit performance, specifically to identify bit balling and lithology changes, using real-time drilling data. The research began by identifying symptoms relating to specific causes of bit …


Using Psychotherapy Techniques To Reveal Misconceptions And Improve Learning, Paul Michael Santi, Michele M. Santi Jan 2003

Using Psychotherapy Techniques To Reveal Misconceptions And Improve Learning, Paul Michael Santi, Michele M. Santi

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

When students are aware that they do not understand a concept, the main impediment to developing an understanding is their willingness to ask questions of the instructor or of fellow students. When students think that they understand a concept, but really have some significant misconception lodged in their mental picture of the concept, they may not supplant this misconception for years, if ever. Both situations can be corrected if the students identify the need to ask questions, are brave enough to do so in the traditional academic settings, and if the answers adequately address the actual misunderstanding (which may be …


Application Of Mechanistic Models In Predicting Flow Behavior In Deviated Wells Under Ubd Conditions, Faisal Abdullah Aladwani Jan 2003

Application Of Mechanistic Models In Predicting Flow Behavior In Deviated Wells Under Ubd Conditions, Faisal Abdullah Aladwani

LSU Master's Theses

Underbalanced drilling (UBD) has increased in recent years because of the many advantages associated with it. These include increase in the rate of penetration and reduction of lost circulation and formation damage. Drilling of deviated and horizontal wells also increased since recovery can be improved from a horizontal or a deviated well. The drilling of deviated wells using UBD method will reduce several drilling related problems such as hole cleaning and formation damage. Prediction of flow and pressure profiles while drilling underbalanced in such wells will help in designing and planning of the well. The main aim of this research …


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 …


Low Salinity Flooding In A Selected Carbonate Reservoir: Experimental Approach, Mohamed Yehia Mohamed Mahmoud Jun 2002

Low Salinity Flooding In A Selected Carbonate Reservoir: Experimental Approach, Mohamed Yehia Mohamed Mahmoud

Theses

Low-salinity water flooding LoSalTM has been used to improve oil recovery for many decades. Historically, the mechanisms behind this improvement in oil recovery were attributed to the pressure maintenance and displacement of oil by injected water, i.e. physical mechanism. Recently, evidence from laboratory and field tests indicated that water flooding also involves chemical processes and that modifying of the injection brine salinity and its ionic composition can significantly impact the oil recovery. Several theories regarding the mechanism of LoSalTM flooding have been discussed in the literature. These include interfacial tension reduction, wettability alteration (cation exchange), change in pH …


Field Analyses Of Rdx And Tce In Groundwater During A Gcw Pilot Study, Andrew Curtis Elmore, Lisa A. Travaglin, Jennifer L. Triplett Jan 2002

Field Analyses Of Rdx And Tce In Groundwater During A Gcw Pilot Study, Andrew Curtis Elmore, Lisa A. Travaglin, Jennifer L. Triplett

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Contaminant concentrations in groundwater are typically analyzed using traditional laboratory analytical procedures approved by the Environmental Protection Agency (EPA) or state regulatory agencies. The use of off-site laboratories provides very high-quality water quality data at a relatively high cost in terms of time and money. Yet there are many instances when it is desirable to have water quality data measured in the field. The field methods for measuring water quality typically cost much less than the corresponding laboratory methods. However, the usability of the field data may be uncertain when the results are qualitatively compared to duplicate laboratory results. Groundwater …


Incorporation Of Cerium And Neodymium In A Uranyl Hydroxide Solid, Chang-Soo Kim, David J. Wronkiewicz, R. J. Finch, E. C. Buck Jan 2002

Incorporation Of Cerium And Neodymium In A Uranyl Hydroxide Solid, Chang-Soo Kim, David J. Wronkiewicz, R. J. Finch, E. C. Buck

Electrical and Computer Engineering Faculty Research & Creative Works

The migration behavior of radionuclides in a nuclear-waste repository will be influenced, in part, by their equilibrium solubilities in the presence of radionuclide-bearing solids and/or adsorption affinities as trace components onto the surfaces of solid host phases. Uranium phases that precipitate on the surface of altered spent nuclear fuel may thus influence the mobility of radionuclides released in the near-field environment, since by proximity, these will be the first phases that the radionuclides encounter following their release from the spent fuel matrix. We have evaluated the potential for incorporating radionuclides into crystalline compounds by precipitating uranyl phases from aqueous solutions …


