bluuebunny/crossref_metadata_2025 huggingface dataset:
Downhole Video Services Enhance Conformance Technology
Authors: Maddox Steve , Gibling Glen R. , Dahl Jeff
Published: December 2007

Conformance Technology can be defined as "the application of processes to reservoirs and boreholes to enhance recovery efficiencies." The purpose of these processes is not to increase production but to reduce and dispose of unwanted bi-products; i.e., water, gas, sand, etc., and the associated costs generated by their disposal.

Conformance technology has been practiced in the oilfield for many years, but it is gaining in importance because of environmental and economic constraints that limit operator options for the disposal of unwanted production. The successful practice of conformance technology is dependent upon a thorough understanding of the downhole conditions in each well, as misinterpretation of downhole data can result in the application of treatment that will not successfully address the problem.

This paper describes applications for downhole video services that facilitate:

Planning of conformance technology treatments Provision of in-process treatment monitoring Confirmation of post-treatment success

Three case histories showing different applications of video services in conjunction with the planning and confirmation of treatments are presented. The first case determined fluid entry under flowing conditions and better defined which zones required treatment. The second case showed that the original well diagnosis was incorrect and that the planned treatments would not be effective, while the third case showed how a downhole video survey was used as a pretreatment analytical tool and later used to confirm a successful treatment.
Horizontal Wells – Are They Worth the Cost?
Authors: Doan Q. T. , Ali S. M. Farouq
Published: December 2007

Horizontal and extended-reach wells are making an important contribution to world's oil production. Well over five thousands horizontal wells and drainholes have been drilled, with approximately fifteen hundreds such wells in Canada. Horizontal wells can be valuable under certain conditions, as discussed in this paper, but they are not necessarily always better than vertical wells. Horizontal well drilling and production technologies, with particular emphasis on their application in naturally fractured reservoirs, are considered in light of the North American and European experience.

The paper also discusses the current trends in horizontal well drilling, production and completion. The increasing use of coiled tubing, multilaterals drilling and underbalanced drilling are described. While horizontal wells are an important development, some care should be exercised in planning afield using horizontal wells, in particular with regard to the subsequent application of secondary recovery methods.
NodalB©: A Unique Program for Optimum Production of Sucker Rod Pumping Oil Wells
Authors: Guirados Carlos D. , Ercolino José M. , Sandoval José L.
Published: December 2007

Sucker rod pumping is the oldest artificial lift method used in production of oil wells. This method is usually designed and analyzed with the assistance of programs based on simplified models, such as the API RP 11L1,2, or with a wave equation simulator3,4,5. In many cases, however, a technique that permits consideration of the inflow and outflow performance of the well is a more efficient way to design and analyze an oil well. This technique, referred to as Total Analysis or System Analysis (SA), has been successfully applied to flowing and artificially lifted wells.

This paper presents a computer program developed by Intevep S. A., called NodalB©, created to perform the SA of sucker rod pumping wells. NodalB©'s unique characteristics make it a competitive program in today's market of design and optimization software. This program allows consideration of the inflow performance of the reservoir depending on the drilling scheme, either vertical or horizontal, and determination of the sensitivity of the rod pumping system to its most relevant parameters, such as: pumping speed and stroke, pump diameter, gas oil ratio, gas separation efficiency, tubing diameter, pump depth, rod string design, oil viscosity, injected diluent (diesel, kerosene, etc.) ratio, water cut, reservoir pressure, productivity index, and different production schemes (i.e. production through the tubing or through the casing-tubing annulus). These features show the power of this program as a predictive tool. NodalB© is specially applicable to design, optimization and troubleshooting of heavy and viscous oil wells, taking into account the viscosity effects in the rod pumping system.
PC-Based Interactive Technical Training
Authors: Novotny Rudolf J.
Published: December 2007

Write a comprehensive training manual on a technical oilfield subject, print it, and send it around the world. Six months later only a few individuals have taken the time to review, much less study the contents. Write an interactive, interesting computer program, put it on the company BBS system, and before long, every PC in the company has a copy.

Computer interactive training has been common place for years, but generally its focus is training on computer software. This paper describes a PC-based program that facilities the study and training of technical or company-related information via interactive computer operation. The program is versatile, compatible with any level of PC hardware, and easily updated.

The program prompts answers to multiple choice questions about the technical information. To prevent memorization of the questions and answers, each training session consists of answering 25 questions randomly selected from a pool of 200 questions. This approach provides the student with multiple training sessions with minimal duplication.

This paper describes the methodology and application of this type of computerized training. An explanation of the programming logic and an example of a sample session is provided.
Multidisciplinary Approach to Successful Implementation of Production Information System (PRISM)
Authors: Shariff Mahd Ridza Md , Gapalakrishnan Sri Ganesh , Francis Nelly , Mansor Raslan Abu , Daniel Davies
Published: December 2007

A company wide corporate and regional production database supporting all production areas was envisaged critical to the current expansion within Petronas Carigali Sdn Bhd (PCSB). A multi disciplinary project team was thus formed to analyze the requirements prior to developing, testing, implementing and training users.

