bluuebunny/crossref_metadata_2025 huggingface dataset:
Gas Lift with Nitrogen Injection Generated in Situ
Authors: Aguilar Miguel A. Lozada , Monarrez M.del Remedios Arredondo
Published: December 2007

Gas lift is a feasible option as an artificial lift system in a depleted field. In the Bellota field there is no substructure means to install any type of artificial lift system, therefore the use of nitrogen as a gas lift source is necessary to keep the Bellota wells producing. After evaluating different options we implemented a nitrogen generated in situ project using the membrane technology.

This paper analyzed the gas lift process design by using nodal analysis and optimum allocation of nitrogen in each well. Special emphasis and consideration was given to this project from an economical, operational, technical and environmental points of view. It is olso compares this option with differents alternatives including the traditional gas lift method using natural gas as a source as well as the use of stored nitrogen from storage trucks (Tanks). Our evaluation of results obtained from the different options investigated in this study clearly indicates that this method is a good option in this particular situation.

Nitrogen injection generated in situ with membrane technology can be a feasible and profitable alternate source of gas lift as shown in this study.
Realistic Numerical Models for Fractured Reservoirs
Authors: Gurpinar O. , Kossack C. A.
Published: December 2007

Characterization and forecasting in fractured reservoirs is one of the most challenging topics in the oil and gas industry. Managing such reservoirs requires construction of representative reservoir models that can handle both fracture and matrix systems, and their interaction, correctly. Data integration from all disciplines is required for construction of these reservoir models.

Commercial numerical models capable of handling flow in fractured reservoirs have been present in the industry for quite some time. However the correct application of those simulators for representative reservoir models is not easy. This paper will discuss parametric ways to improve construction of representative reservoir models. Discussion will focus on transition from single porosity representation to dual porosity models and pseudoization process employed in between.

A fractured reservoir undergoing a waterflood is simulated with a single porosity formulation, where the matrix blocks are sub-divided into core plug size grid blocks and the fractures are sub-divided into even smaller blocks. The results from this fine grid are considered the "solution" to the displacement in the fractured reservoir. The grid is coarsened and the effects of scale-up are observed. Pseudos are developed for a coarse grid so that the results match the "solution". The reservoir is then simulated with a Dual Porosity simulator. The sensitivity of the dual porosity results to the refinement of the numerical grid is studied.

A comparison is made between the "solution" and the Dual Porosity simulator results. Several of the advanced features found in commercial Dual Porosity models are tested to see how well they improve the comparison. A scale-up pseudoization is determined that allows the Dual Porosity simulation to match the "solution". A larger sector model is then simulated with the pseudo capillary pressure to investigate the robustness of the scale-up pseudoization. Recommendations are provided that describe a procedure for using the Dual Porosity Model to simulate displacements in a fractured reservoir in a more accurate way.
Characterization and Synthesis of Synthetic Drilling Fluid Shale Stabilizer
Authors: Avilés-Alcántara Cristina , Carlos Gúzman C. , Aarón Rodríguez M.
Published: December 2007

Abstract(1–4)

Environmental constrains on disposals of cutting and drilling fluids have precluded the use of oil base mud (OBM), in addition drilling with OBM can introduce a contaminant into the reservoir. Alternative or synthetic fluids have been developed with many of beneficial properties of inverted emulsion which offer advantages beyond the fact that they are environmentally accepted. In this experimental research emphasis is given to the results of the efficiency of a new water base system, which include the use of a new shale stabilizer additive.

Anionic polymers were studied and synthesized of type anionic (ionizable groups with negative charge. It is described the synthesis of homopolymers of acrylic acid (PAA) with differen conditions of synthesis, homopolymers of AA and Dialildimetilammoniumchloride (DADMAC).

The characterization phase involves the molecular weights and viscosities determination for homopolymers AA and molecular weights by an alternate method for copolymers of AA-DADMAC, use of I.R. spectroscopy for the structure elucidation.

To prove the efficiency of the system were developed CIC test, swelling and dispersion test (by using cores from the Gulf of Mexico basin), rheology HPHT, filtration tests, TSC, lubricity.

The results of the describe experiments involved in the hydration of shale. Experimental details and results will be presented.
Use of Drilling Parameters for Planning Effective Payzone Isolation
Authors: Rodríguez W. , Garcia M. , Pestana D.
Published: December 2007

The present job is a methodology to systematize the cementing job operation based on drilling information in order to define slurries, preflushes and procedure for planning, execution, controlling and evaluation of cementing job.

Difficult geometry, high deviated angle, shallow and deep gas wells, gelled mud and oil based mud are some of the harsh environments where this methodology has been used successfully.

