The transportation of oil is an important aspect of chemical process safety. In the accidental leakage of oil and related products, the flame spread occurs occasionally when the liquid fuel is activated by a pilot flame. In the potential application of fire prevention, a step obstacle placed above the oil ditch may effectively hinder the flame spread. The effectiveness of the usage of a step obstacle depends on the size of the obstacle and the heat exchange mechanism. Therefore, the investigation of inhibition behavior and heat transfer of liquid flame spread with gas step obstacle is performed. The hot fluids flow inside the channel to carry out the convection heat to the initial cold oils on the opposite of the gas step obstacle. The flame configuration is blocked behind the step obstacle. The flame spread behaviors including flame morphology, inhibition time, and air entrainment are characterized and analyzed. The heat flows of flame radiation and liquid‐phase convection are theoretically calculated, and the primary heat transfer mechanism is determined. This work is helpful for the development of fire safety technology and the establishment of standard specifications for oil transportation.
{"title":"Inhibition behavior and heat transfer of flame spread over liquid fuel with the influence of a step obstacle in the gas phase","authors":"Shenlin Yang, Peiyuan Hu, Ranran Li, Manhou Li, Quanmin Xie, Jingchuan Li","doi":"10.1002/prs.12564","DOIUrl":"https://doi.org/10.1002/prs.12564","url":null,"abstract":"The transportation of oil is an important aspect of chemical process safety. In the accidental leakage of oil and related products, the flame spread occurs occasionally when the liquid fuel is activated by a pilot flame. In the potential application of fire prevention, a step obstacle placed above the oil ditch may effectively hinder the flame spread. The effectiveness of the usage of a step obstacle depends on the size of the obstacle and the heat exchange mechanism. Therefore, the investigation of inhibition behavior and heat transfer of liquid flame spread with gas step obstacle is performed. The hot fluids flow inside the channel to carry out the convection heat to the initial cold oils on the opposite of the gas step obstacle. The flame configuration is blocked behind the step obstacle. The flame spread behaviors including flame morphology, inhibition time, and air entrainment are characterized and analyzed. The heat flows of flame radiation and liquid‐phase convection are theoretically calculated, and the primary heat transfer mechanism is determined. This work is helpful for the development of fire safety technology and the establishment of standard specifications for oil transportation.","PeriodicalId":20680,"journal":{"name":"Process Safety Progress","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138945096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yingquan Qi, Li Ding, Yong Pan, Jingran Liu, Supan Wang
The study of the explosion parameters of ethanol–air mixture at high pressure and temperature is essential for the safe production of ethanol. However, the explosion characteristics of ethanol vapor at various pressures and temperatures are limited. The mechanism at the flammability limits of ethanol has not been clarified, and the corresponding prediction model is also lacking. In this study, chemical kinetics and machine learning are used to study the mechanism of ethanol explosion and build predictive models, respectively. Our findings show that an increase in the initial pressure has a more pronounced influence on the explosion pressure (Pex) and pressure rise rate (dp/dt) than an increase of temperature. The variation trend of the upper flammability limit (UFL) of ethanol is related to the different effects of temperature and pressure on OH radicals. H + O2<>OH + O and HO2 + CH3<>OH + CH3O had the greatest effect on the generation of OH radicals. The quantitative relationship between the H, O, and OH radicals and UFL was constructed by machine learning, providing a new research perspective for the prediction of the UFL of an inflammable fuel under different pressures and temperatures. The results of the study will provide theoretical and practical guidance for the prevention and control of explosions in the ethanol production process.
