bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Approach to Model Hysteresis and Its Impact on CO2-EOR Processes with Mobility Control Strategies
Authors: Beygi Mohammad R. , Delshad Mojdeh , Pudugramam Venkateswaran S. , Pope Gary A. , Wheeler Mary F. 
Published: April 2013

Abstract
Mobility control methods have the potential to improve coupled enhanced oil recovery and CO2 storage (CO2-EOR). There is a need for improved three-phase relative permeability models with hysteresis including especially the effects of cycle dependency so that more accurate predictions of these methods can be made. We propose a new three-phase relative permeability model with hysteresis applicable to different fluid configurations in porous medium under different wettability conditions. The model also includes compositional effects. Three-phase parameters are estimated based on saturation-weighted interpolation of two-phase parameters. The proposed hysteresis model is an extension of the Land trapping model but with a dynamic Land coefficient introduced. The trapping model estimates a constantly increasing trapped saturation for intermediate- and non-wetting phases. The model overcomes some of the limitations of existing three-phase hysteresis models for non-water wet rocks and mitigates the complexity associated with commonly applied models in numerical simulators. The model is validated using multi-cyclic three-phase water-alternating-gas experimental data for non-water wet rocks. Numerical simulations of a carbonate reservoir with and without hysteresis were used to assess the impact of the saturation direction and saturation path on gas entrapment and oil recovery.
A Successful Optimization Case of Drilling and Completion Operations Through Management Tools and Strategies
Authors: Silva Oscar R. , Silva Guden O. , Valderrama Luis I. 
Published: April 2013

Abstract
Sometimes, drilling optimization of an oil well does not come from a new technology or a new drilling tool, but instead, it may come from something as simple as "putting the house in order". This was the particular case of Castilla Field in Colombia in 2010–2011, where people had believed that all the drilling solutions were already applied. This paper shows how the drilling and completion (D&C) optimization of Castilla field was performed. The main problems were identified, and a model of 5 management strategies was implemented to reduce the D&C timing. The strategies of the model were applied under the following objectives: constant measuring, evaluation and monitoring of drilling indicators; Support field operations with strong drilling engineering planning criteria; Establish only one communication line through the office drilling engineer in charge of the project; Establish short, medium and long term planning and strategies, and then link them together as function of the Technical Limit "TL", and subsequently as an HSE function.
The initial evaluation was focused in four main areas: time savings & time to optimize, management indicators, human resources, and drilling operations characterization. The leader of the field has changed the current roles of the engineer in charge of the well from a logistics role to a genuine drilling engineer role. The short, medium and long term vision was applied throughout the well, well pad and campaign in advance. The slogan "Drilling the limit is not hurried up" was created. The technical limit (TL) goal was reached. The D&C times, and therefore costs, were reduced by up to 32% per year. Savings greater than USD50 million dollar per year were accomplished. The 2010 trial of Castilla field became the model for the rest of fields that are part of the company portfolio.
The degree of field optimization responds to the same extent at the level in which the gaps are found. It is believed that, as well as this model was applied successfully to other fields within the company, it also might also be applied to others companies. This paper resumes a model of 5 management strategies needed to purge and cure some bad habits that are against the D&C optimization in a field.
Application of Solvent Alternating SAGD Process to Improve SAGD Performance in Athabasca Bitumen Reservoir
Authors: Souraki Y. , Ashrafi M. , Ghahfarokhi A. Jahanbani , Torsaeter O. 
Published: April 2013

