The Experts below are selected from a list of 159615354 Experts worldwide ranked by ideXlab platform
Yili Kang - One of the best experts on this subject based on the ideXlab platform.
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mesoscopic structure characterization of plugging zone for lost circulation control in fractured reservoirs based on photoelastic experiment
Journal of Natural Gas Science and Engineering, 2020Co-Authors: Xiaopeng Yan, Yili Kang, Lijun You, Xiangyu Shang, Haoran JingAbstract:Abstract Drilling fluid loss into formation fractures is one of the most common and costly problems encountered during the exploration and development of oil and gas resources. The stability of fracture plugging zone formed by lost circulation materials has a great impact on the lost circulation control effect. Mesoscale structure stability of force chain, which is the way to transferring contact force between particles, determines the strength of the macroscale plugging zone. In the current paper, photoelastic method is introduced and photoelastic experimental system is developed to characterize the mesoscopic structure evolution of plugging zone under shear. The key parameters for the mesoscopic structure characterization of fracture plugging zone are proposed, including the proportion, distribution, elastic energy, and angle of the strong force chain. Experimental results show that the mesoscopic structure of plugging zone experiences continuous formation and destruction during the shear process. Initially, the distribution of the mesoscopic force chain under a vertical load presents a vertical tree branch structure. Then, the proportion of force chains in the horizontal direction increases and form a staggered network structure after a horizontal shear force is continuously applied. During the shear process of plugging zone, the mesoscopic force chain network experiences rearrangement and structural failure. The distribution density of elastic energy in the particles transferring strong force is reduced. Based on the developed photoelastic experimental system, the mesoscopic structure evolution of the plugging zone is accurately described. It can be used to guide the selection of the lost circulation materials and optimization of the loss control formula.
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structural failure mechanism and strengthening method of fracture plugging zone for lost circulation control in deep naturally fractured reservoirs
Petroleum Exploration and Development, 2020Co-Authors: Xu Chengyuan, Yili Kang, Xiaopeng Yan, Lijun You, Jingyi ZhangAbstract:Abstract Focused on the lost circulation control in deep naturally fractured reservoirs, the multiscale structure of fracture plugging zone is proposed based on the theory of granular matter mechanics, and the structural failure pattern of plugging zone is developed to reveal the plugging zone failure mechanisms in deep, high temperature, high pressure, and high in-situ stress environment. Based on the fracture plugging zone strength model, key performance parameters are determined for the optimal selection of loss control material (LCM). Laboratory fracture plugging experiments with new LCM are carried out to evaluate the effect of the key performance parameters of LCM on fracture plugging quality. LCM selection strategy for fractured reservoirs is developed. The results show that the force chain formed by LCMs determines the pressure stabilization of macro-scale fracture plugging zone. Friction failure and shear failure are the two major failure patterns of fracture plugging zone. The strength of force chain depends on the performance of micro-scale LCM, and the LCM key performance parameters include particle size distribution, fiber aspect ratio, friction coefficient, compressive strength, soluble ability and high temperature resistance. Results of lab experiments and field test show that lost circulation control quality can be effectively improved with the optimal material selection based on the extracted key performance parameters of LCMs.
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analytical model of plugging zone strength for drill in fluid loss control and formation damage prevention in fractured tight reservoir
Journal of Petroleum Science and Engineering, 2017Co-Authors: Chengyuan Xu, Yili Kang, Fei ChenAbstract:Developed fractures are beneficial for the efficient development of tight reservoir. They also lead to drill-in fluid loss and induce severe formation damage. Fracture plugging with loss control material (LCM) is the most common way to control drill-in fluid loss in fractured formation. Fracture plugging effect largely depends on the strength of fracture plugging zone, because in most cases plugging failure is caused by the strength failure of plugging zone. However, the effects of LCM mechanical and geometric parameters on plugging zone strength are still unclear. Moreover, traditional LCM selection is mainly performed by trial-and-error method, due to the lack of mathematical models. This paper develops an analytical model for plugging zone strength accounting for the frictional failure and shear failure of fracture plugging zone. Effects of LCM mechanical and geometric properties on plugging zone strength are analyzed. The proposed model is validated by laboratory data. Application procedure of the proposed model to drill-in fluid loss control is developed and successfully applied to the field case study in Sichuan basin, China. The modelling results show that particle-particle friction angle, particle-fiber friction angle, fiber tensile strength, D90 degradation rate, and friction angle between plugging zone and fracture surface are main mechanical parameters affecting the plugging zone strength. Particle size distribution, aspect ratio and initial angle of fiber, and plugging zone porosity are main geometric parameters during loss control. Single LCM parameters are applied to the selection of LCM type. Plugging zone parameters are used for the determination of optimal LCM concentration. Reasonable combination of rigid granule, fiber and elastic particle can create a synergy effect to optimize the plugging zone strength and loss control effect.
