bluuebunny/crossref_metadata_2025_split huggingface dataset:
Buying Gas To Re-Sell Instead of Producing Gas To Sell
Authors: Williams H. D. , Lohrenz John 
Published: December 2007

Abstract
Since deregulation of natural gas prices in the U.S. became fact, not just intent, producers have had to reckon with the progeny of market supply and demand. Long-term speculations abound regarding improved gas prices in the future. Short-term speculative opportunities arise due to seasonal price peaks. One way of acting on these speculations is buying gas for re-sale instead of producing one's own gas; the decision algebra of such speculations is treated here.
Global Warming and the Emerging Importance of Natural Gas
Authors: Kamal W. A. 
Published: December 2007

ABSTRACT
The paper examines the environmental crisis facing the planet in the coming decades due to an enhanced ’greenhouse effect’, its causes and impacts. It then discusses future energy demands of industrial and developing countries and shows that the latter will face a huge energy crisis with serious consequences on the environment – unless a move to cleaner fuels is adopted. It finally examines the future prospects of Natural Gas, an abundant and relatively cheap · at today's prices – primary energy source which is the most environmentally-benign of all fossil fuels. The study demonstrates why Natural Gas is regarded as the fuel of the 21" century, and our hedge against a looming environmental crisis.
Production Data Analysis for Wells That Have Been Subject to Periodic Curtailment
Authors: Spivey J. P. , Lee W. J. 
Published: December 2007

Abstract
Gas wells are often subject to periodic or cyclic curtailment. Currently available methods are poorly suited for analyzing production data from these wells. Using methods presented in this paper, an equivalent continuous flowing pressure can be calculated from pressures measured at the end of the flow and shutin periods during each cycle. This equivalent continuous flowing pressure is then used for production data analysis in conjunction with the average flow rate. This method is applicable for boundary dominated flow, transient radial flow, and transient linear flow of slightly compressible liquids in a homogeneous formation. The method may be applied to gas well production data through the use of pseudopressure or normalized pressure.
Correlation for Determining Gas Condensate Composition
Authors: Niemstschik G. E. , Poettmann F. H. , Thompson R. S. 
Published: December 2007

Abstract
A correlation was developed that relates the composition of the well stream effluent at any depleted state to the composition of the retrograde gas condensate at its initial dew point pressure as a function of the fraction that the reservoir pressure is depleted, reservoir temperature and specific gravity of the retrograde gas condensate at its initial dew point pressure. The correlation is based on the analysis of 131 constant volume laboratory depletion studies on gas-condensate systems for a total of 907 depletion steps.
If the initial specific gravity of the gas condensate is not available, a second correlation was developed to predict the initial specific gravity.
Improved Acid Fracturing Treatment Designs Based on In-Situ Temperature Calculations
Authors: Roodhart L. P. , Kamphuis Harry , Davies D. R. 
Published: December 2007

Abstract
Successful acid-fracturing treatment requires the creation of etched channels of sufficient width and length. This paper shows how the channel shape can be calculated using knowledge of the acid/rock reaction process, in-situ temperature and hydraulic profile. A simulator has been developed for this purpose, on the basis of an implicit finite-difference scheme permitting rigorous treatment of all relevant processes, such as the cooling of the rock adjacent to the fracture and the heat transfer between fracture and wall during and after pumping, is employed. Detailed knowledge of the temperatures of both the fracture fluid and the rock face allows quantitative description of the progress of the acid/rock reaction. Model calculations show that the channels etched in calcitic rock may be very wide near the wellbore because of turbulence effects. On the other hand, the etched channels may be too narrow in dolomitic rock, or rock with a low fracture toughness. This will impair well productivity, and should be avoided by modifying the pumping scheme. Two field examples of treatment design and evaluation using the new simulator are discussed.
A Comparison of Short-Core and Long-Core Acid Flow Testing for Matrix Acidizing Design
Authors: Fambrough J. D. , Newhouse D. P. 
Published: December 2007

Abstract
Most acid core flow testing utilizes short (&lt;3") core plugs. In this study flow tests were run using both short core plugs and long(&gt;8") core plugs. All plugs were from a producing formation in the Gulf of Mexico. Both long and short cores were damaged with a fluid loss control pill and then treated with various acid systems. When treated with HC1 or HC1:HF the short core plugs showed an increase in permeability over the length of the core. Long cores treated with HC1:HF showed an increase in permeability in the first 2 inches of the plug but a decrease in permeability farther down the plug. Analysis of the spent HC1:HF indicated that the loss of permeability was caused by precipitation products from the HF/clay reaction. Observations made during these tests indicate that relying on short core flow tests for selection of a matrix treatment fluid can result in a damaging treatment. Long core tests provide a better tool for selection matrix treatment fluids.
Using an Expert System To Select the Optimal Fracturing Fluid and Treatment Volume
Authors: Holditch S. A. , Xiong Hongjie , Rueda Jose , Rahim Zillur 
Published: December 2007

