bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spoolable Connector Allows Coiled Tubing Operations Offshore India
Authors: Effiong G. , Dean G. , Nayak S. , Satyarthi R.S. 
Published: January 2010

Abstract
Available footprint on offshore platforms can be a significant challenge for Coiled Tubing (CT) operations. Many times a smaller CT unit is deployed for work that would be faster and operationally easier with CT of larger diameter. Often the platform’s crane capacity dictates the size of CT to be used, which in turn reduces the working envelope of the CT.
Some wells offshore India are completed horizontally and require intervention utilizing larger sizes of CT in order to gain horizontal reach and manipulate sliding sleeves. When CT is used for these operations, the weight of the CT reel itself is critical to the effectiveness of the overall operation and requires proper management. Traditional methods of managing / reducing CT reel weight involve spooling the CT string from a boat to the platform or joining CT sections by butt welding them together on the platform. Bringing the required length of CT onboard in two or more sections and joining them together utilizing the spoolable connector provides significant benefits over the traditional methods. The use of just one spoolable connector can reduce the maximum CT reel lifting weight by typically 30-40%, while increasing the CT size easily by one or two gauge sizes.
This paper describes the results of a feasibility study performed to address typical challenges and presents actual case histories in which a spoolable connector was used to connect two CT strings. Required equipment was built and mobilized so that two separate strings could be joined on the platform with the aid of a connecting jig. Several trips were safely performed without the need to change the spoolable connector. Specific benefits of the spoolable connector over the traditional methods are explained. Methods to monitor the usable life of the spoolable connector while tripping in and out of the well will also be discussed, as well as new developments currently underway.
Dry-tree Support Semi-Submersible for Drilling and Production From Deepwater of East Coast India
Authors: Srinivasan Nagan , Sundaravadivelu R. , Selvakumar R. , Kaundinya V.P.K. 
Published: January 2010

Abstract
The most reliable floating structure for the unexpected storm conditions of east coast India deepwater is presented in this paper. Dry-tree support due to very low heave response in 100 yrs return strom attracted this vessel solution to be cost effective in ultra deepwater. Several advantages are inbuilt including self installation of the vessel. The key design features that would enhance the applications of the semi-submersible design for deepwater are vessel motion characteristics, heave natural period, high air-gap, large deck-area, large deck pay-load, reduced mooring load, large riser pull-down load, feasibility for dynamic positioning, self-installation, quay-side top side integration and float-over installation. This paper presents the design of dry-tree support semisubmersible for drilling and production from deepwater of east coast India. The displacement of the vessel is 82500T, payload is 15000T, free board is 19.85m and the keel tank size is 91.5m by 91.5m by 6.1m. The ballast in the keel tank is 28000T.The hydrodynamic response of the vessel obtained by the experimental study for the retracted condition is used to validate the numerical results. The numerical study on the dry-tree submersible with keel tank in retracted (draft=39.62m) and telescopic condition (draft=65.25m) is carried out and the results are used to demonstrate the application of dry-tree support semi submersible for deep waters of east coast of India.
Middle East Field Water Production Mechanisms
Authors: Al-Ghanim Jassim A. , Al-Nufaili Subhi A. 
Published: January 2010

Abstract
The control of water production has always been one of the most critical challenges in Middle East oil fields. Good evaluation of water production mechanism results in a proper control on water, since there is a different job design for different mechanism. In general, water coning and/or multilayer channeling is the most production problem mechanisms in Middle East oil fields. The purpose of this work is to apply water control diagnostic plots technique to identify excessive water production mechanism.
This method was applied for wells in Middle East sandstone oil reservoirs using actual production history data to generate log- log plots of WOR (water oil ratio) and dWOR/dt (simple time derivative of water oil ratio) vs. time.
The plots were found to be effective in differentiating whether the well is experiencing water coning (negative slope) or multilayer channeling (positive slope for the time derivative of water oil ratio curve).
The diagnostic plots applied in this study provide a handy method for quick evaluation of excessive water production mechanisms in order to select wells candidates for water control treatment.
Tubing Stress Analysis to Design Completions for Mangala Oil Wells—Onshore India
Authors: Kumar Vipin , Singh Ratan , Mabunga Shodji J. 
Published: January 2010