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fracture plugging optimization for drill in fluid loss control and formation damage prevention in fractured tight reservoir
Journal of Natural Gas Science and Engineering, 2016Co-Authors: Yili Kang, Fei Chen, Zhenjiang YouAbstract:Well-developed natural fractures are beneficial for the economic and efficient development of tight reservoirs. However, they also lead to drill-in fluid loss and induced severe formation damage. Fracture plugging with loss control material (LCM) is the most common way to control lost circulation. Fracture plugging effect largely depends on the fracture propagation pressure, because plugging failure is mainly caused by fracture propagation in fractured formation. Nevertheless, the effects of the plugging parameters on the fracture propagation pressure are still unclear. The current paper develops a mathematical model for fracture propagation pressure accounting for fracture plugging. Key indexes are proposed for fracture plugging optimization based on parameter analysis. Laboratory experiments are conducted to select reasonable LCM type and concentration. The application procedure of the proposed model to drill-in fluid loss control is presented and successfully applied to field case study. The modelling results show that the plugging zone length, width and permeability are the major plugging parameters that affect the fracture propagation pressure. The larger the plugging zone width and the smaller the plugging zone length and permeability, the higher the fracture propagation pressure. Maximum plugging pressure, total loss volume before sealing and D90 degradation rate are proposed as the three indexes for LCM selection. Experimental results show that the combination of rigid granule, fiber and elastic particle can create a synergistic effect to optimize the fracture plugging effect. For the 500 μm width fracture, the optimal concentrations for rigid granule, fiber and elastic particle are 5.0%, 1.5% and 2.5%, respectively.
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prevention of fracture propagation to control drill in fluid loss in fractured tight gas reservoir
Journal of Natural Gas Science and Engineering, 2014Co-Authors: Yili Kang, Long Tang, Fei ChenAbstract:Abstract Developed fractures are beneficial for the economic and efficient development of tight gas reservoir. But they will lead to drill-in fluid loss and induce serious formation damage. Preventing natural fractures propagation is the key to control drill-in fluid loss in the fractured reservoir. Plugging and sealing the fracture loss channel with loss control material (LCM) can improve the fracture propagation pressure (FPP) effectively. However, the main parameters that affect the improved FPP are not clear. To our best knowledge, few papers have been published on the comprehensive parametric analysis for improved FPP to select reasonable LCM and control drill-in loss in fractured tight gas reservoir. In this paper, we develop a mathematic model to analyze the parameters that affect the FPP after plugging. Laboratory experiment is conducted to select reasonable LCM based on the parametric analysis. Study results show that formation stress anisotropy, elastic modulus, fracture length, fracture pressure and plugging location are the main parameters that impact the improved FPP. According to the analysis results, maximum plugging pressure and total loss volume before sealing are proposed as the key indexes for LCM selection. Experiment results show that reasonable combination of rigid granule, fiber and elastic particle can create a synergy effect to effectively control drill-in fluid loss in fracture tight gas reservoir.
Ximin Zhang - One of the best experts on this subject based on the ideXlab platform.
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hydrogen production by coal gasification in supercritical water with a fluidized bed reactor
International Journal of Hydrogen Energy, 2010Co-Authors: Youjun Lu, Bo Liao, Ximin ZhangAbstract:The technology of supercritical water gasification of coal can converse coal to hydrogen-rich gaseous products effectively and cleanly. However, the slugging problem in the tubular reactor is the bottleneck of the development of continuous large-scale hydrogen production from coal. The reaction of coal gasification in supercritical water was analyzed from the point of view of thermodynamics. A chemical equilibrium model based on Gibbs free energy minimization was adopted to predict the yield of gaseous products and their fractions. The gasification reaction was calculated to be complete. A supercritical water gasification system with a fluidized bed reactor was applied to investigate the gasification of coal in supercritical water. 24 wt% coal-water-slurry was continuously transported and stably gasified without plugging problems; a hydrogen yield of 32.26 mol/kg was obtained and the hydrogen fraction was 69.78%. The effects of operational parameters upon the gasification characteristics were investigated. The recycle of the liquid residual from the gasification system was also studied.
