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Processes
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Risk Assessment and Reliability Engineering of Process Operations
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Risk Assessment and Reliability Engineering of Process Operations

A special issue of Processes (ISSN 2227-9717). This special issue belongs to the section "Process Control and Monitoring".

Deadline for manuscript submissions: closed (29 February 2024) | Viewed by 46259

Special Issue Editors

Dr. Xinhong Li

E-Mail Website
Guest Editor
Centre for Pipeline Risk and Reliability Engineering (CPRRE), Department of Safety Engineering, Xi'an University of Architecture and Technology, Xi'an, China
Interests: dynamic risk assessment and process safety management
Special Issues, Collections and Topics in MDPI journals
Dr. Shangyu Yang

E-Mail
Guest Editor
CNPC Tubular Goods Research Institute, Xi’an, China
Interests: safety and reliability of oil and gas strings
Dr. Huixing Meng

E-Mail Website
Guest Editor
School of Mechatronical Engineering, Beijing Institute of Technology, Beijing, China
Interests: intelligent maintenance and risk management

Special Issue Information

Dear Colleagues,

The complexity of the processes and the nature of volatile petroleum products lead to the frequent occurrence of unexpected failures or accidents, which pose a severe threat to human safety, the environment, and assets. The operations in the process industry are challenged by a series of adverse factors, e.g., harsh environment, corrosion, fatigue, and natural hazards. The process industry is implementing risk assessment to identify and manage potential failure modes that can interrupt operation processes. Besides, a series of techniques were utilized to improve the reliability of the process system. Although many efforts were made to oversee the operation management to ensure asset integrity, and human and environmental safety, failures and accidents still occur and result in various consequences. Recently, the exploration, exploitation, and transportation of emerging energy have brought new questions and challenges. Thus, improved knowledge of safety, reliability, and risk in the process industry is urgent.

This Special Issue pays particular attention to safety, risk, and reliability in process industries including theory, method, and engineering application, to cope with the challenges of harsh environments, major accidents, and new energy.

Potential topics include, but are not limited to, the following:

  • Structural design method in harsh environment
  • Structural safety assessment of process facilities
  • Accident modeling in process operations
  • Risk identification, analysis, assessment
  • Emergency decision-making and management
  • Technical Safety and Loss Prevention
  • Non-destructive detection technique for process facilities
  • Reliability assessment process facilities
  • Transportation safety of emerging energy
  • Fault Diagnostics and Prognostics
  • Risk early-warning
  • AI in safety and reliability
  • Resilience engineering

Dr. Xinhong Li
Dr. Shangyu Yang
Dr. Huixing Meng
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Processes is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • risk assessment
  • system safety
  • reliability engineering
  • process industry

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Published Papers (28 papers)

