|2000年08月-2001年08月||テキサス大学オースティン校 その他 石油工学科|
|1995年04月-1999年03月||早稲田大学 工学部 環境資源工学科|
学士 課程 早稲田大学 地球・資源システム工学
修士 課程 テキサス大学オースティン校 地球・資源システム工学
Doctor of Philosophy 課程 テキサス大学オースティン校 地球・資源システム工学
|2004年03月-2004年08月||テキサス大学オースティン校Petroleum EngineeringPostdoctoral Research Scientist|
|2004年08月-2006年08月||ベーカーオイルツールCased Hole Completion SystemApplications Engineer|
|2006年08月-2014年08月||コノコフィリップスGlobal Completion EngineeringStaff Completion Engineer|
|2012年08月-2014年08月||ConocoPhillips NorwayWell OperationCompletion Geoemchanics Engineer|
|2014年08月-2015年03月||コノコフィリップスGlobal Completion EngineeringStaff Completion Engineer|
Society of Petroleum Engineers
|2010年04月-2010年10月||Society of Petroleum EngineerProgram Subcommittee for SPE ATCE (Production Monitoring and Control)|
2012年10月授与機関：Society of Petroleum Engineers - Gulf Coast Section
2013年10月授与機関：Society of Petroleum Engineers
2009年09月授与機関：Society of Petroleum Engineers
工学 / 地球惑星科学 / 地球・資源システム工学
Papamichos, E. and Furui, K.
ARMA 13-304 presented at the 47th US Rock Mechanics /Geomechanics Symposium held in San Francisco, CA, 23 – 26 June2013年-
概要：The paper investigates the capability of a simplified Mohr-Coulomb (MC) analytical model to predict satisfactorily fully anisotropic loading experimental results on hole failure, as well as numerical predictions from several parametric analyses of field cases based on a 3D non-linear FEM borehole and perforation failure analysis model (Sand3D), which employs the critical plastic strain failure criterion coupled with a Drucker-Prager failure surface. The comparisons with the experimental data and the field simulations demonstrate that the MC model is insufficient for satisfactory predictions under anisotropic loadings. A Drucker-Prager type model is advanced and shows significantly improved analytical predictions under any loading condition. Two field case comparison examples show that the developed analytical sand production initiation model accounts for the effect of intermediate stress and gives good matches to the formation failure envelopes predicted by the numerical model.
Fuh, G.-F., Morita, N., and Furui, K.
Paper SPE 124388 presented at the SPE Annual Technical Conference held in New Orleans, LA, 4-7 Oct2009年-
概要：The manufacturer's specifications of sand screen usually provide information such as base pipe collapse pressure, maximum tensile load, and bending strength. However, the problem is that a very heavy base pipe is thus required to satisfy such specifications if the pipe collapse pressure indicated by manufacturer is used for field application. The reason is that the screen collapse tests are conducted under hydrostatic loading for screens wrapped with rubber jacket by screen manufacturers. Observation of these tests shows that screen collapse occurs immediately after the base pipe starts yielding. However, this is not the case if screens are installed in the wellbore under geotectonic load. A series of laboratory tests are conducted using either straight pipes without screen or pipes with screen installed in a drilled borehole of some large rock sample. Since the base pipe failure is the dominant factor for screen failure, half of the experiments shown in this paper used straight pipe without including screen or shroud. These tests show that tubular strings may initiate yielding earlier than the specified yielding data provided by screen manufacturers. However, after the initial yielding, the base pipe deforms gradually and it never collapses even after exceeding the ordinary base pipe yielding (0.2-0.4% deformational strain) by more than 10 times. Based on these laboratory tests, a numerical model is constructed for screen design along with gravel pack or stand-alone screen in openhole completions. The numerical model first simulates hydrostatic screen collapse tests conducted by manufacturers to confirm the design specifications as measured. Then, it is extended to simulate screen behavior after it is installed downhole. It assumes that a screen is placed in the borehole, and then gravel-pack covers the screen, followed by reservoir depletion and drawdown in production mode. This paper sheds light on the sand screen collapse resistance under three typical loading types: hydrostatic, geotechtonic load without void around sand screen and geotectonic load with void for openhole standalone screen applications. Distinctly different failures criteria are proposed for these three types of loadings. Empirical data under such high stress levels are rarely found in the literatures.
