bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative Evaluation of Aquifer Diversion to Surrounding Wells after Multiple Large Polymer Gel Water Shutoff Treatments
Authors: Turner Ben , Nwaozo Jude , Funston Brad 
Published: July 2010

Abstract
From April through August of 2009, seven producing wells in the Spring Creek field in the Bighorn Basin of Wyoming were treated with chromium acetate crosslinked polyacrylamide in an attempt to reduce water production, lower fluid levels and achieve more drawdown, resulting in improved oil production. The wells were chosen because of their high productivity, high water cut, suboptimal operation because of pump limitations, and in some cases, marginal economics.
The volume of the gel treatments, which were pumped through tubing with a packer above the productive formations, ranged from 8000 bbls to 11,500 bbls depending on the theoretical maximum productivity of each well when pumped off. The Spring Creek field produces out of the fractured Tensleep sandstone, and the fractured Phosphoria carbonate. The main drive mechanism is bottom water, but reinjection of produced water contributes to some reservoir sweep.
After the seven wells were aggressively treated and returned to production, water rates were reduced by 72%, unfortunately oil rates were reduced by 56%. Following the treatments, however, the total oil production for the areas surrounding the treated wells had increased. It is believed that the increase in oil production is attributed to the diversion of the drive water to other unswept parts of the reservoir with higher oil saturation. The large size of the treatments and extent of penetration through the fractures played a significant role in accomplishing this diversion.
In similar wells treated with a smaller volume of gel, water reduction was not as significant, oil loss was not as great, and the increase in area oil production and added reserves was not as observable. This paper quantifies the favorable effects and economics of this larger more aggressive gel treatment strategy.
A Tertiary Steam Flood Strategy Case Study for an Extra-Heavy Iranian Oil Reservoir
Authors: Tehran S. T. , Mohebbi A. , Enayati M. 
Published: July 2010

Abstract
Steam injection in naturally fractured formations has been drawing considerable interest for more than three decades. It is believed that the steam heats the rock, which then undergoes a thermally induced wettability reversal. Hot water can then spontaneously imbibe into the water wet rock matrix, resulting in favorable oil recoveries. In this study, the applicability of steam injection in an oil wet undeveloped Iranian extra-heavy oil fractured carbonate reservoir is discussed. A geological model calibrated with results of a handmade model was used to study the optimum operating conditions under continuous steam injection. It was observed that under this operating strategy in which the main oil production mechanism is heat transfer, steam injection rate and existence of layers which are open to flow, injection and production pattern are directly related to success of the process and because of high viscosity of oil at the reservoir temperature its influences on final recovery is negligible. Initial pressure of the undertaken reservoir is 927 psi at 1700 ft depth. The gravity of the oil is 7.24 °API with viscosity of about 2700 cp at reservoir temperature. This field is a highly fractured carbonate reservoir with 3.6 billion barrel estimated oil in place. It was further observed that during 50 years which this reservoir has been undertaken to study under discussed recently found strategy, crude oil production reaches to more than 900 barrels per day.
Using Regression Analysis to Relate Safety and Environmental Outcomes to Incidence Factors
Authors: Jablonowski C. J. 
Published: July 2010

Abstract
This paper addresses the need for more rigorous quantitative analysis of health, safety, and environmental data. Regression analysis is proposed and demonstrated as a tool to be used within the data analysis function of an operator's safety management system. It is argued that regression analysis can provide incremental value relative to qualitative or basic statistical analysis. A case study is employed to demonstrate how specific hypotheses can be tested in a systematic way. Results from such studies can be brought to bear on operational and safety management policy decisions. As results of such studies accumulate over the long term, resources will be allocated more efficiently and new best practices will emerge.
The Impact of Rotating Control Devices on the Incidence of Blowouts: A Case Study for Onshore Texas, USA
Authors: Jablonowski C. J. , Podio A. L. 
Published: July 2010

Abstract
Rotating control devices (RCD's) are used to provide a closed circulating system. Conventional wisdom suggests that drilling with RCD's improves kick detection and thus fewer blowouts should occur when this equipment and related practices are deployed. Some insurers require RCD's based in part on this perception. However, there is no published analysis that demonstrates a definitive link between the use of RCD's and the incidence of blowouts. In this paper, the authors use regression analysis to test for such a link. The authors find consistent statistical evidence, across a variety of regression models and variable specifications, that the use of RCD's decreases the incidence of blowouts. Future investigations could incorporate additional RCD usage data and perform a definitive benefit/cost analysis, test hypotheses about other potential benefits of RCD's (e.g. preventing drilling problems, increasing general drilling efficiency), and examine performance in other regions (US, international).
Techniques for the Study of Foamed Cement Rheology
Authors: Olowolagba Kolawole , Brenneis Chad 
Published: July 2010