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Research

18 pages, 14278 KiB  
Article
Research on Thread Seal Failure Mechanism of Casing Hanger in Shale Gas Wells and Prevention Measures
by Yisheng Mou, Yonggang Xie, Fengqi Wei, Han Zhao and Lihong Han
Processes 2024, 12(6), 1253; https://doi.org/10.3390/pr12061253 - 18 Jun 2024
Viewed by 712
Abstract
The strength and sealing failure of the connecting thread of the casing head mandrel hanger causes huge economic losses. One of the major challenges is the thread seal failure mechanism of the casing hanger in the wellhead during pressure testing in shale gas [...] Read more.
The strength and sealing failure of the connecting thread of the casing head mandrel hanger causes huge economic losses. One of the major challenges is the thread seal failure mechanism of the casing hanger in the wellhead during pressure testing in shale gas wells. In order to analyze the failure causes of connecting threads and put forward improvement measures, a typical case of a well accompanied by a hanger seal failure is analyzed in this paper, and a series of material tests are carried out. The microstructure and mechanical properties of casing materials and hanger materials could meet the field requirements. It is concluded that both the hanger material and casing material are characterized with significant ductile fracture. A three-dimensional model of the hanger and casing system is established, and the mechanical behavior is calculated for the connecting thread under different working conditions. The results showed that the connection degree of the hanger–casing is insufficient at the torque recommended by the manufacturer because of the difference in wall thickness between the box thread of the hanger and the box thread of the joint according to the connection degree of the coupling casing. It is seen that the high contact pressure ring of zone three on the sealing surface plays an effective sealing role under the manufacturer’s recommended torque (20,465 N·m). Finally, when the torque is increased by 25%, the maximum contact pressure between the pin thread of the casing and the box thread of the hanger can fully meet the internal pressure from the wellbore pressure test and the internal pressure strength required for subsequent operations. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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22 pages, 9444 KiB  
Article
Research on the Mechanical Properties and Structural Optimization of Pipe String Joint under Deep Well Fracturing Operation
by Chentao Ma, Yonggang Duan, Kun Huang, Qianwen Mo, Qi Chen and Tiesong Fu
Processes 2024, 12(4), 835; https://doi.org/10.3390/pr12040835 - 20 Apr 2024
Viewed by 932
Abstract
In order to reduce the failure accidents caused by the insufficient strength of fracturing string joints, theoretical calculation and string design methods were adopted to conduct finite element calculations on commonly used long circular threads. The distribution laws of stress and contact pressure [...] Read more.
In order to reduce the failure accidents caused by the insufficient strength of fracturing string joints, theoretical calculation and string design methods were adopted to conduct finite element calculations on commonly used long circular threads. The distribution laws of stress and contact pressure of long round threads were obtained, a non-standard special thread was designed, and a finite element model of the joint of the casing was established. Considering different make-up torques, tensile loads, and tensile torque loads within a certain range, the stress variation law of the special casing threaded joint under this design size was analyzed. Finally, the stress and contact pressure variation law on the threaded tooth was analyzed under different structures, working conditions, and wall thickness parameters. The thread strength and sealing function were compared under various parameters. The results showed that the smaller the wall thickness of the joints, the greater the contact pressure at the threaded tooth. Among them, the contact pressure of the external threaded tooth is too high, and is prone to the sticking phenomenon. The distribution of contact pressure in the middle section is relatively reasonable. Compared with the original structure, the new structure significantly reduces the contact pressure at the head and tail ends of the threaded connection, reducing the risk of sticking. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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23 pages, 12261 KiB  
Article
Reliability Analysis of Dynamic Sealing Performance in the Radial Hydraulic Drilling Technique
by Lin Chai, Yongsheng Liu, Guoqiang Chen, Qiang Sun, Wenlong Gao and Zijun Dou
Processes 2024, 12(4), 807; https://doi.org/10.3390/pr12040807 - 17 Apr 2024
Viewed by 1044
Abstract
Traditional coiled tubing radial drilling with the same diameter cannot support deep and ultra-deep wells for high-pressure hydraulic jet drilling due to small diameter and sizeable hydraulic loss over long distances. The novel downhole movable pipe radial hydraulic drilling technique extracts a small [...] Read more.
Traditional coiled tubing radial drilling with the same diameter cannot support deep and ultra-deep wells for high-pressure hydraulic jet drilling due to small diameter and sizeable hydraulic loss over long distances. The novel downhole movable pipe radial hydraulic drilling technique extracts a small diameter high-pressure injection pipe from the (tubing pipe) oil pipe and then drills it horizontally into the formation to form a radial hole. Dynamic sealing is the core of this technology, which achieves high-pressure fluid sealing while ensuring the injection pipe smoothly slides out of the oil pipe. A sealing tool is designed between the tubing and the injection pipe to prevent the leakage of high-pressure fluid. In this paper, the finite element model of the sealing tool was established, and the deformation and stress of the sealing tool under different interference and fluid pressure were simulated and analyzed. The relationship between stress distribution and contact pressure under the corresponding conditions was obtained. The results show that the von Mises stress increases significantly with the increase in fluid pressure under certain interference conditions. When the fluid pressure was 35 MPa, 52 MPa, and 70 MPa, the maximum von Mises stress was 29.65 MPa, 30.87 MPa, and 32.47 MPa, respectively, within a reasonable range. The stress peak area changes simultaneously, indicating that the possible damage location changes with the fluid pressure change. The maximum contact pressure between the sealing ring and the smooth rod increases with interference and fluid pressure, which always meets the sealing conditions. A laboratory test bench was built to test the high-pressure sealing performance of the sealing tool. Combined with the simulation data and test results, the downhole continuous rod dynamic sealing tool was modified to provide theoretical guidance for practical application. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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12 pages, 3110 KiB  
Article
Study on Erosion Wear of Single- and Double-Orifice Throttling Tools for Underground Coal Gasification
by Jianjun Wang, Bingchao Zhou, Jianglong Fu, Siqi Yang, Chao Wang and Xiangyi Ren
Processes 2024, 12(1), 120; https://doi.org/10.3390/pr12010120 - 2 Jan 2024
Cited by 1 | Viewed by 1190
Abstract
In underground coal gasification, as a choke regulating the formation gas lift pressure, the throttling tool can effectively reduce the production cost, the number of ground heating and insertion equipment, and gas consumption. Because in this process, the coal is transformed into composite [...] Read more.
In underground coal gasification, as a choke regulating the formation gas lift pressure, the throttling tool can effectively reduce the production cost, the number of ground heating and insertion equipment, and gas consumption. Because in this process, the coal is transformed into composite synthetic gas through a series of technical treatments, the throttling tool is in a working environment with high temperature and pressure. In the process of transportation of combined synthetic gas, the pulverized coal parts produced by incomplete coal combination move with the gas in the throttling tool. The high temperature and high-pressure gas carrying large-diameter pressed coal parts will cause serial erosion and wear to the throttling device, resulting in failure and well-controlled safety risks. Therefore, according to the Joule–Thomson effect, this paper independently designs downhole throttling tools with single- and double-hole structures. According to actual field conditions, the erosion wear of throttling tools with different systems in high-temperature gas–solid two-phase flow was simulated and predicted, and the internal flow field characteristics of throttling means were analyzed. The difference between the wall wear distribution, wall collision position, and wall erosion effect of different structure throttling mechanisms with the change in gas velocity was investigated, which guides the practical use of the subsequent throttling tools. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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17 pages, 10595 KiB  