Results show excellent zone isolation of Payzone and their impact on drilling.
Environmental Management, Cost Management, and Asset Management for High-Volume Oil Field Waste Injection Projects
Authors: Bruno Michael , Reed Alex , Olmstead Susanne
Published: December 2007

Ongoing exploration and production activity, combined with increased regulatory requirements, are increasing the volume and costs associated with disposal of oil field wastes, including produced oily sands and tank bottoms, drilling mud and cuttings, crude contaminated surface soils, and naturally occurring radioactive materials (NORM). A cost-effective and environmentally sound disposal option is to re-inject waste material into the subsurface into non-productive and/or depleted zones under controlled fracture conditions.

High volume injection projects often involve annual injection exceeding several hundred thousand barrels of waste for several years. The critical engineering management goals for such operations are to:

Maintain waste containment in the target formation (environmental management); Sustain long-term injectivity with minimum equipment repairs and well workovers (cost management); and Maximize formation storage capacity and well life (asset management).

More than five years experience operating, analyzing, and managing large volume waste injection projects in the US and Canada has enabled Terralog to develop specific design, monitoring, and operating strategies to achieve these goals. Target injection formations must be selected with appropriate overlying barrier and absorption zones. Offset well completions must be carefully examined. The injection well completion should be appropriately designed to take into account high formation stresses and potential movement. Continuous monitoring and analysis must be performed to evaluate varying formation properties, injectivity, stress conditions, and fracture orientation and height growth. Finally, through continuous monitoring and analysis of formation response, injection parameters and properties (such as solids concentration, density, flow rate, shut-in time, etc…) can be adjusted in order to maintain containment, reduce operating costs, and optimize long-term injectivity.
Successful Application of a Novel Fracturing Fluid in the Burgos Basin, Mexico
Authors: Centurion Sergio , Alcantar Manuel Silva , Rascon Austreberto Rios , Ortega Aaron Torres
Published: December 2007

The only way to obtain an optimum production in the wells that form the Burgos basin in the north of Mexico is using the hydraulic fracturing technique.

This paper describes how was the evolution of fracture fluid since 1996 till now, based mainly on each stimulated zone's depth and temperature.

A new frac fluid, whose main characteristic is the low polymer load used to stimulate moderate to high temperature wells, was introduced within a process of optimization performed by Petroleos Mexicanos.

The detailed information here can be useful for future hydraulic fracture treatments to be performed in this zone.

On the other hand, a typical case was analyzed using a fracture simulator linked to a production simulator. A comparison of the production result using two fluids (a conventional one and a low polymer load new one) was made.

The advantage of the production company when using this new technology in fracture fluid was determined.
Three-Phase Immiscible WAG Injection: Micromodel Experiments and Network Models
Authors: Larsen J. K. , Bech N. , Winter A.
Published: December 2007

This paper is concerned with planning and optimization of three-phase immiscible Water-Alternating-Gas (WAG) injection processes. This goal is achieved by applying an iterative procedure linking the pore-level displacement mechanisms with a macroscopically defined WAG process.
Alkali / Surfactant / Polymer at VLA 6/9/21 Field in Maracaibo Lake: Experimental Results and Pilot Project Design
Authors: Manrique E. , De Carvajal G. , Anselmi L. , Romero C. , Chacón L.
Published: December 2007

The VLA 6/9/21 Field is a waterflooded light crude oil reservoir located in Maracaibo Lake, West Venezuela. In the last two years PDVSA E & P has developed Integrated Laboratory Fields (ILF) as a strategy to evaluate new technologies and EOR methods in order to improve light and medium oil recovery factors. Alkali/Surfactant/Polymer (ASP) is one of the chemical flooding technologies that has recently been evaluated in Venezuela.

The objetive of this study is to describe the followed methodology to develop ASP formulas, describe the pilot test planned for this year and also to determine whether ASP technology can produce incremental oil in the Eocene C-4 Unit of VLA 6/9/21 Field economically. The study was performed at reservoir temperature of 90°C with dead crude oil and rock sandstones from the oil producing zone located in the pilot area.

Several ASP formulas were developed for the VLA 6/9/21 Field with comercial petroleum sulfonates. Each ASP solution gave interfacial tension (IFT) values below 9x10−3 dynes/cm. Rheologic studies with polyacrylamide polymers using different additives indicate that the solution viscosity can be mantained over the time at least 2 cp above the crude oil viscosity (2,5 cP) at reservoir temperature. Surfactants, alkali and polymer retention were below 0,08 mg/g rock. Incremental oil recoveries were higher than waterflood, obtaining recoveries between 22 and 39% OOIP for 0,3 PV ASP and 0,15 PV polymer injection in reservoir cores. The positive results of this laboratory study provided an ASP formula for a pilot test supported with the injection of oil partitioning tracers before and after the chemical additives as part of one of the ILF of PDVSA E & P.
Reservoir Characterization and Laboratory Studies Assessing Improve Oil Recovery Methods for the Teague-Blinebry Field
Authors: Svec Robert K. , Grigg Reid B.
Published: December 2007

A study to review previous work, perform additional laboratory tests, and identify pay from well logs in the Teague-Blinebry field was performed at the New Mexico Petroleum Recovery Research Center (PRRC) a division of New Mexico Institute of Mining and Technology. Recovered core from one well and well logs from across the field were evaluated. Laboratory results included:

Mineralogy, fracture systems, and oil stains were described for 251 ft of recovered core. Slabbed core scanning minipermeametry were performed on 79 samples, air permeabilities on both ends of twelve plugs, brine permeabilities on two samples, and water and carbon dioxide (CO2) floods on two samples. Minimum miscibility pressure was determined to be the higher of 1010 psig or the system bubble point pressure. Wettability index was determined to be ‒0.608.