Abstract
The Mangala oil field contains 27-30°API waxy, low GOR crude oil, with a wax appearance temperature within 5°C of reservoir temperature (60-63oC) and a pour point above 40°C. To meet the flow assurance challenges for such paraffinic crude, jet pumping with hot water at 85°C as power fluid is the first choice for an artificial lift system. Power fluid surface injection pressure is designed to be 3,000 psi. Wells are expected to produce up to10,000 barrels per day of oil or oil and water.
High temperature, high pressure power fluid in the annulus means that the completion string will be exposed to high external pressures and variations in the casing/tubing temperature profile during the life of the well. High compressive forces, the potential for collapse, wellhead growth and the extreme case of anticipated helical buckling make the well completion design quite challenging. It is important that the well completion design is capable of withstanding such conditions. The accurate representation and prediction of casing/tubing temperature, pressure profiles and loads in the casing/tubing during all well operations including jet pumping are crucial to assess the integrity of the completion string.
This paper describes the anticipated loads during the well life, and use of a wellbore thermal simulator, and tubular stress analysis software program to simulate the potential stress loads. This helped optimise the design of the casing and tubing strings to anticipate and foresee and avoid potential problems like connection leaks, permanent tubing buckling, packer load requirements, etc.
Steam-Solvent Coupling at the Chamber Edge in an In Situ Bitumen Recovery Process
Authors: Sharma Jyotsna , Gates Ian D. 
Published: January 2010

Abstract
Alberta, Canada contains about 170 Gbbl of recoverable heavy oil and bitumen; most of it with in situ viscosities in the hundreds of thousands to millions of cP. To mobilize and produce this oil, steam-based recovery methods such as Cyclic Steam Stimulation and Steam-Assisted Gravity Drainage are used. Given the large energy requirements and volumes of emitted greenhouse gas from these processes, there is strong motivation to develop enhanced recovery processes with lower energy and emission intensities. One incremental move to achieve this is by using steam-solvent hybrid processes such as ES-SAGD where solvent is co-injected with steam. Steam- solvent processes are the next generation of reduced emission to atmosphere recovery processes for heavy oil and bitumen reservoirs beyond current steam recovery methods. The controlling feature of these processes is the mobilization and drainage of oil at the depletion chamber edge. Furthermore, both oil phase viscosity – mobility and density – drainage – depend strongly on temperature and solvent concentration. Here, a simple model is derived to describe dynamics of thermo-solvent coupling effects in the mobile oil zone at the edge of a steam-solvent chamber. A double front system evolves: compositional and thermal fronts result with different length scales. They are coupled through velocity and viscosity fields. We investigate the extent to which these fronts affect oil mobility at the edge of the chamber. The solvent provides an additional means to raise oil phase mobility beyond that achieved with heat. The enhanced mobility is due to 1. lowered viscosity because of solvent dilution and 2. slightly raised oil saturation due to addition of solvent (raises the oil effective permeability). Due to synergistic interactions between heat transfer and solvent diffusion, the oil zone has higher mobility in the solvent-steam system over that of the steam-only one. Therefore, steam-solvent systems lead to lower energy and emission intensity thus "greening", to some extent, heavy oil and bitumen recovery technologies.
A Huge Oil Spill Naturally under Control in Abadan Refinery
Authors: Zoveidavianpoor Mansoor , Shadizadeh Seyed Reza 
Published: January 2010