Article
Simulation and Experiment on Elimination for the Bottom-Sitting Adsorption Effect of a Submersible Based on a Submerged Jet
by Hao Zhang, Cong Ye, Peng Gong, Fengwei Xu, Dongjing Zhang, Shuguang Cong and Shuai Liu
Processes 2023, 11(12), 3452; https://doi.org/10.3390/pr11123452 - 18 Dec 2023
Viewed by 1042
Abstract
When a submersible is sitting on a seabed, it could lose buoyancy because of the bottom-sitting adsorption effect. In this article, a numerical calculation model and experimental scheme for eliminating the bottom-sitting adsorption effect of under-sea equipment were established. An analysis of the [...] Read more.
When a submersible is sitting on a seabed, it could lose buoyancy because of the bottom-sitting adsorption effect. In this article, a numerical calculation model and experimental scheme for eliminating the bottom-sitting adsorption effect of under-sea equipment were established. An analysis of the hydrostatic pressure variation on a submersible’s bottom was carried out, and a submerged water jet which was based on the method of soil liquefaction was proposed to solve the problem of reducing hydrostatic pressure. It was shown that a water jet could liquefy soil to restore hydrostatic pressure on the submersible’s bottom, and there was an optimal jet velocity to form the largest liquefied soil thickness. A rectangular pulsed jet was the best way to liquefy soil in terms of efficiency and the liquefaction degree, which can be seen from the calculation of the two-dimensional two-phase flow. Through the calculation of the three-dimensional two-phase flow, it was found that the soil liquefaction developed from the periphery to the center, and a variation in jet liquefaction with the top wall constraint was obtained. Finally, an experiment was carried out to prove that a submerged water jet could eliminate the bottom-sitting adsorption effect of a submersible. The results showed that the submerged jet was an efficient way to liquefy soil, and a submersible could quickly recover hydrostatic pressure on the bottom and refloat up independently. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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18 pages, 5827 KiB  
Article
Experimental and Numerical Study for Gas Release and Dispersion on Offshore Platforms
by Fengpu Xiao, Yanan Li, Jun Zhang, Hai Dong, Dongdong Yang and Guoming Chen
Processes 2023, 11(12), 3437; https://doi.org/10.3390/pr11123437 - 15 Dec 2023
Viewed by 1183
Abstract
Accidental gas release is a major triggering event for the offshore oil and gas industry. This paper focuses on the experimental and numerical investigation for dispersion behavior of released gas on offshore platforms. For this purpose, an experimental system is designed and developed [...] Read more.
Accidental gas release is a major triggering event for the offshore oil and gas industry. This paper focuses on the experimental and numerical investigation for dispersion behavior of released gas on offshore platforms. For this purpose, an experimental system is designed and developed to investigate gas release and dispersion. A series of experiments are carried out, among which the scenarios with constant leakage rates and time-varying leakage rates are both emphasized. The gas concentrations at different sampling points are obtained to study the dispersion behavior and accumulation characteristics of the released gas. Furthermore, a numerical computational fluid dynamics model is established to replicate the experimental scenarios. Good agreement between experimental data and CFD simulation results is observed by calculating a series of statistical performance measures. The developed numerical model is subsequently utilized to investigate a gas release scenario on a practical offshore platform, in which a fully transient leakage rate is adopted considering the response of process protection measures. The developed numerical model could provide support for risk assessment and optimization of contingency plans against gas release accidents in offshore facilities. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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12 pages, 1302 KiB  
Article
Research on the Prediction of Wax Deposition Thickness on Pipe Walls Based on the Optimal Weighted Combination Model
by Wenbo Jin, Qing Quan, Kemin Dai, Zongxiao Ren and Jing Guan
Processes 2023, 11(12), 3363; https://doi.org/10.3390/pr11123363 - 4 Dec 2023
Viewed by 891
Abstract
Wax deposition seriously affects the safe and economic operation of pipelines. Mastering the variation laws of wax deposition thickness is the premise of formulating reasonable pigging schemes. Although the GM (1,1) model (a kind of gray model) is an effective method for predicting [...] Read more.
Wax deposition seriously affects the safe and economic operation of pipelines. Mastering the variation laws of wax deposition thickness is the premise of formulating reasonable pigging schemes. Although the GM (1,1) model (a kind of gray model) is an effective method for predicting wax deposition thickness on pipe walls, its prediction accuracy is easily affected by the smoothness of the original sequence. The improved GM (1,1) was established by introducing the idea of translation transformation, and an optimal weighted combination model based on the traditional gray model and a logarithmic function model was proposed. The differences in the predicted results of the established models were compared and analyzed through indoor wax deposition experimental data. The research results indicate that the optimal weighted combination model has the highest fitting accuracy, followed by the logarithmic function model and the improved GM (1,1), while the fitting accuracy of the traditional gray model is poor. When the number of modeling samples is five, the average relative error and root mean square error of the prediction results of the optimal weighted combination model are 1.313% and 0.021, respectively, which shows the highest prediction accuracy. When the number of modeling samples is six, the average relative error and root mean square error of the optimal weighted combination model are 2.143% and 0.031, respectively, and its prediction accuracy is still the highest. Overall, the optimal weighted combination model has the advantages of high accuracy and easy implementation, and has strong promotion and application value. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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23 pages, 8295 KiB  
Article
Research on the Mechanism and Control Strategy of Microbubble Cleaning Sludge
by Bing Liu, Haitao Zhao, Changjiang Li, Heng Guan and Fengde Wang
Processes 2023, 11(10), 2915; https://doi.org/10.3390/pr11102915 - 5 Oct 2023
Viewed by 1164
Abstract
Microbubble cleaning technology has the characteristics of environmental protection and low energy consumption and has been initially applied in the field of oil sludge cleaning. For the controllability of microbubbles in the cleaning process, this paper adopted the numerical simulation method to quantitatively [...] Read more.
Microbubble cleaning technology has the characteristics of environmental protection and low energy consumption and has been initially applied in the field of oil sludge cleaning. For the controllability of microbubbles in the cleaning process, this paper adopted the numerical simulation method to quantitatively study the growth and collapse mechanism of bubbles in the cleaning process, the influence law of flow field, and parameter changes on the dynamic behavior of bubbles from the perspective of micro-dynamics. It was found that the dynamic characteristics of the flow field around the bubble in the free field show a symmetrical distribution, while the motion of the fluid near the wall is blocked by the wall, and the flow field between the bubble and the wall becomes irregular. It was also found that the large amplitude pressure changes in microbubbles produced a “plastic hinge” alternating impact on the wall, the bubble collapse, and wall pulsation pressure change are mainly controlled by the driving pressure. The liquid temperature mainly affects the dynamic characteristics of the bubble by causing a change in the viscosity of the medium. Under the condition of Pd = 0.1 MPa and γ = 1.5, when the liquid viscosity decreases from 0.110 to 0.00314 Pa·s, the maximum pressure affected by the first bubble collapse increases from 200.71 to 317.74 Kpa. Compared with the bubble distribution, the impact of increasing the number of bubbles on the wall is more significant. Under the condition of γ = 1 and Pd = 0.1 MPa, compared with the single bubble, the pulse pressure of nine bubbles’ collapse on the wall increases by 100 KPa. The research results can provide technical support for the development of microbubble cleaning technology. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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12 pages, 2981 KiB  