Abstract
This paper presents methods and laboratory equipment that enable a more accurate assessment of foamed cement used to provide zonal isolation in oil and gas wells. The rotating cup and rotor viscometer commonly used to evaluate foamed cement rheology can introduce a high degree of error. Such errors can lead to the conclusion that low-quality ("quality" defined as the percent of foam in the slurry) cement foams have lower viscosities than their base fluids; such conclusions have been reported by other research organizations.
The following attributes of the "bob and sleeve" conventional rotational viscometer are contrasted to those of a three-dimensional (3D) design, referred to as the Fann Yield Stress Adapter (FYSA). Bob/sleeve can exhibit particle or bubble separation. The FYSA provides 3D mixing to maintain a homogeneous mixture of bubbles or particles.Bob/sleeve produces "wall slip," a common problem with two-phase fluids. The FYSA minimizes wall slip.Low rev/min of the bob/sleeve may not create sufficient stress to ensure velocity profile distribution in the bob/sleeve cup, resulting in significant errors. The FYSA provides 3D volume averaging shear-stress/shear-rate regimes.
A key feature of the FYSA viscometer is that it directly measures the yield point (YP) of a fluid; therefore, it does not rely on statistical regression of shear stress vs. shear rate data. It also measures shear stress vs. shear rate for a variety of complex fluids.
The rheology of foamed cement has a direct impact on the hydraulic properties of the slurry. The advantages of applying foamed cement are Increased wall shear stress for better displacement of drilling mud from the annulus and removal of filter cake from the wellbore wallsImproved fluid-loss controlPrevention of gas migration and water influx during the critical gel-strength periodReduced slurry density for protection of weak formations
This paper presents rheology-testing results using the FYSA and contrasts FYSA results with those obtained using the bob/sleeve method.
GEO Information Portal for E&P Enterprises
Authors: Sur S. 
Published: July 2010

Abstract
Effective reporting and readily available analytics play a vital role in the growth of any organisation. With the rise of automation and IT in business over the last few decades, these critical business requirements are addressed though multiple and often complex applications. As a result, today's workforce deals with several significantly complex applications in their daily operations.
This paper discusses the specific business needs of E&P organizations and advances in IT systems that can address these requirements. We note that even as these vital applications cover critical E&P business needs, the inherent complexity in maintaining, administering and using these applications effectively requires users to devote significant effort in managing these applications. We propose a simplistic approach of introducing a common GIS layer for extracting information from these disparate systems. This paper discusses our approach to fulfilling the information needs of most users, by mining information from various transactional and static systems without getting trained in using the myriad contemporary systems. We further discuss the basic building blocks and the complexities of realizing such an approach and how the solution can be further extended for the entire enterprise.
The Effect of Temperature and Oil Viscosity Reduction on Water Imbibition of Diatomite
Authors: Vega B. , Kovscek A. R. 
Published: July 2010

Abstract
Previous studies of imbibition into diatomite reservoir core as a function of temperature have revealed a systematic increase in spontaneous water imbibition leading to increased oil recovery. Forced water imbibition resulted in a trend of possibly decreasing residual oil saturation as temperature increased. These tests, however, were not conducted in a fashion that allows a simple quantification of the fraction of recovery associated with wettability change and that associated with oil and water phase viscosity reduction. The objective of this work is to delineate the relative impacts on core-scale oil recovery due to oil viscosity reduction as compared to wettability evolution during thermal recovery of light-oil from diatomite. Water imbibition tests were conducted with core samples from the exact same depth within a diatomaceous reservoir. The experiments included spontaneous counter-current water imbibition followed by forced co-current water imbibition to residual oil saturation. All tests were isothermal and carried out at temperatures ranging from 45 to 230 °C (113 °F - 446 °F). Non-wetting phases were a light diatomite crude oil and mineral oils viscosity-matched to the crude oil for each test temperature. The wetting phase was synthetic formation brine. Core samples were subject to different pre-test cleaning procedures aimed to preserve or alter the initial wettability of the sample. A core with preserved wettability was used with crude oil as the non-wetting phase. The other core was cleaned and used with the corresponding matched viscosity mineral oil. Increasing temperature resulted in a trend of increased spontaneous and forced oil recovery and lower residual oil saturation for both samples. Wettability shifts with temperature were more pronounced and systematic in the preserved wettability system. The cleaned system displayed lesser changes in wettability at all test temperatures as verified by experimental measurements of the Amott index.
The Effect of Spent Acid on Carbonate Rock Wettability
Authors: Saneifar M. , Fahes M. M. , Hosein R. L. , Hassna B. O. , Hill A. D. 
Published: July 2010