Achnivu, O.I., Zhu, D., and Furui, K.
Paper SPE 115753 presented at the SPE Annual Technical Conference held in Denver, CO, 21-24 Sep2008年09月-
概要：Accurate and reliable downhole data acquisition has been made possible by advanced permanent monitoring systems such as downhole pressure and temperature gauges and fiber optic sensors. These downhole measurement instruments are increasingly incorporated as part of the intelligent completion in complex (highly slanted, horizontal, and multilateral) wells where they provide bottomhole temperature, pressure and sometimes volumetric flow rate along the wellbore. To fully realize the value of these intelligent completions, there is a need for a systematic data analysis process to improve our understanding of reservoir and production conditions using the acquired data and to make decisions for well performance optimization. We have successfully developed a model to predict well flowing pressure and temperature (i.e. the forward model), and applied inversion method to detect water and gas entry into wellbore using the synthetic data generated by the forward model (i.e. the inversion model) in the previous study. It is concluded that temperature profiles could provide sufficient information to identify fluid entries, especially in gas wells. However, both the mathematical complexity and advanced well structure lead to challenges in model validation and application. In this study, we applied the wellbore-reservoir flow coupled thermal simulation model to high-rate gas wells with field data. The main objectives are to evaluate applicability of the model to field problems, to study the sensitivity of parameters such as permeability and reservoir pressure on accuracy of interpretation, and to generate practical guidelines on how to initialize the inversion process. The model is applied to highly-slanted gas wells with water produced from a bottom aquifer. The interpretation result was compared against production logging data. The sensitivity of interpretation error to input reservoir properties are examined and the results showed that temperature and pressure anomalies caused by water production and flow rate changes can be detected theoretically and also practically. Judgments should be used based on the understanding of temperature and pressure behavior when initializing the forward model and this can increase efficiency of model application. The study results and guidelines developed in this study will help us to design permanent monitoring systems and set realistic expectation for predictive capability of intelligent well systems.
Mishra, V., Zhu, D., Hill, A.D., and Furui, K.
Paper SPE 107780 presented at the SPE European Formation Damage Conference held in Schveningen, The Netherlands, 30 May – 1 June2007年05月-
概要：In several places around the world, notably the North Sea and the Middle East, carbonate reservoirs are being accessed with very long horizontal wells (2000 to 20,000 feet of reservoir section.) These wells are often acid stimulated to remove drilling fluid filter cakes and to overcome formation damage effects, or to create acid fractures or deep matrix stimulation to enhance productivity. Good acid coverage with a relatively small acid volume is required to economically obtain the desired broad reservoir access. We have developed a model to predict the placement of injected acid in a long horizontal well, and to predict the subsequent effect of the acid in creating wormholes, overcoming damage effects, and stimulating productivity. The model tracks the interface between the acid and the completion fluid in the wellbore, models transient flow in the reservoir during acid injection, considers frictional effects in the tubulars, and predicts the depth of penetration of acid as a function of the acid volume and injection rate at all locations along the completion. We have used this model to simulate treatments that are typical of those performed in the North Sea and in the Middle East. We present a hypothetical example of acid placement in a long horizontal section and an example of using the model to history match actual treatment data from a North Sea chalk well.
Zhu, D. and Furui, K.
Paper SPE 102104 presented at the SPE ATCE held in San Antonio, TX, 24-27 Sep2006年-
Sakowski, S.A., Anderson, A., and Furui, K.