Article
Investigating Erosion of String in Underground Hydrogen Storage under High Flow Velocity
by Lixia Zhu, Lifeng Li, Jinheng Luo, Ziyue Han, Shuyi Xie, Tao Yu and Qing Liu
Processes 2023, 11(10), 2894; https://doi.org/10.3390/pr11102894 - 30 Sep 2023
Viewed by 1077
Abstract
Underground hydrogen storage represents an innovative approach to energy storage. To ensure the secure operation of subterranean hydrogen storage strings, a computational fluid dynamics (CFD) methodology was employed to devise an erosion assessment model tailored for high-velocity conditions. The research delved into the [...] Read more.
Underground hydrogen storage represents an innovative approach to energy storage. To ensure the secure operation of subterranean hydrogen storage strings, a computational fluid dynamics (CFD) methodology was employed to devise an erosion assessment model tailored for high-velocity conditions. The research delved into the erosion and abrasion dynamics of these storage strings when subjected to high-speed gas flows. This study further examined the impacts of gas velocity, particle size, pipe material, and pipe wall corrosion imperfections on flow patterns and erosion wear rates across the column. The outcomes revealed several noteworthy trends. As fluid velocity increased, the flow field’s maximum pressure augmented, while it decreased alongside enlarging pipe diameter and particle size. P110 pipe material exhibited higher maximum pressure in comparison to N80. The effect of centrifugal force induced pressure to surge from the inner to the outer portion of the column. In the curved pipe section’s outer wall, the frequent occurrence of high-angle collisions engendered elevated rates of erosion wear over time. Particularly noteworthy was the observation of the highest erosion rate in curved pipes showcasing three corrosion defects, attributed to the backflow effects of erosion pits. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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11 pages, 2050 KiB  
Article
Development of a Design Method for Casing and Tubing Strings under Complex Alternating Loads
by Jianjun Wang, Dening Li, Xu Du, Hongjie Li and Shangyu Yang
Processes 2023, 11(9), 2582; https://doi.org/10.3390/pr11092582 - 29 Aug 2023
Cited by 1 | Viewed by 1991
Abstract
With the escalating intricacy of downhole operational scenarios, encompassing frequent well cycling, acidification, multi-stage fracturing, steam injection, and intensive extraction, the efficacy of traditional casing-string-design methods rooted in strength considerations is progressively unveiling its limitations. Henceforth, it becomes imperative to establish string-design method [...] Read more.
With the escalating intricacy of downhole operational scenarios, encompassing frequent well cycling, acidification, multi-stage fracturing, steam injection, and intensive extraction, the efficacy of traditional casing-string-design methods rooted in strength considerations is progressively unveiling its limitations. Henceforth, it becomes imperative to establish string-design method standards that embrace the entirety of a well’s lifecycle, encompassing the phases of drilling, completion, fracturing, and production operations. Beginning with an analysis of the advantages and limitations of traditional casing-string-design methods, this paper introduces the features of strain and sealing design methods developed for the full lifecycle of the string. The strain design method, a departure from conventional design philosophies, enables the design concept of the controllable deformation of the pipe string. The sealing design method currently stands as the sole standard method for the design of tubing strings. Simultaneously, this paper proposes the establishment of a time dimension-based lifecycle pipe string-design method standard. This approach considers the trend of pipe strength degradation, effectively addressing the safety concerns related to pipe string design in production and operation. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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18 pages, 14646 KiB  
Article
A Study on the Mechanism of Casing Deformation and Its Control Strategies in Shale Oil Hydraulic Fracturing
by Nan Zhang, Peng Wang, Junliang Li, Wenhai Ma, Xiaochuan Zhang, Hongtao Zhang, Chenggang Jiang, Weiming Huang, Xinzhu Feng and Shuwei Liu
Processes 2023, 11(8), 2437; https://doi.org/10.3390/pr11082437 - 13 Aug 2023
Viewed by 1693
Abstract
The problem of casing deformation caused by large-scale hydraulic fracturing in shale oil wells severely restricts the efficient development of Gulong shale oil. In order to clarify the mechanism of casing deformation in shale oil wells, comprehensive analysis was conducted on engineering factors, [...] Read more.
The problem of casing deformation caused by large-scale hydraulic fracturing in shale oil wells severely restricts the efficient development of Gulong shale oil. In order to clarify the mechanism of casing deformation in shale oil wells, comprehensive analysis was conducted on engineering factors, multi-arm caliper logging, seismic attributes, and the distribution characteristics of casing deformations. This study shows that casing strength, cementing quality, and wellbore curvature are not the main controlling factors for casing deformation. Casing deformation is caused by the communication between hydraulic fractures and natural fractures during the fracturing process, which increases the fluid pressure in the natural fracture and induces shear slip, resulting in casing deformation due to shear stress. Based on the understanding of the mechanism of casing deformation in shale oil wells, two targeted casing deformation prevention and control methods are proposed. First, temporary plugging was implemented during the hydraulic fracturing process when the fluid volume reached 1000 m3, and the pumping rate was reduced to below 16 m3/min to reduce the internal fluid pressure of the fractures and control fracture slip, thereby minimizing the risk of casing deformation. Second, hollow particles were added to the cement to enhance the consolidation effect of the cement sheath and mitigate casing deformation caused by fracture slip. Research indicates that a hollow particle content of 15% can meet the requirements for casing deformation control in Gulong shale oil. These research results can provide important references for the prediction and prevention of casing deformation risks in shale oil and similar unconventional reservoirs during hydraulic fracturing. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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21 pages, 10742 KiB  
Article
Failure Analysis of Casing in Shale Oil Wells under Multistage Fracturing Conditions
by Yisheng Mou, Han Zhao, Jian Cui, Zhe Wang, Fengqi Wei and Lihong Han
Processes 2023, 11(8), 2250; https://doi.org/10.3390/pr11082250 - 26 Jul 2023
Cited by 2 | Viewed by 1704
Abstract
During the multistage fracturing in shale oil and gas wells with tieback and liner, one of the major challenges is the wellbore temperature variation due to the high-rate fracturing. In such a case, the axial shrinkage trend of the casing string could be [...] Read more.
During the multistage fracturing in shale oil and gas wells with tieback and liner, one of the major challenges is the wellbore temperature variation due to the high-rate fracturing. In such a case, the axial shrinkage trend of the casing string could be caused due to the sudden drop in temperature, but the actual axial length of the casing string would not change due to the cement constraints. Therefore, this could lead to cementation damage between the casing and cement due to excessive load from the casing string. A wellbore seal that is out of control often leads to irreversible consequences, even well abandonment. In order to study the mechanism of casing deformation in shale oil and gas wells with tieback and liner quantitatively, in this paper, take LS1 well (a typical shale oil and gas well with tieback and liner, and casing deformation is caused) for example, the transient changes of temperature and pressure in the whole wellbore during multistage fracturing are studied. Moreover, the cementing strength test of the interface between casing and cement is also tested. Then, the testing results are carried out and extended to model the finite element (FE) model with the whole vertical section casing string with tieback and liner. The model is used to simulate the internal force changes under fracturing conditions with different stages of fracturing. Meanwhile, the casing deformation mechanism in LS1 well is analyzed and studied in detail. Our simulation results indicated the failure process and mechanism of cementation between casing and cement in shale oil and gas wells with tieback and liner. Our work can provide a detailed theoretical reference and a basis for field application. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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13 pages, 4718 KiB  
