bluuebunny/crossref_metadata_2025_split huggingface dataset:
Progressing Cavity Pump (PCP) Behavior in Multiphase Conditions
Authors: Bratu C. 
Published: January 2008

Abstract
In operation, the Progressing Cavity Pumps (PCP) boosting gaseous multiphase mixture faces reliability issues that can be summarized as follows: the pump pressure is developed by the stages nearest the discharge, then the high pressure gradient causes heat to build up which commonly results in premature failure of the elastomeric stator. This paper first describes our recent testing program performed with an industrial PCP in multiphase conditions, and then presents a new analytical model that describes the thermo-hydraulic-mechanic processes which occur when attempting to pump multiphase mixtures. The objectives of our program are to: (1) examine the PCP system operating at high gas volume fraction, (2) analyze the pumping performance (delivered pressure, flow rate, and gas void fraction) and, (3) describe the overheating generated when the gas is compressed. This paper also describes our PCP experimental program and presents resulting experimental datas which clearly show the correlation between the pressure distribution and the heat along the pump. We formally explain this phenomenon by proposing a new analytical model that evaluates the stator degradation and failure risk. This paper should help operators and manufacturers to design pumps with better system's Mean Time Between Failure (MTBF) performance.
Pressure Variations Inside the Hydraulic Fracture and Its Impact on Fracture Propagation, Conductivity, and Screenout
Authors: Daneshy A. A. 
Published: January 2008

Abstract
Field measurement of fluid pressure inside hydraulic fractures have shown rapid pressure decline along fracture length. The consequence of this pressure profile is rapidly tapering fracture width. This means that a disproportionate volume of fluid and proppant injected inside hydraulic fractures remain near the wellbore, thus creating excessive near wellbore and substantially less far field fracture conductivity. This explains why history matching of oil well productions yields much lower effective fracture lengths than gas wells, since oil wells because of their higher permeability require higher fracture flow capacity.
The rapid tapering of the fracture width also restricts the movement of the proppant inside the fracture, causing its accumulation near the wellbore. As the treatment progresses, and if sufficient proppant volume has been injected inside the fracture, the near wellbore segment of the fracture can begin to fill with proppant, thus reducing the open width available for further movement of the fluid. Essentially, accumulation of proppant near the wellbore reduces the fracture width available for fluid flow which then results in higher frictional pressure losses inside the fracture, further skewing the pressure distribution, and eventually screen-out.
Field Pilots of Microbial Flooding in High-Temperature and High-Salt Reservoirs
Authors: Zhao H. , Li Z. , Zhao P. , Wu Y. 
Published: January 2008

Abstract
This paper describes the laboratory tests, including bacteria screening, bacteria culturing and nutrient solution screening for microbial flooding in water injection wells in High Temperature and High Salt Reservoirs(HTHS) reservoirs with temperature of 85°C and salinity of 12×104mg/l in Wenmingzhai Oilfield. The microbes and their nutrient solutions have been cultured through directed domestication of bacteria in injected water, microbe adaptability evaluation and simulation tests of oil flooding in cores. The well selection principles, injection occasions in field tests and the injection process are presented. The technology were successfully applied in 12 wells and result show that microbial flooding resulted in stable wellbore pressure and better water injection profile. Water cut was reduced and oil production rate was increased in corresponding oil wells,. Total oil increasment was 9536 tons. The microbial mother solution with 1×108 microbes per ml obtained 53t oil increasment, with a benefit and investment ratio of 1: 5.5. Therefore, this microbial flooding process is of great economic benefit and good application prospect.
Understanding Reservoir Performance and Uncertainty Using a Multiple History Matching Process
Authors: Bustamante D. S. , Keller D. R. , Monson G. D. 
Published: January 2008

Abstract
This paper describes the history matching and predictive case studies of two deepwater Gulf of Mexico (GOM) fields using an advanced Bayes linear estimation tool. Advantages of the tool include significant acceleration of the history matching process, identification and quality measurements of multiple history matches, quantification of reservoir uncertainty, and an improved understanding of reservoir performance. Additionally, a statistical estimator of predictive simulation results is created to generate statistically valid confidence intervals around performance predictions. This paper describes a practical workflow incorporating this tool to rapidly evaluate deepwater producing gas fields, and illustrates its use to determine remaining field potential and future development requirements of two fields, the Harrier and the Raptor Fields in the Pioneer Natural Resources-operated Falcon Corridor.
Efficient Design of Reservoir Simulation Studies for Development and Optimization
Authors: Kalla Subhash , White Christopher D. 
Published: January 2008

