bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Compact High-Performance Absorber for Small-Size Remote Field Gas Processing
Authors: Chakma A. , Islam R. 
Published: December 2007

Abstract
A compact high performance mass transfer device capable of producing very high interfacial area and turbulence is described. Interfacial areas as high as 106 m2/m3 of absorber can be obtained which is considerably higher than coventional mass transfer devices. This allows the absorber to be compact and therefore makes it suitable for use in small scale gas fields and in remote field operations where conventional gas processing technology is not economical. This paper provides the theoretical basis of mass transfer enhancement, experimental mass transfer and fluidodynamic data for this absorber. Design equations are provided and other potential applications are discussed.
Four Pressure Buildup Analysis Techniques Applied to Horizontal and Vertical Wells with Field Examples
Authors: Salamy S. P. , Locke C. D. , Overbey W. K. , Yost A. B. 
Published: December 2007

Abstract
Pressure build-up analysis of Devonian shale gas reservoirs is very critical and essential for determining the reservoir formation properties such as the flow capacity (Kh), skin factor (S), and the average reservoir pressure (P̄). Due to the complexity of the shale reservoir (its typically very low permeability and the presence of a dual porosity system), valid and accurate results of pressure build-up analysis are important to the optimization of individual well completions or depletion plans for gas reservoirs in the shale. Horizontal wells may allow operators to take better advantage of the shale fracture systems and anisotropic flow regime, but they present a new challenge for well testing and analysis.
This paper documents a technical procedure with field examples, using pressure build-up data from horizontal and vertical wells, to assist the reservoir engineer in evaluating the reservoir prior to any decision-making process. This procedure implements two conventional build-up analysis techniques: (1) type curve matching, and (b) Horner's technique. Pressure and pressure-derivative values are used to estimate values of skin, flow capacity, and average reservoir pressure. A newly-developed technique known as the rectangular hyperbolic method (RHM) is implemented in the pressure build-up analysis for comparison to results determined by the previous techniques. The RHM technique is accurate/valid for estimating the various reservoir properties and, in particular, the average reservoir pressure. In addition, reservoir engineering simulation is used to verify the results of the various techniques by using either the pressure build-up data or the production history for the history matching process.
Tender Assisted Drilling – NPD Experience
Authors: Mathiesen R. 
Published: December 2007

Abstract
TAD systems are in use and planned for future usage in the Norwegian Continental Sector of the North Sea. The NPD experience has been positive when compared to more traditional field development designs. The paper will explain the advantages gained by such TAD systems with respect to risk to personnel, environment and invested equipment.
The main contributing factors fall under the category of frequency of ‘Residual Accidental Events’, which appear to be lower with TAD systems.
The bridging system providing a safe protected escape route from such accidents as blowouts, riser ruptures, fires and explosions on either the wellhead platform or the TAD vessel, is the single most beneficial sub system.
Both the wellhead platform and the TAD vessel, is the single most beneficial sub system.
Both the wellhead platform and the TAD vessel are built or upgraded to meet NPD regulations for production installations.
The Tommeliten Subsea Project
Authors: Solheim A , Prichard M , Newcombe R 
Published: December 2007

ABSTRACT
The paper will present the Tommeliten Subsea Development Project with emphasis on the X-mas tree and control systems. The experience from the test phase is also highlighted.
The Subsea development of the Tommeliten field was interesting and special with regard to utilizing an existing platform system with a different operator/-owner for processing and distribution. It is also one of the first fields being developed with a 10,000 psi X-mas tree system.
The trend of activities in the North Sea is towards smaller and less expensive development solutions.
The field is marginal and was developed with an economically sound solution.
Hydrate Mitigation in a Deepwater Production System
Authors: Setliff S R , Parfitt G M , Chilton T S 
Published: December 2007