PCSB has currently evolved into a mature E & P company on par with other E & P companies within the region. This expansion necessitates a common Production Information System for the efficient dissemination of vital Production Information for Production Surveillance, Reservoir Management, Reserve Assessment, Special Studies and Standardized Group-wide Reporting.

This paper will discuss all the phases involved in the project which includes Systems Requirement Study, Data Migration, System Development, System Implementation and Post-Implementation Plan.
The Design of a Submerged, Buoyant, Anchored Transoceanic Pipeline for Transporting Natural Gas
Authors: Savage Godfrey H. , Marsden Sullivan S. , Street Robert L. , Boutin Pierre L.
Published: December 2007

The particular case of using a submerged, buoyant pipeline, anchored below the surface energy effects, to transport natural gas from North Africa to Southern Europe is analyzed. A design, mathematical model of the pipeline with its anchoring system is presented. A typical segment of the model is analyzed to determine the maximum stresses developed in the pipeline and in the anchoring cables and the maximum motions of both the pipeline and the anchoring cables when subjected to forces due to ocean currents, surface wave action and buoyancy. The method of imaginary reactions, combined with the method of successive approximations, is used in these static analyses. Computer programs used in the analysis are referred to, but not presented. The design, mathematical model is given structural authenticity because it is based upon full scale ocean tests of the basic trimoored anchoring station component using steel cables and glass floatation units where the system withstood measured ocean current and wave forces with measured motions of only a few feet as predicted. A mathematical model of the ocean current velocity versus depth that exists for the Mediterranean location is presented. It is based upon current measurements that have been made in the area and information documented by physical oceanographers who have studied the area. This model is used to determine the drag forces used in the analysis of the structural model of the pipeline and its anchoring system.

With consideration for specific limitations on cable sizes, pipe welding speeds, and other state-of-the-art constraints on off-shore construction, and assuming several rate levels of gas delivery, the several probable diameter pipelines are incorporated into specific pipeline and anchor systems and analyzed to determine the required cable spacing, cable sizes, anchor sizes and the other important cost determining factors, including installation costs.

Finally, for various levels of predicted market demand (maximum gas rate), the preliminary capital investment, costs, and preliminary capital investment, costs, and return on investment are estimated. Critical considerations such as safety factors selected and the need for preventative maintenance are incorporated, quantitatively, in this economic evaluation.
Unique Simulation Development Enhances Operation of Downhole Well Test Tools
Authors: Schwendemann Ken , Beck Kent
Published: December 2007

Oilfield technology has experienced such rapid advancement during the last decade that end users often find themselves lacking in the ability to understand and properly use the newly designed equipment; thus, they are unable to take full advantage of the benefits that the enhanced systems offer.

This paper will discuss the development of a new simulator that solves this problem by providing the oilfield end user with on-line ability to understand and properly operate newly designed equipment.

The simulator uses a very natural graphical user interface to convey complex technical information, and its usage enables a broader range of developers to produce quality simulations that would previously have been limited to development by the expert programmer.

In addition to a discussion of the development of equipment simulator methodology, the many uses of the technology that have been identified to date will also be presented. These include: Conveying complex technical informationReducing personnel training timesDesigning well testsReviewing design processes to verify design parametersVerifying customer requirementsAllowing operators to "practice" the well test before it is applied

The use of the equipment simulator promotes better understanding of equipment used for servicing and operation of the rig and well. With overall goals depending upon reductions in costs of drilling and completing wells, a better understanding of equipment helps ensure safer, more efficient operating conditions, which in turn, increases the probability for realization of economic goals.
Well Test Analysis by Reservoir Simulation Coupled with a History Matching Program
Authors: Hwan R. Randy
Published: December 2007

A procedure of well test analysis using a reservoir simulation model coupled with a history matching program has been developed, The history matching program used in this study is called "Adaptive History Matching (AHM) System" which was developed by Scientific-Software Intercomp (SSI) with the participation of Texaco and two other major oil companies. AHM was designed to help the engineer deal with the problems of history matching reservoir performance data with a reservoir simulator. Pressure data measured in well test is directly history matched with the current method without converting to dimensionless terms or taking the logarithm of the data.

The history matching system used in the current procedure is based on Bayesian inference. Bayes’ theorem provides a process of learning from experience and shows how knowledge about the state of nature can continually be modified as new data becomes available. Four cases of well test analysis are presented in this paper. They include a single well test, an interference well test, a multi-layered reservoir case, and a horizontal well test. In each case, the conventional well test results are included for comparison with those of the current method. It only requires a few simulation runs for the current procedure to obtain the well test results.

