bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pilon Field After 70 Years - Challenge, Strategy and Economic Viability To Continue Developing A Mature Heavy Oil Field Through Available Technologies, Geoscientist and Engineering Practices
Authors: Balza B.A. 
Published: January 2012

Abstract
Over the last 15 years, operators in the oil industry have used new technologies and field strategies, which have brought opportunities for maximizing the Net Present Value. For example, through drilling drainholes or revisiting existing wells, using MWD-LWD techniques for having a better control hitting the target, and Concentric Coiled Tubing practices for cleaning wells up, additional production is gained. This practice has been demonstrated by Lagoven, S. A. in Pilon Field, when it was subsidiary of PDVSA, drilling 69 reentries, horizontal lateral bore of 1200 feet, from 1993 to 1998, with an exceptional performance of the drilled formations for the medium radius application.
How revitalize Pilón Field through drilling new drainholes and also cleaning up potential wells, which essentially are plugged by sand, was the focus of this project. The actual contribution of the field is just over 14,000 BPD and after making part of the reservoir management processes others 19,000 BPD have been projected in the short term through 44 new wells intervention. That process implicated to understand their geological setting checking the geocellular model, recovery mechanism, past reservoir performance and recent fluid flow patterns, wellbore diagram and integrity, allowing to make a prediction of production for the further 10 years.
In addition, economic considerations were carried out considering not only well intervention but also surface facilities in order to deal with the high volume of unwanted fluids. Eventually, sensitivity analyses were done demonstrating that the worse scenario is having oil price lower than $17/bbl. On the other hand, the critical point would be availability of rigs and CCT unit in the market.
Utilizing Lase Drilling: A Step Forward in Environment Protection
Authors: Jegarluei S. Ghadami , Moazeni A. R. , Habibi E. 
Published: January 2012

Abstract
In the recent decades using laser in drilling operations was limited and unreliable in some extent because of the problems in its way and some limitations in its using. These problems cause some uncertainties in using laser and lots of defiance could be seen in front of this technology. But it can be remembered when the idea of replacing cable tool drilling with rotary table drilling was proposed by some researchers there was such kind of resistance. But persisting in their idea caused a revolution in drilling technology by these technology introducers. Drilling mud is one of the basic materials which is used in drilling industry while drilling a well. Also water based mud is less dangerous in aspect of environmental damage but it is unavoidable using oil based mud in shaly formations. Using laser instead of available drilling technologies can replace air with common drilling fluids and reduce environmental damages considerably. Also it can reduce non-productive time due to omission of drill pipe, increasing penetration rate and reducing specific energy significantly. In these paper advantages of laser drilling would be considered in comparison with conventional drilling methods. Also role of laser drilling in reduction formation damage and environmental damage in one of Iranian south west formations would be notified.
Synthesis of Wax Inhibitor and Assessment of Squeeze Technique Application for Malaysian Waxy Crude
Authors: Halim N. , Ali S. , Nadeem M. , Abdul Hamid P. , Mohd Tan I. 
Published: January 2012

Abstract
Highly paraffinic (or waxy) crude oil can cause significant problems in the pipelines due to wax–oil gel blockage resulting from the precipitation of the wax components. Once blockage of the pipeline occurs and flow ceases, the pipeline flow cannot be restarted with the original steady state operating pressure but instead requires significantly higher pressures to restart the flow. Due to this, it is important to maintain the oil at a temperature above its natural pour point.
The incorporation of chemical products known as wax inhibitors and pour point depressant (PPD) reduce the pour point and viscosity of oil. This paper introduces an indigenously synthesized wax inhibitor from the hydrophobically modified polybetaines (zwitterionic) family for treating waxy crude A located in Peninsular Malaysia. The synthesized wax inhibitor had been evaluated as flow improver, crystal modifier and pour point depressant.
The wax inhibitor coded CRODDA-AA, works efficiently since it can reduce the pour point of waxy crude A by 12°C and the viscosity about half of the original value at 1000 ppm concentration, as well as lowering the yield stress by 8 Pa at 51°C. In order to assess the use of the CRODDA-AA wax inhibitor for squeeze applications, a core flood study was conducted to determine its adsorption capability onto formation. A formation damage study was also conducted to ensure that there is no formation damage coupled with the injection of wax inhibitor. It was found that wax inhibitor CRODDA-AA can be retained in the formation up to 88.5% without significant formation damage. As a next step, it is planned to run the core flood and wax inhibitor release tests to refine the design of squeeze treatment.
Study on Gas Channeling Characteristics and Suppression Methods in CO2 Flooding for Low Permeability Reservoirs
Authors: Wang Rui , Lv ChengYuan , Lun Zengmin , Yue Xiangan , Zhao Renbao , Wang Haitao 
Published: January 2012