Abstract
Deepwater developments such as the one depicted in Fig 1 rely on production flowlines to carry raw, unprocessed reservoir fluid, called full wellstream (FWS) production, from wells to production facilities. As the search for reserves has taken the petroleum industry into deeper water and colder environments, the feasibility of producing FWS may become questionable due to the possibility of hydrates in the flowlines. The lower capital investment of FWS production flowlines is also attractive in shallower water. Even here, the risk of hydrates raises questions of feasibility in shallow, cold water environments.
When hydrates form in production streams, they can pose problems with economic consequences. Field experience indicates that hydrates occasionally obstruct production flowpaths (Ref 1 and 2). In the event of a partial obstruction, hydrate formation is a nuisance, slowing the production stream until the obstruction can be removed. And, in the event of a complete obstruction, full stoppage of production can last for weeks while mobilizing equipment to remove the obstruction. The cost of the mobilization on top of the lost revenue from the interruption in production can have serious economic repercussions.
Figure 2 is a hydrate formation curve for a crude oil reservoir fluid with a gas-oil-ration (GOR) of 1000 SCF/STB (177 SCM/STCM). Note that increasing pressure or decreasing temperature favours hydrate formation. The worst exposure to hydrate formation usually is associated with a prolonged interruption in production, when the pressure rises to shut-in wellhead pressure (SIWHP) and the contents of the flowline cool to seabed temperature. While hydrate formation will be more likely in deep water, even at typical seabed temperatures in the North Sea (40-45°F or 4-7°C), hydrate formation is possible.
Air Diving Inspection of Offshore Facilities: The Advancement of Transferring Under Pressure Within The Air Range
Authors: Neal B. R , Townsend A. R 
Published: December 2007

Summary
This paper addresses the following related subjects: iThe different types of diver deployment and retrieval systems in present use within the UK Sector.iiTotal Oil Marine's successful experience of using a HYBRID BELL system in conjunction with the technique of TRANSFER UNDER PRESSURE for platform based air diving operations during 1988.
Image Analysis of Reservoir Pore Systems: State of the Art in Solving Problems Related to Reservoir Quality
Authors: Davies D. K. 
Published: December 2007

Abstract
Image analysis is rapidly emerging as a promising new technology for the quantification of pore geometry. This paper presents reservoir-oriented applications of pore geometry analysis with particular emphasis on reservoir quality (porosity and permeability).
Image analysis consists of a computer-based, systematic procedure which quantifies those aspects of porosity that are visible using a 2 dimensional image (thin section or SEM image). This allows for identification and quantification of the size, shape, distribution and volume proportions of different pore types (pore geometry). In terms of producibility, pore geometry can be more important than total porosity particularly in rocks with less than 25% porosity.
Two examples are presented that demonstrate the application of image analysis of reservoir pore systems to problems related to formation damage and reservoir quality. In the first example, pore geometry derived from sidewall cores is related to test results in an offshore well. There is a direct relationship between pore geometry and flow rates. Zones that under-produce their pore system are identified as potentially damaged zones.
In the second example, pore geometry is related to test results, routine core analysis and log response (specifically deep induction and sonic travel time). A rock-based log model is developed to identify Rock Type units on a foot-by-foot basis in cored and non-cored intervals.
Stability of Clay Minerals in Acid
Authors: Simon D. E. , Anderson M. S. 
Published: December 2007