Abstract
Many wells drilled and completed to produce oil and gas must be stimulated to increase flow rates and ultimate recovery. In low permeability reservoirs, long hydraulic fractures are required to optimize the depletion of the reservoir. In high permeability reservoirs, formation damage during drilling must be overcome using short, highly conductive hydraulic fractures.1 Most recently, in ultra-high permeability, poorly consolidated formations, a new stimulation method that combines both hydraulic fracturing and gravel packing principles (the FRACPAQ has been successfully used to stimulate oil and gas production.
To optimize production, one must optimize the fracture fluid properties, the treatment volume, and the fracture conductivity. Choosing the correct fluid and additives is extremely important to be sure the proppant is placed successfully. We also want to use a fluid that breaks and cleans up properly. Ideally, every fracture treatment should be designed by an expert with adequate data available. However, most fracture treatments are not designed by experts; instead, most stimulation treatments are designed by inexperienced engineers without all data they need.
We have developed a PC-based interactive computer model to help an engineer choose the best fluid, additives, and propping agent for a given set of reservoir properties.2,3 The computer model also optimizes the treatment volume based upon reservoir performance and economics. To select the fluids, additives, and propping agents, the expert system uses rules developed by surveying stimulation experts from different companies, reviewing the literature, then incorporating the knowledge into rules using an expert system shell. Our design expert queries the user for necessary reservoir data, then using the knowledge base, the expert system recommends the best materials for the treatment.
Reservoir Characterization of an Eastern Kentucky Devonian Shales Well Using a Naturally Fractured, Layered Description
Authors: Jochen J. E. , Lancaster D. E. , Holditch S. A. 
Published: December 2007

Abstract
This paper presents a summary of the complete integration of geological, geophysical, geochemical, and reservoir engineering analyses into a single reservoir model that accurately simulates observed production and pressure transient data fa-a gas well completed in the Devonian Shales of the Appalachian Basin in Pike Co., KY. This well was part of a three-well research program sponsored by the Gas Research Institute (GRI). Data collected and evaluated include a detailed openhole logging suite (including the formation microscanner), 240 ft of oriented whole core, open- and cased-hole stress tests, nitrogen slug tests, fracture treatment pressure data, and pre- and post-fracture pressure buildup tests. The purpose of this paper is to discuss the data collected on the well, to present the data analyses, and to demonstrate how the various analyses are being integrated to form a better understanding of the physical properties controlling well performance in the Devonian Shales. This paper also provides intrinsic reservoir properties, such as matrix permeability, desorption isotherms, and natural fracture spacings from the Devonian Shales that were measured in this well.
Cost Reduction of Injection Tests for Under-Pressured Reservoirs
Authors: Saulsberry J. L. 
Published: December 2007

Abstract
A new method for performing reduced cost injection/falloff tests in under-pressured reservoirs has been developed at the GRI sponsored Rock Creek research site. The new method referred to as the "Tank Test" uses gravity drainage from a water storage tank to inject water into the reservoir. The primary advantages of Tank Test over the traditional injection/falloff tests are reduced costs and improved test results. The tank test eliminates the need for expensive pumping equipment and the manpower required for manual pump rate adjustments. Further cost savings can also be made by using gauges intended for ground water monitoring in place of oil field gauges when downhole shutin is not required. The low cost of the Tank Test allows longer duration tests to be economically performed so that the radius of investigation of a test is extended. The Tank Test also reduces the possibility of fracturing the reservoir during the injection portion of the test which is a common problem when testing shallow low permeability reservoirs. This paper describes the circumstances under which the Tank Test is most applicable, the equipment that is required and how to perform the test. The paper presents results of field tests performed on coal seams and a test performed on an Antrim Shale well. A simple Tank Test design procedure is also provided.
Economic Evaluation of Nitrogen Injection for Coalseam Gas Recovery
Authors: Stevenson M. D. , Pinczewski W. V. , Downey R. A. 
Published: December 2007