Abstract
This paper shows the close relation between the displacement effects and reservoir properties in CO2 flooding for low permeability reservoirs. Low permeability reservoirs are characterized by tight matrix, strong heterogeneity and developed fractures. With the increase of CO2 injection rate, the CO2 viscous fingering gets worse in low permeability homogeneous reservoirs. While for low permeability heterogeneous reservoirs, the increase in displacement differential pressure contributes to the enhanced oil recovery in less permeable layers. The moderate increase in effective pressure is conductive to improveing the oil recovery in matrix. The displacement effect and CO2 channeling can be improved through the adjustment of injection-production parameters in CO2 flooding. Additionally, the interaction among CO2, oil and brine can improve the water-oil viscosity ratio. The gas viscous fingering can be weakened. The temporary performance of oil-water emulsion band formed in carbonate water can plug high permeability layers, and the production capacity of low permeability layers can be enhanced. The compound gel system in the sour environment of CO2 can plug large gas-channeling paths, restrict gas channeling and enlarge the sweep efficiency.
Mechanical Earth Model (MEM): An Integrated Study in Low-Fracture-Gradient and Depleted Fields to Improved Cementation (Case Study)
Authors: Sondang Jaka , Irawan Gondo , Sehang Andry , Permana Dian , Wibowo Satrio , Wisanti Lia 
Published: January 2012

Abstract
A depleted reservoir in the Tapian Timur field in South Kalimantan, Indonesia, is located at 1,400-mTVD with a 400-psi formation pressure. Drilling through it presents potential threats to operations, including lost circulation during drilling and cementing and borehole instability. Two wells previously drilled and completed in the area suffered long NPT due to stuck pipe and bad cement bond quality. Even though the field has been explored and developed for 43 years, a thorough study of the reservoir characteristics was never done. Improper knowledge of a reservoir like this one cause’s unnecessary lost time during drilling and poor zonal isolation of the target zone, can potentially jeopardize the economic feasibility of a project.
For this reservoir, a geomechanical study was applied, and a mechanical earth model (MEM) was built. The model utilized multidisciplinary data across the field (drilling and logging data, core, pressure history) to evaluate wellbore stability and improve drilling practices. The MEM study provided key recommendations for the drilling process and cementing operation. Decisions made based on the study include changes in casing point, mud-weight optimization, and utilization of high-performance lightweight slurry with fiber.
A subsequent well drilled in the area applying the recommendation from the study was drilled and completed faster. Cement bond logs from the section also indicated excellent zonal isolation across the reservoir. The recommendations from the study are currently integrated into the standard operation procedures.
Novel Gauge Extension Optimizes Conventional Drill Bits for Superior Performance with Rotary Steerable Systems
Authors: Stroud Daryl , Lines Liam , Barton Steven , Sanchez Hector 
Published: January 2012