Abstract
Hydrochloric (HCl) acid is commonly used to acidize sandstone formations. Although much emphasis has been placed upon the dissolution and reprecipitation theories for acidization with hydrofluoric (HF) acid, little information is available concerning the effect of HCl acid on clay minerals commonly found in sandstone formations. While clays are not truly soluble in HCl acid, exposure to HCl acid does affect the structure of clay minerals.
This paper presents results of acid stability studies conducted with chlorite, illite, and kaolinite Clays. Initial testing utilized solubility analyses to determine which minerals are affected by acid. A second series of tests utilized x-ray diffraction analysis to determine the effect of HCl acid on the crystalline structure of the clays. Chlorite was found to be the most susceptible to acid attack. The reaction of acid on chlorite was found to be dependent upon HCl strength and temperature. A third series of tests evaluated the effects of weak HCl, formic, and acetic acid.
Diffraction studies, coupled with fluid analyses, revealed that the mechanism of acid attack is the leaching of ions from the matrix of chlorite clay. By-products of the acid dissolution of chlorite clay are of concern because they can cause formation damage. When the crystalline structure is destroyed, a significant amount of amorphous residue remains. The leached ions (primarily iron and aluminum) can precipitate as the acid is neutralized.
In addition to the diffraction studies, permeability change flow tests were conducted utilizing formation cores with high chlorite content. The results of these tests demonstrate that formations containing chlorite clay can be acidized successfully, provided that clay content, acid strength, and bottomhole temperature are considered in the treatment design. The flow tests also demonstrate that where extremely high chlorite contents cause acid sensitivity, organic acids may serve as acceptable breakdown and stimulation fluid systems.
Gravel Packing Horizontal and Highly Deviated Openhole Completions Using a Single-Screen Prepacked Liner in Offshore California Fields
Authors: Ashton J. P. , Liput J. , Lemons R. , Summerlin J. 
Published: December 2007

Abstract
A major operator has successfully gravel packed two long interval wells in the Giant Beaver and in the Santa Clara offshore California fields, [576 feet (176m)] and [1475 feet (450m)], respectively. The wells are producing from 11 inch diameter open hole gravel packed intervals having maximum well deviations of 87° and 84° from the vertical, respectively. Both wells were completed using downhole hardware specifically designed for horizontal (or extremely deviated) wellbore gravel packing. Gravel was placed around the single screen prepack liners using reduced viscosity (±400 cp @ 100 sec1) gravel carrier fluids, low gravel concentrations (3 to 5 ppg) and increased displacement rates (±5.0 BPM).
Rate-Convolved Horner Plot for Analysis of Simultaneously Acquired Flow Rate and Pressure Data
Authors: Tariq S. M. 
Published: December 2007

ABSTRACT
During the last five years, the use of simultaneously acquired pressure and flow rate data in well test analysis has become quite common. The additional measurement of downhole flow rate makes the assumption of constant wellbore storage unnecessary and enables one to perform a more rigorous analysis. Many techniques have evolved for analyzing such data. These include convolution, deconvolution, convolution derivative, and convolution type-curves. In this paper, we present a new technique called the Rate-Convolved Horner plot for analyzing rate and pressure data which offers certain advantages in comparison to other methods. These advantages include: simplicity and analogy to conventional Horner plot, integration of flow period data with shut-in data, better handle on skin, and its adaptability for quick well-site interpretation. Field examples are presented to show the application of this technique to a variety of well testing configurations. The technique presented in this paper is especially suited for the analysis of short duration transient tests, i.e., after underbalance perforating, TCP/DST, closed chamber testing and IMPULSE* Testing because of rapid variations of flow rate in such tests.
Compressive Loading Casing Design
Authors: Kocian E. M. , Mefford R. N. , Hilbert L. B. , Kalil I. A. 
Published: December 2007

ABSTRACT
This paper provides compressive loading design guidelines for the provision of safe, economic casing for any type of onshore well. Compressive loading design is analyzed by looking at the nature of compressive loads, casing compressive failure mechanisms, and load distribution. Field data verifying such analysis is presented. Lastly, recommended procedures and design factors are offered to reach a final design.
Inspection and Certification of Hoisting Equipment for Critical Wells
Authors: Kirkham K. K. , Lowery D. E. , Hays D. P. , Skogsberg J. W. 
Published: December 2007

ABSTRACT
An elevator failed unexpectedly while drilling a critical deep sour gas well. The elevator failed by brittle fracture. After reviewing industry practice, we decided that the minimum standards provided by API on hoisting equipment were inadequate for a few critical wells. This realization prompted us to develop a complete rig hoisting equipment inspection/ certification program for critical wells. On implementing the program, we found that basic materials certification was not routinely available and detailed component inspections were not routinely done on any hoisting equipment. This paper presents our inspection and certification requirements and thè results of several jobs.
A New Approach to Rig Sensors
Authors: Lesage M. , Casso C. G. , Zanker K. J. 
Published: December 2007

