bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the Performance of Noncontinuous Tight Gas Sands
Authors: Ubani E. A. , Ray R. M. 
Published: December 2007

ABSTRACT
This paper discusses the development and application of a stochastic three-dimensional reservoir model for gas-water flow. The model treats the occurence of natural fractures and shales in the reservoir as random, and as such the discontinuities may be arbitrarily distributed among the reservoir grid blocks. A simple shale management scheme that does not require the formulation of a sand-shale permeability relationship 1s used. However, the developed model requires the estimation of effective flow properties for the fractured reservoir nodes. By this, we attempt to simulate the effective permeability measured by the slope of a fractured reservoir build-up curve. The model may be used to compute the reservoir performance of a fractured, lenticular sand gas reservoir as well as that of a conventional blanket sand. Results of demonstration problems based on published data on Paludal zones 3 and 4 of the Mesaverde formation 1n western Colorado suggest that the effects of sand lenticularlty may not be as marked as have previously been calculated by modifying sand thickness by sand lense factor.
Measurement of Longitudinal Dispersion Coefficients for Gas Flowing through Porous Media
Authors: Newberg M. A. , Foh S. E. 
Published: December 2007

ABSTRACT
The Institute of Gas Technology's Sustaining Membershp Program is currently sponsoring research to investigate the use of inert base gas for natural gas storage fields. As part of that program, an apparatus was constructed in which to measure longitudinal dispersion of gases flowing through porous media. Whole core samples from several underground storage reservoirs were confined in a Hassler type coreholder. Two different gases (methane and nitrogen) were successively flowed through the core and the effluent concentration profile was recorded. Superficial pore velocities varied from 0.25 to 3.5 ft/hr [0.02 − 0.3 mm/s], and pore pressures were in the range of 500 − 1000 psi [3450 − 6890 kPa]. A single parameter diffusion-type equation was used to correlate experimental results. This model is used to generate longitudinal dispersion coefficients and "scale of dispersion" (dispersion coefficient divided by velocity).
The rate and degree of mixing of two gases in porous media seems to be predominantly controlled by three factors: the porous media itself, the viscosity ratio of the two gases, and the superficial pore velocity of the gases. Specifically: Mixing parameters were found to vary widely with different porous media, but do not see to be directly related to permeability, porosity, or tortuosity.In most cases, the values of dispersion coefficient and mixing length for an unfavorable viscosity ratio were greater than those for the favorable case. The magnitude of the difference between the two cases varies with different porous media.Dispersion coefficient increases with increasing velocity. This dependence may be linear for favorable viscosity ratios and some porous media. However, it is often not linear and needs to be measured for each porous media and set of gases.
Gas Research Institute Underground Gas Storage Research Program: An Overview
Authors: Shikari Yusuf A. 
Published: December 2007

ABSTRACT
The Gas Research Institute (GRI) is currently involved in the development of concepts aimed at an enhancement of natural gas service to the consumer. In order to maintain the attractiveness of the gas options to industrial consumers, and to reinforce the "value-in-use" of natural gas to residential as well as commercial customers, it is essential to develop efficient, economical, and safe means of reducing the "cost-of-service", including that of natural gas storage in underground formations. Specifically, research and development (R&D) is needed to explore ways to better utilize existing storage fields and also to develop new storage facilities at minimum cost.
GRI is currently examining the feasibility of using foam in underground gas storage fields as a mobility control agent to reduce gas migration. Research is also being conducted to establish economic viability of substituting less-costly inert gas(es) for a portion of the base gas, to understand the gas-gas phase mixing behavior in gas storage fields via laboratory experiments and reservoir modeling, and to develop cost-effective gas separation processes using membranes.
This paper provides an overview of the GRI's Gas Storage R&D Program and highlights key results achieved to-date for selected research projects.
Subsurface Pressures and the Fracturing Gradient in Hydraulic Fracturing of Subsurface Formations
Authors: Luchetta John 
Published: December 2007

American Institute of Mining, Metallurgical and Petroleum Engineers, Inc.
This paper was prepared for the SPE Rocky Mountain Regional Meeting to be held in Casper, Wyo., May 22–23, 1967. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copies. The abstract should contain conspicuous acknowledgement of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made.
Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

Abstract
Hydraulic fracturing calculations often employ fracturing treating gradients based on the total treating pressure applied at the sand face. Data presented in this paper indicate that more accurate predictions of fracturing pressures and fracture orientation result when reservoir pressure is considered. By this means, the fracturing gradient is reduced to a property of the rock only and more consistent values over wider ranges are prevalent.
Also, it is observed that values for vertical fracturing gradients very closely approximate values for subsurface horizontal stress as predicted by Hook's law.

