bluuebunny/crossref_metadata_2025_split huggingface dataset:
An ESP Lift Reliability Process: Making the Most of Limited Manpower and Field Experience to Promote Field Optimization – Case Study
Authors: Gagner Michael , Wolfe Bryson 
Published: February 2011

Abstract
To optimize production efficiency in a large oil field, engineers must balance their time for troubleshooting production problems among different wells. This is especially true in fields where rod pumps and electrical submersible pumping systems (ESPs) are used for artificial lift.
Typically, engineering time is limited for addressing daily production issues. In many cases where multiple types of artificial lifts are used, 80% of a field's production can come from 20% of the ESP-lift wells: thus the need to keep these higher producing wells operating properly. Unfortunately, downhole ESP operation knowledge is often low compared to rod lift. Consequently, a rod may get proper attention while the ESP may not. The consequences of this can be detrimental in some field environments.
This paper describes key elements of a software ESP management system that boosts an operator's understanding of ESP lift by providing more insight into poor operating conditions than current monitoring systems can provide. Included are potential and present issues encountered during a typical day of operation based on algorithms and automated trending diagnostics. The software management tool can align with existing field management systems to provide the extra knowledge required to keep ESPS operating longer and more efficiently.
The field described in this paper is a CO2/water-flood recovery field. It involves a five-month pilot project where this new ESP management system was established to improve field performance. A detailed description of the process, the issues resolved, and the lessons learned are provided.
Innovative Bearing and Seal Package Improves Rollercone Bit Performance and Reliability
Authors: Day Jeffrey , Yu Jiaqing , Baker Ryan 
Published: February 2011

Abstract
Over the last several years, PDC bits have continued to encroach on traditional rollercone (RC) applications. The expanding PDC envelope has reduced rollercone usage to only the most demanding applications and hard/abrasive formations. Increasingly difficult wellbore requirements dictate that rollercone bits survive more on-bottom drilling/circulating hours with more footage drilled at higher RPM and weight-on-bit (WOB). Additionally, many applications require the use of directional drive systems that apply additional forces on the bit's cutting structure. Additional tool challenges include deep/hot holes, high mud weights, harsh mud chemistry, high temperatures and applications with less than desired solids control.
These hostile down-hole environments contribute to bit damage and can often lead to the failure of moving components, specifically rollercone bit bearings and seals. Failure of any component in the bearing package often results in a catastrophic failure of the entire system, ending the run with the potential of fishing for lost parts. Mud encroachment into the seal is often the reason for bearing failure.
To solve this problem, extensive analysis of field data and dulls was conducted to identify the conditions limiting seal/bearing life. The solution was identified and new bits were developed during field tests. Field testing included a large data set of 28 test runs against 61 control runs, all in the IADC 527-537 range and in the same application. The test results show and improvement in seal life of the test group of 26.9% over the offset data set. Since these results, testing has expanded to four different bit sizes and bit types. This paper will outline the significant time/cost savings to the operator in the test area.
Deconvolution of Pressure and Rate Data from Gas Reservoirs with Significant Pressure Depletion
Authors: Levitan M. M. , Wilson M. R. 
Published: February 2011

Abstract
Deconvolution is a technique for converting the pressure and rate data obtained from a well operating under variable rate conditions into a much simpler form of constant-rate drawdown pressure response function from the same well. However, deconvolution should only be applied to pressure and rate data that result from fluid-flow in the reservoir that is governed by a linear set of equations. In gas reservoirs, the fluid flow problem is non-linear because the gas properties are strongly dependent on pressure. In some specific situations, this gas-flow problem can be linearized by the use of a pseudo-pressure transform which allows deconvolution to be successfully applied to that data. However, there are situations when a pseudo-pressure transform alone does not fully linearize the gas-flow problem and the resulting data will exhibit non-linear behavior caused by the pressure dependence of the gas compressibility. Direct application of deconvolution to such data will produce erroneous results.
This paper presents an enhancement of the deconvolution algorithm that allows it to be used with pressure data affected by a non-linear pressure-dependent compressibility. We discuss the detailed considerations for this enhancement of the deconvolution algorithm and demonstrate its performance on simulated test data exhibiting this non-linear behavior. We also demonstrate the application of this enhanced deconvolution algorithm to a set of pressure data from a gas well fitted with a permanent gauge and covering the first three years of production from that well.
A Comprehensive Model of High-Rate Matrix Acid Stimulation for Long Horizontal Wells in Carbonate Reservoirs
Authors: Furui K. , Burton R. C. , Burkhead D. W. , Abdelmalek N. A. , Hill A. D. , Zhu D. , Nozaki M. 
Published: February 2011

