bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Practical Analytical Model for Geothermal Reservoirs Simulation
Authors: Castanier Louis M. , Sanyal Subir K. , Brigham William E. 
Published: December 2007

ABSTRACT
This paper describes the theory and algorithm for a practical, analytical model for simulation of geothermal reservoirs. The model can be applied to any type of geothermal reservoir: all liquid, all steam, or two-phase. The model assumes radial geometry with three distinct zones: (1) an innermost, circular production zone; (2) an intermediate, concentric zone subjected to fluid flow and heat transfer but no production or injection; and (3) an outermost, radially infinite (or finite) aquifer zone. The reservoir is assumed to be producing from the innermost zone, as dictated by the capacity of a power plant. The innermost zone is treated as a tank from the viewpoint of mass and energy production, using a lumped-parameter model, but one in which the pressure distribution is calculated by an analytical formulation of pressure behavior of off-centered wells enclosed in a constant pressure boundary circle. The surrounding intermediate zone from which fluids migrate into the production zone is assumed to have a radial temperature profile, T(r), depending upon the reservoir. This profile can be either continuous or a step profile. The injection occurs in the outermost zone and induces a flow of fluid from the outermost zone through the middle zone into the central tank. There is no constraint on the relative size of various zones. Injection in the central production zone (such as in a five-spot development) is possible. If there is no injection, natural transient water influx from the aquifer is considered.
For a given step of depletion in the tank model, mass and energy produced are calculated and the pressure distribution in the central part of the reservoir is computed. The mass of fluid injected and/or natural water influx from the aquifer zone is estimated, and corresponding fluid flow from the intermediate zone into the central zone is calculated. The new temperature profile in the intermediate zone is then computed, and the average enthalpy of the influx water into the central zone is then estimated. The average temperature and pressure in the central zone are then calculated and a new step of depletion is initiated using the lumped-parameter model. If either constant enthalpy or constant available work is the specified constraint on production, an iterative approach is used to assure satisfaction of the constraint. This process is continued until the abandonment temperature or pressure is reached.
Application of this model to the East-Mesa reservoir shows a reasonable agreement with the more complex simulations done with an Intercomp model by Republic Geothermal, Inc. A sensitivity study of this reservoir has been made.
Construction of Grounded Ice Island for Drilling in Beaufort Sea, Alaska
Authors: Brinker Tyler 
Published: December 2007

ABSTRACT
An exploratory well was drilled by Union Oil Company of California from a grounded ice island constructed in the Beaufort Sea. The ice island was 60 km west of Prudhoe Bay, Alaska, 3 km offshore, in 3 m of water.
Operations commenced in November, 1976, and terminated in April 1977. Project cost was $8 000 000. The ice island melted by mid July, 1977.
Grounded ice islands can be used in arctic areas of shallow water and little pack ice movement. They are environmentally acceptable and economically feasible.
A Laboratory Investigation of Enhanced Recovery of Methane from Coal by Carbon Dioxide Injection
Authors: Fulton Paul F. , Parente Carol A. , Rogers Bruce A. , Shah Nitin , Reznik A. A. 
Published: December 2007

Abstract
An experimental procedure for determining the effectiveness of CO2 injection into methane-containing coal samples for the purpose of enhancing methane production is described. Experimental results on both dry and water saturated samples reveal that CO2 injection greatly enhances both production rate and recovery efficiency. Most effective is a cyclic CO2 injection-gas production technique which recovered essentially all of the adsorbed methane in the 3½″ core samples used in the experiments.
A Wireline Hydraulic Fracturing Tool for the Determination of in Situ Stress Contrasts
Authors: Voegele Michael D. , Jones Arfon H. 
Published: December 2007