Introduction
Analysis of pressures in large bodies of water follows straightforward laws of hydraulics whereby the pressure exerted at any particular depth is equal in all directions. In contrast, the pressures at depth in a sedimentary basin may be different in all directions. This difference in pressure greatly influences the choice of engineering techniques and design of hydraulic fracturing operations [see Figs. 5 through 7].
The force resisting formation parting has been represented by the sum of the instantaneous shut-in pressure and the hydrostatic head of fluid above the formation.
Application of this relation to field problems has been less than satisfactory in many instances because recent data are not available and it is often difficult to predict fracturing characteristics.
The purpose of this study is to propose an innovation to this concept that will give more accurate results and better describe the mechanism of the fracture gradient.

Discussion
As demonstrated by Hubbert and Willis, propagation of fractures in rock formations under hydraulic influence conforms to definite laws of mechanics and strength of materials as follows.
If the fluid pressure is applied locally within rocks and increased until fracturing of the rocks occurs, the plane along which fracturing will first occur is perpendicular to the least principle stress.
The Use of Inert Base Gas in Underground Natural Gas Storage
Authors: Misra B. R. , Foh S. E. , Shikari Y. A. , Berry R. M. , Labaune F. 
Published: December 2007

ABSTRACT
The use of less expensive inert gas to substitute all or part of the base gas requirements in underground natural gas storage fields is a promising technology that has been successfully field tested in France. This paper discusses geological, reservoir, and operational factors that need to be considered in selecting an underground storage field for inert gas use. A storage field in the U.S. has been selected to illustrate detailed data collection and analysis that will lead to formulation of a plan to inject inert gas and predict long term field performance using reservoir models.
High base gas fraction, the presence of closed structure or an isolated area away from the injection/withdrawal wells, absence of large scale heterogeneity, and availability of adequate data for reservoir modeling are favorable features that would make a field an attractive candidate for inert gas use. The degree to which natural and inert gases will mix during the storage field operations can be predicted with the help of reservoir simulators now available.
Natural Gas: An Emerging Fuel in Indian Energy Scene
Authors: Mittal A. K. , Gupta A. K. , Goyal K. L. 
Published: December 2007

ABSTRACT
The natural gas industry is a relatively new entrant in the Indian energy sector, it is on the verge of making significant contribution to the Indian economy and is expected to significantly contribute to reduce Gross Domestic Product - energy elasticity coefficient.
The seven fold increase in natural gas reserves during last twelve years have generated an optimism for future gas discoveries in Indian sedimentary basins. The natural gas production is expected to increase nearly five folds by the turn of century from the present level of eight billion cubic meter per annum. In this paper, an attempt has been made to determine an appropriate pattern for optimal utilisation of these large potentials of natural gas resources.
Presently, the priority use of gas is considered as feedstock in fertiliser sector. The relative scarcity of commercial fuels coupled with the burgeoning energy demand have paved the way for natural gas utilisation in other sectors. Systematic analysis has been carried out to determine the competitiveness of natural gas vis-a-vis other fuels/feedstocks in different sectors, taking into account, their historical growth trend.
The analysis indicate about eight fold increase in the deficit of power by the turn of the century, which can be economically and efficiently narrowed by the gas based power plants. The major portion of petroleum demand in transport and domestic sectors, presently met by import of middle distillates, may be substantially supplemented by natural gas, in future. Case studies for fuel replacement by gas, in these sectors, have also been discussed.
The integrated national development is expostulated by the development, distribution and diversification of natural gas through a ‘National Gas Grid’.
Gas Energy Supply Outlook: 1987–2010
Authors: Kalisch R. B. 
Published: December 2007

ABSTRACT
Natural gas supplies are expected to be adequate to meet current consumption levels under all likely gas price scenarios throughout the period 1987-2010. At a maximum, potential supply capability could increase to 30% over peak U.S. consumption levels experienced in the early 1970s.
These gas supply estimates include the domestic lower-48 sources which consist of conventional gas production, gas from tight formations, coal seam gas and gas from co- production of gas and brine. These potential supply capability estimates have been developed without regard to specific gas demand constraints.
Acid Gas Treating at the Arun NGL Plant and Its Modifications
Authors: Purwonohadi P. , Soeryanto J. 
Published: December 2007