Abstract
Matrix acidizing models have traditionally under-predicted acid stimulation benefits due to under-prediction of wormhole penetration and corresponding completion skin factors in vertical wells. For long horizontal wells drilled in carbonate reservoirs, productivity enhancement is a function of acid placement and effective wormhole penetration. However, prediction of wormhole penetration requires more effective analysis than provided by current industry models. This paper presents results of matrix acid modeling work for horizontal wells and describes a practical engineering tool for analyzing the progress of matrix acid stimulation for cemented and un-cemented horizontal well completions typically employed in carbonate reservoirs.
An integrated flow model has been developed to predict the wellbore pressure profile and wormhole distribution by tracking the movement of the acid in the wellbore and the formation. Analysis of injection rates and pressures during acid treatment provides engineers with a way to determine the varying injectivity and tubing friction as stimulation proceeds. The model presented here can be used as a forward model for analyzing real-time treatment rate and pressure histories and can also be used to review past treatments to improve future treatment designs.
The wormhole growth model is based on Buijse and Glasbergen’s empirical correlation augmented by the effect of formation heterogeneity and scale-up procedures that extend the wormhole geometry and penetration from laboratory flow tests on small cores to field-size treatments.
Application of this modeling shows acid wormholing through carbonate formations can provide significant stimulation resulting in post-stimulation skins as low as −3.5 to −4.0 vs. previously predicted values in the −1.0 to −2.0 range. Using actual field stimulation data, we also discuss key elements to successful stimulation planning and the diagnosis of matrix acid treatments to achieve effective wormhole coverage for horizontal completions in carbonate formations.
Enviromental Management Performance of Subang Field, PT Pertamina EP, Indonesia on Proper Indicator
Authors: Sembiring Indra P. , Mulyono Eka Adhi 
Published: February 2011

Abstract

Introduction
Oil and gas exploration and production activities are faced with major challenge these days, when they deal with HSE issues especially for environmental issues. This paper describe environmental management performance at Subang Field, PT. Pertamina EP, Indonesia based on PROPER indicators as parameters to comply government regulation

Existing Condition
PT Pertamina EP is a state-owned oil and gas company, engaged in managing the upstream oil and gas production through a more manageable exploration and exploitation activities, consists of 18 field that operated all over Indonesia.
Based on Government's Law of Environmental Management, PT Pertamina EP has to manage all of upstream activities, including environmental aspects, especially environmental impact caused by upstream activities.
Government already set up parameters to evaluate company performance of environmental management. The instrument for that purpose is PROPER.
PROPER is an integrated strategy of Ministry of Environment to implement Law number 23 Year 1997 regarding Environmental Management. There are four main activities in its implementation include monitoring of company's compliance, applying transparency in environmental management or public right to know, involving public participation in environmental management and obligation of company in submitting environmental management information.
PROPER consists of 5 (five) categories: Gold, Green, Blue, Red and Black.
Subang Field, is one of field that operated by PT Pertamina EP, located at West Java. The average of oil production from this field is 15.000 bopd. At 2009 Subang Field achievement for PROPER is Green. It has applied successfully not only government's environment regulation but also good relationship to community around Subang Field.
To achieve PROPER Green category, Field Subang has utilized and managed environmental parameters such as: Waste managemet system (water, emission, and hazardous and toxic material)Implement ISO 14001Energy conservationCommunity development.
The result shows that Subang Field had committed to implement environmentally friendly for all of activities which green process give some advantages for nature resources and community.
Joint Inversion of Temperature and Pressure Measurements for Estimation of Permeability and Porosity Fields
Authors: Duru Obinna O. , Horne Roland N. 
Published: February 2011

