bluuebunny/crossref_metadata_2025_split huggingface dataset:
Principles of Acid Stimulation
Authors: Muecke Thomas Wayne 
Published: December 2007

ABSTRACT
If properly designed and implemented, acid stimulation treatments provide a method for improving the productivity of oil and gas wells. The success of these treatments depends to a great extent upon proper acid selection and good treatment design. This can be accomplished only with a good understanding of the fundamental principles of acid stimulation. This paper reviews these important principles and includes descriptions of the basic concepts of damage removal, reservoir stimulation, acid reaction mechanisms, job design and diversion technology. Example field case histories are included to illustrate the benefits that can be derived from properly administered acid treatments.
Investigation of Well Damage Case History
Authors: Braunston R. J. 
Published: December 2007

ABSTRACT
Soon after start-up of the Prudhoe Bay Field in mid-1977, a number of wells with abnormal productivity decline were recognized. Research into the problem was undertaken as a coordinated effort of the Prudhoe Bay Unit Owners involving engineering, laboratory and geological studies concurrent with an extensive field work program. Investigations over the past three years have defined a major damage mechanism and efforts are continuing toward solutions for effective long-term production capacity maintenance.
Study of Reservoir Damage Produced in Heavy Oil Formations Due to Steam Injection
Authors: McCorriston Lois L. , Demby Richard A. , Pease Eric C. 
Published: December 2007

ABSTRACT
Steam injection in heavy oil reservoirs produces hydrothermal reactions which can lower producing potential by reducing permeability and causing well bore damage.
Effluents from once-through steam generators often have pH values above 12 due to the use of high bicarbonate surface waters as feeds. Injection of these high pH and low ionic strength waters causes expansion and dispersion of water-sensitive clays and solubilization of silica and aluminum minerals. The hydroxide and carbonate ions in the effluents react with magnesium, calcium and other salts in formation waters to form precipitates.
Laboratory experiments showed that these alkaline boiler effluents irreversibly reduced the permeability of cores (by up to 70%), dispersed clays and solubilized quartz sands.
In the field, large quantities of amorphous precipitates containing magnesium, calcium and aluminum as well as clays, micas and quartz grains were produced from two wells with low oil/steam ratios. The quartz grains showed substantial changes in surface morphology similar to those produced by quartz solubilization experiments in the laboratory.
To minimize reservoir damage, steam generator effluents with reduced pH and increased ionic strength are being injected at two field pilots.
New Technique for Analysis of Variable Rate or Slug Test
Authors: Soliman Mohamed Y. 
Published: December 2007

ABSTRACT
This paper presents a new and simple technique to analyze a variable rate and slug test. It considers the production rate as a continuous function of time and produces an equivalent Horner plot.
Two slug tests are analyzed comparing the new and various existing techniques. Existing techniques include type curve matching of flowing period, a multi-rate test, and the Odeh-Selig variable rate technique.
Determination of Oil Saturation Distributions in Field Cores By Microwave Spectroscopy
Authors: Brost Dale Francis , Davis Lorne Arthur 
Published: December 2007

ABSTRACT
Two microwave absorption spectrometers have been developed for routine monitoring of So distributions during laboratory flooding experiments in field core material. Operating frequencies are 10.525 and 24.125 GHz. Based upon low-power, mass-produced microwave components, these instruments are inexpensive, safe, very compact and rugged and require no special expertise for operation. A core sample cell has been designed which permits So distributions to be determined in narrow rectangular and cylindrical cores. An indirect calibration technique has been developed using the injection of aqueous solutions of 2-propanol to compensate for the porosity variations and irregular Soi and Sorw distributions inherent to segmented field cores. Details of the instrumentation are presented with a theoretical description of instrumental response. The practical utility of this instrumentation for the a priori detection of core defects and quantitative determination of porosity distributions is demonstrated.
Patterns of Wetting Behavior in Multicomponent Systems
Authors: Teletzke Gary F. , Scriven L. Edward , Davis H. Ted 
Published: December 2007