Paper SPE 94672 presented at the SPE Hydrocarbon Economics and Evaluation Symposium held in Dallas, Tx, 03-05 Apr2005年-
概要：Intelligent well technology, referring to the implementation of fundamental process control downhole, has advanced rapidly over the last decade in the upstream oil and gas industry. Application of this technology has continued to expand since recent installation results have demonstrated the value of these completions with a high success rate that operators find attractive. In this paper, we present an economic evaluation procedure to quantify the benefit of Intelligent Well Systems based on net present value (NPV) calculations. Reducing well count and eliminating or reducing interventions by using Intelligent Well Systems has the potential to add many millions of dollars to well NPV, since drilling rig and workover costs may be very expensive, especially in offshore deepwater environments. Delayed revenue associated with production shut-in also must be considered and reduced by discount rate at the same time that intervention and well operating costs increase by inflation rate. The use of Intelligent Well Systems not only reduces or eliminates some capital and operating costs, but also allows operators to accelerate oil production, increase the ultimate recovery and reduce water handling cost, which result in significant benefits in NPV of a project. Thus, Intelligent Well Systems are becoming economically attractive for modest-cost onshore operations as well as for the high-cost offshore environments for which they were initially deemed applicable.
Vachon, G. and Furui, K.
Paper SPE 93621 presented at the SPE Middle East Oil and Gas Show and Conference, 12-15 Mar2005年-
概要：Accelerated production, increased ultimate recovery, and reduced interventions are goals of any operating company. It is now possible to attain all of these goals simultaneously by retrofitting intelligent well technology to an existing, conventional completion. This task is much more complex when the new technology must be installed in conjunction with artificial lift, such as an electric submersible pump (ESP). However, new technology and procedures have overcome this complexity and offer a viable option for optimizing production in existing completions that use artificial lift. Commingled or selective production from two or more zones is an ideal method of accelerating production from a single well. Traditional designs require interventions into the well to select the intervals to be produced. In most ESP wells, commingling is achieved by using "Y" blocks which allow production tubing to be run from the tubing hanger to the zones of interest. The ESP must then be downsized to accommodate this side-string, which significantly reduces available pump horsepower. This paper focuses on single-ESP wells producing from multiple pay zones. Various application patterns for use of intelligent well technology beneath ESPs are presented, especially focusing on immediate and future benefits. Theoretical examples are presented to illustrate how intelligent completions can enhance the ESP performance, add flexibility, and extend the range of application for a given pump.
Furui, K., Zhu, D., and Hill, A.D.
Paper SPE 90433 presented at the 2004 SPE ATCE held in Houston2004年09月-
概要：Gravel packing is widely used in well completions to prevent sand production. An efficient gravel pack completion retains formation sand without creating significant additional pressure drop through the completion itself. To predict gravel-packed well performance, a completion model that calculates pressure drop for a gravel pack completion is necessary. In this paper, a theoretical turbulence skin factor model for cased-hole gravel-packed wells is presented that can be used to determine the effects of the gravel pack on well performance. The overall pressure drop through the gravel pack completion is divided into three parts; the pressure drop through the gravel between the casing and the screen, which is usually small and can be neglected; the pressure drop occurring through gravel in the perforation tunnels penetrating through the casing and cement and out into the formation; and the pressure drop outside the casing caused by flow converging to the perforations. This study is focused on the latter two pressure drops. Based on extensive 3D finite element simulation studies, the flow field in and around a gravel pack completion is approximated by a series of linear, radial, and hemispherical flow geometries, and the Forchheimer equation is then integrated along a simplified flowpath to obtain the pressure drop both inside and outside of the casing. The FEM simulation results show that the flow geometry of a cased, perforated, and gravel packed well greatly depends on the ratio of the formation permeability to the permeability of the gravel in the perforation tunnels. As the perforation tunnel permeability approaches the formation permeability, the flow geometry near the perforation through the casing is no longer linear but spherical as if there is no perforation in the formation. As a result, the conventional model of flow in the gravel packed perforations may give inaccurate results under these conditions. The new skin factor model accounts for the transition from linear to spherical flow as a function of the ratio of the formation to perforation tunnel permeabilities. This model also includes permeability damage in a perforation tunnel that significantly increases rate dependent (turbulent) skin effects. We used the model to determine the gravel pack conditions needed to insure that gravel pack skin factor is low and to minimize the effects of turbulence in the gravel pack in high rate wells. Guidelines for gravel permeability are presented based on these results.