ABSTRACT
The acquisition of temperature measurements from wells using downhole devices such as Distributed Temperature Sensors (DTS) and Permanent Downhole Gauges (PDG) is becoming a common practice in the industry. Temperature data acquired continuously at the perforation sandface show transients that may contain information about the characteristics of the producing formation, presenting an opportunity for the combination of flow and heat transport models in reservoir characterization. The physical model for temperature distribution in a reservoir during production shows a strong dependence of temperature on the porosity distribution. The dependence of this model on permeability is weakly linked to flow through convection. On the other hand, the model for flow is more strongly dependent on permeability than on porosity. These models are coupled through the dependence of the heat model on flow velocity, and the dependence of the flow model parameters on temperature.
In this work, the heat and flow models were inverted jointly to obtain an estimate of the permeability and porosity fields in a synthetic reservoir, using combined quasilinear Bayesian inversion methods and Ensemble Kalman Filter (EnKF) for data assimilation. A first posterior mean and covariance of the log-permeability and porosity fields were found using the first set of data and the quasilinear inversion approach (similar to the maximum a-posteriori probability MAP estimate). The ensembles in EnKF were then obtained as conditional realizations using these statistics. The production data (bottomhole pressure and production rates) and temperature measurements were then jointly assimilated with each advancement in time, to obtain log-permeability fields that compared favorably with the true permeability fields, and porosity fields that also compared favorably with the true porosity field.
Also, it was found that the inclusion of temperature measurements improved the resolution of the estimates of both porosity and log-permeability in the test cases, compared to using only production data. Particularly, the porosity fields showed marked improvement with the addition of temperature measurements. The results demonstrate that temperature measurements that are now routinely obtained in producing fields are a potential source of relevant data for constraining characterization of heterogeneous reservoirs.
Numerical Simulation on Three Layer Dynamic Cutting Transport Model and Its Application on Extended Well Drilling
Authors: Wang Zhiming , Zhai Yujia , Hao Xining , Guo Xiaolei , Sun Lili 
Published: February 2011

Abstract
Hole cleaning is one of the key issues in extended reach drilling, the thickness of cutting bed monitor and control is the critical technique which urgent to solve. Based on solid-liquid flow mechanics, considering actions between the layers, slip between solid and liquid phase, and rotation of drill pipe, a three layer dynamic cutting transport model was developed, staggered mesh and Stability Enhancing Two Step method were adopted for the simulation. The influence factors of the thickness of cutting bed were analyzed, ECD with variable cutting bed can be accurately predicted, by compare the measured ECD with the theoretical value, the thickness of cutting bed can be monitored, and this technique has been successfully used in the oil field of South China Sea.
The research results show that high angle hold segment is the most difficult segment for cutting transport. The pump can not reach the minimum flow rate for keeping the hole cleaning. Low viscosity drilling fluid, high flow rate and drill pipe rotation should be adopted, and when the thickness of cutting bed exceeds 10%, flushing method must be used to remove the cuttings, the recommended flushing period is 150m. By this model, the dynamic process of cutting transport during drilling and flushing can be simulated. Giving a guideline to the design of hydraulic parameters, and offering an effective field method to monitor and control the hole cleaning in extended reach well.
The Use of Model Predictive Control for Asset Production Optimization: Application to a Thin-Rim Oil Field Case
Authors: Van Der Linden Ruud , Leemhuis Anton 
Published: February 2011

Abstract
Increasingly the upstream oil & gas industry is using active flow control (e.g. feedback loops) or passive flow control (e.g. passive ICD) technologies to optimize asset production. They are used, for example, to commingle production, stabilize production in case of water or gas breakthrough, and to mitigate the effect of slugging in wells. While the merits of such flow control technologies are becoming clear, so do their limitations.
One main limitation of using traditional flow control technologies is that, in the presence of complex and changing process dynamics, it is difficult to come up with a controller design that optimizes asset production. Advanced control, specifically Model Predictive Control (MPC), is widely used in the industry to optimize complex downstream processes. In this paper we will start to explore the merits of MPC for upstream applications by means of a realistic test case of a thin oil rim that suffers from gas breakthrough. In the paper three aspects of MPC will be explored into detail.
Firstly, we take a look at the dynamic process models, which lie at the basis of MPC. In MPC the dynamic model is used to compute control actions that optimize the future behavior of the production process. In order to do this, the model has to be sufficient accurate and needs to have a computational burden that allows for real-time optimization. We will discuss how a mixture of physical modeling and data driven models may be used for this purpose.
Secondly, we give concrete examples of such fast dynamic models for the production process of the thin oil rim case. The models describe the dynamic behavior of the gas cone in the reservoir, as well as the effect that gas breakthrough has on well performance. Using such a model, we will evaluate 2 different thin oil rim production strategies that are based on downhole and topside flow control.
Thirdly, we develop a production strategy using the MPC framework. In this approach the dynamic well-reservoir model is used to determine optimal settings of wellhead and ICD valve positions that optimize production. This advanced production control production strategy is benchmarked in terms Net Present Value (NPV) and barrels produced, and compared to cases that use only conventional feedback wellhead flow control. Production improvement in oil production over the first 1.5 years is 17% in the test case.
Since beginning of the 1990's, starting in refineries and base chemical plants, MPC has become the standard advanced control methodology in downstream industries, putting more process knowledge (models) into production control and giving rise to optimal production. A similar development may be expected in the upstream industry. As the paper shows MPC has the potential for bringing real-time production optimization a step closer.
A New Pressure-Rate Deconvolution Technique Based on Pressure Derivatives for Pressure Transient Test Interpretation
Authors: Onur Mustafa , Kuchuk Fikri J. 
Published: February 2011