The interference case shows that the pressure data of the observation well during injection and shut-in periods at an active well are matched by the current method, The analyses by conventional methods can only be conducted during either the build-up or the shut-in period. In the multi-layered case, with crossflow at the wellbore between the high and low permeability layers, the current method is capable of determining the permeabilities of these layers individually. In contrast, the conventional well test analysis only provides a composite permeability value for a multi-layered reservoir. The current procedure is also applied to the horizontal well test analysis. The horizontal and vertical permeabilities are analyzed simultaneously.
Pollution Problems in the "Oil Patch"
Authors: Rold John W.
Published: December 2007

Throughout much of the "oil patch," water truly exemplifies the economic, sociologic, political and ecological lifeblood of the community. The permanent supply of usable water, on which the arid West depends for survival, faces many hazards. Currently, much available water exceeds or is rapidly approaching Public Health limits, and the tolerance level of the inhabitants.

Water enters an area as river flow or rainfall. It goes underground by natural seepage or irrigation where it percolates until it surfaces at natural springs or wells (domestic, irrigation - municipal or industrial) to re-enter surface flows. Normally, the cycle is repeated many times. Each cycle degrades the water quality. Although oil field operations contribute a small proportion to total degradation of the hydrologic system, each incident of oil field pollution is specific and highly newsworthy. When attempts to clean-up waters are made, the oil industry provides the first and most vulnerable target. Oil field practices can and do pollute water, mainly by increasing total dissolved solids (principally chlorides and sulfates), but also by releasing crude oil.

Ground water pollution is often difficult to prove and may not appear immediately. Conversely, its effects may persist for many years. Pollution may occur from:

Evaporation Pits. Regardless of the concentration of brine entering a pit, the only substance leaving the pit by evaporation is pure distilled water vapor. Everything else remains behind forever or enters the water system either by seepage through the bottom of the pit or overflow. In Colorado during 1969, 27,000,000 barrels of water (1,110 to 35,000 ppm salinity) went to unlined pits. A 1966 detailed study of a ground water basin in NE Colorado showed that one small brine pit contributed a 27 ppm per year salinity increase to the entire ground water basin. Insufficient surface casing. Any surface casing which is not set below, and does not seal off all fresh water aquifers constitutes a pollution hazard. Any injection system. Waste disposal or water floods constitute a hazard; not only from casing leaks but also from cross-formational flows through natural or induced fractures.
The Application of Petroleum Engineering Science And Technology to Subsurface Disposal of Liquid Industrial Wastes
Authors: Donaldson Erle C. , Johansen Robert T.
Published: December 2007

The direct application of oilfield technology to subsurface disposal of industrial wastes has directed attention to numerous technical problems. These arise because of (a) the special design and operation required for wells intended for disposal of highly corrosive fluids, such as pickle liquor, from steel companies; (b) special precautions that must be taken to avoid injection of an immiscible phase with the aqueous waste (a small percentage phase with the aqueous waste (a small percentage saturation of an immiscible fluid in the disposal formation will seriously decrease the relative permeability to water); (c) special treatment of the formation and waste when swelling clay is present in the disposal formation; and (d) the limiting volume of some formations. Some of these problems encountered by chemical industries are described.

Introduction

Subsurface disposal of liquid waste has been practiced by the petroleum industry since about 1920 when it was applied to oilfield brines. Currently the U.S. oil industry injects about 17 million B/D into subsurface formations. In contrast, a survey of liquid waste injection by the chemical industry, made in 1962 by the U.S. Bureau of Mines, showed that 32 wells were being used to inject 136,000 B/D of industrial waste. Estimates from recent national survey, indicate that about 150 wells are being used to inject approximately 675,000 B/D of industrial wastes into geologic formations ranging in depth from 1,000 to 8,000 ft. Thus, in 8 years the volume of industrial waste injected underground has increased five times.

The successful injection of waste by the chemical process industry shows that subsurface waste disposal offers a solution to extremely difficult liquid waste disposal problems. Concentrated acid wastes, caustics, problems. Concentrated acid wastes, caustics, solutions of salts, organic phosphates, phenols, chlorinated hydrocarbons and mixed organic and inorganic wastes are being disposed of economically by injection into geologic formations.