Abstract
This is an experimental study aimed at improving the recovery of spent acid in carbonate gas reservoirs. When acidizing, the spent acid penetrates deeper into the formation beyond the stimulated zone. The spent acid needs to be removed in order to restore the permeability to gas and enhance well performance. One of the most important factors that control spent acid recovery is rock wettability. In this study, we investigate the changes in the wettability of carbonate rocks when invaded by spent acid experimentally. These changes in the wettability are due to the various additives that are added to the acid treatment.
In this paper, we explain quantitatively the effect of wettability on spent acid recovery and we present experimental results on the effect of spent acid on carbonate rock wettability.
Our results show that carbonate rocks are not strongly water-wet; spent acid (HCl) by itself does not change wettability of the rock; some commonly used additives can change the wettability of the rock either towards stronger water-wetting or less water-wetting.
To the best of our knowledge, there is no published data on the effect of spent acid on rock wettability and how that relates to the rate of recovery and its ultimate value.
Successful Application of CO2 Tracer Technology for Surveillance of Gas Lifted Wells
Authors: Shnaib Fathi , Nadar Manickam S. , Sreekumar M. P. , Ponnuvel K.. , Peacock Larry 
Published: July 2010

Abstract
Well surveillance is a key component of production optimization cycle of the gas lifted assets. Even though monitoring of the surface well parameters can give some clues on the downhole gas lift system performance of oil wells, Flowing (pressure and temperature) Gradient Surveys (FGS) in most cases is still required to check the health of the downhole gas lift system and troubleshoot the downhole inefficiencies of well gas lift operations. The FGS has certain level of risk as it involves running electronic memory gauges on wireline in the well at flowing conditions.
An emerging technology using CO2 tracer was implemented as a pilot project in eleven gas lifted wells offshore fields Dubai. The results show that this method is very effective for the quick and reliable determination of lift gas entry points in the well. The method can detect the operating lift depth, detect multiple points of injection and even detect tubing leaks.
It is true that the downhole pressure and temperature data cannot be obtained from tracer surveys. Nevertheless, the technology can be used as an alternate tool to FGS for the following advantages: Minimum equipment hook-up and no need to shut-in or choke the well, means no production loss.Less equipment required for the survey, reduces logistics issues especially in offshore locations.No wireline tools introduced into the wellbore, eliminate well intervention riskSuitable for wells where a FGS is not possible due to well slugging, significantly deviated or with downhole obstruction.Possible to run tracer survey on 3-4 wells on a day if the wells are located at the same platform.
This paper will describe the objectives of the pilot project, the well candidate selection criteria, details of the execution of the survey and interpretation of the results. Practical suggestions for getting the best results from such surveys will also be provided.
Simulation Investigation of Solvent Co-Injection in Vapor and Liquid Phase to Reduce Shale Barrier Impact on SAGD Performance
Authors: Li Weiqiang , Mamora Daulat D. 
Published: July 2010

Abstract
It is well known that shale barriers significantly reduce steam-assisted gravity drainage (SAGD) performance at Athabasca field. An extensive 2D simulation study shows that the flow resistance at the end of shale barriers and the extra heat absorbed by the residual water inside the unproductive shale barrier are the main reasons for the shale barrier effects. Long continuous shale barriers located vertically above or near the wellbore delay production performance significantly.
We investigated potential strategies, including solvent co-injection, top injector application, or a combination of both, to reduce the shale barrier impacts. Solvent in the vapor phase can pass though the narrow flow path at the end of a shale barrier. Meanwhile, as the phase condenses from vapor to liquid, solvent efficiently reduces the flow resistance of the shale barrier. Liquid solvent coinjection can accelerate the near-wellbore flow and reduce the residual oil saturation at the wellbore vicinity. Coinjecting a multicomponent solvent can flush out the oil at different areas with different drainage mechanisms from vaporized and liquid components. Additional injector application at the top of the reservoir results only marginal improvement.
Quantifying the Fate of Hydrate Inhibitor in an HPHT Gas Condensate Subsea Tieback
Authors: Wylde Jonathan J 
Published: July 2010