Core permeability measurements identified very low matrix permeability in the Blinebry dolomite. Regions of conductive vugs and fractures were detected. Tests indicate that even apparently filled fractures play a significant role in fluid movement. This observation is supported by effective permeability results, derived from step rate tests, of 1.15 md; well above the average matrix permeability.

Density/neutron and induction or laterologs were used to identify pay in 16 wells with modern log suites. In order to include a greater number of wells, a procedure was adopted in which field average parameters were used with 47 sonic porosity logs from the older wells lacking density/neutron data. Net pay and original oil in place were calculated for 63 wells. Targets for potential water or CO2 flood development are identified as the upper one-third of the Blinebry.
Historical Use of m and a in Well Log Interpretation: Is Conventional Wisdom Backwards?
Authors: Adisoemarta P. S. , Anderson G. A. , Frailey S. M. , Asquith G. B.
Published: December 2007

Archie's laboratory experiments established a relationship between the formation resistivity factor and porosity, which set forth the use of two constants: m and a. From Archie's work these constants were regression constants representing the slope and intercept, respectively. Subsequent researchers used the general form of Archie's relation, but they found differing values for m and a. The terms cementation factor and tortuosity factor have been used to describe each of these terms. Conventional wisdom believes that a higher m relates to vuggy porosity and a lower m suggests fracture porosity. This is generally true if the tortuosity factor is assumed (typically 0.81 or 1.0) and the cementation factor is calculated.

However, if m and a are found simultaneously, theory and many laboratory observations suggest the opposite may be more likely. This study shows that the tortuosity factor, a, is a function of the average angle of electrical movement with respect to the bulk fluid flow, and cementation factor m is related to the flow area contrast between pore throat and pore body.
Diagnostic Techniques to Understand Hydraulic Fracturing: What? Why? and How?
Authors: Cipolla C. L. , Wright C. A.
Published: December 2007

In recent years there have been numerous advances in fracture mapping/diagnostic technologies. This paper details the state-of-the-art in applying both conventional and advanced technologies to better understand hydraulic fracturing and improve treatment designs. The initial portion of the paper describes the application and limitations of various diagnostic tools and methods, including well testing, net pressure analysis (fracture modeling), techniques that employ open-hole & cased-hole logs, surface & downhole tilt fracture mapping, microseismic fracture mapping, and production data analysis. The bulk of the paper is dedicated to case histories that illustrate the application of these various fracture diagnostic technologies. The case histories include examples of how several fracture diagnostics can be used in concert to provide more reliable estimates of fracture dimensions and allow better economic decisions.
Production Optimization of Gas Wells by Automated Unloading: Case Histories
Authors: Foo David B.
Published: December 2007

This paper documents attempts to automatically unload gas wells in the Western Sedimentary Basin at various depths and producing conditions. The results include production increases of 25%, with reduced operating costs. The criteria for application of this technology and a cost/benefit analysis are presented. This work is being incorporated in a large-scale project currently underway in Oklahoma, which will be discussed briefly as an example of integrating automation technology with expert systems to provide field-wide optimization of a major gas field.
Experimental Investigation on the Rheology of Foams
Authors: Bonilla Luis Fernando , Shah Subhash N.
Published: December 2007

In this study, the rheology of foams was investigated using aqueous foams and gelled foams and employing a pipe type viscometer. Water was used as the liquid phase for the aqueous foams while guar was used as the gelling agent for the gelled foams. Surfactant at 0.5% (vol.) concentration was used as the foaming agent. The flow data showed that foams behave like Herschel-Bulkley model fluids.

New empirical correlations have been developed from the experimental data to predict foam fluid apparent viscosity. These correlations are function of liquid phase properties and foam quality and are applicable to the foam systems tested in the wide range of shear rates and temperatures investigated. The use of these new correlations will provide more accurate estimation of the foam fluid rheological properties.
Development of Gas-Condensate Reservoirs by Directional Intracontour Waterflooding
Authors: Berman L. , Ryzhik V. , Mirotchnik K. , Allsopp K.
Published: December 2007

This paper presents an overview of some of the advanced water-flooding technologies developed for gas-condensate reservoirs (GCR) in the former Soviet Union. Although developed in the 1970's and since then successfully applied in the field, there are no published accounts of this technology being applied elsewhere.