Abstract
A significant amount of research has been devoted in the past few years to the study of fracture containment in stimulation of low permeability gas reservoirs. One finding of this research is that vertical fracture growth is controlled by contrasts in the in situ stress state. A knowledge of the variation of horizontal stress with depth would aid in the design of well stimulation.
The only method available today for determining in situ stress at depths greater than about 200 meters is a small scale hydraulic fracturing technique; stress calculations are based upon several relatively simple measurements; however, at present the economics of sending the tool downhole on a tubing string are unfavorable. To overcome this problem the design of a self contained tool which operates on a standard seven conductor wireline cable has been undertaken by Terra Tek, Inc.; funding is being provided by the U. S. Department of Energy, Morgantown Energy Technology Center. A major goal of the design effort is to build the tool primarily with commercially available components. The basic tool consists of a downhole hydraulic power supply control unit, straddle packers and pressure transducer; it has been designed to function in cased or open holes. Additionally, the tool design incorporates a fracture detection device so that orientation can be determined.
In conjunction with the tool design a laboratory investigation utilizing 1 meter cubic samples is being pursued to study the mechanics of stress determination in cased boreholes. Since there is very little published literature on the determination of in situ stresses through perforated casing, it is hoped that the laboratory investigations will allow stress determinations in cased wells with the same degree of reliability that now exists for stress determinations in open holes.
Second Generation Technology for the Production of Pipeline Quality Gas from Sanitary Landfills
Authors: Rice Frederick C. 
Published: December 2007

Abstract
With the advent of replacement energy cost pricing for natural gas, the recovery and treatment of methane generated by sanitary landfills has become a commercial reality. The first landfill methane recovery plant, owned and operated by Getty Synthetic Fuels, Inc., has been in operation at Palos Verdes, California since 1975. Getty has built a second plant, which has been in operation in the city of Monterey Park, California since August 15, 1979. These two facilities are the only plants in the United States which produce pipeline quality gas from landfills.
Although similar to the Palos Verdes facility in some respects, the Monterey Park methane recovery facility is four times as large, and represents a significant advance in the State of the Art of landfill methane recovery and purification. This paper will discuss the similarities between these two operations, but, more importantly, will point out the significant technological advances made over the past four years, which have advanced landfill methane recovery from the demonstration project phase to the large scale, economically viable operation that it is today.
Completion Techniques and Production Data from Vertical Methane Drainage Boreholes, Jawbone Coalbed, Dickenson County, Virginia
Authors: Steidl Peter F. , Trevits Michael A. , Diamond William P. 
Published: December 2007

ABSTRACT
Five vertical methane drainage boreholes have been completed in the Jawbone coalbed at the Clinch-field Coal Co. McClure No. 1 mine in Dickenson County, Va. Foam stimulation treatments were used to increase gas production from the boreholes. After 15 months the cumulative gas production from the first hole was 310,000 cu m (11 MMcf) with production averaging 700 cu m/d (25.000 cu ft/d).
Advance Methane Control and its Impact on Gas Emissions in the Pocahontas #3 Coal Seam
Authors: von Schonfeldt Hilmar A. , Pothini B. R. , Aul George N. 
Published: December 2007

ABSTRACT
Methane emissions into underground coal mines in certain areas of the United States represent a serious hazard and contribute to lowering mining productivity. In order to reduce methane emissions into some of the deep south west Virginia Coal Mines an advance methane drainage program was developed. This paper gives a state of the art account of drilling long in-seam and slant holes into virgin areas of the Pocahontas #3 and #4 coalbeds. Directional drilling techniques are discussed. Methods to evaluate the drainage effectiveness of this program on the emissions in an operating mine are also covered. It is concluded that an effective methane drainage program can reduce methane emissions significantly thereby improving safety conditions in the mine. It also has the potential for increasing mining productivity. The recovered gas could also lead to a better utilization of our available energy resources.
Analysis of the Coalbed Degasification Process at a Seventeen Well Pattern in the Warrior Basin of Alabama
Authors: Ancell K. L. , Lambert S. , Johnson F. S. 
Published: December 2007