ABSTRACT
When the equilibrium states of two coexisting fluid phases lie sufficiently near a critical point, one of the near-critical fluids is prevented from contacting any given solid or third fluid phase by a wetting film of the other near-critical fluid. We classify the possible patterns of wetting behavior in systems of two and three fluid phases and show that the observed patterns for many systems, including equilibrated microemulsion systems, are consistent with this so-called critical-point wetting behavior. Implications for petroleum recovery are discussed.
Numerical Simulation of Heterogeneous Fractured Gas Reservoir Systems with Turbulence and Closure Stress Effects
Authors: Allam Awad M. , Crichlow Henry B. , Soliman Mohamed Y. 
Published: December 2007

ABSTRACT
A numerical technique for analyzing the behavior of a fractured gas reservoir system is presented. The reservoir is simulated by a fully implicit three-domensional model that incorporates the effects of turbulent flow and closure stress in a finite conductivity fracture. The model utilizes the real gas pseudo-pressure, two-point upstream transmissibilities and a stable iterative process based on a sparse matrix approach to solving the equation systems.
This paper presents a description of the model and applications to various reservoirs to illustrate the effects of fracture heights, turbulence and closure pressure on well performance.
Validity of Isochronal and Modified Isochronal Testing of Gas Wells
Authors: Mattar Louis , Lin Chung 
Published: December 2007

ABSTRACT
Combining the simplified analysis and the more rigorous Laminar Inertial Turbulent (LIT) analysis of isochronal and modified isochronal tests, it has been shown that these tests are valid, within engineering accuracy, for all values of the inverse slope, n. A sequence of increasing rates produces less errors in a modified isochronal test than decreasing rates. The Absolute Open Flow (AOF) calculated by the simplified analysis and that calculated by the LIT analysis, can be significantly different. A table of correction factors has been generated, which permits conversion of the AOF obtained from the simplified analysis to the value that corresponds to the more complicated LIT analysis. When the ratio of the AOF to the test rate is less than 3 the difference between the simplified AOF and the LIT AOF is less than 10%.
Pipeline Transportation of High Pour Handil Crude
Authors: Irani Cyrus A. , Zajac Jaro 
Published: December 2007

Abstract
Problems related with the pipeline transportation of high pour Handil (Indonesia) crude between Huntington Beach and Santa Fe Springs, California are discussed. The result of laboratory and field studies of chemical additives for pour depression are presented. A rotational viscometer was used to establish the relevant rheological parameters of treated and untreated crude. Chemical treatment at the 200 ppm level was found to be economically more attractive than the available heating step. A turnkey operation for additive injection available through a local commercial oil field chemicals supplier was implemented and continued for a period of two years. Recently a more economically viable heating step has been introduced to minimize the cost of pipeline transportation of Handil crude. A limited discussion is also presented of the use of analytical methods for improved characterization of the wax-wax and wax-additive interactions.
In-Situ Coal Gasification of Bituminous Coals – A Development Plan
Authors: Zielinski R. E. , Agarwal A. K. 
Published: December 2007

ABSTRACT
There are in excess of one trillion tons of bituminous coal resources in the United States, (1) Most of this resource is concentrated in the Appalachian, Illinois and Western Interior Basins. Approximately 220 billion tons of this bituminous resource, which is comparable to the estimated mineable reserves, can be recovered by Underground Coal Gasification (UCG). A technology that would provide for the economic production of gasoline and SNG in the eastern;, high energy use markets would provide an essentially new energy source to these markets. The high rank thin seam bituminous coals therefore provide an effective target for the development of a economically viable technology for resource recovery.
The only recent field test in these thin, seamed, high rank coals was the Pricetown I Field Test performed at Pricetown, West Virginia. This test demonstrated the feasibility of gasifying deep (~ 900 feet), thin seam (~ 8 feet), swelling bituminous coals. This test provided a 72% energy recovery by utilizing only air injection. While the test was successful in meeting all of its objectives, it was only the first step in the development of eastern UCG technology. The data obtained from the test can be used to develop an effective plan which can lead to a commercial demonstration and subsequently, commercial acceptance of this technology for bituminous coals by the 1990's.
To meet the requirements of a commercial demonstration, a three phase plan is proposed for the commercialization of this technology. Phase I of this plan addresses the issues still remaining in the swelling bituminous coals of the Appalachian Basin, whereas Phase II initiates the technology in the untested Illinois Basin and Phase III provides for a commercial demonstration in the Illinois Basin near existing energy markets.
Characterization of Porous Media Properties and Leaching Capacity of Spent Oil Shales
Authors: Ramirez W. Fred , Morelli Patrick T. 
Published: December 2007