Kent, A.W., Burkhead, D.W., Burton, R.C., Furui, K., Actis, S.C., Bjornen, K., Constantine, J.J., Gilbert, W.W., Hodge, R.M., Ledlow, L.B., Nozaki, M., Vasshus, A., and Zhang, T.
SPE Drilling & Completion査読有り29(2)p.165 - 1812014年06月-
概要：This paper describes the design, testing, installation, and performance of the first fully completed well by use of an intelligent inner completion inside an uncemented liner with openhole packers for zonal isolation. The well-design concept evolved from technical challenges associated with completing long cased-and-cemented laterals in the mature Ekofisk waterflood. The term fully completed implies full reservoir access along the pay length for production and high-rate matrix acid stimulation by use of limited entry for fluid diversion within well segments. The paper covers the development and qualification of customopenhole 7 5/8-in.-liner components that can handle high differential pressures and severe temperature fluctuations of 200°F; the marriage of this complex liner with a five-zone intelligent-completion system; and results from 1 year of system-integration testing. The paper also discusses the strategic placement of both mechanical openhole and inner-string packers based on caliper and drilling logs; challenges met and overcome during installation; and comprehensive downhole-gauge data that confirms the performance of each component before, during, and after the stimulation. The Ekofisk field waterflood began in 1987 and continues to date, exceeding expectations for improved oil recovery while mitigating reservoir compaction. As the waterflood matures, new wells are more often found partially water-swept. Limited infrastructure for lifting and handling the high water production has led to increased emphasis on isolating these water-swept intervals. Cased, cemented, and perforated completions have traditionally been used for this service. Effective placement of cement is challenging in horizontals 4,000–8,000 ft in length, where rotation of the liner is not possible and high effective-circulating densities limit rates during cementing. Wide variations in reservoir pore pressures, often in excess of 2,000-psi difference along the lateral, are typical of the Ekofisk chalk and compound the difficulties of cementing. As a result, a new method for zonal isolation has been developed to ensure the success of future infill-drilling campaigns. The design and careful planning that went into the fully completed openhole uncemented-liner strategy resulted in a successful field trial and has proved this solution to be an effective alternative to cemented reservoir liners in long horizontals where zonal isolation is critical. Use of the intelligent-well system (IWS) allowed offline acid stimulation without rig, coiled-tubing, or wireline intervention. What would have traditionally been a significant water producer, with three water-swept zones totaling nearly 2,000 ft across a 4,000-ft reservoir section, has turned out to beone of the best oil producers in the field, with nearly zero watercut. Production results show high productivity with highly negative acidized-completion skins.With large investments in intelligent completions to provide zone-specific inflow control and water shutoff, isolation outside the liner becomes much more important. Over recent years, the Ekofisk wells have illustrated the difficulty of achieving effective cement along lengthy reservoir targets. The openhole fully completed solution combining an accessorized uncemented liner with an inner intelligent-completion string will allow operators to push the limits in terms of lateral length while maintaining full control over producing and nonproducing zones.
Furui, K., Fuh, G.-F., and Morita, N.
