bluuebunny/crossref_metadata_2025_split huggingface dataset:
Partial-Exclusion Sand Control Technique for Improving the Efficiency of Thermal Operations From Unconsolidated Heavy Oil Formations
Authors: Toma P. , King R. W. , Harris P. , Jha K. N. , Korpany G. 
Published: December 2007

ABSTRACT
A sand control device using prepacked metallic wool designed for total exclusion of sand in thermal operations was tested in Lloydminster and Athabasca unconsolidated sand formations. The results obtained from 20 different applications, which are summarized in this paper, indicate that sand production previously plaguing some locations disappeared after the new filter was introduced. However, high pressure drops and reduction in production rate were sometimes associated with partial plugging of the filter in fine grained formations.
As a result of the field observations, a laboratory investigation was undertaken to design new criteria for the prepacked metallic wool filter and to achieve better control of solids by using a partial filtration strategy. The experimental program presented in the paper includes a laboratory testing method which replicates open-hole completions. Alteration of filter permeability, including the formation of a filter cake in open-hole conditions, indicates that a different sand control strategy should be designed for set-through and open-hole completions. A filtration model based on laboratory experiments using a prepacked metallic wool filter for sand control in an open hole is suggested. The model assesses the risk of plugging as a function of formation median grain size, filter compression, and the grade of metallic fibers. The model provides practical criteria for designing a prepacked metallic wool filter for partial exclusion of sand and to avoid a rapid loss of filter permeability in fine-grained, unconsolidated formations.
Steam-Solvent Injection, Well LSJ-4057, Tia Juana Field, Western Venezuela
Authors: Bracho L. G. , Oquendo O. A. 
Published: December 2007

ABSTRACT
The purpose of this paper is to present the results obtained in the well LSJ-4057, Tia Juana field, Western Venezuela, by injecting steam and solvent simultaneously.
According to laboratory tests, industrial diesel, which is considered a medium weight solvent, showed to be the most compatible with the crude produced in the area, and because of its availability and lower cost, it was selected for the pilot test.
During this pilot test, which corresponded to the second cycle of steam injection of the well, a total of 31.5 MSTB [5 015 stocktank m3] of steam (cold water equivalent) was injected with 1876 STB [298 stock-tank m3] of solvent, in a 3-stage injection procedure.
The average initial production was 301 B/D [47.8 m3/D], resulting 63.6% higher than the average initial production rate for second cycle wells in the same area. Also, the cumulative production for a 30-month period was 85.9% higher than that of neighboring wells.
These results suggest the potentiality of this technique to increase the final recovery of oil by cyclic steam injection in heavy oil reservoirs.
Hot-Water and Steamflood Studies Using Kern River Oil
Authors: Bousaid I. S. 
Published: December 2007

ABSTRACT
This paper presents the results of hot-water and steamfloods conducted in a five-foot linear cell. The effect of injection rate of 240°F water and steam was studied for the Kern River viscous oil (13°API) using a fine graded silica sand.
Temperature profiles along the sandpack were used to relate changes in oil saturation with temperature effects. An increase in the water rate resulted in higher temperature profile and minimum Sorw values obtained near the sandface. The results were used for determining the optimum temperature for mobilizing and effectively banking Kern River oil by hot-water floods. A correlation was obtained relating final Sorw values to the oil/water viscosity ratio, thus removing the temperature dependency for the viscous oil (6800 cp @ 80°F).
The steam rate was varied between tests to observe its effect on the steamflood recovery process. The oil and temperature response at the production end was related to the steam fronted advance along the sandpack. The oil response and recovery at steam breakthrough increased with increase in the steam rate. The opposite effect was obtained after breakthrough. The frontal velocity to steam and gas saturation in the steam zone varied with the steam rate. The study evaluates the effect of steam rate on frontal advance, oil banking process, oil recovery, and production to injection ratio as a function of a dimensionless time factor based on steam breakthrough.
Mount Poso Upper Vedder Simulation Study
Authors: Iyican L. M. 
Published: December 2007