This technology is based on both the block structure of most gas-condensate reservoirs and the " block reservoir structure" of major fields. In both case areas of low permeability connect seemingly separate reservoirs or field zones. These areas of low permeability act in a manner similar to semi-permeable membranes. The flow of water through low permeability areas, especially those containing clay deposits, takes place only if the pressure gradient exceeds some initial value (initial gradient). Such phenomenon also occurs for gas flow, but the values of the initial pressure gradient for gas (Gg) are much lower than for water. As a result, injected water cannot flow through these areas of low permeability and move from one highly-permeable zone to another. However, at the same time gas can flow freely from block to block provided the pressure gradient is higher than Ggi. The properties of gas-saturated rocks prevent water invasion into the "dry" blocks, until the blocks with injection wells are almost totally saturated by water (at Sgres). By utilizing this phenomena, greater gas and condensate recoveries can be achieved than by using water injection schemes which disregard the intrinsic heterogeneity of reservoirs.

An experimental laboratory program verifying the phenomenon of initial pressure gradient was performed in the TIPM Laboratory in 1999. This work is ongoing.
Automation System Case Study of Coalbed-Methane Development
Authors: Robertson Steve K. , Pool Mike , Farrens Michael J. , Butts Tammie J.
Published: December 2007

Can an independent producer fulfill a vision to develop and produce a coalbed methane gas field that covers two hundred square miles in a remote desert plateau in the western United States? This paper will answer that question as well as provide answers to other pertinent questions, such as, "What tools would be available to the operator to efficiently and safely produce the wells?" And, "Would the tools allow for future expansion and/or allow new technologies to be incorporated into the system cost-effectively?"

This case study will show how River Gas Corporation was able to successfully meet their needs with an automation system that was jointly developed with an engineering/ manufacturing company. All phases of the project, from its inception in 1991 with a 13-well pilot project to a planned 600-well development will be discussed. Innovative solutions successfully answered the above questions and allowed the system to evolve to meet the continuing changes in expansion and production needs.
Evaluation of Acid Treatments in Horizontal Wells
Authors: Zhu D. , Hill A. D. , Looney M. D.
Published: December 2007

Acidizing is often applied in horizontal wells to improve well performance. Acidizing in horizontal wells differs significantly from the acidizing of vertical wells. The length of acid contact is much longer, the formation properties over the contact length likely vary in a larger range, and the cost is generally higher. To enhance the effectiveness of matrix stimulation, methods to evaluate and optimize acid treatments similar to those used for vertical wells can be adopted for horizontal wells.

This paper introduces a simple approach to evaluate horizontal well response to acid treatments. Skin factor was calculated explicitly in the method from pressure and flow rate, which can be directly measured during a treatment. Skin factor is then used to identify the well response to acid injection, and therefore to understand and control the stimulation process. There have been several mathematical models published to simulate the pressure/flow rate behavior of horizontal wells. Most of them have complicated solutions and have to be solved numerically. We selected and modified analytical solutions for horizontal well performance that can be implemented for field evaluation of acid treatments.

Field examples presented in the paper show how to apply the evaluation method for horizontal wells. The method can assess the effectiveness of acid treatments and can be used to optimize subsequent treatments.
Encapsulated Scale Inhibitor Treatments experience in the Ghawar Field, Saudi Arabia
Authors: Hsu J. F. , Al-Zain A. K. , Raju K. U. , Henderson A. P.
Published: December 2007

An alternative scale inhibition method using encapsulated scale inhibitor has been successfully used to control calcium carbonate scaling in the Ghawar Field oil wells of Saudi Aramco, Saudi Arabia. Field tests indicate that the Ghawar Field requires a low threshold scale inhibitor concentration for scale mitigation. The encapsulated phosphonate scale inhibitor treatment procedure is thus ideally suitable for scale control in such fields. Since 1994, a total of 89 wells have been treated with this procedure. After more than five years of treatment, there has been no reappearance of scale deposit on the treated wells except for two instances of scaling. Low treatment cost and the resulting long treatment life have provided an excellent incentive to treat more wet producers using the encapsulated scale inhibitor treatment method instead of treatment by conventional scale inhibitor squeezes. An additional benefit is realized from this encapsulated inhibitor method when treating marginal high water cut wells and wells located in low pressure areas by ensuring that the wells sustain flow after the treatments without the need for extensive livening work.