Bit gauge length has been a hot topic for several years, particularly when assessing optimal length for rotary steerable systems (RSS). Discussion has not just been about the length; aspects such as geometry, tapering, width, cutting elements, have all complicated the matter further, as well as the fact that different RSS tools require different configurations for optimal balance between steerability, stability, durability, and drillability.
This paper describes a joint engineering approach in identifying gauge configurations for the latest generation of RSS that utilizes point-the-bit technology. The project included systematic testing at a purpose-built, full-size drilling test facility. This has enabled a direct comparison of the directional response, hole quality and drill string vibration to be made for the various gauge configurations tested.
The testing included use of a novel gauge extension stabilizer. This unique stabilizer provides a method of extending the gauge length of the bit on the rig floor, giving a wider variety of bit selection choices for specific applications. The gauge geometry of the stabilizer provides a 360 º continuous circumferential contact with the borehole, thus providing improved borehole quality and reducing vibration.
Field trials proved that the addition of a gauge extender to a short gauge bit can dramatically improve hole quality when used with point-the-bit RSS. The closer gauge hole significantly reduced the severity of downhole vibration and backward whirl. Concerns over lack of steerability, in conjunction with high levels of stick slip and torque, proved unfounded.
This study proves that a short gauge, short length bit, when combined with a gauge extender, can be a suitable replacement for a long gauge bit; affording the improved lateral stability required by the RSS whilst allowing operators the freedom to select a widely available short gauge bit with the correct cutting structure.
Smart EOR Screening, Breaching the Gap between Analytical and Numerical Evaluations
Authors: Moreno Jaime , Gurpinar Omer , Liu Yunlong 
Published: January 2012

Hydrocarbon’s exploration is reaching global frontiers pressuring for near and long term solutions to increase oil production from the existing assets. Field development drivers are shifting towards maintaining a high production plateau while effectively sweeping the reservoir hydrocarbon to maximize recovery. Enhanced oil recovery offers a substantial alternative to improve recovery of green and mature fields by means of enhancing pore level sweeping in the reservoir.
While the principles of EOR schemes are not new; field implementation has been scarce and, as a consequence the physics governing the displacement process have not been completely understood. Highly heterogeneous reservoirs in particular pose a challenge for EOR. Geological features influence the EOR agent advancement and their influence needs to be considered on the early stages of EOR screening. A successful EOR selection requires a detailed understanding of the reservoir governing forces together with the reservoir architecture to maximize reservoir conformance.
This paper focuses on these issues by proposing a new methodology to aid the EOR selection, addressing the influence of vertical and lateral heterogeneity at the early stages of the screening and providing guidance to maximize contacted oil in the reservoir by reconciling the reservoir driving forces and geological architecture. A comprehensive analysis of the present and past reservoir conditions is used to determine the EOR best suited for the reservoir; data mining, optimized numerical and analytical simulations are used to further substantiate the decision and help mitigate uncertainties by incorporating present and past EOR experience during the selection process.
Greener EOR: Employing Cogeneration to Improve the Energy Efficiency of Thermal EOR projects
Authors: Welch Mike 
Published: January 2012

Thermal EOR technologies such as Cyclic Steam Stimulation, Steam Assisted Gravity Drainage and Steam Flood can be extremely energy intensive, requiring the combustion of fossil fuels to produce the steam required, with the resulting emissions of carbon dioxide and other pollutants. Newer technologies such as Solvent Extraction may also require the injected medium to be heated to maximise oil recovery from the reservoir.
EOR projects tend to generate the heat and power required in separate facilities, with the electricity often being supplied from a remote central generation facility. In many cases it may be possible to integrate a cogeneration plant into the EOR process. Using a single facility, a locally available fuel can provide both the power and heat required for the project, therefore optimising global energy efficiency and achieving very high overall fuel efficiencies, usually in excess of 75%, while helping to reduce the global CO2 footprint of the Oil & Gas industry. In most cases the heat produced by a Cogeneration plant is a byproduct of electricity production, but it is also possible to utilise waste heat or waste gases from some processes to produce useful energy.
There are numerous different ways to configure a Cogeneration plant depending on the type of fuel available and the ratio between power and heat required by the project. This paper will examine some of the different Cogeneration configurations and fuel options using Gas or Steam Turbines, or a combination of both, that could be applied to a thermal EOR project.
Gas Turbine combustion can also play a significant role in the overall environmental as well as economic benefits of cogeneration in an EOR facility. The use of a wide range of fuels requiring little or no pre-treatment in a Dry Low Emissions combustion system reduces on-site energy consumption and helps reduce emissions to atmosphere of pollutants such as NOx.
Innovative In-situ Reservoir Stress Test Helped to Manage and Optimize Water Disposal under Fracturing Conditions in South Oman
Authors: Msallati S. El , Hammad K. , Priyandoko P. , Cig Koksal 
Published: January 2012