SummaryDevelopment studies examine geologic, engineering, and economic factors to formulate and optimize production plans. If there are many factors, these studies are prohibitively expensive unless simulation runs are chosen efficiently.Experimental design and response models improve study efficiency and have been widely applied in reservoir engineering. To approximate nonlinear oil and gas reservoir responses, designs must consider factors at more than two levels—not just high and low values. However, multilevel designs require many simulations, especially if many factors are being considered. Partial factorial and mixed designs are more efficient than full factorials, but multilevel partial factorial designs are difficult to formulate. Alternatively, orthogonal arrays (OAs) and nearly-orthogonal arrays (NOAs) provide the required design properties and can handle many factors. These designs span the factor space with fewer runs, can be manipulated easily, and are appropriate for computer experiments.The proposed methods were used to model a gas well with water coning. Eleven geologic factors were varied while optimizing three engineering factors. An NOA was specified with three levels for eight factors and four levels for the remaining six factors. The proposed design required 36 simulations compared to 26,873,856 runs for a full factorial design. Kriged response surfaces are compared to polynomial regression surfaces. Polynomial-response models are used to optimize completion length, tubinghead pressure, and tubing diameter for a partially penetrating well in a gas reservoir with uncertain properties.OAs, Hammersley sequences (HSs), and response models offer a flexible, efficient framework for reservoir simulation studies.
Wettability Alteration to Intermediate Gas-Wetting in Gas-Condensate Reservoirs at High Temperatures
Authors: Fahes Mashhad , Firoozabadi Abbas 
Published: January 2008

Summary
Wettability of two types of sandstone cores, Berea (permeability on the order of 600 md), and a reservoir rock (permeability on the order of 10 md), is altered from liquid-wetting to intermediate gas-wetting at a high temperature of 140°C. Previous work on wettability alteration to intermediate gas-wetting has been limited to 90°C. In this work, chemicals previously used at 90°C for wettability alteration are found to be ineffective at 140°C. New chemicals are used that alter wettability at high temperatures. The results show that: (1) wettability could be permanently altered from liquid-wetting to intermediate gas-wetting at high reservoir temperatures, (2) wettability alteration has a substantial effect on increasing liquid mobility at reservoir conditions, (3) wettability alteration results in improved gas productivity, and (4) wettability alteration does not have a measurable effect on the absolute permeability of the rock for some chemicals. We also find the reservoir rock, unlike Berea, is not strongly water-wet in the gas/water/ rock system.
Implementation of Tree Cutting Best Practice Based on Reduced Impact Logging Guidelines for Indonesia on Tangguh LNG Project
Authors: Narwoko Narwoko 
Published: January 2008

Abstract
For years forestry practice has not been conducted wisely per applicable regulation and standard which in turn create significant long term impact to the surrounding forestry areas as well as disturb the long term sustainable growth of the forest that finally impacted the community life and biodiversity of the area.
Tangguh LNG Facilities is located in production forest on Bintuni Bay Regency, Papua, Indonesia. Total land purchased by project is 3266ha. Construction of the facilities requires the clearing of some 800 ha production forest and the remaining area of about 2400 ha will be maintained as buffer zone area. Perimeter fence will be developed to protect the buffer zone area. Construction of the facilities in such area with rich biodiversity is a challenging effort particularly to minimize the impacts to the surrounding forests in compliance with the Indonesian and international regulation and standards, and to ensure the biodiversity protection and environmental protection of the forest area.
To achieve the objectives, Tangguh LNG Project develops and implements the tree cutting and land clearing plan to comply with the Indonesia applicable regulations and International best practice including the implementation of Reduced Impact Logging Guidelines for Indonesia. The plan developed by forestry experts and implemented with full supervision from project team. A number of compliance checklists have been developed to ease the implementation of the plan which also helps to track any deviation of the implementation to the said plan.
With the implementation of such plan up to the current stage of the project, minimization of impact to the surrounding area could be achieved and it is expected that in overall the project activities and the operation of the facilities could minimize the negative impact and maximize its positive impact to the area. This will harmonize the existence of the facilities with the surrounding environment so Industrial facilities are not perceived anymore as the major source of environmental impact.
Petrophysical Type Curves for Identifying the Electrical Character of Petroleum Reservoirs
Authors: Worthington Paul F. 
Published: January 2008