Abstract
This paper presents a scoping study to investigate the economic viability of nitrogen injection to improve the recovery of coalbed gas. The sensitivity of the analysis to key reservoir parameters is also presented.
The results of the study suggest that nitrogen injection may be more attractive than conventional pressure depletion for lower permeability formations where the loss in permeability with pressure decline is significant. Nitrogen injection economics are shown to be very sensitive to the costs associated with injection and separation and are adversely affected by reservoir heterogeneity.
Liquid Fuels and Petrochemicals From Natural Gas: A Canadian Perspective
Authors: Fouda S. A. , Galuszka Jan , Sekhar M. 
Published: December 2007

Abstract
Canada is blessed with vast reserves of natural gas. A large portion of the reserves is in the frontiers and remains unexploited due to the prohibitive cost of transporting the low energy density gas. Moreover, only a small portion of Canada's consumption of natural gas is used as a chemical feedstock. Current conversion technologies involve an initial steam reforming step to produce synthesis gas which is then converted to methanol, gasoline or other products. These indirect routes are energy intensive and costly. Enormous market opportunities can be created especially for remote natural gas by developing new direct conversion technologies.
The development of direct conversion routes is at an early stage. Oxidative coupling of methane to ethylene and partial oxidation to methanol are the two routes most investigated. Engineering and economic evaluations indicate, for both routes, that the product selectivities are less than desirable due to the deep oxidation of the reaction intermediates or products to form carbon oxides.
Aggressive R&D is needed in catalyst design, reactor design and process design to overcome these chemical and engineering challenges and speed the development of direct conversion routes to commercial viability.
Case Study: HPHT Casing Design Achieved with Multistring Analysis
Authors: Goodman M. A. , Halal A. S. 
Published: December 2007

ABSTRACT
Conventional casing design is based on single-string analysis which ignores annulus fluid heat-up loads and composite cemented string effects. This paper presents the design of a 7" production casing and 10-3/4" × 9-5/8" protective casing under high burst/collapse conditions. Uniaxial and triaxial safety factors are computed and compared for single-string versus multi-string analysis with and without temperature loads. In the multi-string analysis, casing stresses are calculated for the radially composite structure assuming the elastic properties of casing, cement, and formation. Results demonstrate a significant increase in burst safety factor for cemented casing and show that burst/collapse tendency for HPHT wells is strongly dependent on multi-string top-of-cement locations. For this HPHT application, reliable triaxial design is achieved with multi-string analysis using standard weights and grades of casing, which otherwise is not possible with single-string uniaxial analysis.
Integrated Approach to Bit Programming Improves Drilling Efficiency of Offshore Mobile Wells
Authors: Spaar J. R. , Brown L. A. , Goodman H. E. , Bomar B. B. 
Published: December 2007

ABSTRACT
Historically, the development of a bit program for a proposed well merely involved the optimization of bit designs that have proven successful in the targeted area. While this approach appears to optimize bit performance, it does not take advantage of rock strength information that is now available.
This paper describes a new approach to bit programming and its impact on a challenging multi-well program in Mobile federal waters. The bit program, which employed rolling cone and fixed cutter bits, incorporated a new revolutionary Rock Mechanics Algorithm (RMA) that is based on lithology and sonic log intrepretation. Central to the success of the program was a thorough understanding of both fixed cutter and rolling cone bits in different drilling conditions. The evolution of bit programming for the Norphlet in the Mobile area offshore Mississippi will be detailed.
Utilization of the aforementioned analytical tools in formulating a bit program for a Mobile program resulted in a 22,489-ft. exploratory well being drilled 32 days ahead of schedule. This resulted in a substantial reduction in the cost per foot drilled as compared to the previous wells drilled in this five-well campaign.
Unique Rock Bit Cutter Fabrication Technology Provides Bit Design, Performance, and Reliability Breakthroughs
Authors: Nixon M. S. , Walter J. C. 
Published: December 2007

ABSTRACT
The development of a patented powder metal forging technology for making rockbit cutters is the first major innovation in rockbit manufacturing technology since the development of the insert bit. Rapid, solid state densification of a net shape cutter eliminates many conventional cutter design constraints and provides advanced materials options that significantly improve cutting structure integrity.
A review of the new manufacturing process and comparison with conventional methods will highlight the design and materials capability and reliability improvements intrinsic to this solid state densification process.
Prototype bits made using this technology duplicated the cutting structure and materials used in standard IADC Type 11 roller cone bits. These bits demonstrated the process capability and potential, and provided insights into design and process improvements used in second generation bits. Field test results from the second generation bits that employed more advanced profile designs and cutting element materials demonstrated the potential impact of this new class of rockbit on drilling cost.
Powder metal cutter (PMC) bits from the prototype program and phase one of the project have been successfully run in typical Type 11 bit applications. The materials and design options available indicate the capability to address a wide range of soft and medium soft drilling applications economically by linking PMC with state of the art bearing and hydraulic design technologies.
Offshore Drilling in the North Sea
Authors: Belknap William B. 
Published: December 2007