ABSTRACT
The Upper Vedder sand is the main productive horizon in Mount Poso, a heavy oil field in San Joaquin Valley, California. It is a homogeneous sand with very high porosity, permeability, and N/G ratio. Following 45 years of primary production, a very successful steam drive has been in operation since 1971. This line drive thermal development with updip steam injection is now at its final stages. The purpose of the simulation study is to determine the changes in operating policy to optimize financial performance. The study consists of developing a numerical reservoir simulation model, calibrating the model, testing various operating scenarios, and making recommendations. The recommendations include a series of steam cuts, steam injector moves, and increased aquifer withdrawals. These recommendations are currently being implemented. Results to date are also discussed.
Transient Pressure Analysis In Partially-Penetrating Wells
Authors: Yildiz Turhan , Bassiouni Zaki 
Published: December 2007

Abstract
A new mathematical model is developed to predict the transient pressure behavior of a partially-penetrating well (PPW). The model is derived by solving the two-dimensional (2-D) diffusivity equation. The Laplace transformation and the separation of variables technique are used. A convolution technique is used to incorporate the well bore storage and skin factor. The solution has the form of the infinite Fourier-Bessel series and can be easily implemented using a personal computer.
Using the new model, the pressure behavior of a PPW is analyzed, and the approach of current interpretation techniques is investigated. Currently, it is claimed that a plot of pressure vs log (time) displays an early- and a late-time straight line. It has also been assumed that there is a spherical flow period between the early-time and late-time radial flow regimes. This investigation shows that there is neither early-time straight line nor spherical flow period. What may appear to be a straight line on these plots is merely the result of an inflection point. Therefore, the interpretation techniques based on the existence of an early-time radial flow period and spherical flow in the transition period are questionable. Further study has also shown that the type-curve matching methods provide a non-unique solution.
Pressure-derivative and pressure-integral behavior of a PPW are also examined. Derivative and integral type curves were constructed, and their ability to interpret the test data is investigated.
A new interpretation technique is proposed to alleviate the short-comings of existing methods. The new method provides unique solutions to horizontal and vertical permeabilities and skin effect. The method is based on the deconvolution of measured pressure and flow rate data. The limitations of the proposed interpretation technique are also outlined.
Laboratory Study Provides Guidelines for Selecting Clay Stabilizers
Authors: Crowe Curtis W. 
Published: December 2007

Abstract
Various clay stabilizers are discussed, and methods are proposed for evaluating their effectiveness. Laboratory tests are used to rate the relative efficiency of potassium chloride vs other salts and organic compounds. Advantages and limitations of the various clay stabilizers are described. These studies show that increased temperature improves the efficiency of KCI and that pH is not a significant factor, except in low-salinity solutions. Alternate materials are sometimes superior to KCI, but care must be taken when using substitute products.
A Unified Treatment of Material-Balance Computations
Authors: Vo Dyong T. , Jones Jack R. , Camacho-V. Rodolfo G. , Raghavan Rajagopal 
Published: December 2007

Abstract
A unified treatment of materials balance computations to estimate hydrocarbons in place is presented. This method generalizes the normal procedures for gas reservoirs to all fluids of interest to the petroleum industry. We show that a plot of average pressure divided by a two-phase deviation factor can be used to compute hydrocarbons in-place. A simple procedure to estimate the required two-phase deviation factors for black oils and volatile oils is discussed. This extends the method of Vo et al. for gas condensates to these other systems. We concluded, in particular, that data above the phase envelope (single phase information) can be extrapolated and combined with data inside the phase envelop (two-phase information) to obtain initial hydrocarbons in place. The need for accurate fluid property description is emphasized and potential information that is obtainable from accurate fluid descriptions is noted. It is shown that data above the phase envelope can be extrapolated to obtain initial hydrocarbons in place.
An Improved Model for the Development and Analysis of Partial-Water Drive Oil Reservoirs
Authors: Saleh Saad T. 
Published: December 2007