Abstract
A rapidly expanding chemical and petroleum industry has been responsible for great improvements in the quality of urban areas in Iran over the last 100 years. The Abadan Refinery is located between the Arvandrud and Bahmanshir rivers in the highly populated Abadan city. These rivers supplies urban, industrial, and agricultural waters to Abadan city. During the war between Iran and Iraq, leakage of enormous volumes of oil and refined petroleum products from storage tanks and pipelines at the Abadan refinery to the surrounding environment occurred. Underground contamination resulted from that leakage is a serious and a growing enviromental concern in Abadan city. In this work, twenty boreholes were investigated by considering petroleum leakage to the surrounding area during and after the war. Geological conditions, stratigraphy and petroleum contamination underlying the Abadan refinery was determined from cores during the drilling of the boreholes.
Oil saturation of cores was defined for each borehole. Also, porosity, and density of the cores were measured in this project. The extent of the petroleum contaminated underground layers was determined in this study and the average depth of contaminated undrground layers is from the surface to the depth of 4.5 meter. Leakaged oil in place in underground layers of Abadan refinery was estimated to be 6,424,674 barrels. The results show that the majority of existing petroleum in underground layers at Abadan refinery was absorbed by clay.
Construction and Implementation of Integrated Production Network Model in A Complex Onshore Operation
Authors: Aditama P. , Sujai A. , Pamungkas H. W. , Firmansyah V. , Rohman A. F. 
Published: January 2010

Abstract
The development of oil and gas fields in recent years has become more technically and economically challenging. Interdisciplinary interaction is needed to have effective and efficient field planning. Indeed, it has been noted that field management by using integrated surface-subsurface modeling will have an extremely positive effect on production.
This paper presents the interdisciplinary teamwork between subsurface and surface engineering in their efforts to construct an integrated production model for Kaji Semoga field, a large and complex onshore production field located in South Sumatra, Indonesia. The model covers about 180 wells, which are spread over 45 clusters, and surface facilities in three field processing stations. It covers all facilities from well up to the nearest field station for separating gas from oil and for compressing it prior to distributing to clusters and finally injecting the well. The model also incorporates 84 new ESP, which will be installed by the end of year 2009 to replace the existing gas lift system.
The model predicts an additional oil gain of 2,500 bopd (14.7%) as a result of installing ESP. About 170,000 blpd of liquid will be produced after the ESP installation project is completed. Consequently, liquid handling in each station has become a critical issue to be resolved before all the ESPs are installed. Several operational manoeuvers have been carried out to handle the forthcoming produced liquid by utilizing the model. About 300 bopd (1.8%) of oil gain from the cluster flow diversion scenario has already been realized.
Apart from the liquid handling issue, the model also highlights the future gas-lift gas requirement for the remaining gas lift wells. Several active compressors can be shut down as a result of the outcome of the model, so the operating cost can be reduced significantly. The model also identifies potential bottlenecks along the production trunkline, which can result in a potential reduction of 140 bopd. In addition, the model also identifies a potential oil gain of about 220 bopd (1.3%) if back pressure on several production trunklines can be minimized.
Field engineers have benefitted from the use of this model: it can help them assess any changes or manoeuvres in the field. This is expected to add about 200 bopd (1.2%). Some of these changes and manoeuvres are being executed this year.
Reservoir Management of Brown Field: Kalol, A Case Study
Authors: Vij R. K. , Das Minoti , Kumar Sudhansu 
Published: January 2010