SPE Drilling & Completion査読有り27(2)p.241 - 2522012年-
概要：Many casing- and screen-damage incidents have been reported in deepwater oil and gas fields in the Gulf of Mexico and other locations around the world. We reviewed historical casing/well failure events in a highly compacting sandstone field and performed a comprehensive geomechanics analysis of various casing- damage mechanisms (tension, axial compression, shear, and bending) related to large reservoir depletion. Among five wells that experienced mechanical well-integrity issues, two of them showed casing restrictions in the caprock at intervals approximately 1,000- to 1,600-ft true vertical depth (TVD) above the top of the depleting (main) reservoir. A multi-finger caliper log obtained from one of the wells indicates that the overburden casing failure occurred at a highly geopressured, thin sand layer approximately 1,100-ft TVD above the top of the compacting reservoir. The remaining casing-failure events occurred near (less than 200-ft TVD) or within the compacting reservoir interval. A 3D nonlinear finite-element-method (FEM) model has been developed for simulating stress changes in the overburden and the reservoir intervals and evaluating the effect of lithological anomalies on casing stability. The simulation results indicate that large tensile and shear strains could develop within a thin, weak-strength layer in the overburden and at the interface between caprock and the depleting reservoir interval. Casing damage by bending/shear could also occur at these thin-layered sands saturated with overpressured gas. In the reservoir interval, shear stresses acting on the screens can be relatively high because of the difference of the movements between the internal base pipe and the external shroud and gravel. Screen failure may also occur at the welded points. If casing failure occurs in the unperforated sand layer just above the compacting reservoir, it induces localized high-velocity flow on the upper part of the screen, causing potential screen erosion. Casing failure caused by fault slip near the reservoir occurs only if a fault has sealing capability while maintaining a large pressure differential across the fault plane. The numerical-analysis results presented in this work help engineers understand possible casing- and screen- deformation and -failure mechanisms experienced in highly compacting sandstone fields. On the basis of the study findings, we also present some completion-design guidelines to avoid or mitigate compaction-induced casing damage in both the overburden and reservoir intervals.
Furui, K., Burton, R.C., Burkhead, D.W., Abdelmalek, N.A., Hill, A.D., Zhu, D., and Nozaki, M.
SPE Journal査読有り17(1)p.280 - 2912012年03月-
概要：Successful acid stimulation of long-horizontal-well intervals in carbonate reservoirs requires effective acid distribution along the entire reservoir length. Such treatments also require large volumes of acid and seawater/brine injection at sufficiently high injection rates to drive the acid wormholes deep into the reservoir. Under these flowing conditions, significantly large tubing friction loss is anticipated unless optimal friction reducer performance in the tubing is maintained throughout the pumping operation. Because prediction of wormhole penetration and corresponding skin factor depends on analysis of downhole-injection pressures at the reservoir face, it is crucial to properly account for these hydrostatic and friction changes prior to evaluation of wormhole length and skin factor. In this study, an integrated flow model has been developed to predict the wellbore-pressure profile and wormhole distribution by tracking the movement of the acid in the wellbore and the formation. The wellbore-flow model is based on steady-state, 1D, pressure-based nodal method. The segmented wellbore in the reservoir interval is then coupled with analytical transient reservoir-flow models. The wormhole propagation in the formation is calculated based on the modified Buijse-Glasbergen correlation and upscaling model developed in our earlier work. The resultant wormholing skin factor is calculated by simulating and updating the changing well injectivity along the entire injection interval at every timestep. The model developed in this work is applicable for both fully completed wells (i.e., radial flow) and selectively completed perforation-cluster wells (i.e., spherical flow) typically employed in carbonate reservoirs. Analysis of injection rates and pressures during acid treatment provides engineers with a way to determine the varying injectivity and tubing friction as stimulation proceeds. The model presented here can be used as a forward model for analyzing real-time treatment rate and pressure histories and can also be used to review past treatments to improve future treatment designs. Using actual field-stimulation data, we also discuss key elements to successful stimulation planning and the diagnosis of matrix-acid treatments to achieve effective wormhole coverage for horizontal completions in carbonate formations.
Furui, K., Burton, R.C., Burkhead, D.W., Abdelmalek, N.A., Hill, A.D., Zhu, D., and Nozaki, M.