One of the major fields in the South of the Sultanate of Oman produces oil at 94% average BSW. All produced water is disposed of without treatment into the same aquifer. The disposed water is injected under fracing conditions and takes place more than 200 m below the lower shale (cap rock) in the sandstone (Fig.1). However the failure of the field’s cap rock could result in oil deferment and the contamination of the overlying aquifer; therefore rigorous risk management is strongly required. Figure 1Depth view of the formations in the field. Green arrows show the mini-frac depths.
Several in-situ stress testing (mini-frac) stations were conducted in the field focusing on lower shale and sandstone formations to evaluate the risk of breaking the cap rock and above formations associated with the water disposal. However this was very challenging using the normal ways of testing; hence the stress testing application was conducted with an oil based viscous fluid. The viscous fluid allowed accomplishing the objectives in higher permeability and shale zones. The oil based viscous fluid facilitates initiation of a fracture in highly permeable sandstone formations and reduces the osmosis and plastic behavior effects in shale zones.
The viscous fluid stress testing provides the results required to update the numerical models for each formation by obtaining minimum stress and fracture initiation, propagation, and closure pressures (frac gradients). Moreover the test results will help to build models that can predict fracture growth while injecting water.
This paper will discuss in detail the viscous fluid stress test and how the results can be used to understand the reservoir behavior. Realistic injection forecasts were made possible using commercial fracture simulation software and some analytical and diagnostic methods based on pressure survey and injection volumes history.
Application of CO2 Miscible Flooding on Gao 89-1 Low Permeability Reservoir
Authors: Qin Li Chun , Hailong Li , Yin Xiao Qian 
Published: January 2012

Abstract
Based on a laboratory study, reservoir simulation and pilot test are presented in this paper for CO2 miscible flooding in low permeability with thin interbedded reservoir. At beginning, reservoir description of Gao 89–1 is sited, which gives a full view of three-dimensional geological model of the field. Swelling test has been done to examine the variation of oil volume and viscosity with increase of the pressure. Slim tube test has also been conducted to determine the minimum miscibility pressure. It shows that it is much lower than the formation pressure, which can be implemented readily in the field. And long core flooding experiment has also been carried out to make a comparison of the displacement efficient between water flooding and CO2 miscible flooding. Composition modeling with CMG simulation software is applied to optimizing the flooding parameters and formula selection for Gao 89–1 reservoir. With further studies going on, pilot test has been carried out. And the result shows that the oil production rate is increased from 31 tons to 42 tons with five wells as experimental subjects. This paper demonstrates the application of CO2 miscible displacement technique in low permeability reservoir development and exhibits the advantages and prospects of this technique.
Dare to CHOP: Resources Development Cost Holistic Optimization
Authors: Chan Keng Seng , Chong Danny , Othman Mohamad B 
Published: January 2012