{"title":"Study of ethanol vapor explosion and prediction based on chemical kinetics under high temperature and pressure","authors":"Yingquan Qi, Li Ding, Yong Pan, Jingran Liu, Supan Wang","doi":"10.1002/prs.12566","DOIUrl":"https://doi.org/10.1002/prs.12566","url":null,"abstract":"The study of the explosion parameters of ethanol–air mixture at high pressure and temperature is essential for the safe production of ethanol. However, the explosion characteristics of ethanol vapor at various pressures and temperatures are limited. The mechanism at the flammability limits of ethanol has not been clarified, and the corresponding prediction model is also lacking. In this study, chemical kinetics and machine learning are used to study the mechanism of ethanol explosion and build predictive models, respectively. Our findings show that an increase in the initial pressure has a more pronounced influence on the explosion pressure (<i>P</i><sub>ex</sub>) and pressure rise rate (d<i>p</i>/d<i>t</i>) than an increase of temperature. The variation trend of the upper flammability limit (UFL) of ethanol is related to the different effects of temperature and pressure on OH radicals. H + O<sub>2</sub><>OH + O and HO<sub>2</sub> + CH<sub>3</sub><>OH + CH<sub>3</sub>O had the greatest effect on the generation of OH radicals. The quantitative relationship between the H, O, and OH radicals and UFL was constructed by machine learning, providing a new research perspective for the prediction of the UFL of an inflammable fuel under different pressures and temperatures. The results of the study will provide theoretical and practical guidance for the prevention and control of explosions in the ethanol production process.","PeriodicalId":20680,"journal":{"name":"Process Safety Progress","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138823736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tarek Bengherbia, Faisal A. Syed, Jenny Chew, Fathullah A. Khalid, Alex F. T. Goh, Kenza Chraibi, Mohammed Zainal Abdeen
The accurate prediction of gas dispersion and the potential consequences of gas explosions hold a pivotal role in the assessment of explosion design loads for oil and gas processing facilities. This often involves the use of computational fluid dynamics (CFD) simulations, a widely adopted practice in the field. The extent of CFD simulations required depends on the specific characteristics and size of the facility. In many cases, a substantial number of simulations, often in the thousands, are needed to comprehensively assess the potential outcomes in the event of a hydrocarbon loss of containment. These simulations account for the complex three-dimensional nature of the facility, the surrounding environmental conditions, and the properties of the leaking hydrocarbon fluids. Although unquestionably invaluable, CFD simulations impose significant temporal constraints upon their execution and necessitate the allocation of substantial efforts and Central Processing Unit (CPU) time. In this paper we develop a neural model tailored specifically for the analysis of CFD gas dispersion and gas explosion scenarios. This model leverages the capabilities of machine learning algorithms to expedite the execution of these complex studies. The proposed neural network model has the advantage of being able to handle a wide range of scenarios in a fraction of time it takes to perform the CFD simulations, making it particularly useful for large-scale processes facilities. The accuracy of the predictions is remarkably high, providing a high level of confidence in the predictions of the flammable gas clouds sizes across various scenarios, as well as the resulting explosion overpressures.
{"title":"Application of machine learning methods for process safety assessments","authors":"Tarek Bengherbia, Faisal A. Syed, Jenny Chew, Fathullah A. Khalid, Alex F. T. Goh, Kenza Chraibi, Mohammed Zainal Abdeen","doi":"10.1002/prs.12562","DOIUrl":"https://doi.org/10.1002/prs.12562","url":null,"abstract":"The accurate prediction of gas dispersion and the potential consequences of gas explosions hold a pivotal role in the assessment of explosion design loads for oil and gas processing facilities. This often involves the use of computational fluid dynamics (CFD) simulations, a widely adopted practice in the field. The extent of CFD simulations required depends on the specific characteristics and size of the facility. In many cases, a substantial number of simulations, often in the thousands, are needed to comprehensively assess the potential outcomes in the event of a hydrocarbon loss of containment. These simulations account for the complex three-dimensional nature of the facility, the surrounding environmental conditions, and the properties of the leaking hydrocarbon fluids. Although unquestionably invaluable, CFD simulations impose significant temporal constraints upon their execution and necessitate the allocation of substantial efforts and Central Processing Unit (CPU) time. In this paper we develop a neural model tailored specifically for the analysis of CFD gas dispersion and gas explosion scenarios. This model leverages the capabilities of machine learning algorithms to expedite the execution of these complex studies. The proposed neural network model has the advantage of being able to handle a wide range of scenarios in a fraction of time it takes to perform the CFD simulations, making it particularly useful for large-scale processes facilities. The accuracy of the predictions is remarkably high, providing a high level of confidence in the predictions of the flammable gas clouds sizes across various scenarios, as well as the resulting explosion overpressures.","PeriodicalId":20680,"journal":{"name":"Process Safety Progress","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138823720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maxwell Judd Lawrence, Rafeqah Raslan, Nur Shahidah Ab Aziz
Insect repellents are one of the most effective ways to prevent the spread of diseases such as dengue, malaria, and yellow fever. However, most insect repellents contain ingredients that pose a significant risk to consumers. Therefore, this research aims to design a safer and less harmful insect-repellent formulation based on the formulated product design methodology. Computer-aided molecular design (CAMD) methodology was employed to design an insect-repellent solvent that exhibits minimum safety and health risks. The safety and health hazards of all the selected ingredients were then assessed using an inherent safety and health index known as the Product Ingredient Safety and Health Index (PISHI). As a result, the proposed insect-repellent formulation with minimum safety and health risks may consist of picaridin, 1,5-pentanediol, and linalool. This research contributed to an inherently safer formulation design, where the identification and elimination of hazardous ingredients has been done at the early design stage. The safer and less harmful ingredients used in the insect-repellent formulation may reduce the significant risk to consumers.