ABSTRACT
In recent years, the use of numerical reservoir simulation to predict reservoir's future performance has shown a steady and strong increase. For meaningful result, however, reservoir simulation requires an extensive amount of data. In addition, many months of time is generally required to assemble and collect the data. Therefore, reservoir simulation is often impractical for small fields.
This paper presents the development and results of a comprehensive and rigorous material balance mathematical model which simulate an oil reservoir bounded by a gas-cap and a finite aquifer. The model incorporates the dynamics of oil/water and gas/oil contacts movements within a hypothetical cone-shaped, radial reservoir geometry. The basic components in the model are the material balance equation, water-influx model, a model for tracking the oil/water contact position, and a model for tracking the gas/oil contact.
The model was used to study the phenomenon of "late-water drive" which is an apparent increase in the activity of water influx in the late part of reservoir's life. The study concluded that the "late-water drive" phenomenon is caused primarily by the expansion of trapped gas behind the advancing oil/water contact. The study showed that even small aquifers (aquifer-to-reservoir radii ratio Ra/Ro &lt; 3) demonstrated strong water influx activity in the late part of reservoir's life. This behavior is often misinterpreted as an influx from a large aquifer.
This paper presents the results of a sensitivity analysis of the effect of aquifer size, gas-cap size, reservoir's permeability, etc on the movements of all fluid contacts in particular and reservoir performance in general. In addition, it was demonstrated that average reservoir pressure must be corrected to the original oil/water contact (commonly not done in conventional reservoir analysis studies) in order to correctly calculate water influx. The procedure of pressure correction is given with many examples of reservoir's performance prediction with and without pressure correction.
Improving Oil Recovery in the Naturally Fractured, Tight, Dirty Sandstone of the Townsend Newcastle Sand Unit - Weston County, Wyoming
Authors: Hochanadel Steven M. , Townsend Charles L. 
Published: December 2007

ABSTRACTThis paper summarizes the waterflood performance of the Townsend Newcastle Sand Unit (TNSU). Production is from the Muddy Newcastle sandstone located in the Powder River Basin of northeastern Wyoming. The field was discovered in June, 1960 and was depleted under solution gas drive to recover 13.0% of the original oil-in-place (OOIP) of 2.8 million STBO.Waterflooding the TNSU faced three obstacles; first, the reservoir is naturally fractured; second, the reservoir contains clays which can swell and migrate to reduce injection rates; and third, the matrix rock is heterogeneous and low in permeability (40 md average).A process approach was taken to overcome these adverse waterflooding conditions. First, the injection wells were pretreated with potassium hydroxide to permanently stabilize the clays. Then, cationic and anionic polyacrylamides and aluminum citrate crosslinker were injected to reduce flow through the factures as well as through any high permeability channels in the matrix rock. This was followed by a blend of phosphates and anionic polymer to maximize imbibition.The flood began in May, 1986. Oil production went from 3 BOPD prior to injection to a peak flood rate of 343 BOPD in November. 1988. Ultimate recovery is now projected to be 29.8% OOIP. Without the use of this process technology it is doubtful the field could have been economically flooded.
Use of Conventional Reservoir Models for Coalbed Methane Simulation
Authors: Seidle John P. , Arri Luis E. 
Published: December 2007

ABSTRACT
The recovery of gas from coalbeds is a two-step process. First, the gas diffuses through the matrix then, secondly, it flows through the cleats to the wellbore. If the release of gas from the matrix to the cleats is very rapid compared to the flow of gas and water in the cleats, the desorption kinetics are relatively unimportant in modeling coalbed methane production. If the coal is well cleated, it can be assumed for engineering purposes that the gas desorbs instantaneously from the matrix to the cleat when the pressure in the cleat decreases. This assumption allows the adsorption of gas on the surface of the coal to be modeled as gas dissolved in an immobile oil. Conventional reservoir simulators can then be used for coal bed methane modeling purposes. The solution gas-oil ratio of this immobile "pseudo" oil is calculated from the Langmuir adsorption isotherm constants and coalbed properties. Additional modest modifications are required in the data describing the porosity and gas-water relative permeability curves to account for the presence of the "pseudo" oil. No code modification is required. This concept has been used with several different simulators to successfully model both single well and 3-D, multiwell coalbed methane problems. A coal well simulation using this method and COMETPC, a simulator developed by ICF-Lewin, are compared.
Foamed Gas Lift
Authors: Bernadiner M. G. 
Published: December 2007