ABSTRACT
This paper presents an analysis of the coalbed degasification process. The theoretical and experimental basis of the degasification process are discussed and a simulation model which incorporates all aspects of this process is described. The simulator is demonstrated using actual field data developed by a joint industry/government demonstration project funded by the DOE and U. S. Steel. The basic reservoir description is discussed in detail, including variations of important description parameters with location.
Initial and boundary conditions are demonstrated and analyzed. Initially, the coalbed was saturated with water. With water production, reservoir pressure is lowered, causing gas to desorb from the coal creating a mobile gas saturation. Subsequently, interwell interference effects are demonstrated and the need for such effects explained.
Finally, the long term gas deliverability of the pattern is forecast. This forecast shows that about 45% of the gas within the pattern can be removed if the pattern is in operation six years ahead of mining.
Seismic Velocity Analysis to Locate Shale Gas Wells
Authors: Boyer John St. A. , Anstey Nigel A. 
Published: December 2007

ABSTRACT
It is known that economic production of shale gas is currently possible only where shale is naturally fractured. The exploration problem is therefore to locate zones of fracture. In principle, extenstive zones of natural fracture in a thick shale can be identified by the measurement of seismic velocity from the surface. The technique of reflection velocity analysis uses differential reflection time of reflections observed at the surface (with various source-geophone distances) to infer the extent of the gas saturated fracture zones. This technique has been applied along an available seismic line in Southeastern Ohio. A continuous velocity analysis of the shale interval along this line was prepared, and areas of depressed velocity have been identified. These results, and the results of drilling in the first area of low velocity will be discussed.
Recent Results On The Use Of Polymers In Tertiary Oil Recovery In Brines Of High Salinity
Authors: Lange Werner , Rehage Gunther 
Published: December 2007

ABSTRACT
By means of viscosity measurements at low shear rates (0.1 to 10 s−1) a great number of commercial polymer samples were tested. We succeeded in finding a few polymers which have a viscosity high enough for polymer flooding (&gt;20 mPa⋅s) at a polymer concentration of 800 ppm, even in a brine of high salinity (salt content 200 g/l). In additional filtration tests some of the selected products with sufficient viscosity values showed good results. Measurements of elastic and viscous properties indicated that some of the promising polymer solutions have pronounced elastic properties even at relatively low concentrations. As the elastic properties reduce the mobility ratio of the system oil-polymer solution, there should be an increase of oil recovery as the elastic properties of the polymer solution increase.
The Effect Of Alcohol On Surfactant Mass Transfer Across The Oil/Brine Interface And Related Phenomena
Authors: Chiang Michael Y. , Shah Dinesh O. 
Published: December 2007

ABSTRACT
The effect of alcohol on surfactant mass transfer from bulk solution to the oil/dilute tnicellar solution interface was studied. Various interfacial properties of the surfactant solutions and their ability for displacing oil were determined. For the surfactant-oil-brine systems studied, the interfacial tension (IFT) and surfactant partition coefficient did not change when isobutanol was added to the following systems: 0.1% TRS 10–410 in 1.5% NaCl vs n-dodecane and 0.05% TRS 10–80 in 1.0% NaCl vs n-octane. On the other hand, the interfacial viscosity, oil drop flattening time (i.e. the time required for an oil droplet to flatten out after being deposited on the underside of a polished quartz plate submerged in the micellar solution) and oil displacement efficiency were influenced markedly by the addition of alcohol.
In the presence of isobutanol, the oil/dilute micellar solution interface became more fluid and the flattening time decreased from 90 seconds to less than a second or 420 seconds to less than a second, and the final oil saturation decreased from 30% to 5.36% and 11.73% to 1.28% respectively for the two systems mentioned above. Furthermore, it was observed that after the arrival of the oil bank, the ΔP leveled off for the isobutanol containing systems, whereas it continuously increased for the systems without isobutanol. This observation is consistent with the proposed role of alcohol in lowering the interfacial viscosity and promoting coalescence of oil ganglia in porous media.
The flattening time was strikingly lower for the surfactant + alcohol system as compared to the flattening times in the presence of the surfactant or alcohol alone in the brine, suggesting that the rate of achieving ultra low IFT at the oil/micellar solution interface is strikingly enhanced by the presence of isobutanol resulting in greater oil recovery.
In order to delineate the effect of surfactant mass transfer on in situ behavior of oil ganglia, we carried out several oil displacement experiments using equilibrated and nonequilibrated oil/micellar solution systems. For equilibrated systems, the oil displacement efficiency showed an excellent correlation with IFT and capillary number. However, for unequilibrated systems, the oil displacement efficiency depended on salinity. Below optimal salinity, the oil displacement efficiency almost remained the same for both equilibrated and nonequilibrated systems, whereas at and above optimal salinity the oil displacement efficiency was higher for non-equilibrated systems as compared to equilibrated systems. This was attributed to mass transfer rate effects in these systems. Both sand packs-and Berea cores gave similar results. The results of this study demonstrate the importance of transient phenomena at oil/dilute micellar solution interface for oil displacement process with emphasis on the effect of alcohol and salinity.
Produced Fluid Changes During A Fireflood
Authors: Fulford Richard S. 
Published: December 2007