{"title":"Computer-aided design of insect-repellent formulation with inherent safety assessment","authors":"Maxwell Judd Lawrence, Rafeqah Raslan, Nur Shahidah Ab Aziz","doi":"10.1002/prs.12568","DOIUrl":"https://doi.org/10.1002/prs.12568","url":null,"abstract":"Insect repellents are one of the most effective ways to prevent the spread of diseases such as dengue, malaria, and yellow fever. However, most insect repellents contain ingredients that pose a significant risk to consumers. Therefore, this research aims to design a safer and less harmful insect-repellent formulation based on the formulated product design methodology. Computer-aided molecular design (CAMD) methodology was employed to design an insect-repellent solvent that exhibits minimum safety and health risks. The safety and health hazards of all the selected ingredients were then assessed using an inherent safety and health index known as the Product Ingredient Safety and Health Index (PISHI). As a result, the proposed insect-repellent formulation with minimum safety and health risks may consist of picaridin, 1,5-pentanediol, and linalool. This research contributed to an inherently safer formulation design, where the identification and elimination of hazardous ingredients has been done at the early design stage. The safer and less harmful ingredients used in the insect-repellent formulation may reduce the significant risk to consumers.","PeriodicalId":20680,"journal":{"name":"Process Safety Progress","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138714712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
With the increase of Liquefied Natural Gas (LNG) fuel-powered vessels, LNG bunkering vessels have become an important development direction of LNG bunkering technology for its advantages. However, the LNG bunkering vessel operation risk assessment is relatively few. Formal Safety Assessment (FSA) is a novel structured and systematic risk analysis method for Marine engineering, through the data analysis based on probability theory, people can foresee the risk before the accident and take measures to reduce the risk and avoid heavy loss. In this paper, the LNG bunkering vessel operation process is divided into four subprocesses: the loading process, the navigation process, the bunkering process, and the anchoring process. The FSA method is used to identify and evaluate the risks in each process, judge the negligible risk, reasonable and feasible low risk, unacceptable risk, and put forward corresponding safe measures to provide safety guarantees for the operation of LNG bunkering vessels. Through the standardized assessment steps of FSA, a risk model for the LNG bunkering vessel operation process is established, and reasonable suggestions and measures that can effectively control the risk of the LNG bunkering vessel operation process are proposed, the research results of this paper can provide important technical guidance and reference value for the safe operation of LNG bunkering vessel.
{"title":"Risk assessment of LNG bunkering vessel operation based on formal safety assessment method","authors":"Yunlong Wang, Zhiqiang Cha, Guopeng Liang, Xin Zhang, Kai Li, Guan Guan","doi":"10.1002/prs.12561","DOIUrl":"https://doi.org/10.1002/prs.12561","url":null,"abstract":"With the increase of Liquefied Natural Gas (LNG) fuel-powered vessels, LNG bunkering vessels have become an important development direction of LNG bunkering technology for its advantages. However, the LNG bunkering vessel operation risk assessment is relatively few. Formal Safety Assessment (FSA) is a novel structured and systematic risk analysis method for Marine engineering, through the data analysis based on probability theory, people can foresee the risk before the accident and take measures to reduce the risk and avoid heavy loss. In this paper, the LNG bunkering vessel operation process is divided into four subprocesses: the loading process, the navigation process, the bunkering process, and the anchoring process. The FSA method is used to identify and evaluate the risks in each process, judge the negligible risk, reasonable and feasible low risk, unacceptable risk, and put forward corresponding safe measures to provide safety guarantees for the operation of LNG bunkering vessels. Through the standardized assessment steps of FSA, a risk model for the LNG bunkering vessel operation process is established, and reasonable suggestions and measures that can effectively control the risk of the LNG bunkering vessel operation process are proposed, the research results of this paper can provide important technical guidance and reference value for the safe operation of LNG bunkering vessel.","PeriodicalId":20680,"journal":{"name":"Process Safety Progress","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138568092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kim M-G, Lee HE, Yoon SJ, Kim JH, Moon K-W. A gas detector planning method that considers the area and zone based on the range of influence of chemicals with high vapor pressure. Process Saf Prog. 2023; 42(3):537–549. doi:10.1002/prs.12478