There are many advantages of subsurface over surface methods of waste disposal. Capital investment and operating costs are lower, the surface area required for the plant is less, seasonal temperature variations plant is less, seasonal temperature variations have less effect on the system, chemical treatment of the waste is minimal, and generally the only physical treatment required is filtration.
Dynamic Effects of Foamy Fluid Flow in Sand Production Instability
Authors: Geilikman M. B. , Dusseault M. B. , Dullien F. A. L.
Published: December 2007

As a major component in the development of better flow models for the "cold production" process in heavy oils, formation of a foamy fluid phase during flow of a liquid containing dissolved gas toward a wellbore is considered. The appearance of gas bubbles in the flowing fluid is described by the theory of nucleation. Unlike previous approaches, the foamy state is interpreted as a metastable state which starts developing at pressures below the bubble-point of a gas-fluid phase diagram. The amount of gaseous phase is determined kinetically, that is, by the rate of nucleation. Mass balance analysis for the compound foamy fluid gives the spatio-temporal evolution of the foamy zone which starts growing around the wellbore. Fluid pressure in the foamy zone exhibits a steeper gradient, compared to the non-foamy flow. The conditions of sand production instability via tensile failure at the foamy front are also determined, and this constitutes a condition for liquefaction and loss of effective stress in the granular medium.
Study on Technology of Mixing Active Water in Shanjiasi Heavy Oil to Reduce Viscosity
Authors: Chen Shen , Lijie Yuan
Published: December 2007

The study present in this paper aims to solve the problems happening in the heavy oil production wells with steam stimulation in Shanjiasi, Shengli Oilfield, that at the end of a circle, temperature fall causes the viscosity of the production liquids to increase significantly, which leads to various accidents. By analyzing the. laboratory test of the viscosity reduction and rheology of the heavy oil, etc., the feasible mechanism of mixing active water in heavy oil to emulsify and the relevant downhole prodution technique are obtained. With the technology of injecting active water down the annulus in three wells, the stable production is insured in the late production period of heavy oil wells with steam injection, and the production period is prolonged with a favorable economics.
Benchmarking Heavy Oil Operations - A Step to Improved Profitability
Authors: Sonmor Randell G.
Published: December 2007

This paper discusses the application of benchmarking to Heavy Oil operations in Western Canada. Benchmarking is used in many industries to compare performance among competitors. Benchmarking can enhance a company's competitive position which can lead to increased profitability and added value for the shareholders. The Ziff Energy Group, using its ten years of benchmarking the Western Canadian Exploration and Producing Industry, prepared an in-depth Heavy Oil Benchmarking Study with the participation of key Western Canadian heavy oil producers. The study covered the period January 1 to September 30, 1993. The report focused on benchmarking the main cost categories of "operating costs" for approximately 140 heavy oil fields. The classifications Included; well servicing, repairs and maintenance, property taxes and lease rentals, fuel and utilities, contract services, labour, emulsion trucking, sand disposal, and miscellaneous. Given the diversity in oil quality, reservoir characteristics, and royalty regimes in Western Canada the fields were benchmarked for each of the four main heavy oil producing regions: (1) Western Saskatchewan (2) East-Central Alberta (3) Cold Lake and (4) Southeastern Alberta. The study provides the producer with a practical tool to compare it's operating costs with competitors’ costs in the same geographic area. Such comparison can be valuable in developing plans to lower costs and increase profitability.
New Technology of Heavy Oil Profitability Increasing
Authors: Belonin M. D. , Gribkov V. V.
Published: December 2007

The offering method of development of the high-viscous oil fields foresees the territorial and technological combination (TTC) of production and refining of them. It permits, on the basis of new technology, to carry out the closed process - from receipt of raw, as producing oil, to production of the finished products. Simultaneously, the heavy fractions of refining oil and smoke gases from a refinery plant are injected in a reservoir for combined impact to it.

Application of this technology can provide:

– oil recovery coefficient - 0,5 and more, – degree of oil refining - 80 % and more, – increasing of ecological indices in 10 times and more in comparison with traditional technologies, – increasing of economical efficiency of oil production and refining in 2 times and more, – recovery of associated useful components (sulfur, vanadium, nickel, gypsum etc.) as commercial products.
Treatability of Refinery and Petrochemical Wastes
Authors: Carnes Billy A. , Gloyna Earnest F.
Published: December 2007

The characteristics of wastewaters from petrochemical plants and refineries vary petrochemical plants and refineries vary considerably. Both the quantity and quality may fluctuate significantly within a plant and, between similar facilities, the difference may be even greater.

This paper describes methods of characterizing refinery and petrochemical waste-waters, provides a sequential approach to the development of design data, and describes some design relationships.

Introduction

The refining and petrochemical industries are among the largest water users in the United States. However, water conservation measures combined with process modifications and in-plant control practices have resulted in decreased water requirements within both industries.

The production of petrochemicals, which are defined as those chemicals which originate either totally or in part from petroleum, natural gas, or liquefied petroleum gases, increased five-fold during the period of 1945 to 1960 in 1955 the total production of petrochemicals constituted 24 percent by weight of the total chemical production; and, it is estimated that in 1970 the total production was 41 percent. Estimates indicate that about 500 new petroleum products are introduced to the petroleum products are introduced to the market every year and there is little doubt that the industry will continue to grow and diversify.

It is axiomatic that pollutants discharged from the petroleum industries will increase proportionally and that adequate facilities proportionally and that adequate facilities must be provided to preclude any harmful effects from wastewater effluents.