This paper presents the results of a field case study where calcium carbonate scaling was controlled using the encapsulated scale inhibitor treatment procedure. Treatment design, job procedure, inhibitor return monitoring, economic analysis and comparison with conventional squeeze treatments as well as future applications are presented.
Health-The Forgotten Element: The Workers Perspective
Authors: Stephenson C. D. , Molloy J. K.
Published: December 2007

HSE, Health, Safety and the Environment. These three elements dominate virtually everything we do in offshore operations around the UK, and indeed around the world. But do they? ‘Safety is Priority’. At local, national and international levels, there are new initiatives being rolled out on a regular basis aimed at reducing incident and accident rates. Acknowledgement of issues such as global warming, and a greater awareness of our fauna and flora across the globe, has heightened awareness on the environmental front. But what of health? We believe that health issues are lost in the drive to address safety statistics. Not physical health, there are countless initiatives on healthy eating, exercise etc. No, mental health. The stress factors faced by an ever increasing number of workers across the industry is, in our opinion, impacting on the other elements of Safety and the Environment.

In recent years the UK sector has seen a sharp increase in the number of fatalities, major injuries and incidents. Why? Industry tells us that the greater percentages are attributable to human error.i The same is said when incidents are of an environmental nature. But why are we having so many human failures? Highly skilled, highly motivated, intelligent workers making so many mistakes? Victimisation, discrimination, harassment, disillusionment, depression, all have a psychological effect on workers. All are present in the UK industry today. All of them breed an attitude, a mindset, a ‘culture’ amongst workers. We hear so much about creating a ‘safety culture’, yet fail to see the problem.

The only objective measure of ‘culture’ is in studying what people do as opposed to what they say. What the industry is currently saying differs greatly from what they are actually doing, and we will demonstrate this through practical example.
Fitness to Work: Computer Assisted Health & Fitness Assessment
Authors: Keech J. , Steele C.
Published: December 2007

A computer assisted health and fitness assessment process has been used for five years in a major North Sea operator. The system is used to establish fitness to work especially offshore. The process has raised the profile of health, engaged the workforce in health improvement. It is cost effective and empowering for the health staff. The data generated is a major source of information about an offshore workforce.
A Step Change in Safety
Authors: Williams S. , Carroll D. , Thomson A. , Watkins G.
Published: December 2007

This paper outlines the setting-up and progress of a cross-industry initiative to bring about a step change in safety.

The ‘Step Change in Safety’ initiative was launched in 1997. It was based on a commitment by leaders from UKOOA, IADC and OCA to deliver a 50% improvement in safety performance over three years.

A strategy was embarked on to:

demonstrate the commitment of the industry leaders develop greater cross-industry co-operation for sharing and learning good practice engage and involve all people employed in the industry in the improvement process.

This paper details the stages of development of the ‘Step Change in Safety’ initiative, the achievements that have been made and the challenges for the future. In particular, it introduces the Safety Culture Maturity Model and Safety Culture Improvement Process developed by a behavioural issues task group.

Details of the work of some of the Step Change task groups are described in other papers presented at this conference1,2,3,4,5.
Grooming Responsible Adolescents in the Times of AIDS (RATA): A Comprehensive Health Promotion Workshop for Young-Dependants of Oil and Gas Workers in Nigeria
Authors: Faleyimu B. L. , Fagade O. A. , Imala I. H. , Ubuane L. A. , Kpiasi E. O.
Published: December 2007

Recent reports indicate that there is increasing rate of sexual intercourse amongst Nigerian Adolescents. They are poorly informed about reproductive health and their main sources of information on such intimate subjects are peer groups, or schoolmates with the media contributing moderately and Parents playing the least role. This scenario is expected to be worse with Field-Based Oil Workers who are highly mobile, spending long time away from home, have poor access to health information and hence impact no sexuality education on their young dependants.

Using Key Informant Interviews and Focus Group Discussions (FGD), 200 dependants of Oil & Gas Employees of Chevron Nigeria Limited (CNL) between 14 -24yrs of age in Warri Nigeria, were studied to assess their social and reproductive health perceptions. The Medical Unit of CNL organized a youth-friendly comprehensive reproductive-health promotion workshop for these randomly selected youths nominated by their parents with the theme-"Responsible Adolescents in the Times of AIDS" [RATA]. This Enter-education consists of lectures (on HIV/AIDS, Drug Abuse, etc), Film Shows, Quiz, Dance drama, etc. with the youths participating. Souvenirs were also distributed to sustain knowledge gained and promote Peer education.

The study revealed poorly informed youths with poor risk perception and high rate of Sexually transmitted diseases (STDs). The post workshop FGD revealed more informed youths that were ready to take decisions that will protect them from health hazards, practice safe sex and become role models to other youths in their community.