Introduction
Much has been learned during the first 3 years of drilling in the U.K. sector of the North Sea. Generally, conditions have been difficult. Although few conditions can be pointed out as being the worst known, many of pointed out as being the worst known, many of the conditions are among the worst and require considerable attention to engineering and plannings. plannings. This paper discusses various aspects of planning and drilling exploratory and planning and drilling exploratory and development wells in the North Sea. It covers the initial planning of equipment to drill exploratory wells; some of the problems encountered in drilling these wells; Phillips' solution to these problems, and finally the planning of a directional drilling program for shallow gas production from a fixed platform of limited production from a fixed platform of limited area.
Prior to selecting drilling equipment for a project like this, consideration must be given to the weather conditions, water depths, drilling depths, rig mobility, availability and logistics of moving materials and supplies, means of transportation and numerous lesser considerations.
This paper presents one major operator's solution to the many problems and considerations. There are other ways of doing many of these things and reaching the same end point. There are other problems which we did not encounter. We believe that, in general, we have used a practical and economical approach to drilling in the North Sea.

EXPLORATORY DRILLING EQUIPMENT
Since most of the Phillips group's concessions were in water of less than 200-ft depth, a self-elevating platform-type rig was selected rather than a floater or semisubmersible. The self-elevating rig was preferred to a fixed platform-type for exploratory operations because platform-type for exploratory operations because of mobility and to a semisubmersible because of fixed position and increased efficiency by eliminating wave motion. Because of severe weather in the North Sea and availability of rigs for deep water operation, it was decided to contract The Offshore Co. to build a new rig for this operation. Consequently arrangements were made to construct the North Star drilling rig at John Brown shipyard in Clydebank, Scotland.
As originally equipped, the North Star rig is capable of drilling in 150-ft water depths in the North Sea. Additional leg sections can be installed to increase the water depth capability to 200 ft. We did not find this necessary in our exploration program. The general appearance of the platform can be seen in Fig, 1. The dimensions and capacities of the barge hull equipment are as follows.
Integrated Design by Design: Educating for Multidisciplinary Teamwork
Authors: Thompson R. S. 
Published: December 2007

Abstract
This paper addresses the multi-disciplinary educational needs of the petroleum engineer. Petroleum engineers, as multi-disciplinary team leaders, will continue to play key roles in the future of the petroleum industry. Working and functioning in a multi-discipline team of geologists, geophysicists, and petroleum engineers is especially difficult since each team member brings a different perspective to the team. It is this same difference in perspective that makes multi-disciplinary teams an economic and effective approach to problem solving. The key to educating for multi-disciplinary teams is to recognize important behavioral issues and to incorporate these into the curriculum. This paper addresses these issues and demonstrates how they can be incorporated into the petroleum engineering curriculum.
Drill Cuttings Reinjection for Heidrun: A Study
Authors: Crawford H. R. , Lescarboura J. A. 
Published: December 2007

Abstract
Drilling of 56 wells from the Heidrun Platform in the Norwegian North Sea may generate about 150 million pounds of drill cuttings. If oil-based mud (OBM) is used on any of the wells these oily cuttings will need to be disposed of in an environmentally sound manner. This study was to assess the feasibility of disposing of these oily cuttings by reinjection into a fracture, initiated from a purpose-drilled reinjection well. A slurry was prepared from OBM drill cuttings from the Norwegian North Sea using a commercial cuttings slurrying system. Laboratory and pilot-plant tests of this slurry were conducted to measure: composition, rheology, laminar and turbulent friction loss, and leak-off coefficient. Laboratory tests were performed simulating the flow of the slurry along a fracture in a permeable formation with leak-off occurring from one side of the fracture. The paper describes the results of the tests. It concludes that it is feasible to dispose of the cuttings by reinjection into a fracture created in an impermeable formation. A procedure is suggested. It theorizes that permeable formations can act as barriers to the vertical growth of the fracture.