ABSTRACT
Porous media properties of spent oil shales have been determined in order to provide fundamental data needed to identify and predict the transport of leachates through surface piles or abandoned modified in-situ retorts.
Using high pressure mercury porosirnetry, pore size distributions were measured. Results show unimodal pore size distributions. Mean pore sizes range from 5 microns for powders to 1 micron for compacted powder pellets to 0.5 microns for consolidated chunks.
Specific surface areas were measured using both the mercury intrusion technique as well as BET nitrogen adsorption. Both experimental techniques gave similar results implying the absence of micro pores.
Visual and chemical analyses were performed by scanning electron microscopy and x-ray fluorescence spectroscopy. SEM micrographs show the uniform pore properties of the spent shale samples as well as giving information on average grain sizes. All SEM micrographs indicate the existence of dead-space-volume.
Leaching capacities of the various spent shale samples were measured using equilibrium leaching studies to determine Equilibrium Exchange Isotherms. Some leachate species exhibit a smooth continuous release whereas other species show discontinuous jumps in the exchange isotherm owing to the encountering of solubility limits for specific chemical species.
Based on these spent shale characterization studies, fundamental modeling concepts have been established for the transport of leachates through spent oil shales.
Characteristics of Oil Displacements by Aqueous Surfactant Solutions
Authors: Minssieux L. , Moulu J. C. 
Published: December 2007

ABSTRACT
The aim of this laboratory work was a detailed study of oil recovery ability of aqueous surfactant solutions.
The first part included determination of relevant physical chemical properties of additive solutions, i. e. interfacial and rheological properties, phase diagram exploration as well as an evaluation of the specific adsorption-retention properties of surfactant polymer solutions in porous media used for oil recovery tests.
In the second part, the results of the series of oil displacements were analysed –to give a precise description of the main features of displacements by aqueous surfactant solutions,–to assess their oil recovery efficiency, shown to depend on surfactant concentration in slug injected, consecutive or simultaneous injection mode of polymer and surfactant and additive retention properties in the porous media chosen,–to compare the oil recovery performances of surfactant solutions and microemulsions taken from the same Winsor III type diagram.
Finally, application of a Buckley-Leverett type approach was considered to aid in the interpretation of the successive displacement steps observed during flooding by surfactant solutions at low or moderate concentrations.
Statistical Decline Curve Analysis
Authors: McNulty Robert R. , Knapp Roy M. 
Published: December 2007

ABSTRACT
The best hyperbolic curve is numerically fit to production decline data from selected oil wells. A non-linear optimization computer program finds the three best values of the general hyperbolic parameters q0, a, and b using least squares regression. By using weighted residuals, better history matching is obtained than with previous least squares methods. The future rate-time behavior of a well with only a few months of production is predicted by an analogy with other similar wells.
This production extrapolation method is superior to graphical or type curve procedures since it does not require engineering judgement until the unbiased curve fit has been calculated from observed production data. The program calculates consistent results based only on production values. Then, the evaluation engineer can use his judgement and experience to modify the prediction.
Response of the Dual Spacing Neutron Log (CNL) to Gas
Authors: Ullo J. J. 
Published: December 2007