Though RATA is a pilot project, the benefits of the workshop cannot be overemphasized. The participatory approach by the youths enhanced their positive response to the consequences of STDs, unwanted pregnancies, drug abuse and violence. In the near future, a modified form of this program will be extended to parents, guardian and teachers in this community to enhance its success.
Health Program Planning: Analysis and Overview of World Bank Guidelines and Requirements
Authors: Krieger G. R. , Balge M. Z.
Published: December 2007

In 1995-96, the World Bank issued new guidelines covering the nature and content of health services for large infrastructure projects in sub-Saharan Africa (SSA). These guidelines proposed a substantial paradigm shift from the more traditional tropical disease prevention approach. Under the World Bank approach, a sectoral, e.g. housing, sanitation, transportation communications, urban development, strategy for disease prevention and management is advocated. A useful approach is to adapt the Bank's new paradigm but still retain many of the proven benefits of a disease specific approach for problems like certain infectious diseases like malaria, AIDS, TB and hepatitis. Health matrices and disease specific planning maps are useful tools that will be presented and discussed.
Electromagnetic Heating Methods for Heavy Oil Reservoirs
Authors: Sahni Akshay , Kumar Mridul , Knapp Richard B.
Published: December 2007

The most widely used method of thermal oil recovery is by injecting steam into the reservoir. A well-designed steam injection project is very efficient in recovering oil, however its applicability is limited in many situations. Simulation studies and field experience has shown that low injectivity reservoirs and small thickness of the oil-bearing zone limit the performance of steam injection. This paper discusses alternative methods of transferring heat to heavy oil reservoirs, based on electromagnetic energy. We present a detailed analysis of low frequency electric resistive (ohmic) heating and higher frequency electromagnetic heating (microwave frequency).

We show the applicability of electromagnetic heating in two example reservoirs. The first reservoir has thin sand zones separated by impermeable shale layers and viscous oil (9541 cp at initial reservoir conditions). We model preheating the reservoir with low frequency current using two horizontal electrodes, before injecting steam. The second reservoir has low permeability and oil viscosity of 33 cp at initial reservoir conditions. In this case we use a high frequency microwave antenna located 30 ft from the producing well as the heat source. Simulation results presented in this paper suggest that electromagnetic heating may be a good stimulation technique for heavy oil reservoirs with low injectivity or with thin payzones. We identify the parameters which are critical for electromagnetic heating. We also discuss past field applications of electromagnetic heating as well as technical challenges and limitations.
Integration of Technology Supports Preventive Conformance Reservoir Techniques
Authors: Soliman M. Y. , Rester Stephen , Sigal Richard , Everett Don , Johnson M. H.
Published: December 2007

Traditional conformance applications, when defined as the management of unwanted water and gas, normally have been applied late in the life of the reservoir. In these cases, the success of the conformance treatment has been totally dependent upon an accurate description of the reservoir. Obviously, without a proper determination of the reservoir conditions, the underlying reasons for the water and/or gas problems cannot be assessed, and the most appropriate treatment cannot be applied. It has now been shown that a conformance treatment can be even more effective if it is applied early in the life of the reservoir. In other words, a preventive or a proactive conformance treatment may be more successful and less costly to apply than a reactive treatment if analysis determines that the reservoir conditions are such that water and gas production are likely to occur as the field matures.

Thus, since accurate reservoir description is the key to whether a treatment will be effective, regardless of whether applied early or late in the life of the well, it is obvious that the proper diagnostic and analytical tools are critical to the success of any conformance application. This fact will be proven in this paper through use of a database that contains over 900 actual conformance treatments that show that a success ratio exceeding 90% is obtained when the proper diagnostic tools are used.

To apply the concept of preventive conformance, the availability of a diagnostic tool is extremely important. This tool should have the capability to determine the type and location of reservoir fluids and whether the encountered water is mobile. A powerful tool for providing this information is the MRI (Magnetic Resonance Imaging) Logging tool.

This paper shows how coupling reservoir description in general and conformance in particular to MRI technology through the application of MRI logs can benefit the process. It also illustrates the technical and economical value of this technological integration through the use of simulated examples. The simulated examples were created using a commercially available 3-D, 3-phase simulator.
Rotational Toolface Orientation to Facilitate Coiled Tubing Target Acquisition
Authors: Bingham Brian
Published: December 2007

Coiled tubing drilling has proven to be a valuable asset in petroleum recovery; however, the application of this technology has also posed its own unique challenges. One of the greatest challenges has been devising a way to orient downhole toolface without the ability to rotate the drillstring. The operation of the patented indexing tool described in this paper, only one of two currently available on the market, achieves toolface orientation by using available hydraulic forces already present during the drilling process: air, gas, or mud.

Actuation is achieved through a flow-operated orienter. The mud or other sources of hydraulic power drive a cam that rotates the toolface. The design of this tool also helps to ensure actuation accuracy by restricting drilling fluid flow until orientation is achieved. Flow will resume only when the toolface is in the correct position, thus reducing possible errors.

Successfully in use for five years on Alaska's North Slope, the indexing tool has a simple design and yet is durable enough to withstand downhole stresses and operate in virtually any environment. Technical and operational features, and the benefits of those features to drillers are discussed in detail in this paper. The indexing tool has also been used successfully as a coiled tubing fishing tool.