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hydrogen production by biomass gasification in supercritical water with a fluidized bed reactor
International Journal of Hydrogen Energy, 2008Co-Authors: Hui Jin, Ximin Zhang, Liejin Guo, Changqing Cao, Xu GuoAbstract:Abstract Hydrogen production by biomass gasification in supercritical water (SCW) is a promising technology for utilizing high moisture content biomass, but reactor plugging is a critical problem for biomass gasification in the tubular reactor. A novel SCW fluidized bed system for biomass gasification was developed successfully in State Key Laboratory of Multiphase Flow in Power Engineering (SKLMF) to prevent the plugging and it was designed for the temperature up to 923 K and the pressure up to 30 MPa. Model compound (glucose) and real biomass (corn cob) were gasified under SCW conditions to generate hydrogen-rich fuel gas and a performance testing of the new SCW fluidized bed system was conducted. The product gas composed of H2, CH4, CO2, CO and small amount of C2H4 and C2H6 was obtained. The effects of solution concentration, temperature, pressure and oxidant concentration on gasification were studied. 30 wt% glucose and 18 wt% corn cob feedstocks were continually and stably gasified and reactor plugging was not observed. The results showed that using fluidized bed reactor for biomass gasification in SCW has many advantages and good prospects.
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hydrogen production by biomass gasification in supercritical water a parametric study
International Journal of Hydrogen Energy, 2006Co-Authors: Liejin Guo, Ximin Zhang, Xiaohong Hao, Qiuhui YanAbstract:Hydrogen production by biomass gasification in supercritical water is a promising technology for utilizing high moisture content biomass, but reactor plugging is a critical problem when feedstocks with high biomass content are gasified. The objective of this paper is to prevent the plugging problem by studying the effects of the various parameters on biomass gasification in supercritical water. These parameters include pressure, temperature, residence time, reactor geometrical configuration, reactor types, heating rate, reactor wall properties, biomass types, biomass particle size, catalysts and solution concentration. Biomass model compounds (glucose, cellulose) and real biomass are used in this work. All the biomasses have been successfully gasified and the product gas is composed of hydrogen, carbon dioxide, methane, carbon monoxide and a small amount of ethane and ethylene. The results show that the gas yield of biomass gasification in supercritical water is sensitive to some of the parameters and the ways of reducing reactor plugging are obtained.
Michael J. Mckenna - One of the best experts on this subject based on the ideXlab platform.
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operative management of superior semicircular canal dehiscence
Laryngoscope, 2005Co-Authors: Michael J. Mckenna, Dennis S Poe, Anthony A MikulecAbstract:Objective: To assess the outcomes of patients undergoing surgical management of superior semicircular canal dehiscence (SSCD). Study Design: Retrospective review. Methods: The medical records of all patients undergoing surgical treatment for SSCD at our institution between 2000 and 2004 were reviewed. Results: Eleven patients underwent unilateral operative management via a middle fossa approach. Ten patients were treated successfully by canal plugging and one unsuccessfully by canal re-roofing. Plugging of SSCD provided resolution of sound- and pressure-induced nystagmus, autophony, and conductive hearing loss (HL). One patient experienced a mild high-frequency sensorineural HL and two patients experienced both a mild high-frequency sensorineural HL and a reduction in vestibular function. Two additional patients underwent exploration for SSCD but were found to have a thin layer of bone overlying the canal. Conclusions: Plugging of the SSCD, while efficacious in alleviating the symptoms of the disease, may cause loss of labyrinthine function beyond the superior canal.
Xiangyu Shang - One of the best experts on this subject based on the ideXlab platform.
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mesoscopic structure characterization of plugging zone for lost circulation control in fractured reservoirs based on photoelastic experiment
Journal of Natural Gas Science and Engineering, 2020Co-Authors: Xiaopeng Yan, Yili Kang, Lijun You, Xiangyu Shang, Haoran JingAbstract:Abstract Drilling fluid loss into formation fractures is one of the most common and costly problems encountered during the exploration and development of oil and gas resources. The stability of fracture plugging zone formed by lost circulation materials has a great impact on the lost circulation control effect. Mesoscale structure stability of force chain, which is the way to transferring contact force between particles, determines the strength of the macroscale plugging zone. In the current paper, photoelastic method is introduced and photoelastic experimental system is developed to characterize the mesoscopic structure evolution of plugging zone under shear. The key parameters for the mesoscopic structure characterization of fracture plugging zone are proposed, including the proportion, distribution, elastic energy, and angle of the strong force chain. Experimental results show that the mesoscopic structure of plugging zone experiences continuous formation and destruction during the shear process. Initially, the distribution of the mesoscopic force chain under a vertical load presents a vertical tree branch structure. Then, the proportion of force chains in the horizontal direction increases and form a staggered network structure after a horizontal shear force is continuously applied. During the shear process of plugging zone, the mesoscopic force chain network experiences rearrangement and structural failure. The distribution density of elastic energy in the particles transferring strong force is reduced. Based on the developed photoelastic experimental system, the mesoscopic structure evolution of the plugging zone is accurately described. It can be used to guide the selection of the lost circulation materials and optimization of the loss control formula.