Abstract
In this paper, we present a new deconvolution method that removes the dependency of the deconvolved constant-rate drawdown responses to the initial reservoir pressure. As is well known, particularly the late-time portions of the deconvolved responses from the recent pressure-rate (p-r) deconvolution algorithms are dependent on the initial reservoir pressure. A small error in the initial reservoir pressure could make a significant difference in the late-time portions of the deconvolved responses that can easily lead to an incorrect interpretation model, particularly misinterpretation of the boundaries. The new method presented is based on pressure-derivative data rather than pressure data that are used in all published deconvolution algorithms. Using pressure-derivative data in deconvolution leads to a nonlinear least-squares objective function that is different from those used in the earlier deconvolution methods and eliminates the dependency of the deconvolved responses to the initial reservoir pressure. Hence, the new method minimizes incorrect interpretation due to an error or uncertainty in the initial reservoir pressure.
We apply the new method to both simulated and field pressure-transient data sets. The results show that the new method offers a significant advantage over the earlier deconvolution methods for pressure transient test interpretation in cases where the initial reservoir pressure is unknown or uncertain.
Refracs: Why Do They Work, and Why Do They Fail in 100 Published Field Studies?
Authors: Vincent M. C. 
Published: February 2011

Abstract
A database has been compiled and analyzed, summarizing more than 100 field studies in which restimulation treatments (hydraulic refracs) have been performed, along with the production results. Field results demonstrate that refrac success can be attributed to many mechanisms, including:
– Enlarged fracture geometry, enhancing reservoir contact – Improved pay coverage through increased fracture height in vertical wells – More thorough lateral coverage in horizontal wells or initiation of more transverse fractures – Increased fracture conductivity compared to initial frac – Restoration of fracture conductivity lost due to embedment, cyclic stress, proppant degradation, gel damage, scale, asphaltene precipitation, fines plugging, etc. – Increased conductivity in previously unpropped or inadequately propped portions of fracture – Improved production profile in well; preferentially stimulating lower permeability intervals [reservoir management] – Use of more suitable fracturing fluids – Re-energizing or re-inflating natural fissures – Reorientation due to stress field alterations, leading to contact of "new" rock
Although less frequently published, unsuccessful restimulation treatments are also common. Documented concerns illustrated in this paper include:
– Low pressured, depleted wells (especially gas wells) posing challenges with recovery of fracturing fluids – Low pressured or fault-isolated wells with limited reserves – Wells in which diagnostics indicate effective initial fractures and drainage to reservoir boundaries – Wells with undesirable existing perforations, or uncertain mechanical integrity of tubing, casing, or cement
This paper will explore the common problems that lead to unsatisfactory stimulation, or initial treatments that fail over time. Guidelines for evaluating refrac candidates and improving initial treatments will be reviewed. The paper summarizes restimulation attempts in oil and gas wells in sandstone, carbonate, shale and coal formations. This organized summary of field results and references will provide significant value to readers evaluating or designing restimulation treatments.
Portfolio Management for Strategic Planning and Operational Optimization
Authors: Back Michael J. , Guercio Cesar 
Published: February 2011

Abstract
Portfolio management has become a mainstream discipline to support investment decisions and capital allocation plans for the oil and gas industry. With more than 70% of the top 50 oil and gas producers companies in the world applying it, the scope and reach of the subject is of vital importance.
The aim of this study is to understand how portfolio management is applied in strategic planning and operational optimization, and how the combination of these exercises allows the strategic guidelines to permeate operational decisions.
The first part of the study covers the best practices for the application of portfolio management when tackling strategic planning. Which are the critical business issues the exercise resolves, how to model the corporate long-term direction through measurable KPIs, and what key objectives companies pursue when allocating strategic capital.
The second section provides some specific examples of ways in which portfolio management theory can resolve operational issues such as rig scheduling optimization, key human resources constraints, and facilities management optimization. The third section analyzes how the output of both exercises logically merges into a solid operation aligned with the company's strategy.
The main outcome of this analysis is the definition of a framework that defines the most efficient way to materialize long-term strategic directions as day-to-day operational guidelines, creating an efficiently aligned organization. Efficiency of the planning process will be explored.