The successful treatment of wastewaters discharged from refineries and petrochemical plants is predicated on many factors and plants is predicated on many factors and while it is recognized that each industry poses its individual problems, there is a poses its individual problems, there is a logical approach to selecting efficient treatment processes.
Conceptual Steamflood Designs Using Horizontal Wells to Maximise Project Profitability
Authors: Escovedo B. M.
Published: December 2007

Although horizontal wells have amply shown that they improve productivity and accelerate production at a reduced cost per barrel in non-thermal applications, their ultimate impact on thermal recovery is far from fully explored. This work investigates the impact of customising the geometry of horizontal wells for steamflooding to suit a given reservoir architecture. To optimise the well's geometry, consideration first has to be given to the expected shape of the steam zone. Given the shape, wells can be arranged to either maximise the sweep efficiency of steam before steam breakthrough and/or to minimise the negative consequences of steam interference in producing wells afterwards. Three conceptual steamfloods are described which demonstrate the benefits offered by horizontal wells and illustrate how the economics of implementing and operating such floods can improve over historical designs.
The Incineration of Carbonaceous Wastes in Fluidized-Bed Systems
Authors: Smithson G.R. , Wheeler C.M.
Published: December 2007

Fluidized-bed systems have been used in many industries since the first fluidized-bed catalytic cracking unit was installed by the petroleum industry in the late 1930's. Industrial uses include the roasting of sulfide ores, the drying of heat sensitive materials, and many others.

The initial attempt to utilize this technique for the disposal of carbonaceous liquid wastes from the paper industry began about ten years ago with a bench-scale experimental study at the Columbus Laboratories of Battelle Memorial Institute. This research was followed by pilot-scale investigations which led to the installation of the first Container-Copeland commercial unit at the Carthage mill of Container Corporation of America.

Since the first commercial installation, the system which initially was developed has been adapted to the treatment of wastes from several types of pulping operations as well as to the disposal of other carbonaceous industrial wastes. Included in the applications are three which are of direct interest to the petroleum industry:

(1) The disposal of sulfuric acid sludges;

(2) The incineration of oily and caustic refinery wastes; and

(3) The disposal of sludges from the biological treatment of petrochemical wastes.

Introduction

Many industrial uses have been proposed for fluidized-bed systems since this technique was proposed by C. E. Robinson about a century ago. However, it wasn't until the late 1930's that the first commercial fluidized-bed unit involving a gas solids mixture and utilizing elevated temperatures was installed. This installation was the beginning of the use of fluidized-bed catalytic crackers by the petroleum refining industry. Since then fluidized-solids technology has been firmly established as a useful and very valuable industrial tool. The development of this technology for use in many industries has taken years for fruition and new applications continue to be extensively explored.

After its adoption by the petroleum industry, fluidized-bed technology was successfully applied to many operations in other industries where careful control of temperature and gaseous atmosphere and simplicity of operation were needed.
Geomechanics Issues of Steam Assisted Gravity Drainage
Authors: Chalaturnyk Rick , Scott J. Don
Published: December 2007

After successful testing and full scale implementation of the steam assisted gravity drainage (SAGD) process at AOSTRA's (now Department of Energy, Oil Sands and Research Division) Underground Test Facility (UTF), many operating companies are applying this recovery process (or variations thereof) in bitumen and heavy oil projects. The thermal SAGD process with adjacent sets of wellpairs provides a process geometry where the geomechanical response of an unconsolidated sand reservoir may have an impact on the efficiency of the recovery process. This paper describes a series of numerical analyses which illustrate how fluid pressure increases and thermal loading combine to create an optimum stress environment for shear failure of unconsolidated sand formations. Shear failure in dense unconsolidated sands results in a volumetric increase in sand pore volume due to dilation of the sand grains.

To date, bitumen production rates for the SAGD process have been history matched for the UTF Phase A and Phase B tests by increasing the absolute permeability within the formation to a very high value; typically to the maximum value within a range of possible values. It will be shown that for the UTF geometry, absolute permeability increases resulting from dilation in advance of the growing steam chamber is likely a factor in the SAGD process. Due to the nature of SAGD, however, reservoir modelling for UTF scenarios are not be significantly effected since dilation in advance of the steam chamber would create the same "absolute permeability" effect as selecting an initially high absolute permeability value. For different reservoir conditions, such as stress conditions, or wellpair spacings then at the UTF, not including geomechanical phenomena in process simulations may adversely affect the results.
Horizontal Well Application in a High Viscous Oil Reservoir
Authors: Zhou Guanghul , Zhang Rul , Shen Dehuang , Pu Halyang
Published: December 2007

This paper presents the results of scaled model experiments which were conducted to study the possible application of horizontal wells and were used to assess and compare the configurations of horizontal/vertical wells for a type reservoir which is characterized by high viscous oil (11,000 mPa · s at reservoir temperature). The mobility of high viscous oil is limited, so conventional vertical well steamflood is uneconomical. But reservoirs of this type are common in China, thus it is imperative to develop recovery strategies which are likely to succeed in the field, which was the objective of this research.