Article
A Novel Inner Wall Coating-Insulated Oil Pipeline for Scale and Wax Prevention
by Jing Cao, Wenhai Ma, Weiming Huang, Zhanfei Su, Yunbo Zhu and Jianjun Wang
Processes 2023, 11(7), 1964; https://doi.org/10.3390/pr11071964 - 28 Jun 2023
Cited by 4 | Viewed by 1381
Abstract
During the production of deep oil and gas, scaling, waxing, hydrate ice plugging and other problems easily occur. To solve these problems, reducing the temperature loss of oil pipelines is a feasible method. In order to protect the outer wall coating from being [...] Read more.
During the production of deep oil and gas, scaling, waxing, hydrate ice plugging and other problems easily occur. To solve these problems, reducing the temperature loss of oil pipelines is a feasible method. In order to protect the outer wall coating from being damaged and losing its thermal insulation performance, this paper proposes a developed technology for a novel inner wall coating-insulated oil pipeline. A new temperature-resistant and heat-insulating material aerogel was optimized and developed, and it has an extremely low thermal conductivity of less than 0.055 W/m·K. The influence of different coating processes on the thermal insulation coefficient was analyzed, and a novel inner wall coating-insulated oil pipeline was developed. A testing and evaluation platform for its thermal insulation effect was built, and a finite element model was established to analyze the temperature field distribution. When the thickness of the inner coating was 0.5 mm, the thermal insulation effect of the new oil pipeline improved by about 29%. This technology could be widely used in the production of deep oil and gas, high salinity oil and water reservoirs, thin oil reservoirs, etc., to alleviate scaling and waxing phenomena. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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13 pages, 8850 KiB  
Article
Failure Analysis of the Crack and Leakage of a Crude Oil Pipeline under CO2-Steam Flooding
by Chengli Song, Yuanpeng Li, Fan Wu, Jinheng Luo, Lifeng Li and Guangshan Li
Processes 2023, 11(5), 1567; https://doi.org/10.3390/pr11051567 - 21 May 2023
Cited by 4 | Viewed by 2106
Abstract
This paper presents the failure analysis of the crack and leakage accident of a crude oil pipeline under CO2-steam flooding in the western oilfield of China. To analyze the failure behavior and cause, different testing, including nondestructive testing, chemical composition analysis, [...] Read more.
This paper presents the failure analysis of the crack and leakage accident of a crude oil pipeline under CO2-steam flooding in the western oilfield of China. To analyze the failure behavior and cause, different testing, including nondestructive testing, chemical composition analysis, tensile property testing, metallographic analysis, and microanalysis of fracture and chloride stress corrosion cracking (SCC) testing, are applied in the present study. The obtained results showed that the pipeline under the insulation layer of high humidity, high oxygen content, and high Cl− environment occurred pit corrosion, and the stress concentration area at the bottom of the corrosion pit sprouted cracks. Besides, it is demonstrated that the cracks were much branched, mostly through the crystal, and the fracture showed brittle, which is consistent with the typical characteristics of chloride SCC. Meanwhile, the insufficient Ni content of the pipeline material promoted the process of chloride SCC, and the high-temperature working conditions also aggravated the rate of chloride SCC. In addition, efficient precautions were provided to avoid fracture. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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18 pages, 7510 KiB  
Article
Experimental Study on Downhole Acoustic Wave Propagation Characteristics in Curved Drill String
by Qing Wang, Chenguang Bi, Jiawei Zhang, Haige Wang and Zhichuan Guan
Processes 2023, 11(5), 1525; https://doi.org/10.3390/pr11051525 - 17 May 2023
Cited by 1 | Viewed by 1455
Abstract
Aiming at the problem of the unclear sound wave attenuation in the signal transmission of the load-bearing drill string, an experimental device for the sound wave propagation characteristics in the curved drill string was set up. The influence of the drill string structure [...] Read more.
Aiming at the problem of the unclear sound wave attenuation in the signal transmission of the load-bearing drill string, an experimental device for the sound wave propagation characteristics in the curved drill string was set up. The influence of the drill string structure and acoustic excitation parameters on the sound propagation characteristics in the drill string under different loads is different. The results show that the curvature of the drill string has an influence on the propagation of the sound wave in the drill string, and its rule is related to the curvature of the drill string and the frequency of the sound wave. The pulse repetition rate, excitation voltage, and pulse width only affect the passband amplitude, and the effect is significantly greater than the curvature of the drill string. The main influencing factor of its sound transmission characteristics is the degree of drill string curvature. The low-frequency signal should be preferentially selected as the carrier of downhole information transmission after considering the influence of drill string bending on acoustic transmission. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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17 pages, 2553 KiB  
Article
A Risk-Data-Based Human Reliability Analysis for Chemical Experiments with Hazardous Processes
by Renyou Zhang, Jun Ge, Jinchao Zhang, Huanhuan Cui, Qinhao Zhang and Zexing Zhang
Processes 2023, 11(5), 1484; https://doi.org/10.3390/pr11051484 - 13 May 2023
Cited by 3 | Viewed by 1564
Abstract
In recent years, chemical experiment accidents have frequently occurred, resulting in injuries and fatalities among researchers. It is crucial to address this issue to improve laboratory safety. Based on many publications, it is clear that human error makes a major contribution to many [...] Read more.
In recent years, chemical experiment accidents have frequently occurred, resulting in injuries and fatalities among researchers. It is crucial to address this issue to improve laboratory safety. Based on many publications, it is clear that human error makes a major contribution to many laboratory accidents which contain hazardous processes. However, there is limited research focusing on human error in laboratory safety, and there is also a lack of effective measures to assess Human Error Probability (HEP) for experimental process safety. Therefore, we propose an improved Cognitive Reliability and Error Analysis Method (CREAM) which is based on risk data to assess the HEP during hazardous processes in chemical experiments. The proposed method adjusts nine Common Performance Conditions (CPCs) in conventional CREAM to make them suitable to describe chemical experiments. Then, in contrast to the traditional approach, this study uses the definition of risk as the support to collect CPC data from the perspectives of possibility and severity, so as to improve the rationality of the data and decrease the subjectivity of expert judgment. Afterwards, the weight value of each CPC is calculated through Gray Relation Analysis (GRA) based on the collected risk data of each CPC. Meanwhile, the collected risk data are used to determine the fuzzy degrees of each CPC, the activated fuzzy If-Then rules, and the corresponding rule weights. Finally, the CPCs’ membership degrees, the CPCs’ weights, and If-Then rule weights are integrated together to acquire the HEP by defuzzification. In short, the proposed method changes the CPCs to ensure they are suitable, and then it innovatively uses risk data as the source to directly and indirectly determine the CPC’s fuzzy degree, the CPC’s importance weight, and the If-Then rule weight by fuzzy theory and GRA for collecting final HEP results. This method was tested on a selected chemical experiment, “preparation of active ferrous sulfide”, which contains hazardous processes. Through the proposed method, the HEP of each procedure in the selected risky chemical experiment could be determined, and among the procedures, the highest HEP was 1.51 × 10−3. In addition, with the HEP results, several subtasks with a high risk of human error could be identified. The results matched the real situations. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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16 pages, 1470 KiB  