ABSTRACT
The traditional image of mud-logging as a low-tech activity is gradually changing. Drilling data, which were not even archived a few years ago, are now sent by satellite to engineers in offices hundreds or thousands of miles away. These engineers need accurate and reliable information to run the sophisticated computer simulations required in modem drilling.
In the harsh economic environment of today, quality data eliminate waste and help prevent severe incidents: the use of MWD torque and WOB to detect cone locking and incipient pipe sticking is now well established.
Finally, reliable data fed into a proper computer system increase rig safety: thousands of factories, refineries, nuclear plants run (generally) safely because a multitude of sensors alert the engineer to possible malfunctions.
The new rig sensors need to be accurate, reliable, intrinsically safe and reasonably priced. Because no two rigs are alike, they need to be versatile and easy to calibrate (or even better self calibrating). Because the life of the crew might depend on them, the sensors need to be able to diagnose themselves.
To fulfill these requirements, the sensors need to be associated with a computer or micro-processor. The advantage of a central computer over a local micro-processor, is that the computer has access to all the data of the rig to decide if an alarm is valid. For example a computer can easily differentiate between a total mud loss and a stop of the pumps.
This paper presents three new sensors which fit at least partially the description above: a flow-out sensor, with an average accuracy of 25 GPM on a fixed rig, a depth system with a proven accuracy of one foot in a thousand feet, and a ‘calibratable’ hookload sensor.
The flow-out is continuously compared to flow-in for kick and loss decisions. We explain in detail how the system is self-calibrating and self-diagnosing, the management of the alarms and the techniques used to detect a developing kick as early as possible.
The depth system automatically feeds the lengths of the pipes added or subtracted to a tally book. It can be compared to the driller's tally to detect wrong entries or the need for a new calibration.
Calibration of the traditional pressure sensor tomeasure hookload is made every year (in good cases) at great expense. This is not satisfactory when the overpull while tripping is close to the limit of the pipes in deep and deviated wells. We describe an alternative sensor which can be straightforwardly calibrated on the rig.
Effects of Gas Cap and Edge Water on Oil Recovery by Steamflooding in a Steeply Dipping Reservoir
Authors: Hong K. C. 
Published: December 2007

ABSTRACT
A numerical simulation study was conducted to elucidate recovery mechanisms and find optimum operating strategies for a steeply dipping, heavy oil reservoir. A model representing a 20° dip reservoir with an updip gas cap and a downdip edge-water was used for the study.
The study showed that gravity drainage of the heated oil is the main production mechanism in steamflooding steeply dipping reservoirs. Steamflood oil recovery for this type of reservoir is strongly affected by gas cap and aquifer pressures. This is because the gas-oil or water-oil contact can move closer to or away from the initial oil zone, depending on those pressures relative to that of the steam zone. High gas cap pressure is desirable because it slows the injected steam rising above the initial gas-oil contact where injected heat is wasted. A high aquifer pressure retards the growth of steam-zone downdip, thereby reducing the steamflood efficiency.
The study further showed that this type of reservoir can best be exploited by: (1) initiating the steamflood as a line drive with steam injection into the oil zone away from the gas cap and edge-water, (2) placing the injector closer to downdip producers than to updip producers in order to distribute the injected heat evenly between the updip and downdip directions, and (3) continuing to operate both updip and downdip producers to capture the displaced, heated oil until an economic limit is reached. Maintaining a high gas cap pressure by injecting a noncondensable gas, if the gas cap volume is finite, is an additional operating strategy for improving steamflood oil recovery from this type of reservoir. If the aquifer pressure is low, infill drilling downdip from the original producer can be used to improve capture of the displaced oil.
Comparative Study of Prepacked Screens
Authors: Harrison D. J. , Johnson M. H. , Richard B. 
Published: December 2007