Abstract
Cost of hydrocarbon resources development in Malaysia is escalating. Typical overall unit development costs are now ranging from 30 to 50 $/Bbl. With this trend of cost escalating, marginal fields or remaining reserves from brown fields may not be economically developed.
This presentation is first to demonstrate effective cost saving by reducing well count with case studies in thin oil-rim and compartmentalized reservoirs in Malaysia. It then illustrates the feasibility of further reducing the well construction cost by changing the well design culture and production strategy. This entails designing slimmer holes and having monobore well completion design for gas reservoirs, the application of ICD and ICV for enhance commingle production from multilayer reservoirs rather than the designing conventional but complex multiple-strings completion wells. Significant cost saving can also be achieved by improving drilling and completion efficiency. The idea of setting up minimum performance standards for drilling and completion and the resultant well construction cost will also be discussed.
Cost of constructing conventional offshore surface structure to support the reservoir production is relatively 3 to 5 folds the cost of the associated well construction. For marginal fields, an idea of developing smaller FPSO but with the capability of coiled tubing drilling and completion will also be presented.
This presentation is the herald urging a paradigm change of the way we were in developing our resources and encourages cost saving as an integrated engineering effort involving reservoir engineering, well design engineering, well drilling and completion engineering, and production facilities engineering.
Wellbore Stability Analyses for HPHT Wells Using a Fully Coupled Thermo-Poroelastic Model
Authors: Wu Bailin , Wu Bisheng , Zhang Xi , Jeffrey R. G. 
Published: January 2012

Abstract
A significant portion of non productive time can be attributed to wellbore instability during drilling, in particular for high pressure and high temperature (HPHT) wells. Drilling introduces changes to stresses, formation pore pressure and temperature in the vicinity of a wellbore. These changes are fully coupled and interact with one another. Such coupling effects are often ignored in the conventional approach to wellbore stability analysis. A thermo-poroelastic 2D model recently developed at CSIRO considers the full coupling effect on wellbore stability.
This paper presents a study that uses this newly developed model to analyze the wellbore stability for a HPHT well drilled in the South China Sea. The study well encountered HPHT condition in the 8.5" hole section with a formation pore pressure gradient up to 1.95 SG and temperature up to 155 °C. The objective of the study was to gain a better understanding of the transient pore pressure and temperature effects on wellbore stability shortly after drilling, and to evaluate if conventional uncoupled wellbore stability models are adequate for HPHT wells. The main conclusions from this study are a) coupling effect caused by changes in stresses, formation pore pressure and temperature cannot be ignored for HPHT wells in low permeability formations, such as shales; and b) conventional uncoupled wellbore stability models are inadequate in deriving a reliable mud weight window for HPHT wells in early times for low permeability formations drilled underbalanced, but are adequate for formations with permeability in the orders of microdarcies or higher.
Enhancing Oil Recovery through Application of Ultrasonic Assisted Waterflooding
Authors: Mohammadian Erfan , Shirazi Mohammad Amin , Idris Ahmad Kamal 
Published: January 2012

Abstract
When oil production declines due to low displacement efficiency and/or adverse mobility ratio, enhanced oil recovery methods are required to improve the production. Application of high frequency sound waves (also known as ultrasonic waves) as an unconventional enhanced oil recovery method has been point of interest for some decades. However, despite number of researches on the applications of ultrasonic waves, the influencing mechanisms are not fully comprehended. The aim of this research is to experimentally investigate the effects of ultrasonic waves on recovery of waterflooding and to discuss the mechanisms involved in this process. Series of straight and ultrasonic stimulated waterflooding experiments were conducted on a long unconsolidated sand pack and the oil recovery was measured at the end of the experiments. Kerosene and vaseline were used as non wet phase in the system. In addition to that, a series of supplementary experiments were conducted using ultrasonic bath in order to enhance the understanding about contributing mechanisms. The recovery of waterflooding increased by 2–16% was observed as a result of ultrasonic stimulation. Emulsification and viscosity reduction were identified as main mechanisms affecting improvement of oil recovery by waterflooding. The results of this research are expected to enhance the insight about the mechanisms involved in application of high frequency waves and contribute in wider application of this method for enhanced oil recovery purposes.