Its unique design and operation makes it a cost-effective technique in coiled tubing drilling and a unique achievement in downhole technology.
The Development of a Coiled-Tubing Deployed Slow-Rotating Jet Cleaning Tool that Enhances Cleaning and Allows Jet Cutting of Tubulars
Authors: Courville Perry , Connell Michael L. , Tucker James C. , Branch Alton L. , Tyre Robert S.
Published: December 2007

Tubular restrictions from scale buildup can significantly reduce hydrocarbon production and the overall production capacity of a well. Before production can be restored, this buildup must be removed. Although scale buildup is a global problem, the material composition and characteristics of scales can vary drastically, even within the same field. Therefore, most tools traditionally used for scale removal cannot efficiently remove scale in all well conditions. This paper discusses a recently developed, customized jet cleaning tool that resolves some of the problems inherent with scale-cleaning operations.

Traditional jet cleaning tools have not adequately controlled jet dwell time, which has severely impacted their operational performance. Depending on the type and hardness of the scale, many removal methods cannot control the jet dwell time required to accomplish scale removal. Because the required jet dwell time increases with the hardness of the buildup material, cleaning efficiency can be measured by the capability of the scale-removal method to control dwell time. A new, slow-rotating jet cleaning tool maximizes jet dwell time without introducing repetitive cyclic effects on a coiled tubing (CT) workstring.

The slow-rotating jet cleaning tool can also be used for cutting tubulars. Previously, tubulars could only be cut by mechanical, explosive, or chemical methods. CT was used either for deploying positive-displacement motors (PDM's) for rotating mechanical cutters or to deploy pressure-activated firing devices that initiated the firing sequence in explosive or chemical cutters. The slow-rotating jet cleaning tool can be used to cut tubulars when limitations exist for other cutters.

This paper discusses the evolution of CT cleaning procedures, alternatives to cleaning with CT, and the design and application of the new slow-rotating jet cleaning tool. Case histories discuss the use of the jet cleaning tool for removing scale and production buildup on tubing walls. The new tool can be used for performing through-tubing cuts and can help reduce service costs for difficult applications, such as those involving long bottomhole assemblies (BHA's). The capacity of the new jet cleaning tool to control jet dwell time and pump abrasive fluids helps reduce the risks, obstacles, and costs associated with traditional cleaning and cutting methods.
A Single Slurry System for Cementing Surface Casing in a Low Fracture Gradient Shallow Gas Area Off Shore Kalimantan
Authors: Hartoni A. , Hobson B. , Huizenga R. , Helmana M.
Published: December 2007

Offshore Kalimantan presents some unique challenges in zonal isolation. Two of the problems include low fracture pressure and a shallow gas zone. To overcome these challenges, the operator had resorted to pumping three different slurry systems, each designed to overcome one specific problem. The three slurries were:

Low-density, gas tight slurry. Low-density filler slurry. Neat slurry.

The three slurry systems caused logistic difficulties in transportation, storage on the rig, job execution, and job design. In designing and executing the job, a good understanding of the actual open-hole size was important. If the hole was actually smaller than predicted, the filler cement would be placed over the gas zone.

During the execution of the job, the same problem could occur if too much filler cement was pumped. If this happened, gas migration was not controlled and a costly remedial job was pumped.

An extensive technical study resulted in the development of a single engineered-particle-size slurry system that simplified the job execution procedures, mitigated gas migration, and improved the quality of the overall cement job. Changes made to the physics of the cementing operations could also be pre-evaluated using an advanced u-tube simulator. Input of well and fluid parameters allowed analysis of the impact and optimization of slurry design prior to actual execution of the first new system trials. Impact of system reengineering effects on pump rates, wash/spacer volumes, surface/downhole pressures, and total job times could be predicted and design improvements made. Case histories are given on the first two successes using this new lightweight technology.
Main Aspects Considered in the Upgrade of a Semi-Submersible Platform to Operate in Ultra Deep Waters as a Dynamically Positioned Drilling Unit
Authors: dos Santos Aldemir Bonfim , Bardanachvili Carlos Alberto
Published: December 2007

Upgrading existing Drilling Units has been considered an attractive option for offshore oil exploitation, since costs and time to be spent at shipyards can be lower than for new building. Moreover, use of a Dynamic Positioning System and automated drilling facilities are essential for the performance of the Unit when operating in ultra deep waters.

The demand of drilling offshore Brazil was the motivation to evaluate the feasibility of upgrading a Mobile Drilling Unit to operate in water depths up to 2500 m, with slender drilling risers.

This paper focuses on the main aspects considered during the basic design phase of the upgrading of a Semi-submersible Drilling Unit as follows: Additional utility systems;New Bilge and Ballast system;Drilling facilities;Increase in Payload;DP system with addition of thrusters;Naval architecture, including blisters, pontoons enlargements, thrusters locations and new compartmentation;Upper hull arrangement;Structural reinforcements;Model testing;Power demand and Generation;Integration between systems;Class Notation.