SPE Journal査読有り17(1)p.280 - 2912012年03月-
Furui, K., Fuh, G.-F., Abdelmalek, N., and Morita, N.
SPE Drilling & Completion査読有り25(4)p.530 - 5432010年10月-
概要：Numerous casing and production-liner deformation/failure problems have been reported in high-porosity chalk formations in both the overburden and the reservoir sections, causing costly operation problems that prevent workovers and recompletions. This paper presents the results of studies performed to investigate stability of an openhole, cemented liner and uncemented-liner completions in a highly compacting chalk formation. The effects of critical cavity dimensions caused by various acid-stimulation techniques were also investigated. On the basis of the review of historical caliper-survey data, we ascertain that axial-compression collapse is a major liner-deformation mechanism in the reservoir zones. Axial-compression collapse has been found in both low-angle wells (also in buildup sections of horizontal wells) and horizontal laterals. The casing deformation in low-angle sections is a result of reservoir compaction (i.e., change in the vertical formation strain), while the deformation in horizontal sections is primarily induced by increased axial loading because of cavity deformation. The current completion practice using cluster perforations and high-volume acid treatments causes vertically enlarged cavities, resulting in poor radial constraint. A series of laboratory triaxial tests was performed on selected reservoir chalk samples to measure the stress/strain and failure behavior of the chalk formation considering a wide range of porosity and water saturation and different levels of confining pressures. Using the chalk-failure criteria and constitutive relations developed from the analysis of laboratory triaxial-compression-test data, a 3D nonlinear poroelastic/plastic finite-element-method (FEM) model was developed for the openhole stability analysis. The simulation results show that the abnormally high ductility of chalks after pore collapse around a borehole could actually enhance borehole stability, with a magnitude beyond expectation. In this study, analytical and numerical models are also developed for evaluating cavity-induced axial- compression collapse of production liners. Model results indicate that the risk of the cavity-induced axial- compression collapse substantially increases for short perforated intervals stimulated with large acid treatments. However, increasing the perforation-interval lengths along the entire liner axis results in more-uniform acid distribution and will greatly reduce the chance of axial-compression collapse caused by localized cavity deformation. On the basis of these analysis results, key completion design criteria and stimulation strategies were developed for wells completed in highly compacting chalk reservoirs to reduce risk of casing and liner mechanical problems.
Furui, K., Zhu, D., and Hill, A.D.
SPE Drilling & Completion査読有り23(3)p.205 - 2152008年09月-
概要：Using a combination of analytical calculations and 3D finite-element simulation, we have developed a comprehensive skin-factor model for perforated horizontal wells. In this paper, we present the mathematical model development and validation by comparison with finite-element simulation results. With the new perforation skin model, we then show how to optimize horizontal well perforating to maximize well productivity. A cased, perforated well may have lower productivity (as characterized by a positive skin factor) relative to the equivalent openhole completion because of two factors: the convergence of the flow to the perforations, and the blockage of the flow by the wellbore itself. Because of the orientation of a horizontal well relative to the anisotropic permeability field, perforation skin models for vertical wells that consider these effects, notably the Karakas and Tariq model (1991), are not directly applicable to perforated horizontal completions. Using appropriate variable transformations, we derived a skin-factor model for a horizontal perforated completion that is analogous to the Karakas and Tariq (1991) vertical-well model. The empirical parameters in the model were determined from an extensive 3D finite-element simulation study. The results of the new model show that the azimuth of a perforation (the angle between the perforation tunnel and the maximum permeability direction, usually thought to be in the horizontal direction) affects the performance of perforated completions in anisotropic reservoirs. When perforations are normal to the maximum-permeability direction, perforations will enhance horizontal-well flow compared with an openhole completion (a negative skin factor). But if perforations are in the same direction as the maximum permeability, significant positive skin will result. The new skin-factor model provides a clear guide to the shot density, perforation orientation, and level of perforation damage that is tolerable to create high-productivity perforated completions in horizontal wells.