Abstract
Gas lift, a broadly applied method for producing oil, consists of gas injection into production wells to reduce the liquid density in the wells and increase the liquid inflow. Gas lift technology requires large gas volumes to be injected. If the reservoir pressure is depleted, the effectiveness of gas lift is dramatically reduced. To increase effectiveness and to extend gas lift applications to producing oil from depleted reservoirs, a foamed gas lift method has been investigated in laboratory and oilfield experiments. The method consists of foaming agent injection into a gas-liquid flow.
A laboratory set-up based on scaling parameters was used to study the productivity of the gas lift well exploiting the drainage area of the well. The laboratory experiments were performed over a wide range of the scaling parameter, describing the reservoir pressure depletion, with and without foaming agent. The results show that foamed gas lift would be efficient, especially if the gas lift well cannot produce without the addition of foaming agent. Analysis of the gas-liquid flow structure inside a vertical tube displayed the conditions of effective application of the foaming agent to improve gas lift technology. Oilfield experiments analyzed with probability theory corroborated that foamed gas lift is a very effective technological method if the reservoir is depleted
Improved Fracturing Techniques Increase Productivity in the AWP (Olmos) Field
Authors: Peard N. S. , Macaluso M. L. , Griffin M. C. , Andreas R. , Callanan M. J. 
Published: December 2007

Abstract
Early fracture treatments in the AWP (Olmos) field utilized over 1,000,000 lbs. of 20/40 mesh Ottawa sand. While production results were good, mechanical problems and economic factors necessitated alternative treatments. Smaller volume schedules were tried, but the resulting production lagged the larger jobs. Recently, treatments designed with resin coated sand (RCS) improved well performance. The stronger RCS maintains better conductivity at lower proppant concentrations with resultant good production response at a lower total cost. As an additional benefit, the curable RCS bonds together to eliminate proppant flowback.
Radial Modeling of In-Situ Gelation in Porous Media
Authors: Todd B. J. , Willhite G. P. , Green D. W. 
Published: December 2007

Abstract
A new radial model of in situ gelation of Polyacrylamide by Cr(III) produced by a redox reaction has been developed based on reaction kinetics describing the crosslinking and aggregation in the gelling solution, coupled with filtration equations governing the deposition of polymer on the porous medium. The gel system is based on the reaction of Cr(VI) with thiourea to produce Cr (III). Gelation occurs when Cr (III) reacts with Polyacrylamide. The radial model is an extension of a linear displacement model (SPE 20215). The linear model was tested against displacement data and matching parameters in the model were determined by regression. These parameters were then used in the radial model to simulate cases of practical importance.
The radial model describes gelation behavior during the period of gel solution injection and the subsequent shut-in period. During the injection phase, a buildup of flow resistance occurs in the presence of radial flow, i.e., a variable shear field. After shut-in, continued reaction of the gelling solution is simulated under conditions of zero shear. These features allow simulation of a complete gelation treatment from the injection phase through the shut-in period. Using this model, ranges of injection rates, pH, and injection and shut-in times are investigated. The pH history of the gel solution was found to be an important variable in the gelation process. If reservoir pH is in the vicinity of 8.0, gelation is retarded and long shut-in periods are required to develop adequate gel properties for permeability modification. The effects of reservoir pH can be offset by increasing the pH and the concentration of the reducing agent in the gel solution.
A simulation of a three-layer system maintained at constant pressure drop was conducted to illustrate the capability of the model. Permeabilities of the three layers varied from 0.035 to 3.5 darcies. For the gel system simulated, all layers became plugged to some extent during the injection phase. Depth of gel penetration was dependent upon the permeability of the interval. In the lowest permeability zone, the affected region was within the range where remedial treatment after gelation might remove the gelled zone. These results suggest that isolation of high permeability zones is required for in-depth permeability modification using the gel system examined in this study.
A Case Study of Plastic Plugbacks on Gravel Packed Wells in the Gulf of Mexico
Authors: Rice R. T. 
Published: December 2007