Article
Frequent Alarm Pattern Mining of Industrial Alarm Flood Sequences by an Improved PrefixSpan Algorithm
by Songbai Yang, Tianxing Zhang, Yingchun Zhai, Kaifa Wang, Guoxi Zhao, Yuanfei Tu and Li Cheng
Processes 2023, 11(4), 1169; https://doi.org/10.3390/pr11041169 - 11 Apr 2023
Viewed by 1675
Abstract
Alarm systems are essential to the process safety and efficiency of complex industrial facilities. However, with the increasing size of plants and the growing complexity of industrial processes, alarm flooding is becoming a serious problem and posing challenges to alarm systems. Extracting alarm [...] Read more.
Alarm systems are essential to the process safety and efficiency of complex industrial facilities. However, with the increasing size of plants and the growing complexity of industrial processes, alarm flooding is becoming a serious problem and posing challenges to alarm systems. Extracting alarm patterns from an alarm flood database can assist with an alarm root cause analysis, decision support, and the configuration of an alarm suppression model. However, due to the large size of the alarm database and the problem of sequence ambiguity in the alarm sequence, existing algorithms suffer from excessive computational overhead, incomplete alarm patterns, and redundant outputs. In order to solve these problems, we propose an alarm pattern extraction method based on the improved PrefixSpan algorithm. Firstly, a priority-based pre-matching strategy is proposed to cluster similar sequences in advance. Secondly, we improved PrefixSpan by considering timestamps to tolerate short-term order ambiguity in alarm flood sequences. Thirdly, an alarm pattern compression method is proposed for the further distillation of pattern information in order to output representative alarm patterns. Finally, we evaluated the effectiveness and applicability of the proposed method by using an alarm flood database from a real diesel hydrogenation unit. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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19 pages, 9517 KiB  
Article
Microstructure, Wear Resistance and Corrosion Performance of Inconel 625 Layer Fabricated by Laser/Ultra-High Frequency (UHF) Induction Hybrid Deposition
by Rui Sun, Yuhang Qiao, Xinhong Li, Yongjun Shi and Xiaogang Wang
Processes 2023, 11(4), 1118; https://doi.org/10.3390/pr11041118 - 5 Apr 2023
Cited by 3 | Viewed by 1401
Abstract
In order to avoid microstructure degradation caused by low frequency induction heat in laser-induction hybrid deposition, this paper proposes a laser/ultra-high frequency (UHF) induction hybrid deposition method. Microstructure observation is carried out to reveal the effect of UHF induction heat on the microstructure [...] Read more.
In order to avoid microstructure degradation caused by low frequency induction heat in laser-induction hybrid deposition, this paper proposes a laser/ultra-high frequency (UHF) induction hybrid deposition method. Microstructure observation is carried out to reveal the effect of UHF induction heat on the microstructure of the deposited layer. Results indicate that the laser-UHF induction hybrid deposited layer, under a current density of 1.14 × 108 A/m2, exhibits a finer microstructure and fewer Laves phases than that of the laser deposited layer. As the current density increases from 1.01 × 108 A/m2 to 1.14 × 108 A/m2, the microstructure of the laser-UHF induction hybrid deposited layer is significantly refined; however, as the current density further increases, the microstructure is only slightly further refined, since the enhanced thermal effect, along with the increasing current density, may help grain growth. Wear test demonstrates that the laser-UHF induction hybrid deposited layer obtained with a current density of 1.40 × 108 A/m2 has the lowest average friction coefficient of 0.375 and the lowest wear rate of 15.53 × 10−5 mm3/N·m, indicating a better wear resistance. Corrosion resistance is also evaluated by electrochemical corrosion test. Results indicate that the addition of UHF induction heat improves the corrosion resistance of the deposited layer. Owing to the high ohm resistance of the passive film, the deposited layer fabricated with a current density of 1.01 × 108 A/m2 exhibits the best corrosion resistance. Based on the analysis of wear and corrosion performance, the current density of 1.40 × 108 A/m2 is an optimal parameter for a laser-UHF induction hybrid deposited Inconel 625 layer. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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17 pages, 4113 KiB  
Article
Analytical Model of Hydraulic Fracturing for Low Permeability Hot Dry Rock Reservoirs and DEM Simulation Base on Fluid-Solid Coupling
by Heng Fan, Peihang Liu, Yating Zhao, Shangyu Yang and Xinbo Zhao
Processes 2023, 11(4), 976; https://doi.org/10.3390/pr11040976 - 23 Mar 2023
Viewed by 1773
Abstract
The formation of a rich underground-seam network is the key problem in the development of low-permeability hot dry rock (HDR) resources. Considering the lack of macroscopic continuum theory to study hydraulic fracturing having preset fracture-interface element, the particle-flow method of micro-mechanical discrete-element theory [...] Read more.
The formation of a rich underground-seam network is the key problem in the development of low-permeability hot dry rock (HDR) resources. Considering the lack of macroscopic continuum theory to study hydraulic fracturing having preset fracture-interface element, the particle-flow method of micro-mechanical discrete-element theory is introduced to simulate the mechanical behavior of hydraulic fracturing for HDR low permeability reservoirs. The reservoir is simulated as a round particle; the fracturing fluid movement is described by the seepage field equation, and rock movement is described by the displacement field equation. Finally, the particle-flow numerical model of hydraulic fracturing for HDR low permeability reservoirs is established under the condition of fluid-solid coupling: the model contains two parts (rock and fracture). Based on the parallel-bond model, a definition of micro-fractures of hydraulic fracturing is given. The relation between the fracturing effect and influence parameters is discussed. The results show that the fracture-initiation pressure is proportional to the magnitude of minimum horizontal stress, particle normal-contact stiffness, and particle normal- and tangential-connection strengths; the pressure is also independent of maximal horizontal stress and tangential contact stiffness. At the same time, the formation temperature of dry hot rock will reduce the strength of the rock, so particle-flow numerical models of hydraulic fracturing in different temperatures are discussed. Results show that fracture length and width show a trend of increase before decrease with the increase of injection pressure, an inverse relationship with minimums horizontal principal stress, and a positive relationship with HDR reservoir permeability. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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12 pages, 2462 KiB  
Article
A Transfer Learning Methodology for Recognizing Unsafe Behavior during Lifting Operations in a Chemical Plant
by Hua Li, Xicheng Xue, Yanbin Wang, Lizhou Wu and Xinhong Li
Processes 2023, 11(3), 971; https://doi.org/10.3390/pr11030971 - 22 Mar 2023
Viewed by 1589
Abstract
Large lifting equipment is used regularly in the maintenance operations of chemical plant installations, where safety controls must be carried out to ensure the safety of lifting operations. This paper presents a convolutional neural network (CNN) methodology, based on the PyTorch framework, to [...] Read more.
Large lifting equipment is used regularly in the maintenance operations of chemical plant installations, where safety controls must be carried out to ensure the safety of lifting operations. This paper presents a convolutional neural network (CNN) methodology, based on the PyTorch framework, to identify unsafe behavior among lifting operation drivers, specifically, by collecting 22,352 images of equipment lifting operations over a certain time period in a chemical plant. The lifting drivers’ behavior was divided into eight categories, and a ResNet50 network model was selected to identify the drivers’ behavior in the pictures. The results show that the proposed ResNet50 network model based on transfer learning achieves a 99.6% accuracy rate, a 99% recall rate and a 99% F1 value for the expected behaviors of eight lifting operation drivers. This knowledge regarding unsafe behavior in the chemical industry provides a new perspective for preventing safety accidents caused by the dangerous behaviors of lifting operation drivers. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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20 pages, 2338 KiB  