Abstract
Kalol is a multi-layered field comprising of nine pay zones. Pay zones II, III and IV are both oil and gas bearing while pay zones V, VI + VII, IX + X, XI and XII are oil reservoirs. The field has in-place (PD) reserves of 131.84 MMt of oil with an ultimate (PDD) component of 18.23 MMt as on 1.4.2009 respectively. The cumulative production as on 1.4.2008 is 12.77 MMt of oil leading to a recovery of 9.7%.As on 1.4.2008 a total of 610 wells are drilled of which 385 wells are completed as oil wells with 329 flowing & 56 non-flowing wells, 23 as flowing gas wells and 80 as water injection wells. Out of total flowing oil wells 91 % are operating on artificial lift with 140 wells on SRP and 159 wells on gas lift. The average rate of production during the year was 1140 tpd of oil and 259000m3/d of gas. The oil production was maintained mainly by development drilling, zone transfers, lift management and faster revival of ceased wells. Water injection is being carried out in pay zones K-III, V, VI+VII, IX+X and XII through 68 wells @2600 m3/d. Due emphasis was given for pressure maintenance schemes to meet instantaneous void age compensation through proper redistribution and focused water injection.
Induction of various technologies are been attempted to maintain the oil production rate from this Brown field, major among them are drilling of Horizontal, Multi-lateral and high angle wells, MEOR technologies, application of PDB technology, Hydro-fracturing, Stimulations of tight sand stone-layer, enhancing the quantity and quality of water injection for effective pressure maintenance and improving the recovery factor.
Various surface and sub-surface interventions through multi-disciplinary team approach have paid rich dividend and production of the field have enhanced through these initiatives. Paper will discuss the innovative approaches conceptualize and implemented in the field for maintaining and enhancing the production level and improving the reservoir health.
Investigation of Gas Well Liquid Loading With a Transient Multiphase Flow Model
Authors: Yusuf Rahel , Veeken Kees , Hu Bin 
Published: January 2010

Abstract
Liquid loading in gas wells occurs when the gas flow rate falls below a critical value due to reservoir depletion where the accompanying liquids can not be lifted up to surface. Since liquid loading has a detrimental impact on production, deliquification methods need to be employed in order to recover the production. To choose the right deliquification measures and achieve a timely deployment, it is therefore important to predict the onset of liquid loading in advance. Traditionally, the Turner correlation has been used for this purpose. However, latest published data from deviated large diameter offshore wells show that the Turner correlation can underpredict the critical gas rate by 20-200%. The operators can be misled by this prediction and are often not well prepared for tackling the liquid loading as they may think the problem is still some years away.
Liquid loading is a transient phenomenon in nature and thus needs to be described by a dynamic multiphase flow model. In the present study, instead of modifying or improving the Turner correlation, a comprehensive dynamic multiphase flow model is used to predict the onset of liquid loading. Totally fourteen offshore gas wells were simulated using the dynamic model. The predicted critical gas flow rates are validated against field data and the predictions lie within the ±20 % error margin. The effect of condensate gas ratio (CGR) on liquid loading is also investigated. The simulations show that it is possible for low CGR wells that the critical gas flow rate can decrease with the increasing CGR. This is also in line with the field observations.
This study brings forth the importance of transient multiphase flow modeling and opens new frontiers for dynamic simulation of gas well deliquification, which shall set up guidelines from dynamic point of view for implementing the right deliquification measures so that more production can be recovered when loading has happened.
Hydraulic Fracture Propagation in a Naturally Fractured Reservoir
Authors: Chuprakov D. A. , Akulich A. V. , Siebrits E. , Thiercelin M. 
Published: January 2010

Abstract
We present the results of numerical modeling that quantify the physical mechanisms of mechanical activation of a natural fault due to contact with a hydraulic fracture. The analysis of the total stress state along the fault during the hydraulic fracture coalescence stage makes it possible to define a criterion for reinitiation of a secondary tensile crack at the fault. Numerical simulations of the fracture interaction for a wide range of key parameters have been performed to detect the possible fracturing scenarios.
A Derivation of Drilling Fluid Modeling for Pr # 2 Well (Kg Basin - India) in Terms of Geo-pressure Gradient and Geo-mechanical Stress for Extra Wellbore Stability of Its over Pressured Highly Reactive - Water Sensitive Shale Column of 1225 Mtrs in 8-½ Inch Borehole from 2883 Mtrs to 4108 Mtrs Tvd: A Critical Analysis of Shear Failure Pressure and Chemical Osmosis during Fluid - Shale Interactions
Authors: Giri Jagdish P. 
Published: January 2010