Summary
A user-friendly type chart has been constructed as an aid to the evaluation of water saturation from well logs. It provides a basis for the inter-reservoir comparison of electrical character in terms of adherence to, or departures from, Archie conditions in the presence of significant shaliness and/or low formation-water salinity. Therefore, it constitutes an analog facility. The deliverables include reservoir classification to guide well-log analysis, a protocol for optimizing the acquisition of special core data in support of log analysis, and reservoir characterization in terms of an (analog) porosity exponent and saturation exponent.
The type chart describes a continuum of electrical behavior for both water and hydrocarbon zones. This is important because some reservoir rocks can conform to Archie conditions in the fully water-saturated state, but show pronounced departures from Archie conditions in the partially water-saturated state. In this respect, the chart is an extension of earlier approaches that were restricted to the water zone. This extension is achieved by adopting a generalized geometric factor—the ratio of water conductivity to formation conductivity—regardless of the degree of hydrocarbon saturation. The type chart relates a normalized form of this geometric factor to formation-water conductivity, a "shale" conductivity term, and (irreducible) water saturation. The chart has been validated using core data from comprehensively studied reservoirs.
A workflow details the application of the type chart to core and/or log data. The analog role of the chart is illustrated for reservoir units that show different levels of non-Archie effects. The application of the method should take rock types, scale effects, the degree of core sampling, and net reservoir criteria into account. The principal benefit is a reduced uncertainty in the choice of a procedure for the petrophysical evaluation of water saturation, especially at an early stage in the appraisal/development process, when adequate characterizing data may not be available.
Application of Gas Lift to Heavy-Oil Reservoir in Intercampo Oilfield, Venezuela
Authors: Hong'en D. , Yuwen C. , Dandan H. , Wenxin C. , Guozhen Z. 
Published: January 2008

Abstract
This paper presents successful applications of the gas lift to heavy oil reservoirs in Intercampo oilfield, Lake Maracaibo. Liquid production rate ranges from 50 to 2000 bbl per day per well, gas lift was selected as the first artificial lift method in the oilfield. The paper expresses the gas lift mechanisms in high water cut with lower API degree in heavy oil reservoirs. The theory analysis showed that injection gas rate of gas lift and GOR of oil well have direct effects on fluid flow state in wellbore.
Scenarios of theory design and actual production of gas lift were described in the paper. For artificial lift design, the paper points out the correlation equations of gas lift for heavy crude reservoirs that their flow behavior of actual situation should not characterized by present equations, therefore, there are big error value between theory design and actual production when producer is high water cut with lower API degree. In addition, the error created reason was analyzed and oil well normal production in high water cut stages with lower API degree was emphasized, in the case, emulsion of water and oil should not happen.
A corrected coefficient of gas lift design was provided under the high water cut with lower API degree. Nowadays, for the new correlations are very preliminary that will need to be developed by means of production engineers and researchers further. It is particularly important to production engineers in optimization and design of gas lifting equipments.
Is It Possible To Treat Produced Water for Recycle and Beneficial Reuse?
Authors: Hum F. , Tsang P. , Kantzas A. , Harding T. 
Published: January 2008

Abstract
Fresh water scarcity and increasing demand are worldwide concerns and are being addressed by a number of water management initiatives in Alberta and Canada. In 2003, 0.3 billion m3 of produced water was injected into disposal wells associated with oil and gas production in Alberta. This volume of water is a potential resource for recycling and beneficial reuse in Alberta, which would have a significant impact on sustainable development in Alberta. This water must first be treated to meet water quality requirements and regulatory guidelines for specific applications. This paper provides a comprehensive technical and economic review of water treatment technologies and shows that water treatment processes are commercially available. Although the cost of implementing suitable treating processes to meet drinking water quality guideline is estimated at three times the current cost of municipal water supply in Alberta, it is more feasible to recycle produced water for other purposes, such as agricultural or petroleum application (i.e., waterflooding, etc.). This is because water quality guidelines for most other applications are not as stringent as that for drinking water and there is increasing public resistance for industry to use fresh water for commercial applications. A multi-disciplinary research and development team studying water recycle and beneficial reuse is necessary to look into these issues. The University of Calgary is set to collaborate on such projects due to the current research emphasis on sustainable energy and environmental impact. Collaboration between the government, industry and academia to develop initiatives aimed at reducing fresh water is possible in Calgary for several reasons. One is the proximity of many major oil and gas companies in this city, which would allow for easy communication. Another is the fact that the current price of oil would not inhibit producing companies from investing in this kind of research. The result can be well-developed initiatives to treat and recycle produced water for beneficial reuse, thus reducing fresh water demand for many applications in the petroleum and agricultural industries.
Recovery Performance and Economics of Steam/Propane Hybrid Process
Authors: Deng X. 
Published: January 2008