Abstract
Canada, Venezuela and United States contain the largest portions of heavy oil and bitumen resources throughout the world. The problem associated with this type of resource is very viscous fluid flow. The EOR methods applied to heavy oil reservoirs are mainly based on viscosity reduction processes such as heating the reservoir and solvent injection. Heating, in the form of hot water flooding, steam injection and in-situ combustion dramatically reduces the viscosity of heavy oil and bitumen, but it has green house gas (GHG) emission problems. Diffusion of solvents in heavy oil makes it lighter and therefore mobile and producible via production well. Diffusion of solvent is a very tardy process while time is very important in oil industry and any delay results in extra costs. Recently, hybrid methods like solvent and steam co-injection, steam alternating solvent injection (SAS) have been introduced to solve the mentioned problems, while benefiting from the advantages of heat and solvent.
Several simulation studies were performed to evaluate and compare the performance of steam assisted gravity drainage (SAGD) and steam alternating solvent (SAS) processes. Athabasca bitumen reservoir properties were used. Effects of some reservoir and fluid parameters such as thickness, porosity, vertical to horizontal permeability ratio and viscosity were assessed and compared for both processes. Experimental viscosity data of Athabasca and Cold lake bitumen were applied to evaluate the viscosity effect. In addition, sensitivity analysis was carried out on injection time intervals of solvent, solvent type and concentration.
Results revealed high recovery of bitumen and appropriate steam-oil ratio (SOR) for both processes. However, SAS showed better performance using hexane as a solvent. Lower porosity, vertical to horizontal permeability ratio and thickness resulted in higher SOR for SAGD process while they had no major effect on SAS. Higher concentration of injected solvent resulted in faster recovery performance and lower SOR. Pentane and heptane were used as alternatives for hexane to investigate the impact of the selected solvent. They divulged almost the same results as hexane. Different injection intervals of 3, 6, 9 months and a year were also studied and the analogous results were obtained.
Solar-Generated Steam for Heavy-Oil Recovery: A Coupled Geomechanical and Reservoir Modeling Analysis
Authors: Agarwal Anshul , Kovscek Anthony R. 
Published: April 2013

Abstract
The use of solar thermal steam generation for heavy-oil recovery has the advantage of reducing carbon dioxide emissions, as well as offsets the cost variability of steam generation due to fluctuations in natural gas prices. Daily cyclic fluctuations in steam injection rate associated with sunlight hours, along with hydrocarbon production and heating/cooling of rock cause changes to reservoir stress. This paper focuses on the dilation and compaction behaviors associated with continuous but variable-rate solar generated steam injection. Our approach integrates geomechanical models with the reservoir simulation model. The challenge with integrating geomechanics with reservoir models is to find accurate and sufficient data for stress field and orientation, dilation and compaction pressures, and the fracture pressure for the formation.
We evaluate the viability of a solar thermal steam generation system with natural gas back-up for thermal enhanced oil recovery (TEOR) in heavy-oil sands that includes geomechanical coupling with the reservoir. Coupled reservoir-geomechanical simulation runs with continuous variable steam injection were compared with the base-case uncoupled Tulare Sand steamflood project. Sensitivity analyses for dilation parameters were studied to understand their effects on the overall oil recovery and breakthrough times. Significant pore pressure variation to trigger compaction was not observed for reasonable day-time injection rates of up to 1000 BBL cold-water equivalent (CWE)/d in high permeability formations. The injection pressures were maintained much below the fracture pressure of the formation in all cases. To summarize, a solar thermal steam generation approach for thermal enhanced oil recovery is a promising technique for supplementing steam generation in areas with large solar insolation.
Extracting IF-THEN Rules from Numerical Data using Wang-Mendel Methods
Authors: Hao Minshen , Mendel Jerry M. 
Published: April 2013

Abstract
Knowledge and experiences are extremely important in the petroleum field. Most of the knowledge is in some expert's mind and it is not easy to validate and use it automatically.
In this paper, we introduce an approach to extract linguistic IF-THEN rules from numerical data. These kinds of rules are not only easy to implement in intelligent systems, but are also human-understandable. A soft clustering algorithm, the fuzzy c-mean (FCM) algorithm, is used to determine the MFs of the linguistic terms for each variable. Then, the Wang-Mendel (WM) method and two of its variants are applied to some historical data to extract IF-THEN rules. Finally, the generated rules are compared and validated using the given data.
Application of Toyota's Principles & Lean Processes to Reservoir Management: More Tools to Overload the Toolbox or a Step Change in Our Business?
Authors: Allan Malcolm E. , Gold David K. , Reese Dyke W. 
Published: April 2013