Article
Risk Assessment of Concentralized Distribution Logistics in Cruise-Building Imported Materials
by Zhimin Cui, Haiyan Wang and Jing Xu
Processes 2023, 11(3), 859; https://doi.org/10.3390/pr11030859 - 13 Mar 2023
Cited by 2 | Viewed by 1663
Abstract
The concentralized distribution logistics in cruise-building imported materials (CDL-CIMs) constitute a complex process that requires a high degree of coordination between the multi-link and multi-participator. Delayed delivery, materials damaged, and cost overruns occur because of increasing uncertainties and risks, which may cause disjointedness [...] Read more.
The concentralized distribution logistics in cruise-building imported materials (CDL-CIMs) constitute a complex process that requires a high degree of coordination between the multi-link and multi-participator. Delayed delivery, materials damaged, and cost overruns occur because of increasing uncertainties and risks, which may cause disjointedness in cruise construction planning. Therefore, it is essential to conduct a risk assessment of the CDL-CIMs to examine their adverse impacts on cruise construction. Drawing on the advantages of the failure modes and effects analysis (FMEA) method in risk assessment, an effective and efficient model is developed using a novel hybrid method in this paper, namely the rule-based Bayesian network (RBN) and utility function. The approach has its superiorities in dealing with vague and uncertainty risk information. In addition, the risk parameters from multiple perspectives concerning “occurrence likelihood”, “detection”, “delayed schedule”, “damaged quality”, and “additional cost” facilitate the understanding of the risk characteristics of the CDL-CIMs. The applicability and robustness of the proposed method are demonstrated by an empirical study for the first cruise constructed in China. The results reveal that the highest-priority threats are the poor management for the actors in the logistics chain (MR1), human errors (MR5), limited storage ability and poor environment of warehouse (ER2), and ignorance of good handling practices during the operation of loading and unloading (OR2). The conclusion can provide insight into the implementation of risk response strategies for cruise-building logistics management in China and other countries. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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14 pages, 8959 KiB  
Article
A Casing Deformation Prediction Model Considering the Properties of Cement
by Bo Zeng, Xiaojin Zhou, Jing Cao, Feng Zhou, Yao Wang, Yezhong Wang, Yi Song, Junjie Hu and Yurou Du
Processes 2023, 11(3), 695; https://doi.org/10.3390/pr11030695 - 24 Feb 2023
Cited by 4 | Viewed by 1752
Abstract
A large amount of casing deformation has occurred in shale gas wells during the complex fracturing process, which affects the fracturing construction and single well production. Based on the statistical analysis of casing deformation wells and caliper logging interpretation, the main mechanism of [...] Read more.
A large amount of casing deformation has occurred in shale gas wells during the complex fracturing process, which affects the fracturing construction and single well production. Based on the statistical analysis of casing deformation wells and caliper logging interpretation, the main mechanism of casing deformation of shale gas wells is revealed as formation slip. By comprehensively considering the rotating speed under casing running condition, the cement solidification heat release under cementing condition, and the fracturing fluid temperature drop under fracturing condition, the safe service margin of the casing is large. Moreover, simply increasing the casing steel grade and wall thickness has no obvious effect on casing deformation prevention, so full wellbore casing deformation prevention measures should be considered. By using the method of unconventional oil and gas well casing string simulation test and numerical simulation, the mechanical response of wellbore and the mechanism of bridge plug resistance are analyzed. By analyzing the influence of elastic modulus and wall thickness of cement on the casing minimum drift diameter after shear deformation, an analytical model of the minimum drift diameter of shale gas casing under the effect of fracture slip is established and verified, which provides technical support for parameter selection of cement and measures to prevent casing deformation. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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24 pages, 8541 KiB  
Article
Dynamic Analysis of the Lifting Arm System in the Integrated Offshore Platform Decommissioning Equipment in Complicated Sea States
by Wensheng Xiao, Changjiang Li, Lianghuan Fan, Quan Li and Liping Tan
Processes 2023, 11(2), 645; https://doi.org/10.3390/pr11020645 - 20 Feb 2023
Cited by 2 | Viewed by 2133
Abstract
With the further exploitation of offshore resources, there are more and more offshore oil and gas fields which cannot meet the production capacity requirements. So, it becomes extremely urgent to pay attention to the decommissioning of the exploitation equipment in abandoned offshore fields. [...] Read more.
With the further exploitation of offshore resources, there are more and more offshore oil and gas fields which cannot meet the production capacity requirements. So, it becomes extremely urgent to pay attention to the decommissioning of the exploitation equipment in abandoned offshore fields. A new decommissioning solution is offered by the double-ship integrated offshore platform decommissioning equipment comes. However, as the equipment will inevitably bear the combined actions of various dynamic and static loads during operation, the strength and stability of the overall unit and the connections between different modules will be greatly challenged by the complex ocean. Firstly, the dynamic characteristics of the integrated decommissioning system are analyzed in this paper. Mathematical modeling of the lifting arm system is established based on the unit characteristics matrix, and a dynamic equation of the flexible lifting arm unit and system is developed based on Lagrange’s equation and solved through numerical calculation. Secondly, modal analysis and transient analysis of the lifting arm in specific working conditions are performed according to the prototype parameters of the designed decommissioning system. Finally, according to the principle of similitude, a hydrodynamic experiment method is proposed with an integrated decommissioning multi-dimensional vibration test bench. The decommissioning system model test bench is designed and built to perform the dynamic response test, and this paper compares the test results and the simulation results for verification. The comparison verifies that the theoretical analysis and the tests prove each other valid and the results are accurate, meaning this work provides a powerful theoretical reference and offers effective research methods for future studies on super-large-scale integrated decommissioning equipment. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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12 pages, 2974 KiB  
Article
Density Functional Theory Study of the Electronic Structures of Galena
by Jianxiong Kang, Yanni An, Jiwei Xue, Xiao Ma, Jiuzhou Li, Fanfan Chen, Sen Wang, He Wan, Chonghui Zhang and Xianzhong Bu
Processes 2023, 11(2), 619; https://doi.org/10.3390/pr11020619 - 17 Feb 2023
Cited by 6 | Viewed by 1915
Abstract
In this study, the electronic structure of the galena surface was investigated using the first-principle calculation. The results of band structure, density of states, Mulliken population distribution, and frontier orbital analysis showed that galena was the p-type semiconductor of the direct band gap. [...] Read more.
In this study, the electronic structure of the galena surface was investigated using the first-principle calculation. The results of band structure, density of states, Mulliken population distribution, and frontier orbital analysis showed that galena was the p-type semiconductor of the direct band gap. During the formation of galena crystals, the 3p orbital of the S and the 6p orbital of the Pb played a primary role. Additionally, S atoms in galena quickly lose electrons and are oxidized, while Pb readily reacts with anions. The results of surface structure and electronic properties, such as surface relaxation, surface state energy levels, electronic density of states, and atomic charge distribution showed that the electronics in the 6p orbital of the Pb are transferred to the 3p orbital of the S in galena crystal. They caused the change of atomic valence states in lattice surfaces. The total electron number of the outermost surface layer was also higher than the bulk, giving the galena surface the properties of electron enrichment. This research is of great significance for developing new galena flotation reagents and for further in-depth exploration of the adsorption of reagents on the galena surface. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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18 pages, 2230 KiB  