Fei Chen - One of the best experts on this subject based on the ideXlab platform.
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analytical model of plugging zone strength for drill in fluid loss control and formation damage prevention in fractured tight reservoir
Journal of Petroleum Science and Engineering, 2017Co-Authors: Chengyuan Xu, Yili Kang, Fei ChenAbstract:Developed fractures are beneficial for the efficient development of tight reservoir. They also lead to drill-in fluid loss and induce severe formation damage. Fracture plugging with loss control material (LCM) is the most common way to control drill-in fluid loss in fractured formation. Fracture plugging effect largely depends on the strength of fracture plugging zone, because in most cases plugging failure is caused by the strength failure of plugging zone. However, the effects of LCM mechanical and geometric parameters on plugging zone strength are still unclear. Moreover, traditional LCM selection is mainly performed by trial-and-error method, due to the lack of mathematical models. This paper develops an analytical model for plugging zone strength accounting for the frictional failure and shear failure of fracture plugging zone. Effects of LCM mechanical and geometric properties on plugging zone strength are analyzed. The proposed model is validated by laboratory data. Application procedure of the proposed model to drill-in fluid loss control is developed and successfully applied to the field case study in Sichuan basin, China. The modelling results show that particle-particle friction angle, particle-fiber friction angle, fiber tensile strength, D90 degradation rate, and friction angle between plugging zone and fracture surface are main mechanical parameters affecting the plugging zone strength. Particle size distribution, aspect ratio and initial angle of fiber, and plugging zone porosity are main geometric parameters during loss control. Single LCM parameters are applied to the selection of LCM type. Plugging zone parameters are used for the determination of optimal LCM concentration. Reasonable combination of rigid granule, fiber and elastic particle can create a synergy effect to optimize the plugging zone strength and loss control effect.
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fracture plugging optimization for drill in fluid loss control and formation damage prevention in fractured tight reservoir
Journal of Natural Gas Science and Engineering, 2016Co-Authors: Yili Kang, Fei Chen, Zhenjiang YouAbstract:Well-developed natural fractures are beneficial for the economic and efficient development of tight reservoirs. However, they also lead to drill-in fluid loss and induced severe formation damage. Fracture plugging with loss control material (LCM) is the most common way to control lost circulation. Fracture plugging effect largely depends on the fracture propagation pressure, because plugging failure is mainly caused by fracture propagation in fractured formation. Nevertheless, the effects of the plugging parameters on the fracture propagation pressure are still unclear. The current paper develops a mathematical model for fracture propagation pressure accounting for fracture plugging. Key indexes are proposed for fracture plugging optimization based on parameter analysis. Laboratory experiments are conducted to select reasonable LCM type and concentration. The application procedure of the proposed model to drill-in fluid loss control is presented and successfully applied to field case study. The modelling results show that the plugging zone length, width and permeability are the major plugging parameters that affect the fracture propagation pressure. The larger the plugging zone width and the smaller the plugging zone length and permeability, the higher the fracture propagation pressure. Maximum plugging pressure, total loss volume before sealing and D90 degradation rate are proposed as the three indexes for LCM selection. Experimental results show that the combination of rigid granule, fiber and elastic particle can create a synergistic effect to optimize the fracture plugging effect. For the 500 μm width fracture, the optimal concentrations for rigid granule, fiber and elastic particle are 5.0%, 1.5% and 2.5%, respectively.
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prevention of fracture propagation to control drill in fluid loss in fractured tight gas reservoir
Journal of Natural Gas Science and Engineering, 2014Co-Authors: Yili Kang, Long Tang, Fei ChenAbstract:Abstract Developed fractures are beneficial for the economic and efficient development of tight gas reservoir. But they will lead to drill-in fluid loss and induce serious formation damage. Preventing natural fractures propagation is the key to control drill-in fluid loss in the fractured reservoir. Plugging and sealing the fracture loss channel with loss control material (LCM) can improve the fracture propagation pressure (FPP) effectively. However, the main parameters that affect the improved FPP are not clear. To our best knowledge, few papers have been published on the comprehensive parametric analysis for improved FPP to select reasonable LCM and control drill-in loss in fractured tight gas reservoir. In this paper, we develop a mathematic model to analyze the parameters that affect the FPP after plugging. Laboratory experiment is conducted to select reasonable LCM based on the parametric analysis. Study results show that formation stress anisotropy, elastic modulus, fracture length, fracture pressure and plugging location are the main parameters that impact the improved FPP. According to the analysis results, maximum plugging pressure and total loss volume before sealing are proposed as the key indexes for LCM selection. Experiment results show that reasonable combination of rigid granule, fiber and elastic particle can create a synergy effect to effectively control drill-in fluid loss in fracture tight gas reservoir.