ABSTRACT
Prepacked screens (gravel pack screens fabricated with gravel pack sand incorporated into the device) are being used more frequently in gravel packed completions. Many types of prepacked screens are available, but little comparative data has been published. This paper is a comparative study of prepacked screen types. Included in the study are standard gravel pack screen, prepacked screens with two different configurations of pipe and wire jackets, and the more recently developed prepacked screens for restricted casing diameters. The prepack screens were tested with consolidated and unconsolidated gravel pack sands. The plugging potential, the blast resistance, and sand control capabilities of prepacked screens are presented. A 20 in. (500 mm) test cell of 7" (178 mm) casing was fitted such that an air or water sand blasting unit could be used to direct blasting sand at the test screens. The tests indicate prepacks with a thin layer of consolidated gravel pack sand can provide insurance against a gravel pack failure should voids occur in the gravel pack. Also, testing indicates little pressure loss will occur through a prepacked screen during production. The prepacks exhibit good resistance to plugging for particle diameters less than 38 microns. Therefore, current filtration practices employed for gravel pack completions are adequate for prepacked screen applications.
An Overview of Reeled-Tubing-Conveyed society Production Logging Capabilities in California
Authors: Harness P. E. , Hansen M. D. , Terzian G. A. , Fowler S. H. , Golino F. J. 
Published: December 2007

ABSTRACT
Horizontal well completions have increased production efficiencies for operators and are challenging service companies to develop new wellbore analysis and maintenance techniques. Reeled tubing has played a key role in the development of horizontal well servicing techniques. Especially important is the ability to run a continuous tubing string through horizontal intervals while the string is under compression.
By installing an electric wireline inside reeled tubing and using the reeled tubing as a transport and placement mechanism, many standard wireline services can be performed in highly deviated and horizontal wellbores, even in live well conditions. Reeled-tubing-conveyed wireline services performed to date in California include production logs, cement bond logs, casing inspection logs, and perforating. Reeled-tubing-conveyed wireline systems have been successfully deployed in California wells with deviations of 90°, over horizontal ramps of 7,200 ft (2,195 m) in length, at depths of 13,900 ft (4,237 m), and with wellhead pressures of 2,000 psi (13,790 kPa).
A reeled-tubing-conveyed wireline system is described in detail and two field examples are discussed.
Analyzing Unstable Flow in Multilayer Gas Lift Wells with an Application of the Inflatable Diverter Flowmeter
Authors: Clark D. G. , Beardsell M. , Cherel X. 
Published: December 2007

Abstract
Downhole flow and pressure measurements monitored in low flow rate gas-lifted wells in multilayer reservoirs offshore West Africa revealed that production from many of these wells was cyclic in nature. This phenomenon, called "slugging", causes bottomhole measurements to oscillate in unstable fashion. The traditional approach used in measuring vertical flow profiles and computing production allocations for the individual zones drained was invalidated as a result.
Inflatable Diverter Flowmeters* were used successfully in these low rate/high deviation/high water cut wells to provide measurements which, when interpreted as discussed in this paper, yielded not only the desired flow profiles but also permeability, skin factor and potential of the individual layers that were monitored. The flowmeter's response pattern under these conditions was verified by comparison against a numerical reservoir simulator model currently used for multilayered reservoir interpretation. The extension of this technique to the analysis of unstable wells is discussed. The results from a successful match between simulated and measured data (achieved via nonlinear optimizations) provided the layer permeabilities, skins and potentials which, in turn, were combined to derive synthetic flow profiles and by layer inflow performance curves.
Two field examples of wells exhibiting cyclic flow behavior are presented. Results compared favorably with those from buildup tests. Based on experience gained from the evaluation of these wells, recommendations are made for modifying data acquisition schemes so as to enhance final interpretation answers.