The scaled model had two vertical wells and four horizontal wells which corresponded to injectors or producers. Experiments of many types of horizontal/vertical well configuration were conducted. Some of which gave favorable results. The horizontal injector-horizontal producer configuration was the best one for the high viscous oil of this study. Horizontal well steamflood can be effective for reducing or preventing steam override and steam channel, the final oil recovery was 54% compared with 35% for a baseline experiment using vertical well steamflood. When steam flow rate increased from 140 cc/min to 170 cc/min, the final oil recovery increased from 57 % to 62%. The preheat phase by steam circulation further improved the final recovery to 78%. The SAGD (Steam Assisted Gravity Drainge) process of horizontal injector-producer configuration not gave good results, it was a very slow process and it's effective drainage area was smaller. The steamflood of vertical/horizontal well configuration was unsuccessful. Temperature measurement and theoretical analysis were used to interpret the results obtained.
Waterflood Optimization of the Buffalo Coulee Bakken Heavy Oil Pool of Southwestern Saskatchewan
Authors: Ko Stephen C. M. , Domier Duane B. , MacDermott Richard N.
Published: December 2007

Since 1969, a waterflood scheme has been implemented in the Bakken sand heavy oil reservoir in the Buffalo Coulee field of southwestern Saskatchewan. Even with 20-acre well spacing in the waterflood area located in section 22-32-24 W3M, projections of oil recovery appear to be low, especially in the northern half of the section where much of the original gas cap still exists. Reservoir simulation was employed to investigate the potential of well spacing reduction from 20-acre to 10-acre by infill drilling, the merit of additional water injection into the reservoir, and the effect of gas cap blowdown on oil recovery. A reservoir model representing section 22 and the surrounding waterflood area was calibrated by history matching the historical production and injection performance of the 48 wells in the study area. Based on history match results, the shale layer between the oil pay and the gas cap provides a vertical permeability barrier in the gas cap area of the reservoir. This was confirmed by the findings of a recently drilled well where injected water was found to have completely flushed the gas cap, resulting in water currently situated on top of the oil zone in that portion of the reservoir. Based on performance predictions conducted on the calibrated reservoir model, the current 20-acre well spacing is adequate for the waterflood scheme in the pool, since infill drilling with either vertical or horizontal wells will not recover any significant incremental oil reserves. Furthermore, blowing down about 14.9 × 106 m3 of gas from the gas cap will have no detrimental effect on the estimated oil recovery of about 18% of the original oil-in-place (OOIP), based on current water injection rates in section 22. If water injection in section 22 is increased by about 50%, oil recovery from section 22 can be improved to about 22% of the OOIP, corresponding to an incremental oil recovery of about 76,000 m3, or 4% of the OOIP.
An Update of Steam Injection Operations at Naval Petroleum Reserve No. 3, Teapot Dome Field, Wyoming: A Shallow Heterogeneous Light Oil Reservoir
Authors: Doll T. E. , Luers D. K. , Strong G. R. , Schulte R. K. , Sarathi P. S. , Olsen D. K. , Hendricks M. L.
Published: December 2007

The Shannon light-oil (32–34° API gravity) steamflood at Naval Petroleum Reserve No. 3, (NPR-3) Teapot Dome field, Wyoming, was initiated in 1985 as a result of favorable production response to steam preheating in the in situ combustion pilot earned out in the early 1980's. Favorable but mixed success of two 10-acre steamflood pilots led to commercial scale operation in 1987. To date, the steamflood project has steamed 210 acres, 90 acres of which is currently being steamed with three 50 MMBtu/hr steam generators. The performance of the steamflood is reviewed in light of the dominant role that the reservoir's complex geology plays, since both injection and production wells are greatly influenced by the localized, highly heterogeneous geology of the consolidated, tight, faulted, and extensively fractured sandstone composing the Upper and Lower Shannon. Pattern step out is dominated by the geologic conditions that dictate each pattern's operation. Economics, mandates for profitability, and budget constraints have influenced the method by which the steamflood has been managed. Investigations of lower injection rate, variation in steam quality and the associated production response, as well as improvements in heat management techniques, are discussed. Increasing steam quality in pattern 5A led to incremental oil production of 44 B/D and a 2.5 times return on investment on the incremental gas used to fire the steam generator. Optimization of the steamflood depends upon accumulating and using information from pattern-specific operations.
Optimization Simulation on Steam Drive in Le'An Oilfield
Authors: Guanghe Li , Xiaolin Yu
Published: December 2007