ABSTRACT
The application of a mathematical model based on 2-dimensional transport theory to predict gas response characteristics of a new version of the CNL tool, called the CNL-G, is described.
It is well-known that when gas or light hydrocarbons are present in a formation the neutron log will indicate a low apparent porosity — lower in fact than what might be expected by taking account only of the lower hydrogen density. The cause for this difference has been called the excavation effect(1).
Calculations of the magnitude of the excavation effect are presented. In addition, the potential use of various combinations of neutron detector count rates as gas indicators is examined. Calculations suggest that these indicators may complement the traditional ϕdensity-ϕneutron gas signal in useful ways especially when deep invasion, very shaly sands, and thermal neutron absorbers weaken the traditional density-neutron diagnostic.
Facies Types and Reservoir Quality of the Rotliegendes Sandstone, North Sea
Authors: Robinson Alec E. 
Published: December 2007

ABSTRACT
A study of the Rotliegendes sandstone in part of Quadrant 47 in the southern U.K. North Sea showed that of three facies types, eolian dune sandstones have the best reservoir properties. Proximity to a fault also has a dramatic local effect on reservoir quality and productivity as shown by an example from Indefatigable Field.
New Technology Improves Economics in Canada's Extensive Alberta Oil-Sands Region
Authors: Nibogie R. , Buske R. , Overstreet J. , Dick J. 
Published: December 2007

Abstract
Long-term elevated oil price stability has caused operators to apply new, high-end technology to extract bitumen from Alberta's extensive oil sands deposits (174 billion recoverable bbls). In the Fort McMurray Area, operators are utilizing a Steam Assisted Gravity Drainage (SAGD) project to get the low-gravity (≤10° API) hydrocarbons to the surface. These wells are attractive because there is no exploration risk and they typically have a 30-50 year life with no decline curve.
The project requires drilling relatively shallow (500m–700m TVD) wells, but to an extended measured depth up to 3000m, through soft, yet extremely abrasive sands. The wells have high build-rates (9°/30m) and typically the horizontal section averages around 1000m but lengths can reach 2000m or more. To achieve the well profile and run-length requirements and withstand instantaneous ROP up to 200m/hr, operators were utilizing steel-tooth bits for the build sections and PDC to complete the horizontal legs.
To improve economics/footage drilled in the build section, a service company has developed a new 14-3/4" (374.6mm) rollercone bit with an innovative steel-tooth cutting structure that provides extended wear resistance for drilling in these highly abrasive SAGD directional applications.
The new bit features a thick application of highly wear-resistant hardfacing materials and new cone design increases gauge holding ability allowing multiple runs without going undergauge. Finally, a metal-seal provides extended bearing life by resisting accelerated wear due to the sharp abrasive sand formations. Because of the new technology, operators are getting more meterage utilizing the new steel-tooth abrasive bits compared with conventional premium milled tooth products. This allows the operator to drill up to four build sections with one new technology bit compared to only one or two hole sections with conventional bits, thereby cutting costs substantially.
Field Pilot Tests for Tertiary Recovery Using Butane and Propane Injection
Authors: Pacheco Edgar F. , Garcia Alfredo I. 
Published: December 2007

ABSTRACT
This paper describes a pilot project for tertiary recovery of liquid hydrocarbons through LPG injection in watered-out sections of the Bolivar reservoir in La Peña Field, Santa Cruz-Bolivia. The promising results obtained in the initial field misoibility tests, as well as the results from a mathematical model built to simulate and evaluate the tertiary recovery project, directed subsequent work into a cyclic scheme for enhanced recovery. This scheme is explained and injection production data is presented. Field facilities built to handle both the injected LPG and the produced Oil-LPG mixture are described. The Oil/LPG ratio and the LPG recovered/injected fraction are the main factors measured in this test to make further considerations for a full scale project.
The Role of Rock Mechanics in Optimizing Devonian Gas Production From the Appalachian Basin
Authors: Advani Sunder H. , Lee J. K. , Komar Charles A. 
Published: December 2007