Abstract
In this study, a particular hybrid process with propane and steam co-injected is simulated numerically under different operation strategies. The roles of propane in the hybrid process are investigated. The economics of these hybrid processes are also evaluated with a supply cost model. Results show that hybrid processes with steam and propane co-injection can have the same supply cost as that of SAGD process and propane-related cost is a small part of the total supply cost in these hybrid processes due to the small amount of propane used in this study. Results also show that low pressure hybrid processes are more cost-efficient than their high pressure counterparts.
ITM Oxygen for Gasification
Authors: Armstrong P. A. , Foster E. P. , Gunardson H. H. 
Published: January 2008

Abstract
An Air Products-led team is developing a new air separation technology - Ion Transport Membrane Oxygen - based on ceramic membranes that selectively transport oxygen ions when operated at high temperature. Under the influence of an oxygen partial-pressure driving force, the ITM Oxygen process achieves a high-purity, high-flux separation of oxygen from air. By integrating the energy-rich, vitiated, non-permeate stream with a gas turbine system, the overall process co-produces high-purity oxygen, power, and steam if desired. As a result, the technology is ideally suited for advanced energy conversion processes such as IGCC that require oxygen and use heavy carbonaceous feedstocks (resid oils, bitumens, coke, coal), as well as for traditional industrial applications for oxygen and distributed power.
During Phases I and II of a three-phase development program with the U.S. Department of Energy, the ITM Oxygen team established the feasibility of the ceramic membrane approach and designed and built commercial-scale membrane modules. A prototype facility that will produce 5 tons-per-day of oxygen will start up this year. Larger-scale test rigs are planned, with commercialization projected in the latter part of the decade.
This paper will present an overview and status of the ITM Oxygen development effort, and the integration into gasification and clean energy processes. Process integration options will be discussed and contrasted. The economic benefits compared to the best commercial air separation alternative will be highlighted.
Improved Steamflood Analytical Model
Authors: Chandra S. , Mamora D. D. 
Published: January 2008

Summary
The Jones (1981) steamflood model incorporates oil displacement by steam as described by Myhill and Stegemeier (1978), and a three-component capture factor based on empirical correlations. The main drawback of the model, however, is the unsatisfactory prediction of the oil production peak: It is usually significantly lower than the observed value. Our study focuses on improving this aspect of the Jones model.
In our study, we simulated the production performance of a five-spot-steamflood-pattern unit and compared the results against those based on the Jones model (1981). To obtain a satisfactory match between simulation and Jones-analytical-model results, at the start and height of the production peak, the following refinements to the Jones model were necessary. First, the dimensionless steam-zone size AcD was modified to account for the decrease in oil viscosity during steamflood and its dependence on the steam injection rate. Second, the dimensionless volume of displaced oil produced VoD was modified from its square-root format to an exponential form. The modified model gave very satisfactory results for production performance for up to 20 years of simulated steamflood, compared to the original Jones model. Engineers will find the modified model an improved and useful tool for the prediction of steamflood-production performance.
Fiber-Optic Distributed-Temperature-Sensing Technology Used for Reservoir Monitoring in an Indonesia Steamflood
Authors: Nath D. K. , Sugianto R. , Finley D. 
Published: January 2008

Abstract
The world's largest steam-flood operation is conducted on the island of Sumatra in Indonesia. Fiber-optic Distributed Temperature Sensing (DTS) surveys are used in the Sumatra fields to provide valuable data for reservoir management. The DTS profile data can determine the temperature and extent of a steam chest as well as the temperature gradient for either over-burden- or under-burden reservoirs. This information is vital for properly setting steam-injection target rates. The information is also used to mitigate steam breakthroughs and eruptions as well as to identify bypass oil.
Steam flood operations experience many types of problems: i.e., inefficient injection rates, wasted heat to the casing, sanding in producers, liner failures, pump failures as wells as the need to improve the efficiencies of the vapor collection systems, well-test stations, and central gathering stations. Based on these challenging problems, periodic wellbore temperature surveys are required in order to improve heat management and ultimately improve profitability. Conventional temperature logs cannot be run in these wells without first pulling the pumps from the completion. Therefore, employing a fiber-optic DTS system that would be attached to the production tubing was suggested.
This paper will present case histories of successful applications of fiber-optic DTS surveys that improved steam- flood management in this steam- flood field in Indonesia.
The benefits from the fiber-optic DTS monitoring were: Significant improvement in the understanding of steam breakthrough zones along the pay zone interval of production wellsImproved understanding of the steam path in steam-injector wellsImprovement in the real-time temperature profile in observation wells to identify steam-zone development and unswept or bypassed oil zones in the steam flood patterns.