Abstract
A high success rate of water reduction has been documented in 21 plugback jobs performed on gravel packed wells in the Gulf of Mexico. This electric wireline plugback method was first introduced by Carroll and Bullen1 (SPE 18228) at the 1988 SPE Technical Conference in Houston. The plugback method is unique in that it is performed within gravel pack assemblies and utilizes plastic instead of cement.
This paper is a case study on actual field results for the 21 jobs performed by Tenneco/Chevron since the introduction of this method.
Fluid Mechanical Analysis for Control of Gravel Pack Jobs
Authors: Harestad K. , Saasen A. , Sterri N. 
Published: December 2007

Abstract
This paper presents an analysis of the pump pressure while pumping gravel pack slurry down into the well. Five field cases from the Troll field in the North Sea are evaluated. The rheological behaviour of the prepad and gravel pack slurries have been investigated. The pump pressures have been simulated by fluid mechanical analysis and are compared with measured values.
The Prediction of Operating Conditions to Constrain Sand Production from a Gas Well
Authors: Wang Zhihua , Peden J. M. , Damasena E. S. H. 
Published: December 2007

Abstract
This paper presents an analytical model for predicting the sanding tendency of a gas well. The onset of sand production in a cased well may result from the failure of the perforation tunnel to withstand both the in-situ stress and the flow/production induced stresses. The failure conditions of a cylindrical perforation tunnel subject to single phase gas flow in a friable sandstone formation, have been studied using elastoplastic stress analysis. The failure criterion employed in this paper is the critical equivalent plastic strain, which is the maximum plastic strain that can be sustained without failure and consequent sand production.
The effects of various production conditions have been evaluated by considering the pore pressure distribution associated with the production of gas. The results demonstrate that the flow of gas in the perforation tunnel tends to increase the instability, however compared to standard Darcy flow conditions, the inclusion of the non-Darcy flow effect due to high production rate, will significantly increase the instability. The effect on stability of the tunnel geometry, rock deformation and strength have been studied to assist in the evaluation of the influence of perforation geometry, in terms of shot density and phasing, on sand instability. The results show that an optimum perforation geometry requires a compromise between the productivity ratio and cavity stability.
The results obtained by running the model against a North Sea gas reservoir demonstrate that the model is a useful tool for designing sand free production completions or alternatively assessing the sensitivity of the sanding tendency to operational parameters.
Cement Expansion: A Laboratory Investigation
Authors: Moran L. K. , Murray T. R. , Moyer W. R. 
Published: December 2007

ABSTRACT
A cement which expands (or at least does not contract) under down-hole conditions can prevent microannular flow and can make bond log interpretation easier.
A comprehensive laboratory investigation of cement expansion using the most common cement expansion additives, calcium sulfate and sodium sulfate, was performed. Four API classes of cement were investigated from 75° to 200°F at pressures from atmospheric to 5000 psi. The slurries were cured in air, water, oil, and 100 percent humidity environments. The cements were mixed with three water contents. The expansion measurements were taken for ten days. The expansion measurements were of the type which measure the exterior dimensions of a cement sample as it cures.
The various curing environments are meant to simulate the curing environments experienced downhole. For instance, wells drilled with oil base mud would leave the wellbore area inundated with oil and thus the cement would be exposed to oil and not water during the curing period.
Several new additives for cement expansion have recently been introduced from the cementing service companies. Now that a thorough background study on existing materials has been completed, new materials can be more easily evaluated.