ABSTRACT
At PT Arun, there are six LNG trains, each with its own treating system. The acid gas treating unit is the front end process of each LNG train, which reduces the CO2 content of the feed gas from 14.85 volume % to less than 0.05 volume % and the H2S from 80 ppm to less than 5.0 ppm by volume. Each treating unit was originally designed to process 314,359 Nm3/h of sour feed gas by using a proprietary Benfield Hi-Pure process.
In late 1979, a study was conducted by Bechtel Inc. to improve the treater capacity and reliability. At that time, modifications were made to the packing, exchangers, and piping, the capacity was improved from it's original design.
In 1983-84, a debottlenecking study was conducted to improve the train LNG capacity and concluded that both the carbonate and amine absorbers were a bottleneck. It was determined that the limitation in the unit was due to poor liquid distribution in the tower packing. The absorber liquid distributors were changed from a "V-Notch" to an "Orifice Riser" type, improving the treating capacity approximately 22% to 28%.
Presently, a new improved liquid distribution system has been installed in one of the the train's carbonate regenerator. This improved the regenerator efficiency from 170 to 190 SCF CO2/LB mole steam. We are now proposing to install this new type of distributor in the remaining five trains in the next scheduled shutdowns (1988-89). A continuing effort to improve the plant treating capacity is still on going at the Arun NGL plant.
Hydraulic Fracturing of a Horizontal Well in a Naturally Fractured Reservoir: Gas Study for Multiple Fracture Design
Authors: Yost A. B. , Overbey W. K. , Wilkins D. A. , Locke C. D. 
Published: December 2007

ABSTRACTStimulation of a naturally-fractured, low permeability, low-pressure 2000-foot horizontal well in a low permeability reservoir and in-situ stress environment requires careful stimulation fluid design to minimize the capillary retention of treatment fluids. Therefore, a systematic approach to stimulation design using N2, CO2, and N2-foam was used to select one which is most efficient. Stimulation modeling was used to evaluate fracture geometry with particular concern for the minimum pressure rise above parting pressure required for height growth during frac fluid injection. Up to seven zones along the horizontal wellbore are available for stimulation. Each zone was ranked and pre-frac tested to establish pre-frac permeabilities. A N2 and N2-foam data frac was performed in one zone to establish leakoff characteristics. Subsequently, N2, CO2, and N2-foam treatments were performed on a 400-foot zone to evaluate the effectiveness of CO2 versus N2 frac fluids. Both the data frac and subsequent stimulations were evaluated in the two least productive intervals in order to use the preferred fluids in the best zones in the reservoir. The post-treatment decline curves for N2 and CO2 indicate a CO2-based fluid treatment should be performed in the most productive interval to achieve maximum success. Results of the stimulation conducted are presented along with discussion of improvement ratios and potential utility to other horizontal drilling projects.
Operating Problems in the Hanlan Swan Hills Gas Field
Authors: King W. J. 
Published: December 2007

ABSTRACT
The design, construction, startup, and operating phases of major projects involve several different people. Operating problems encountered subsequent to initial startup are not always communicated to designers. This can result in design errors being repeated and costly modifications being required after initial construction.
The intent of this paper is to review several operating problems encountered in producing the Hanlan Swan Hills gas field since startup in March 1983. These problems and the resulting recommendations should be considered in the design and operation of future deep sour gas systems.
Assessment of Gas Production Potential From Coalbeds and Adjacent Strata.
Authors: Layne A. W. , Siriwardane H. J. , Byrer C. W. 
Published: December 2007

ABSTRACT
Pipeline quality gas production from the highly fractured methane-bearing strata above longwall coal mine panels is predicted to be many times that of the gas-in-place estimate for the minable coalbed. This production is thought to come from relatively shallow gas-bearing coals, organic shales, and sandstones. In the mining process, permeability of shallower strata is increased significantly because of the fractured zone generated during longwall mining activity and, hence, gas could be produced at volumes many times that of an average conventional gas well. This paper assesses the potential production and the influence of well spacing on the drainage of gas from the strata above mining operations in southern Appalachia. In this assessment, gas reserves were quantified for a typical failure zone, formation gas content, and geologic cross section present in the Appalachian Basin. A finite element method was used to determine the size and shape of the affected stratigraphic areas for which gas contents were estimated (based on prior knowledge). A two-phase reservoir model was used to compute increased production rates from methane wells that penetrate the multiple strata and coalbed. Production data from actual wells above a longwall panel were history matched to characterize flow mechanisms and reservoir properties. These properties were then evaluated in parametric studies to determine the influence of well location on gas production. Results indicate that cumulative gas production can be increased by placing wells farther apart than 1,000 ft (304.8 m). The model appears to make reasonable predictions of the size of the multi-reservoir area in complex geologic conditions. The study considered the influence of an advancing mine face on gas production. Thus, the methodology presented in this paper is applicable to the location of gas wells in highly fractured reservoirs to optimize long-term gas production.
On the Quality of Data From Standard Gas-Condensate PVT Experiments
Authors: Drohm J. K. , Trengove R. D. , Goldthorpe W. H. 
Published: December 2007