Abstract
Aera Energy LLC was formed in 1997 to be a low cost operator and producer in California. However, the low oil price in 1998-1999 forced an examination of all operations in the office and in the field. Cutting costs, better timekeeping, or reducing the scale of operations would not be sufficient without a step-change gain in efficiency. This step-change gain came from using principles and concepts developed in the automobile and construction industries. Toyota's twin pillars of just-in-time production and the ability of anyone to stop production rather than pass-on defects, coupled with level-loading of work processes, and reducing waste were introduced. Toyota's principles were enhanced by the addition of Last Planner concepts developed for the construction industry. When both were implemented for reservoir characterization and reservoir development work, significant process improvements resulted. The resulting improvements are now being used throughout the company to improve quality by removing waste and reducing errors, to measure processes, and to improve cycle times.
The unconventional diatomite reservoirs and oil sand reservoirs at the giant Belridge field produce 63,000 BOPD from 5,200 producing wells and 2,000 injection wells. The many drilling, completion, and workover rigs have a constant appetite for new wells. To maintain production and cost targets, everything in the office has to run reliably and efficiently at all times, plus support field operations.
Different aspects of Toyota's principles and Lean manufacturing are illustrated using reservoir characterization project work, day-to-day reservoir surveillance, and the development work needed to plan and schedule new wells. The processes and projects typically have multiple customers and suppliers—internal and external. Everyone, including knowledge workers, needs to work as a single system with a manufacturing mentality and to strive for continuous improvement. Customers of the knowledge work supplied by the geoscientists and reservoir engineers have benefitted greatly from the introduction of the Lean processes and the resulting smoother and more effective work flows. In 2011, the Development team's Lean activities were recognized by the Association for Manufacturing Excellence, and the team received the Manufacturing Excellence Award that recognizes "continuous improvement, best practices, creativity, and innovation."
The oil industry has a reputation of being slow to adopt new technologies and techniques. However, a Lean Manufacturing mentality introduces new ideas and ways of performing knowledge work that may change this paradigm while contributing to the bottom-line with reduced cycle-time and improved quality. A significant additional benefit is that geoscience and engineering professionals can spend more time doing creative work and less time fixing problems or reacting to system upsets—all while reducing waste.
A New and Practical Oil Characterization Method for Thermal Projects: Application to Belridge Diatomite Steam Flood
Authors: Zhang L. , Pieterson R. , Dindoruk B. , Stoffels P. , Fan Y. 
Published: April 2013

Abstract
Most of the oil characterization approaches for thermal recovery are designed for heavy oils at moderate temperatures where oil can be represented in very simplistic ways (i.e., ‘gas’ and ‘oil’). However, when oil is exposed to very high steam temperatures (i.e. 550°F), and/or the oil is lighter than the classical range defined for heavy oils and is exposed to wide spectrum of thermal effects such as distillation of the lighter ends, the conventional methods representing the interaction of steam and the in-situ fluids is not accurate. In many cases, we have to first evaluate the quality of the data, and then represent the average behavior with a single most likely fluid model per reservoir segment (plus other scenarios, as needed) to simulate the production performance. There is a need to develop a streamlined approach to bring such data into industrial simulators in a practical way.
In this study, we have developed a fit-for-purpose approach to generate a consistent PVT model over the whole reservoir, reflecting both pressure and temperature changes through the entire oil accumulation. The model represents the oil viscosity for wide spectrum of temperatures, from reservoir temperature to steam temperature (thermal process range). A systematic lumping scheme enables conversion of the characterized PVT model for numerical simulators with the minimal number of pseudo-components while still capturing the essence of thermal physics. To our knowledge, there has been no systematic study of this nature in the literature available yet.
We have tested the above approach in the Belridge Diatomite steam drive project. The study confirmed that steam flood incremental oil production in light oil reservoir is sensitive to the component lumping scheme because of distillation of the lighter ends. We also found that a five component PVT model, representing the physics in ‘fit-for-purpose’ dynamic simulation, best compromises between minimal number of components and physical description of the light oil behavior.
An Experimental Investigation of the In-Situ Combustion Behavior of Karamay Crude Oil
Authors: Zhao R. B. , Chen Y. X. , Huang R. P. , Castanier L. M. , Kovscek A. R. 
Published: April 2013