Ng2 formation of fault block Cao-20 in Le'an Oilfield is a sand gravel heavy oil pool. Numerical simulation was run on two well patterns of inverted 9-spot with different lithology and well spacing as pilot areas for steam drive test. On the basis of history match of huff and puff with 3-D multi-well and multi-cycle, the prediction of simulation of thermal recovery is combined with the method of input and output using two type of tubings, the right time converting to steam drive and operation conditions for steam injection was optimized from the economic point of view. By integrating the research results, the optimum recommendation for the field has been put forward. In order to improve the steam drive recovery, the prediction on the result of infilling well pattern and minimizing the downhole flowing pressure of producers has been made. Moreover, the analysis of displacement mechanism of steam drive period, evaluation of the result of steam drive, and comparison of the similarities and differences of geology and production of two well groups have been made.
Experimental and Numerical Simulations of a Novel Top Down In-Situ Combustion Process
Authors: Coates R. , Lorimer S. , Ivory J.
Published: December 2007

A new in-situ combustion strategy, the top down process, is currently under detailed laboratory study. The process, aimed at overcoming some of the problems that have restricted the successful application of in-situ combustion in oil sand and heavy oil formations, involves the stable propagation of a combustion front from the top to the bottom of a reservoir, exploiting gravity drainage of the mobilized oil to a lower horizontal well.

Operational parameters that have been investigated and presented here include: air injection flux, degree of pre-heating, internal steam flood pre-heating and injection of normal air versus injection of oxygen enriched air.

To compliment the experimental investigation, the thermal numerical simulator STARS has been applied to the in-situ combustion process by incorporating reaction kinetics for Athabasca oil sand. A successful history match of an experimental test is presented accompanied by a discussion of application of the model to field scale,
Design of a Steam Pilot in a Fractured Carbonate Reservoir - Qarn Alam Field, Oman
Authors: Macaulay R. C. , Krafft J. M. , Hartemink M. , Escovedo B.
Published: December 2007

Steam injection has been identified as the most promising recovery method for the intensely-fractured carbonate Shuaiba/Kharaib/Lekhwair reservoir in Qarn Alam, Oman. The reservoir contains 213 million m3 of heavy viscous (16 °API, 220 cp) crude, however the ultimate recovery efficiency under primary recovery is expected to be only 2 % of stock-tank oil initially in place (STOIIP) because of the strong natural aquifer drive via the fracture system and the oil-wet nature of the rock. An intensive programme of analytical, experimental and reservoir simulation studies has been carried out in order to quantify the potential gains from a thermally-accelerated gas-oil gravity drainage (GOGD) process, and to design and interpret a pilot project in the crest of the reservoir. Steam injection is expected to raise the recovery factor to 20 % or more, but there are large uncertainties associated with the performance of the process. The pilot project will test the application in the field commencing late 1995 and is planned to last for about five years.
The Feasible Conditions Study of Steamflooding for Heavy Oil Reservoirs In China After Cyclic Steam Injection
Authors: He Z. , Zhang R. , Pu H. V. , Ren X.
Published: December 2007

China is rich in heavy oil reserves. In recent ten years, the production of heavy oil has rapidly grown through application of steam injection and the annual production reached up to 11. 9 million tons in 1993. At present, with the increase of cycles of steam injection, the effectiveness becomes poorer and the challenge of changing steam stimulation into steamflooding has to be confronted. Because of heavy oil reservoirs in China characterized with complex geological conditions, deeply buried, multi-layers and serious heterogeneity, especially some complicated conditions occurring in steam cycling, the effectiveness of steamflooding pilots has not been ideal commonly. Therefore, it is urgent to study and determine the comprenhensive conditions at which the reservoirs are feasible to be converted from steam cycling to steeamflooding at the present technological situation.

In this paper, based on three typical types of heavy oil reservoirs, systemetic studies have been conducted to investigate the effects of oil viscosity, oil formation thickness, vertical permeability difference, reproduction ratio of injected water in steam cycling and channelling path etc. on steamflooding effectiveness. Then, a practical screening criterion of steamflooding is proposed to provide technical bases for the conversion.
Prediction of Technological Properties of Tatarstan Natural Bitumens on the Basis of Chemical and Geochemical Characteristics of Their Composition
Authors: Kayukova G. P. , Romanov G. V. , Arbuzov A. E.
Published: December 2007

This paper is devoted to solution of problems connected with forming deposits of heavy oils and natural bitumens in Permian sedimentations on the territory of Tatarstan and to questions of prognostic evaluation of their technological properties in relation to degree of their natural transformations. Comparative investigation of composition and properties of their various representatives (heavy oils, malts, asphalts and asphaltites) occurring on drill log and proved area of Permian producing deposits on the territory of m Tatarstan in depth interval from 1 to 349 m was carried out, in connection with solution of problems on preparation of natural bitumen fields to development. The systematization of studied samples recovered by both natural inflow from wells and their extraction from bitumen saturated rocks of various age and mineralogical composition by oil-bitumen-bearing complexes, and within the last ones, by relation to local erosion basis, allowed to reason that characteristic changes in the composition bitumens leading to formation of their various chemical types are determined mainly by biodegradation process presenting practically in all oil-bitumen-bearing complexes and, especially, enhancing in carbonate reservoirs and horizons consisting of fragmental terrigenous sedimentary rocks undergone the washout and inluence of external factors.