Furui, K., Zhu, D., Hill, A.D., Davis, E.R., and Buck, B.R.
SPE Production & Operations査読有り22(2)p.248 - 2532007年05月-
概要：A well completion is a critical interface between the productive formation and the wellbore. An effective completion must maintain the mechanical integrity of the borehole without creating any significant restrictions on the flow capacity of the well. In this paper, a process is outlined to design optimal completions for horizontal wells by applying comprehensive skin-factor models that include damage and turbulence effects for all common types of completions. Slotted or perforated liner, cased, perforated, or gravel-pack completions have been used in horizontal wells for borehole stability and sand-control purposes. However, these completions may have lower productivity (as characterized by a positive skin) relative to an equivalent openhole completion, because the convergent flow to perforations or slots increases fluid velocity in the near-well vicinity. In addition, any reduced permeability zones (formation damage caused by drilling, completion, or other processes) magnify the convergent flow effects and therefore may result in substantially increased skin factors. Compound effects of formation damage around the well completion, a crushed zone because of perforating, plugging of slots, and turbulent flow, as well as interactions among these effects, are included in the model. This paper illustrates how to use skin factor models to screen the available completion types for cased/perforated and slotted liner completions. This screening approach considers reservoir permeability, permeability anisotropy, fluid properties, formation damage effects, and rock mechanical characteristics as the key parameters. The types of completion that yield the most productive well performance for this matrix of properties are presented. A more detailed completion design is then illustrated by showing how the skin-factor models were used to redesign the slot configuration of liner completions for viscous oil reservoirs on the North Slope of Alaska. Application of the slotted or perforated liner models to the readily available liners showed that the completion skin factor can vary by as much as 40%, depending on the detailed characteristics of the slots or perforations in the liner (slot or perforation size, density, and distribution). The example showed that optimizing the performance of the completion can increase well productivity at little or no cost and with no loss in liner mechanical strength.
Suzuki, I., Morita, N., and Furui, K
Journal of the Japanese Association for Petroleum Technology査読有り71(3)p.253 - 2662006年-
Furui, K., Zhu, D., and Hill, A.D.
SPE Production & Facilities査読有り20(3)p.207 - 2202005年08月-
概要：Horizontal wells or laterals are completed as openhole, slotted-liner, cased and perforated, or gravel-pack completions. We have developed a comprehensive skin-factor model to predict the performance of any of these completion types and have calibrated this model with extensive finite-element simulations of flow for a horizontal-well completion. This model can be used to predict the performance of virtually any horizontal-well completion. The new completion skin-factor model accounts for the effects of formation damage, convergent flow to perforations and slots, and flow through slots, with interaction among these effects. To account for formation damage, we extended our previous rigorous model of a damaged horizontal well to include the presence of perforations within, or extending through, the damage zone. The formation damage model is also integrated with the models of slotted-liner performance to model these completions. The model of slotted- or perforated-liner performance is made on the basis of the relationship between pressure drop and flow rate for turbulent flow in these geometries. The slotted-liner model accounts for partial plugging of the slots by grains of formation minerals or precipitates (scale). Turbulence effects are a major part of the apparent skin factor for these completion types. The model shows the recommended conditions to obtain high-productivity (i.e., low skin factor) completions in horizontal wells. In particular, the interactions among damage effects and skin effects caused by perforations or slots are shown to greatly affect horizontal-well completion performance. The models developed can be applied to design optimal completions for horizontal wells or laterals.
Furui, K., Zhu, D., and Hill, A.D
SPE Production & Facilities査読有り18(3)p.151 - 1572003年-2003年08月
概要：In this paper, we present a new analytical model for formation damage skin factor and the resulting reservoir inflow, including the effect of reservoir anisotropy and damage heterogeneity. The shape of the damaged region perpendicular to the well is based on the pressure equation for an anisotropic medium and, thus, is circular near the well and elliptical far from the well. The new model can be used for various distributions of damage along the well, depending on the time of exposure during drilling and completion. The inflow equation for a damaged, parallel-piped-shape reservoir illustrates the importance of the ratio of the reservoir thickness to the drainage length perpendicular to the well on the influence of formation damage for horizontal well productivity. Our model gives a simple, analytical expression for determining this effect.