Abstract
In-situ combustion (ISC) is an effective thermal recovery process that provides an alternative to steam injection. Air is injected into a reservoir to oxidize a small portion of the hydrocarbons present thereby generating heat and pressure that enhance recovery. ISC suffers from fewer limitations than steam injection, but is not applied widely. One factor that has limited application of ISC is the difficulty of evaluating ISC candidates in the laboratory to obtain critical information such as crude-oil oxidation kinetics, combustion front propagation, and the burning qualities of various crude-oil components.
The Karamay Field (Xinjiang, China) has crude oil that is roughly 12.0°API and is a potential candidate for ISC. We have conducted a screening study to evaluate the likelihood of the success of ISC in Karamay. Questions of interest for Karamay include the fraction of the crude oil that is converted to fuel and the particular crude-oil components that become fuel for ISC. To investigate ISC properties of the oil, true boiling point fractions were collected from Karamay crude oil and the kinetics of oxidation of each fraction in porous media were measured using ramped temperature oxidation (RTO). The isoconversional approach is used to interpret the RTO results of each boiling point fraction. The approach obtains the reaction kinetics for a given rock/oil sample at identical reaction extent from multiple experiments with different heating rates.
The 500+°C boiling point fraction presents reaction kinetics most similar to the whole crude oil indicating that the crude-oil components in this fraction contribute the most to fuel production. Reaction kinetics of the whole oil appeared to be favorable for successful propagation of a combustion front. This prediction was validated by conducting displacement tests in a 1 m long combustion tube using reservoir sands. The Karamay crude oil demonstrated significant in-situ upgrading as a result of ISC. The initial gravity was 11.8 °API whereas the average gravity of the produced oil was 19.3 °API. Importantly, our results add to the knowledge base of both conditions for successful ISC as well as significant upgrading.
Drilling Challenge of Unstable Hole: Condition in Kilo Field: A Case Study in Southeast Asia
Authors: Tobing Jerry , Tanjung Erwindo 
Published: April 2013

Abstract
One of the drilling challenge in Kilo Field of Offshore North West Java Indonesia is unstable hole condition. The critical formation is named Main Massive with the dominant clay-rich shale lithology. The unstable hole had caused stuck pipe, casing delays, loss of expensive tools in the hole, and undesirable sidetracks.
Recently, there were 2 wells was drilled in Kilo Area. Based on the offset wells data drilled from this platform, there were some wells running in normal operation and the others were having unstable hole problems. All of the offset wells were using dispersed water based mud system in which generally, the drilling operation of those offset wells could be managed until casing run to the bottom. The recent 2 wells encountered unstable hole problem are KKNA-5 and KKNA-3ST development wells.
KKNA-5 was designed to drill from the new slot using the same mud system as the offset wells from surface until intermediate section. In production section, mud system was changed to inhibited polymer referred to laboratory test result of cutting samples from surrounding area. However the unstable hole problem was still happened causing stuck pipe and BHA lost in hole.
KKNA-3ST as reentry well also encountered same problem. The production section was drilled using inhibited mud system; however the unstable hole was uncontrolled while running the casing. The casing was parted and left in hole. The sidetrack drilling was decided using previous dispersed mud system, but again the casing was set shallower due to unable to run until casing point.
Preliminary root-caused analysis led to the mud material quality. However, following other drilling wells in other fields was drilled without similar drilling problem in Kilo area, which mean the uncertainty or material quality was diminished. The deeper engineering analysis was also conducted without carrying out unstable hole problems.
This field case study presents a new drilling challenge in Kilo Field. Further drilling study especially related to time-dependent wellbore instability shall be conducted, considering drilling operation of some offset wells was running smoothly. The integrating geomechanic study with drilling fluid design shall mitigate unstable hole problems in this area.
California Department of Conservation's Division of Oil, Gas, And Geothermal Resources: Orphan Well Program
Authors: Hesson, P. E. Bruce H. 
Published: April 2013

Abstract
The California Department of Conservation's Division of Oil, Gas, and Geothermal Resources (Division) supervises the drilling, operation, maintenance, and abandonment of wells so as to prevent, as far as possible, damage to life, health, property, and natural resources.
One of the Division's many programs involves orphan well elimination. A well is orphaned when the operator is defunct or when the Division determines through the formal order process that it is deserted. The California Public Resources Code allows, with the consent from the mineral rights owner and the Division, a different operator the opportunity to evaluate an orphan well's potential and to acquire ownership. In cases where an orphan well is not acquired by a viable operator and has been determined to be a public nuisance or hazardous, the Division can contract to have it permanently plugged and abandoned. The Division is funded through an assessment on oil and gas production, which also includes funding for the abandonment of orphan wells.
This paper will discuss the California Public Resource Codes (PRC) related to orphan wells, the process to declare a well orphaned, the procedures to allow an operator to acquire an orphan well, abandonment funding, the selection process for wells to be abandoned, State competitive bid abandonment contract requirements, abandonment project planning and oversight, several case studies, and the Division's orphan well program accomplishments.