Surfactant-Induced Relative Permeability Modifications For Oil Recovery Enhancement, Subhash C. Ayirala Jan 2002

Surfactant-Induced Relative Permeability Modifications For Oil Recovery Enhancement, Subhash C. Ayirala

LSU Master's Theses

Surfactants have been considered for enhanced oil recovery by reduced oil-water interfacial tension. However, these surfactants may enhance oil recovery via wettability alteration as well. This study experimentally determines the influence of surfactant type and concentration on oil recovery, oil-water relative permeabilities and wettability in reservoir rocks. Several coreflood experiments were conducted using Yates reservoir fluids in Berea rocks and two types of surfactants (nonionic and anionic) in varying concentrations. A coreflood simulator was used to calculate oil-water relative permeabilities by history matching recovery and pressure drop measured during the corefloods. These relative permeability variations were interpreted using Craig's rules-of-thumb …


Water-Drive Gas Reservoir: Sensitivity Analysis And Simplified Prediction, Junpeng Yue Jan 2002

Water-Drive Gas Reservoir: Sensitivity Analysis And Simplified Prediction, Junpeng Yue

LSU Master's Theses

Water influx and well completions affect recovery from water-drive gas reservoir. Material balance, aquifer models and well inflow equations are used to examine and predict the pressure depletion, water influx, and production rates of water-drive gas reservoirs. The parameters of these simple, lumped models are estimated from simulation results using response surfaces and experimental designs for eight varying geologic and engineering factors. Eleven simulated responses (including maximum gas rate, aquifer and well constants, and water breakthrough) are analyzed using ANOVA and response models. A sensitivity analysis of aquifer productivity index, gas production factor, and sweep efficiency reveals that permeability is …


Kekf R1 Reservoir - West Delta Block 84, Plaquemines Parish, Louisiana - An Analysis And Confirmation Of Bypassed Primary And Secondary Reserves, William Clay Kimbrell Jan 2002

Kekf R1 Reservoir - West Delta Block 84, Plaquemines Parish, Louisiana - An Analysis And Confirmation Of Bypassed Primary And Secondary Reserves, William Clay Kimbrell

LSU Master's Theses

West Delta Block 84 Field is located off the coast of Plaquemines Parish, Louisiana. The intent of this endeavor is to prove that the two of the reservoirs, the KE-1 and KF-1, form a single communicating reservoir, the KEKF-R1; that a waterflood into the KF-1 reservoir was ineffective; that oil reserves were bypassed; and that a portion of these bypassed oil reserves can be recovered without drilling new wells. Comparisons between pre-seismic and post-seismic geological interpretations were studied, a thorough volumetric analysis was performed with a subsequent material balance calculations and a reservoir computer simulation was performed. Once a history …


The Effects Of Rock And Fluids Characteristics On Reservoir Wettability, Chandra S. Vijapurapu Jan 2002

The Effects Of Rock And Fluids Characteristics On Reservoir Wettability, Chandra S. Vijapurapu

LSU Master's Theses

Wettability is the ability of a fluid to spread or adhere on a rock surface in the presence of other immiscible fluids. Knowledge of wettability is important to decide what production strategy needs to be employed for optimum oil recovery. Wettability is affected by rock mineralogy, rock surface roughness, and brine compositions. Previous studies have dealt with solid-liquid-vapor systems and those involving wettability characterization in solid-liquid-liquid systems have used contact angle techniques known to have reproducibility problems. In this study, a new technique called the Dual-Drop-Dual-Crystal (DDDC) Technique has been used to characterize wettability in terms of dynamic contact angles. …


Geostatistical Shale Models For A Deltaic Reservoir Analog: From 3d Gpr Data To 3d Flow Modeling, Hongmei Li Jan 2002

Geostatistical Shale Models For A Deltaic Reservoir Analog: From 3d Gpr Data To 3d Flow Modeling, Hongmei Li

LSU Master's Theses

The effects of shales on fluid flow in marine-influenced lower delta-plain distributary channel deposits are investigated using a three-dimensional ground-penetrating radar (GPR) data volume from the Cretaceous-age Ferron sandstone at Corbula Gulch in central Utah, USA. Using interpreted GPR data, we formulate a geostatistical model of the dimensions, orientations, and geometries of the internal structure from the subaerial exposure surface down to about 12 m depth. The correlation function between GPR instantaneous amplitude and shale index is built after statistical calibration of the GPR attributes (amplitude) with well data (gamma ray logs). Shale statistics are computed from this correlation function. …