Abstract
This paper is about an HPHT subsea tieback to a gas-condensate platform. Gas and fluids from three wells are routed through individual in-field flow lines and gather at a subsea manifold several miles from the platform. The fluids pass from the manifold through a pipe-in-pipe pipeline back to the platform.
Industrial methylated spirit (IMS) was the hydrate control chemical selected for the tieback and was used to inhibit the pipeline on a "cold start" after depressurization. There was very little data on the phase-partitioning of IMS, and quantities could end up at the oil terminal where they have a serious effect on processing and product quality.
This paper summarizes the management of using large quantities of IMS (30 m3) to cold start this subsea field. Results from a series of injection trials at the oil terminal have been summarized and show how partitioning of IMS occurs. Further, the paper explains how this proved crucial in risk assessing the impact and use of IMS on the platform. The data has been used to improve the model (CPA equation of state and HYSYS) data sets and details of this have also been included. Extensive sampling exercises performed offshore, when injecting and processing IMS (necessary in order to meet export waiver requirements), are added and lead to details of phase-partitioning behavior through the platform process plant.
Such considerations are rarely made, nor lengths taken to understand the exact partitioning and fate of a chemical when injected offshore, as well as arrival at the terminal. The implications in this instance were significant and therefore the exercise was necessary. The results show that exact quantification is very elusive and that relying on models and standard principles can be misleading and potentially damaging.
Biodiesel as Surfactant Additive in Steam Assisted Recovery of Heavy-Oil and Bitumen
Authors: Babadagli T. , Ozum B. 
Published: July 2010

Abstract
Use of additives to improve the efficiency of thermal heavy-oil and bitumen recovery processes has been studied extensively over the decades. Two common types of additives used in thermal applications, mainly steam assisted recovery, are solvents and surfactants. Commercial use of solvents have setbacks due to their high costs and retrieval difficulties. Cost and stability of the surfactants under reservoir operating temperature and pressure are the major concerns. We propose the use of biodiesels such as fatty acids methyl esters as a surfactant additive reducing heavy oil/bitumen-water interfacial tension in steam assisted recovery processes. Advantages of using biodiesel as a surfactant additive are that biodiesel is chemically stable under the operating pressure and temperature of the reservoir, it causes no harm on bitumen quality and release water chemistry and its use is economically feasible.
We have conducted a series of steam assisted bitumen recovery experiments to clarify the additional recovery potential and efficiency improvement capacity of biodiesel. High pressure steam at 1.8 MPa pressure, 205 °C was used in these tests at a 900 g/h feed rate. The porous media used was a normal grade oil sands ore obtained from a surface mine operation in northern Alberta, Canada. Oil sands ore was packed in a basket and placed in a high pressure cell. Bitumen recovery experiments were performed by spraying canola oil fatty acid methyl ester on oil sands ore at a 2 g/kg-bitumen dosage. These tests show that bitumen recovery efficiency increases over 40%. In another series of tests, tall oil fatty acids methyl ester was injected into a high pressure steam line at a 7.4 g-biodiesel/kg-steam dosage. Because of the solubility of biodiesel in bitumen, the effect of biodiesel on bitumen recovery could not be accurately concluded. Vapor pressure measurements performed on canola oil and tall oil derived biodiesel samples suggest that saturation compositions of biodiesel in steam at 1.8 MPa pressure and 205 °C are at least one order of magnitude higher than the requested biodiesel dosages. Further tests are planned by reducing biodiesel dosages to about 1 g and 0.5 g-biodiesel/kilogram-steam and by monitoring the solubility of biodiesel in bitumen.
Reconfiguring a California Platform for Offshore Crude Dehydration and Water Disposal via Injection
Authors: Frankiewicz Ted , Van Nostrand Bob , Manning Bob 
Published: July 2010

Abstract
Venoco Inc. operates Platform Holly off the California coast near Goleta. To reduce operating costs and GHG emissions, Venoco undertook a program to reconfigure the platform so that oil could be dehydrated offshore and produced water injected into wells directly from the platform. In this paper, the reconfiguration of the platform is described, starting with the production header. The service of several vessels was changed. The production separators were upgraded to provide initial 3-phase separation and allow wet oil to be dehydrated in a new electrostatic treater. Three test separators were removed, an acid surge drum was converted first to a water skimmer and then converted to a test separator, and an oil surge vessel was converted to a water surge vessel/oil skimmer. State-of-the-art internals were utilized in all vessels to improve both performance and capacity. Three PD water injection pumps were installed and three wells were converted to water injection service.
A laser-scan was performed in order to generate a 3D model of the existing platform and to develop the design for the new piping. The 3D model provided guidance for the actual installation of the new treater and identified spatial conflicts. The model facilitated both demolition of old piping and the efficient installation of new piping with a minimum amount of rework and shut-down time. All newly installed systems are in successful operation.