ABSTRACT
The Cities Service-U.S. DOE Bodcau In-Situ Combustion Project in Bellevue Field, Bossier Parish, Louisiana, has been in progress since 1976. During this fireflood, oil, gas and water produced at 37 wells were analyzed five times to measure changes in the fluids resulting from the fireflood. One analysis was done during the dry burn phase of the project and four were done during the simultaneous water-air injection phase. Temperatures as high as 800°C are reached in the dry burn phase and as high as 550°C in the wet combustion phase. Burning of coke and oil at these high temperatures results in complicated chemical and physical changes of the fluids.
Hydrothermolysis of the crude oil by the fireflood resulted in a lower sulfur content, a shift in the distillation curve toward increased amounts of lighter components and a slight increase in the API gravity and a decrease in viscosity.
The methane concentration in the produced gas increased during the fireflood. Evidence indicates that this methane increase was produced by coke gasification reactions rather than thermal degradation of the crude oil.
Oxidized Petroleum Fractions As Co-Surfactants And As Feedstocks For The Manufacture Of Sulfonates For The Tertiary Recovery Of Oil
Authors: Klaus E. E. , Jones J. H. , Nagarajan R. , Ertekin T. , Fan J. J. , Lin C. M. , Yarzumbek A. J. , King G. 
Published: December 2007

ABSTRACT
Pure paraffinic hydrocarbons and petroleum fractions (which may be aromatic-free) on vapor phase oxidation give an oxidized product useful as a co-surfactant and as a feedstock for the synthesis of sulfonates. The oxidations may be carried out in a simple tubular reactor using oxygen or air as the oxidant and nitrogen or steam as the reactor diluent and reaction-heat absorber. The reaction is non-catalytic and occurs readily at atmospheric pressure at temperatures ranging from 300 to 400°C.
The major products of the oxidations are cyclic ethers mixed with varying proportions of olefins and carbonyls. Mild conditions (low temperatures and the use of diluents) favor the formation of the cyclic ethers and other oxygenated compounds over olefins. The cyclic ethers are largely composed of 5- and 4- membered rings containing carbon and a single oxygen atom. Such products are useful as co-surfactants and as starting material for the manufacture of sulfonates.
The oxidized products which are rich in cyclic ethers react readily with sulfur trioxide or oleum to give sulfonates as the principal products. Such sulfonates are effective surfactants in tertiary oil recovery.
Low concentration slugs formulated from the above surfactants have performed well in core tests. Highest oil recoveries have been achieved by matching the ηmin of the slug with the EACN of the oil in place. Such matched properties always give slugs having low interfacial tensions with the oil to be recovered. The sulfonates in low concentration slugs without co-surfactants or viscosity control in the slug have produced oil in core tests at high efficiency levels.
Another Significant Step in the Evolution of Stimulation Treatments in the Muddy J Sand – Wattenburg Field
Authors: Harp Laddie J. 
Published: December 2007