With all those aspects addressed, the objective of providing a design of a Unit feasible to operate in ultra deep waters has been reached, from safety, structural, stability, station keeping, arrangement and drilling performance points of view.
Enviromental Protection in Drilling Operation Using Minimum Pit and Zero Cost
Authors: Sauman M. , Law Brian , French Christoper P. , Pianca Justin
Published: December 2007

PERTAMINA / Vico Indonesia made the decision to minimize the size of mud pits in order to minimize the environment impact and reduce costs in its onshore drilling operation in East Kalimantan. Vico Drilling use a water base mud for drilling the surface hole and a synthetic oil base mud for drilling the production section. At the time of the decision, all cuttings and mud waste from the operation were dumped into a large pit. Since 1999, new technology has been applied for "reduced pit drilling". The environmental goals were achieved at a cost saving, as the costs are more than offset by cost reductions.

The first stage of the environmental protection project used a combination of additional solids control equipment to recover as much of the liquid phase as possible and improved locations to channel the rainwater. Water-based mud, location drainage, and rainfall were treated using water clarification. This process allowed the clean water discharge from the process to be recycled for the rig operation or disposed to the environment.

The second stage of the project used a special equipment to maximize the recovery of synthetic oil base mud and to reduce the oil content in the cuttings. The cuttings are further processed using bioremediation and landfarming technology to degrade the toxic hydrocarbons to harmless end products on location.

Once the system and waste disposal is proven, the third stage will be for pitless drilling. Depending on the success of the bioremediation, the requirement for other advanced technology such as thermal desorption will be evaluated.

During the project, special effort has been given to confirm the water clarification and remediation results. In order to meet Indonesia regulations and other applicable regulations and standards, water and solid waste are tested to ensure discharges are acceptable. The remediated soil area has been planted with a variety of native plants.

Using the above technology PERTAMINA / Vico Indonesia have minimized the environmental impact in its drilling operation. There is a cost saving as the cost of the service is offset by reduced costs for land, construction, reclamation, and re-greening.
The First Multi-Lateral / Dual Completion Well in Saudi Arabia
Authors: AL-Umair Naji A.
Published: December 2007

Recently Saudi Aramco completed the first multi-lateral / dual completion well with permanent segregated access and segregated production in one of its offshore fields in the Arabian Gulf region. The well presents a technical milestone to the company in the development of multiple reservoir fields. Also it demonstrated how new technological tools could be deployed effectively in an ideal situation to meet both reservoir and production requirements in a very cost-effective manner. Several systems were considered for this particular application which were thoroughly evaluated based on company requirements, cost, and immediate availability. Other considerations such as service company experience, number of jobs performed by service company and technical support were also part of the screening criteria.

This paper presents Saudi Aramco's first and successful experience in the deployment of new acquired technology for the multi-lateral / dual completion systems. The screening criteria for selecting the system as well as the benefits realized and lessons learned from this experience are also discussed.
Modern Total Well Management
Authors: McCoy J. N. , Podio A. L. , Drake Bill
Published: December 2007

The need for oilfield operators to verify that wells are being produced at their optimum capacity and in a cost effective manner is always present. The need to reduce operating costs, increase oil production and increase net income from wells requires an integrated analysis of the pumping system including the performance and interaction of all the elements: the reservoir, wellbore, the downhole pump, the gas separator and the prime mover. The analysis is to be made based on data obtained at the surface without entering the wellbore and must yield an accurate representation of conditions that exist on the surface, within the wellbore and within the reservoir. This paper presents a modern and logical approach to the solution of this problem through the use of Windows based applications and Sigma-Delta state of the art data acquisition hardware.
Integrating Seismic Monitoring and Intelligent Wells
Authors: Mjaaland Svein , Wulff Angelika-M. , Causse Emmanuel , Nyhavn Fridtjof
Published: December 2007

4D seismic is a valuable tool for reservoir monitoring and improved reservoir management. With the introduction of intelligent completion systems arizes the opportunity of a continuous monitoring of the near wellbore formations from the well. Future intelligent well completions may include high-frequency downhole source and sensors to be utilized for active and passive seismic reservoir monitoring. The advantage of such a system lies in its excellent repeatability and high resolution, resulting in more sensitive and detailed reservoir observation and formation evaluation. Specific benefits are monitoring of fluid/gas contact zone movements as gas/water coning, improved reservoir characterization, and optimization of reservoir drainage.

Finite difference seismic modeling was performed to illustrate the advantages and challenges related to continuous in-well reservoir monitoring. The reservoir model was based on log, core and production data, as well as geological information. Rock physical calculations were performed to relate expected variations of reservoir pore fillings to changes in seismic properties. The time-lapse seismograms reveal important features of high-frequency seismic monitoring. Due to high repeatability even small changes in seismic contrast can be resolved at a small scale, hence in-well seismic data provide detailed reservoir information to be combined with conventional 4D seismic results. Moreover, new processing requirements are identified.