Article
Assessment of the Explosion Accident Risk in Non-Coal Mining by Hasse Diagram Technique
by Xiaobin Dong, Zhen Yang, Li Guo and Yuan Gao
Processes 2023, 11(2), 582; https://doi.org/10.3390/pr11020582 - 14 Feb 2023
Cited by 2 | Viewed by 1576
Abstract
The aim of is paper is to address the problem of identifying critical factors in the analysis of non-coal mine explosion accidents as well as to improve the rationality and accuracy of the risk analysis results. Hence, we developed a risk identification method [...] Read more.
The aim of is paper is to address the problem of identifying critical factors in the analysis of non-coal mine explosion accidents as well as to improve the rationality and accuracy of the risk analysis results. Hence, we developed a risk identification method for non-coal mine explosion accidents, combining the Systems-Theoretic Accident Model and Process (STAMP) and the Rank-order Centroid (ROC) method based on the Poset decision-making theory. The proposed method was applied to identify risk in engineering cases. Findings showed that four main dangerous events (out of twelve identified ones) were the primary culprits of related accidents, which were the events “Blasters without licenses and illegal operation” at the basic level, the event of “the confusion about the safety management system of non-coal mine companies” at the control level, and the event of “the failure about the emergency management departments” and “public security departments” at the supervision level. The approximate values of the average rank of the four events are 11.56, 10.4, 4.33, 4.33. The results of risk identification of non-coal mine explosion accidents based on Poset were consistent with the results obtained by the method used in the case study. This study extends the methods for identifying risks of non-coal mine explosion accidents and facilitates the formulation of effective preventive measures. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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16 pages, 7004 KiB  
Article
Research on the Effect of Shale Core Mechanical Behavior on Casing Deformation
by Dongfeng Li, Zhanyou He, Rui Wang, Le Zhang, Heng Fan, Hailiang Nie and Zixiong Mo
Processes 2023, 11(1), 274; https://doi.org/10.3390/pr11010274 - 14 Jan 2023
Cited by 1 | Viewed by 1424
Abstract
As an unconventional, high-quality, efficient, and clean low-carbon energy, shale gas has become a new bright spot in the exploration and development of global oil and gas resources. However, with the increasing development of shale gas in recent years, the anisotropic load of [...] Read more.
As an unconventional, high-quality, efficient, and clean low-carbon energy, shale gas has become a new bright spot in the exploration and development of global oil and gas resources. However, with the increasing development of shale gas in recent years, the anisotropic load of the shale reservoir during the mining process has caused the casing to be deformed or damaged more and more seriously. In this paper, the mechanical behavior of shale core shear, triaxial and radial compression are studied using rock true compression tests, shear tests and nuclear magnetic resonance (NMR) technology. The process of macroscopic and microscopic changes of shale fractures during the tests were analyzed to predict the effect of the fracture-state changes and stress-state changes of different shale reservoirs on the casing deformation. The results show that after the shale core is damaged, the overall pore structure changes, resulting in the decrease or increase in shale porosity. During the process of triaxial pressurization, as the pressure continues to increase, there will be a critical pressure value from elastic deformation to plastic deformation. When the pressure value exceeds the critical pressure value, the shale reservoir will have strong stress sensitivity, which can easily cause wellbore collapse. The research results have important guiding significance for determining the casing deformation under shale reservoir load and preventing casing deformation failure. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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12 pages, 2319 KiB  
Article
Scenario-Driven Methodology for Cascading Disasters Risk Assessment of Earthquake on Chemical Industrial Park
by Li Guo, Junming Liang, Tao Chen, Yuan Gao and Zhen Yang
Processes 2023, 11(1), 32; https://doi.org/10.3390/pr11010032 - 23 Dec 2022
Cited by 5 | Viewed by 2789
Abstract
With the increase in industrial accidents induced by natural disasters, the study of earthquake risk assessment has been widely considered by scholars. However, the cascade evolution of Natech (natural–technological) disasters has not been thoroughly studied, especially in chemical parks with complex technological processes. [...] Read more.
With the increase in industrial accidents induced by natural disasters, the study of earthquake risk assessment has been widely considered by scholars. However, the cascade evolution of Natech (natural–technological) disasters has not been thoroughly studied, especially in chemical parks with complex technological processes. From the perspective of scenario deduction, combined with cross-impact analysis and a damping interpretation structural model, this paper analyzes the evolution process of cascade disaster in a chemical industrial park after the Wenchuan earthquake. At the same time, a visual network risk assessment model is constructed to identify the impact of earthquake cascade disasters on the park. The simulation results show that the scenario-driven risk assessment method proposed in this paper can directly reflect the coupling relationship and propagation path among the derived events and realize dynamic, intuitive and structured disaster expression to deal with the earthquake Natech (natural–technological) disaster scenario effectively and quickly. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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16 pages, 6112 KiB  
Article
The Mechanism of Casing Deformation before Hydraulic Fracturing and Mitigation Measures in Shale Gas Horizontal Wells
by Yisheng Mou, Jian Cui, Jianjun Wu, Fengqi Wei, Ming Tian and Lihong Han
Processes 2022, 10(12), 2612; https://doi.org/10.3390/pr10122612 - 6 Dec 2022
Cited by 5 | Viewed by 1943
Abstract
During the development of shale gas, one of the major challenges is the casing deformation (CD) in the horizontal section due to the geological activity. Recently, the casing deformation before hydraulic fracturing (CDBF) occurred in multiple shale gas wells in L block in [...] Read more.
During the development of shale gas, one of the major challenges is the casing deformation (CD) in the horizontal section due to the geological activity. Recently, the casing deformation before hydraulic fracturing (CDBF) occurred in multiple shale gas wells in L block in China. In this paper, based on the theory of tubular mechanics, the relationship between casing buckling and CDBF caused by casing running in is analyzed qualitatively and quantitatively. It is found that the buckling deformation caused by running the casing string process is not sufficient to prevent the tool (Φ99 mm bridge plug). On the other hand, the mechanism of CDBF is systematically analyzed based on the actual field data and finite element (FE) method. In order to analyze the CDBF mechanism, the comparison between the actual casing trajectory and the reservoir rock (S#1, S#2, S#3 and M#1) in horizontal section in H2 platform is carried out, and the preliminary CDBF mechanism is proposed. Then, two groups of FE models are established to reduce the CD process to verify the preliminary mechanism. It is found that the numerical simulation results (high stress section length from FE model) are in good agreement with the actual CD logging results. Based on the analytical results, the corresponding mitigation measures are proposed based on the analysis of the CDBF mechanism. Our work could offer a detailed theoretical basis and reference of CDBF for shale gas well application. Full article
(This article belongs to the Special Issue Risk Assessment and Reliability Engineering of Process Operations)
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