Evaluation Of The Hydrocarbon Potential In Low-Salinity Shaly Sand, Fnu Kurniawan Jan 2002

Evaluation Of The Hydrocarbon Potential In Low-Salinity Shaly Sand, Fnu Kurniawan

LSU Master's Theses

This research utilizes reservoir data from an oilfield in Indonesia, which is characterized by shaly sand and low salinity formation water. Both low salinity and shaliness reduce the resistivity contrast between oil and water. The aim of this research was to build a comprehensive interpretation algorithm to evaluate the shaly-sand reservoir in a low salinity formation water using limited well log data. Shaly-sand interpretation is still evolving with numerous researchers conducting investigations of the clay minerals effect on rock conductivity through theoretical and experimental approach. These investigations can be loosely divided into either Fractional Shale Volume models or the Cation …


Remediation Of Trapped Free-Phase Lnapl, T. M. Whitworth, Andrew Curtis Elmore Jan 2002

Remediation Of Trapped Free-Phase Lnapl, T. M. Whitworth, Andrew Curtis Elmore

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Free-phase light nonaqueous phase liquids (LNAPLs) may be trapped in certain stratigraphic and structural features near or at contaminated sites due to seasonal or other variations in the water table elevation. The purpose of this article is to point out particular subsurface conditions that are conducive to trapping of free-phase LNAPLs and to suggest approaches to remediating LNAPL-contaminated sites exhibiting similar subsurface geometry and stratigraphy. To trap free-phase LNAPL, a structure must have, in addition to closed contours, an upper boundary with pores small enough so that the LNAPL will not enter them. This boundary usually consists of clay-rich sediments. …


Best Available Treatment Technologies Applied To Groundwater Circulation Wells, Andrew Curtis Elmore, Thomas Graff Jan 2002

Best Available Treatment Technologies Applied To Groundwater Circulation Wells, Andrew Curtis Elmore, Thomas Graff

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Groundwater circulation wells (GCWs) are a quasi-in-situ method for remediating groundwater in areas where remediation techniques that limit the water available for municipal, domestic, industrial, or agricultural purposes are inappropriate. The inherently resource-conservative nature of groundwater circulation wells is also philosophically appealing in today's culture, which is supportive of green technologies. Groundwater circulation wells involve the circulation of groundwater through a dual screen well, with treatment occurring between the screens. The wells are specifically designed so that one well screen draws in groundwater and the second returns the groundwater after it has been treated within the well. Historically, the treatment …


A Unified Theory On Residual Oil Saturation And Irreducible Water Saturation, Nick P. Valenti, R. M. Valenti, Leonard Koederitz Jan 2002

A Unified Theory On Residual Oil Saturation And Irreducible Water Saturation, Nick P. Valenti, R. M. Valenti, Leonard Koederitz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

In many mature fields, there is a growing debate as to how much of the remaining oil is mobile in the unswept regions versus immobile in the swept regions. Log measured oil saturations behind the flood front are substantially lower than the residual oil saturations measured from special core analysis. In order to explain this contradiction, data from several fields is analyzed with special emphasis on capillary pressure. The concept of irreducible water saturation, connate water saturation, residual oil saturation and "critical water saturation" are discussed. The conclusions which are supported by experiment and theory, have substantial commercial implications concerning …


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 …


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 …


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 …


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 …


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 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 …


Institutional And Other Constraints To Non-Oil Exports., R. O. Madaki Sep 2001

Institutional And Other Constraints To Non-Oil Exports., R. O. Madaki

Bullion

This paper examines the non-oil exports sector in Nigeria which had witnessed a lacklustre performance despite the several statements of government's interest in export-biased growth strategy and the establishment of several export facilitating institutions. The paper further observes that a major problem with Nigeria's non-oil export sector is that it is not predicated on the design and implementation of appropriate and coherent economic policies as there is no clear export promotion blue print in Nigeria. Consequently, the sector is facing a number of institutional and other domestic and external problems. The remaining part of the paper briefly highlight some of …


A Case Study Of The Beneficial Reuse Of Treated Groundwater, Andrew Curtis Elmore, Thomas Graff Jan 2001

A Case Study Of The Beneficial Reuse Of Treated Groundwater, Andrew Curtis Elmore, Thomas Graff