Nozaki, M., Burton, R.C., Furui, K., Zwarich, N.R.
SPE Annual Technical Conference and Exhibition, 28-30 September, Houston,2015年10月-
概要：It is common practice to complete long carbonate intervals with multi-stage stimulation treatments especially in horizontal wells. Each zone tends to be mechanically isolated using cement or openhole packers and then acid stimulated. Zonal isolation effectiveness is judged on the basis of job pressure response or post-job production logging. The recent introduction of intelligent well systems (IWS) with zone specific pressure and temperature gauges allows more effective review of zonal isolation during stimulation. This paper reviews zonal isolation results from a series of high-rate acid jobs conducted in wells equipped with zone-specific pressure and temperature gauges. 21 acid stimulation jobs from 13 different wells are reviewed to investigate the effectiveness of zonal isolation during and after treatment. Well examples presented in this paper cover several different completion types: cemented and un-cemented; intelligent well system, plug-and-perf completion and ball-activated sliding sleeve completion. The analysis revealed several different pressure and/or flow communication patterns. Field examples and analysis results presented in this work will help engineers design and optimize cemented and un-cemented wells requiring multi-stage stimulation in carbonate fields.
Furui K., Zhu D., and Hill A.D
2002 SPE Annual Technical Conference and Exhibition, 29 September-2 October, San Antonio, Texas2002年09月-2002年09月
AW Kent, DW Burkhead, RC Burton, K Furui, SC Actis, KH Bjornen, JJ Constantine, WW Gilbert, RM Hodge, LB Ledlow, M Nozaki, A Vasshus, T Zhang
SPE Annual Technical Conference and Exhibition2013年09月-2013年09月
K. Furui, R. C. Burton, D. W. Burkhead, N. A. Abdelmalek, A. D. Hill, D. Zhu, M. Nozaki
SPE Annual Technical Conference and Exhibition2010年09月-2010年09月
Furui, K., Fuh, G.-F., Abdelmalek, N. A., & Morita, N.
SPE Annual Technical Conference and Exhibition2009年10月-2009年10月
Society of Petroleum Engineers2002年-2002年
Society of Petroleum Engineers2003年-2003年
The 21st Formation Evaluation Symposium of Japan(Japan Formation Evaluation Society – A Chapter of SPWLA)招待有り2015年10月13日
SPE ATW North Sea and European Area Stimulation(SPE)招待有り2011年
SPE ATW Performance and Design of Seawater Injectors Requiring Sand Control(SPE)招待有り2011年
Seventh SIAM Conference on Mathematical and Computational Issues in the Geosciences(SIAM)招待有り2003年
|環境資源工学の展望 14前再 【前年度成績S評価者用】||創造理工学部||2019||春学期|
|Research on Geomechanics and Petroleum Production Engineering||大学院創造理工学研究科||2019||通年|
|Advanced Numerical Rock Mechanics||大学院創造理工学研究科||2019||春学期|
|Seminar on Geomechanics and Petroleum Production Engineering A||大学院創造理工学研究科||2019||春学期|
|Seminar on Geomechanics and Petroleum Production Engineering B||大学院創造理工学研究科||2019||秋学期|
|Seminar on Geomechanics and Petroleum Production Engineering C||大学院創造理工学研究科||2019||春学期|
|Seminar on Geomechanics and Petroleum Production Engineering D||大学院創造理工学研究科||2019||秋学期|
|Master's Thesis (Department of Earth Sciences,Resources and Environmental Engineering)||大学院創造理工学研究科||2019||通年|