ABSTRACT
The phenomenological theories of gas production, from a rock mechanics vantage point, are related to the characteristics of the natural fracture systems and their subsequent interaction with the induced fracturing. The dominant role of the in situ stresses and formation mechanical properties for reservoir site selection and hydraulic fracture treatment are quantified in this paper. An illustration of basement-sedimentary cover interaction and salient mechanisms responsible for stress reorientation and tectonic relief in the Rome trough region of the Appalachian Plateau is given. In addition, examples detailing induced fracture dimension evaluations along with a discussion of factors governing fracture width, vertical fracture migration and fracture length are presented. Finally, the suitability of different stimulation treatments is discussed.
Use of Electric Immersion Heating Elements In Oilfield Heater-Treaters
Authors: Palastak James E. 
Published: December 2007

ABSTRACT
With the depletion of gas reserves, the increase in commercial demand and the rising cost of natural gas, alternatives for a reliable, safe, economical and efficient method for preheating produced fluids in heater treaters is sought. A case history on the performance of an electric immersion heater versus a conventional gas firetube is presented under similar pumping and climatic conditions. The immersion heater uses the principle of resistive type of heating (thermal energy). Some advantages of using electric immersion heater's are: They help reduce the possibility of fire or explosion hazards since there are no open flames. Explosion-proof units are available if required.They eliminate all inconveniences created by the pilot light blowing out in a gas-fired vessel thus requiring the fluid to be rerun through the treater.By the removal of selected in-line fuses, the quantity of heat can easily be adjusted to the requirement of the job (from the minimum to maximum unit capacity), giving a flexibility that cannot be obtained from the gas fired unit.Existing gas-fired heater treaters can be easily retrofitted with an electric immersion heater.
The test showed the cost of electric heating to be directly competitive with the cost of gas treating in one of Amoco's operated West Texas fields. In areas where residue gas is sold for a higher price (over $0.50 per MCF), the fuel cost difference might strongly favor the electric heating element. The heating element would have immediate application in areas where treater gas has to be purchased from a utility or is not available at all, and in areas where it is impossible or undesirable to make daily checks of gas-fired treaters.
Electrical Submersible Pumps for the Montrose Field - Their Application and Post Operational Experience
Authors: Way A. R. , Hewett M. A. 
Published: December 2007

ABSTRACT
The North Sea Montrose Field has been on production since July 1976. Since mid 1979 artificial lift has been necessary on certain wells, due to their high water cuts.
This paper reviews the application of electrical submersible pumps for artificial lift on Montrose Field, the choice and sizing of equipment, completion design and the installation procedure. Problems encountered and post-appraisal of the electrical submersible pump installations, together with any changes made to remedy the problems and improve pump performance, are discussed. Specific items covered include the experience with rotary gas separators, the run life and performance of submersible pumps, and the economics of submersible pumps for artificial lift.
Submersible pumps have been used to maintain production which has decreased on certain wells in the Montrose Field due to increasing water cuts. The submersible pumps have been run in high angle holes (65°), at measured depths of approximately 10,000 ft., with production of high GOR (900 SCF/BBL) and in the presence of sand. The reservoir pressure is a maximum of 3000 psig and the reservoir temperature is 255°F. Experience gained by Amoco with submersible pumps in the offshore environment of the North Sea is applicable to other operators and their artificial lift requirements, especially where high production rates and hostile environments are encountered.
It has been shown to date that electrical submersible pumps can be run in the North Sea, but with only limited success. Advantages exhibited over gas lift (presently the only viable alternative to electrical submersible pumps in the North Sea), are the comparatively low initial installation costs and an application on a well by well basis, rather than a field wide basis; however, these advantages can only be achieved provided a satisfactory pump run life is obtained. A total of ten electrical submersible pumps have been installed on the Montrose Field, with an average run life of approximately four weeks, and a maximum run life of approximately three months.