Abstract
Success of achieving extra well-bore stability in highly reactive shale column of 1225 mtrs, in PR#2, is attributed to adequate pre-well planning, execution of drilling plan and guidelines, and the K+Cl -Polymer Drilling fluid chemistry. Well-bore cleaning and hydraulic modeling in an integrated geo-pressure gradient and critical analysis of shear failure pressure due to chemical osmosis and fluid - shale interaction was the significant attribute on well-bore stability. Pre well modeling of well-bore stability in problematic shale - zones and hole cleaning in its deeper final phase, contributed to stable hole behavior during unexpectedly longer durations on non - drilling downtime for frequent surface equipment failures, etc. Paper critically analyzes shear failure pressure and chemical osmosis during fluid - shale interaction to improve better well construction - design and drilling fluid modeling for productive oil - field economics in entire KG Basin - India. Key conclusions drawn from such a critical analysis of water based K+Cl - K+ Lignite/PHPA Polymer mud system include: Hole cleaning and hydraulic model derived in this analysis, proved to be quite useful in the pre well planning process as well as in post - well analysis on high bore-hole stability.Chemical osmosis and shale - fluid interaction further demonstrated the pore pressure transmission, and geo-pressure variance, and its integration with geo-mechanical stress and shear failure pressure derived the well-bore stability modeling.
The case study presented compares original mechanical stability and hydraulic- fracturing estimates with the critical mud weight identified for successfully completing this difficult operation. Descriptions of well-bore stability and fluid losses are presented along with drilling fluid parameters used to combat them. Method used for estimating formation pore pressure, in-situ stresses and formation rock properties are also described. Additionally, possible explanations for differences between planned and actual stability estimates are explored with future recommendations for similar operations.
Experimental Investigation of Biopolymer and Surfactant Based Fluid Blends as Reservoir Drill-in Fluids
Authors: Ogugbue Chinenye C. , Rathan Mayur , Shah Subhash N. 
Published: January 2010

Abstract
Biopolymers present non-toxic and degradable fluids that have been used extensively in reservoir drill-in fluids (RDF) to drill through reservoir rocks in oil and gas wells. Their numerous advantages, such as viscosity enhancement, filtration control, flocculation prevention, friction pressure reduction during turbulent flow conditions and shale stabilization amongst others have made them indispensable in oilfield applications. At the same time, the inherent formation damage as a result of the polymer molecules settling or being adsorbed on or into the reservoir rock pore spaces has been an area of concern to the industry. On the other hand, surfactant based fluid (SBF) systems typically leave little residue or formation damage compared to biopolymer systems, thereby gaining acceptance as RDF’s. Low interfacial tension existing between SBF’s and the produced or injected fluids is one of the major criteria for this reduction in formation damage. However, SBF has much higher fluid leak-off at reservoir conditions than wall-building biopolymer fluids, which has significantly limited their use in the industry.
In this paper, several blends of a SBF or visco-elastic surfactant (VES) and a water soluble biopolymer, welan gum have been used to develop a SBF-biopolymer fluid system based upon compatibility, rheological and visco-elastic behavior. The study was performed by characterizing biopolymer-VES fluid systems for their ability to retain their rheological and visco-elastic properties at elevated temperatures. Data analysis showed that the blend captures the merits of the individual fluid systems, as well as reduction in overall cost as compared to using a SBF mud by itself. Blends consisting of higher concentrations of welan gum showed good thermal stability and retention of viscosity at elevated temperature. Hence, cost reduction is achieved in the amount of SBF utilized. Also, the results of surface tension measurements showed that the binary system exhibited values much lower than welan gum fluid, and about the same as the SBF. Filter press tests results showed the blends to have a lesser fluid loss. Other potential applications of this binary system are also discussed.