References and illustrations at the end of paper

It was shown that biodegradation processes leading to absence of light hydrocarbon fractions in their composition, including normal and isoprenoid alkanes, and predominance of resin- asphalt compounds enriched by hydroxyl and ester oxygen, along with sulfur and nitrogen atoms, determine technological properties of natural bitumens during their recovery and processing.
The In Situ Formation of Heavy Oil Emulsions
Authors: Cuthiell David , Green Kirk , Chow Ross , Kissel Gerald , McCarthy Clare
Published: December 2007

Heavy oil is commonly produced in the form of water-in-oil emulsions. It has long been debated whether the emulsions are formed in the reservoir, and if so, what effect they have on the recovery process. This work examines the conditions under which water-in-oil emulsions can form in situ, and their flow properties.

A number of experiments have been carried out in which water and oil were injected as separate phases into a sandpack, and the produced oil analyzed for emulsified water content. We find that emulsified water content is small at low injection rates, but that above some threshold rate, the water content rises rapidly. Dependence of the threshold rate on oil type, oil viscosity, water;oil ratio, pack permeability and pack wettability have all been examined.

Our results suggest that oil phase capillary number, Nc, defined as (oil velocity)x(oil viscosity)/(oil-water IFT) is a natural dimensionless parameter to describe the emulsification threshold. For oil viscosity much greater than that of water, and permeability of the order of a few darcies, threshold Nc is between 104 and 10−3. Such capillary numbers are commonly encountered in near-wellbore flow during heavy oil recovery operations.

Experiments comparing a reservoir oil with mineral oils show similar threshold capillary numbers. The threshold increases with permeability of the medium and is significantly lower in oil-wet compared with water-wet sand. Preliminary results indicate that a significant reduction in effective mobility of the oil phase occurs when emulsification takes place.
A New Rig for Lean Times: NDES For Brent Charlie
Authors: Wehling B. , Franzenburg C. -P. , Gmyr P. , Bosse D.
Published: December 2007

The criteria established for proceeding with the Brent Charlie platformNew Drilling Equipment Set (NDES) are safe operation, fitness for purpose, improved workenvironment, reduced rig crew and cost effective design. The project is being implemented with an EPC (Engineering, Procurement, Construction) Contract by a JointVenture (JV) between a German drilling and oilfield systems engineering and construction company and a British fabrication company.

Following the successful demonstration of a semiautomated rig for the Continental Deep Drilling Project (KTB) in Germany, the operating company was satisfied that incorporation of similar state-of-the-art drilling systems technology in the NDES would underpin the economic case for this project.

The transfer of land based technology to offshore applications will be appropriately profiled.

The drilling rig is tailored to meet the present and future needs on the Brent Charlie platform. This rig is the response to the specific requirements of the drilling industry, namely - advanced technology, cost within reasonable limits, and the highest possible safety standards.

The principle design features are remote operations from an enclosed operator's cabin where the driller's and assistant driller's controls, including pipe racking, are all powered functions, together vyith advanced and proven drilling technology and equipment such as handling drill pipes in triples, and making up or breaking out of triples simultanesouly whilst drilling. Proven state-of-the-art automation systems will greatly improve the cost effectiveness of the platform. Ultimately this will provide faster drilling times, provide a safer drill floor working environment, reduce down times, and reduce the number of drill crew required to operate the rig. Many of these systems can be easily incorporated into existing rigs.

The relative benefits and cost savings of the various systems will be presented.

Conceptual engineering design has recently been completed. Detailed drilling systems engineering, procurement and manufacture is now being carried out by the JV team. The partners' commitment to the industry CRINE initiative has achieved further economies. Fabrication and installation of systems and equipment will be carried out in Scotland where the rig will be on display during the commissioning activities. The final completion stage will be during the SPE conference in September, ready for sailaway in December 1995.

The Brent NDES is designed for a working life of approximately 25 years with an anticipated rig shutdown time for maintenance of no more than twoweeks per year and is equipped to handle all present and future drilling operations. The result is a unique drilling rig that not only surpasses all the technical requirements, but is also economical to operate.
Cost Effective Well Abandonment
Authors: Jordan Russell , Head Philip
Published: December 2007

Well abandonment is now becoming an important consideration for many operators, particularly in ex-pensive offshore locations. The traditional methods are very expensive to apply, and it is important to remember have a negative economic impact, other than good housekeeping.

An innovative technique has been developed to en-able all the well casing annuli to be permanently sealed in a single operation. A simulated well aban-donment using this technique is planned for the sum-mer of 1995 and the results will be presented together with time analysis and cost estimates.