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The future disposal of treated groundwater at the former Nebraska Ordnance Plant (NOP) Superfund site has been a topic of interest to the local property owners, the U.S. Army Corps of Engineers, and the local regulatory agencies. The Record of Decision for the site includes the extraction, treatment, and disposal of almost 3,000 gpm of groundwater with an estimated restoration time period exceeding 100 years. Interest from property owners and the Nebraska agency charged with regulating groundwater supply prompted the Corps of Engineers to consider several strategies for beneficially reusing the treated water. Alternatives included the establishment of a rural …


Design And Installation Of Horizontal Wick Drains For Landslide Stabilization, Paul Michael Santi, C. Dale Elifrits, J. A. Liljegren Jan 2001

Design And Installation Of Horizontal Wick Drains For Landslide Stabilization, Paul Michael Santi, C. Dale Elifrits, J. A. Liljegren

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

One of the most effective options to stabilize landslides is to reduce the amount of water they contain by installing horizontal drains. A new type of horizontal drain material, geosynthetic wick drains, and a new installation method, driving drains rather than drilling them, were evaluated. Horizontal wick drains offer several advantages over conventional horizontal drains: They resist clogging, are inexpensive, may be deformed without rupture, and may be installed by unskilled laborers with a minimal investment in equipment. More than 100 drains were installed at eight sites in Missouri, Colorado, and Indiana using bulldozers, backhoes, and standard wick drain-driving cranes. …


Fourier Transform Raman Spectroscopy For Process Control In The Petroleum Industry, Kent Lawson Wise Oct 2000

Fourier Transform Raman Spectroscopy For Process Control In The Petroleum Industry, Kent Lawson Wise

Chemistry & Biochemistry Theses & Dissertations

As early as 1950, Raman spectroscopy was proposed as a method to determine aromatics and olefins in hydrocarbon mixtures. Until recently, extensive use of Raman spectroscopy in the characterization of hydrocarbons has not been practical due to several limitations. One early limitation to Raman analysis was the absence of a high intensity and stable excitation source. This problem has been overcome with the advent of lasers. Another limitation was the presence of fluorescence in hydrocarbon fuels when excited by visible lasers. However, the development of Fourier-transform Raman spectrometers now allows Raman spectra to be collected using near-IR lasers (e.g …


Simulation Of Temperature And Stress Fields During Rcc Dam Construction, Ronaldo Luna, Yongfu Wu Sep 2000

Simulation Of Temperature And Stress Fields During Rcc Dam Construction, Ronaldo Luna, Yongfu Wu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The worldwide experience in the construction of roller-compacted concrete (RCC) dams together with the use of numerical solutions, allows the simulation of different scenarios in a computer. It is well documented that thermal control is one of the most important problems for RCC dam construction. The dam temperature changes due to the heat produced by the internal hydration of concrete and the environmental boundary conditions influencing the elastic modulus and creep properties of concrete. The construction process was simulated to study how the temperature and stress change during dam construction. The numerical methodology considers the effect of temperature on the …


Development In The Petroleum Sub-Sector And Their Impacts On Nigerian Economy., I. P. Ojinnaka Jul 2000

Development In The Petroleum Sub-Sector And Their Impacts On Nigerian Economy., I. P. Ojinnaka

Bullion

The development of the petroleum industry has had both negative and positive impacts on the Nigerian economy. Two schools of thought can be examined. First, that positive impacts outweigh the negative, and secondly, the inverse. The paper will examined the impacts and analyzed the positive ones. From the approach of the study it is clear that the petroleum industry has had both negative and positive impacts on the Nigerian economy. Nigeria without petroleum could be like any other country without oil or gas, that is, import dependent. However, Nigeria with oil is the best thing that could have happened to …


Calibration Of Optical Digital Fragmentation Measuring Systems, Norbert H. Maerz, Wei Zhou Jun 2000

Calibration Of Optical Digital Fragmentation Measuring Systems, Norbert H. Maerz, Wei Zhou

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Optical granulometry systems like WipFrag are required to measure fragments in situ. That is to say, the fragments are in piles where sorting takes place, where fragments are partially overlapped, and where fines may not be seen because they fall in and behind the coarser fragments, or where the fines are simply too small to be seen. As a result, optical systems tend typically to overestimate the size of the distribution, and underestimate the variability of the distribution. The wider the size distribution being measured, the more severe the problem is. This paper presents the results of a study that …