ABSTRACT
From an analysis of the constant volume depletion experiments performed on 80 gas-condensates, it is concluded that serious problems exist in the detection of the actual volume of retrograde liquid in the PVT cell. The measured liquid volume is usually only a fraction of that required to give realistic liquid densities. The frequently observed concave shape of the retrograde liquid saturation curve close to the dew point is not real and is the result of experimental error. It is recommended that the data quality be improved by directly measuring the retrograde liquid density because it provides an excellent control over the liquid saturation, especially when this saturation is low.
The properties of the fluid initially in the PVT cell are normally determined mathematically. However, this often only approximates the true properties and deviations can have consequenses for the derived liquid properties. The direct measurement of the composition and properties can easily solve this problem and is therefore strongly recommended.
The analysis of the experiments leads to the following statements for constant volume depletion experiments liquid densities are monotonically decreasing with pressureBom and Rsm are both monotonically increasing with pressure.
Here Bom is defined as the inverted partial density of the C5+ component fraction in the liquid, while Rsm is the mass ratio of the effraction over the C5+ mass fraction.
Microwave Technique for Phase Behavior Studies of Petroleum and Natural Gas Mixtures
Authors: Rogers W. J. , Eubank P. T. , Hall K. R. , Holste J. C. 
Published: December 2007

ABSTRACT
We have developed a new technique that utilizes microwave energy to study the phase behavior of mixtures at the extreme temperatures and pressures encountered in petroleum and natural gas reservoirs. Our technique measures shifts in a static microwave energy field caused by changes in sample properties on a phase boundary. The appearance of a second phase produces detectable changes in the microwave resonant frequency and power. The new method does not involve inaccurate or unsafe procedures such as visual observation of samples, interpolation of isochoric slopes, or compositional analysis of samples drawn from the sample cell. Only small sample cell volumes (&lt;10 cm3) are required.
The microwave technique is effective with all types of fluids, light and heavy, nonpolar and polar, inert and corrosive, and it performs well at extreme conditions of pressure and temperature. A magnetic mixing pump enables preparation of homogeneous mixtures of fluids within the apparatus at experimental conditions. Measurements can be made at constant volume or at constant temperature. At constant volume, the microwave technique can determine phase boundary temperatures to better than 0.1 K. Pressure accuracy depends on the method of measurement. Results for phase boundary determinations of acid-gas mixtures with small amounts of heavy oils at high pressures and temperatures are presented.
Performance Data Through 1987 of the Isenhour Unit, Sublette County, Wyoming, Polymer-Augmented Alkaline Flood
Authors: Doll T. E. 
Published: December 2007

ABSTRACT
The Almy sands in Sublette County, Wyoming have some 19 years of volumetric sweep improvement history. In an effort to reduce residual oil saturation in the swept area, the first field-wide alkaline flood was initiated in September, 1980 at the Isenhour Unit.
Based on core testing, crude oil-alkaline agent screening determined that soda ash (Na2C03) and anionic polymer would be most beneficial in reducing interfacial tension (IFT) and mobilizing residual oil. Core flooding indicated that alkaline agent could be injected into the high clay content Almy sand. A significant decrease in oil saturation on a percent pore volume basis was predicted.
This paper details flood performance up to January 1, 1988. Injection is now 67.2% of the total pore volume. A cationic and anionic polyacrylamide spearhead preceded the addition of the alkaline agent. Anionic polyacrylamide followed for mobility control. The program utilized a tripolyphosphate-anionic polymer blend for long-term wettability control and alkaline slug stability. Fresh water injection continues this date. Recovery to-date is 26.4% of the 00IP. Oil production inclined at a rate of 20% per year since the start of the polymer augmented alkaline flood to 1985. Oil production then declined at approximately 35% per year until mid-1987 with the drilling of #15 for the southwestern expansion of the reservoir.
Improved Gas Migration Control in A New Oil Well Cement
Authors: Fery J. J. , Romieu J. 
Published: December 2007

Abstract
Problems created by the migration of gas in drilling and production cements are well-known today. Intensive testing on new laboratory equipment led to a recently developed system resulting in a cement which has excellent mechanical properties and is efficient against gas migration.
Two new products were combined to achieve this result: –a polymer able to produce a gummy substance when the cement sets, which forms a tight barrier in the cement,–a new type of binding material made of Portland class G HSR cement blended with blast furnace slag wich has high mechanical properties and very low porosity.
Their field applications in well cementations are as different as high temperature or shallow gas problems.
In this paper laboratory research on gas migration and on these new products as well as results of their application in the field are reviewed.