ABSTRACT
Stimulation technology in the tight Muddy "J" Sand formation of the Wattenburg field has passed through another phase of development. This phase has centered in the changing of fluid type, fluid volume, proppant size and techniques of proppant scheduling with the result of much improved productivity in every case.
This paper presents a brief history of stimulation treatment development over the life of the field, the sequence of evaluation of treatment variables, and some of the thought behind the alterations that have been made.
The author was involved in seven of the treatment designs for the experimental wells included in the development of the improved treatment and procedure. The paper includes general treatment data and comparisons in productivity on three of the test cases which represent the pivotal steps in the ultimate evolution of the new treating approach.
All data, wells and results pertain to properties owned and operated by Amoco Production Company.
Formation Evaluation Utilizing Gamma Ray Spectral Analysis
Authors: Heflin Jearald D. , Nettleton Ken A. 
Published: December 2007

ABSTRACT
Since currently producing hydrocarbon reservoirs can no longer supply the world's energy needs, the search for new sources has led to another look at formations that have posed difficult evaluation problems.
Several formations encountered in the Rocky Mountain region are in this category. In the past, drilling or evaluation techniques could not accurately indicate productive and nonproductive zones. Three of the stratigraphic units which have proven difficult to evaluate with conventional surveys are the Niobrara, Mawry and Phosphoria.
Problems in evaluating these formations can result from several factors. Mast can be related to determining the true clay content for accurate lithology and resultant porosity determinations, the location of fractured or fracturable zones, and evaluating formations that contain a low or unknown salinity formation water.
Recent developments in wireline logging instruments provide measurements which enable these and other sequences with similar problems to be correctly evaluated.
These methods rely on the spectral analysis of natural and induced gamma rays. Two commercially available instruments that provide these measurements are the Spectralog and Continuous Carbon/Oxygen log.
This paper will present the theory of operation and parameters measured with these instruments. Applications of these measurements will be discussed, with field examples showing how these measurements provide an improved evaluation of these formations.
Texas Railroad Commission Drilling and Completion Filing
Authors: Richter Thomas H. 
Published: December 2007

Abstract
The drilling and completing of gas wells in the State of Texas has long been of interest to the Railroad Commission of Texas. The Oil and Gas Division is charged with the responsibility of regulation of the oil and gas industry for the purpose, of conserving petroleum and preventing its waste, providing for equity among owners, protection of usable quality waters from pollution above and below the ground surface, and safety of the public. All the forms which are required by the Commission for drilling, completing and producing a well are designed to satisfy the aforementioned responsibility. Through proper planning, a gas well can be drilled, completed and put on pipe line with an allowable with a minimum amount of paperwork or time lost (which is money). Erroneous form filing or delinquent form filing will only cost the operator of the well time and production, and can cause other operators in a competitive field the loss of usable allowable, and consequently, production.
This paper will cover all forms that are required to drill, complete and obtain an allowable in the State of Texas. Common problem areas on each form will be examined, along with several definitions. Commission notification requirements will be reviewed. Gas well testing procedures and required form submission in regard to timely filing will also be reviewed. Special problems associated with Cotton Valley completions will be discussed.
Unique Transformer Design for the Special Requirements of Electric Submersible Pumps
Authors: Owen Donald W. 
Published: December 2007

ABSTRACT
Electric submersible pumps require nonstandard voltage levels. A conflict between voltage versatility and power efficiency exists in many multiple voltage transformer designs. This conflict was resolved by a unique transformer design. A review of the fundamental considerations in power transformation and equipment protection is induced by the importance, cost and vulnerability of electric submersible pumping equipment.
The Analysis of Spherical Flow with Wellbore Storage
Authors: Brigharn William E. , Peden James M. , Ng Kitson F. , O’Neill Neil 
Published: December 2007

ABSTRACT
The theory describing the flow of fluid in a spherical system affected by wellbore storage has been derived. Type curves have subsequently been developed based upon this derived theory which facilitate the analysis of spherical flow behaviour dominated by wellbore storage at short times. The analysis of long time pressure transients when wellbore storage becomes less important is also discussed with reference to a cartesian plotting technique.
Finally the analysis of data from interference tests for isotropic and anisotropic systems is also discussed.