Process safety data management program based on HAZOP analysis and its application to an ethylene oxide/ethylene glycol plant

HAZOP analysis is a process hazard analysis method that has been widely applied both within and outside the chemical processing industries. This paper presents a design method for a process safety data management program for petrochemical plants based on HAZOP analysis and demonstrates the steps of application involved in building a process safety data management system for an ethylene oxide/ethylene glycol production plant. Firstly, the production data files and relevant documents of the plants should be classified and stored in the program database as reference documents and treatment schemes for coping with abnormal situations should be collected and summarized as guidance documents. Secondly, the HAZOP analysis method is employed to identify all the dangerous deviations possibly existing in the production process of the ethylene oxide/ethylene glycol plant. Then, the relationships among the deviations, the reference documents and the guidance documents should be considered and evaluated. Finally, each dangerous deviation will be given a corresponding reference document and guidance document. The reference documents and guidance documents stored in the expert system can be utilized to help operators solve the corresponding technical problems and cope with abnormal situations. The process safety data management program will contribute to the identification, analysis and resolution of operation problems. When an abnormal situation occurs, according to the deviations exhibited in the system, the necessary reference documents and guidance documents will be quickly consulted by the operators, and an appropriate decision will be made to address the abnormal situation. Therefore, by using the process safety data management program, plant security and human safety in the petrochemical industries will be improved.     

HAZOP结合What-if方法在某延迟焦化装置除焦中的应用

为克服传统危险与可操作性（HAZOP）定性分析方法在复杂操作、间歇作业等过程中使用的局限性,提出在传统HAZOP定性分析方法的基础上结合What-if（故障假设）方法,对人的不安全行为和操作规程不完备所导致的风险后果分析作出补充。详细说明其技术原理、工作流程等使用细节,系统阐述该方法与传统HAZOP定性分析方法的区别,并在某延迟焦化装置的除焦操作的风险分析中应用。经分析,识别出在“给水-泡焦”节点,有“操作规程错误”场景2项,“操作规程不具体”场景1项,不存在“操作人员未按操作规程执行”场景。研究结果表明:本文方法有效且具有较好效果,可以广泛应用于操作规程/作业指导书审查、作业过程隐患排查等方面,帮助企业开展操作层面的风险识别与管理,提升企业的生产安全水平。     

HAZOP – Local approach in the Mexican oil & gas industry

HAZOP (Hazard and Operability) studies began about 40 years ago, when the Process Industry and complexity of its operations start to massively grow in different parts of the world. HAZOP has been successfully applied in Process Systems hazard identification by operators, design engineers and consulting firms. Nevertheless, after a few decades since its first applications, HAZOP studies are not truly standard in worldwide industrial practice. It is common to find differences in its execution and results format. The aim of this paper is to show that in the Mexican case at National level in the oil and gas industry, there exist an explicit acceptance risk criteria, thus impacting the risk scenarios prioritizing process. Although HAZOP studies in the Mexican oil & gas industry, based on PEMEX corporate standard has precise acceptance criteria, it is not a significant difference in HAZOP applied elsewhere, but has the advantage of being fully transparent in terms of what a local industry is willing to accept as the level of risk acceptance criteria, also helps to gain an understanding of the degree of HAZOP applications in the Mexican oil & gas sector. Contrary to this in HAZOP ISO standard, risk acceptance criteria is not specified and it only mentions that HAZOP can consider scenarios ranking. The paper concludes indicating major implications of risk ranking in HAZOP, whether before or after safeguards identification.     

工艺过程危险有害因素辨识的研究

鉴于化工企业工艺过程的特殊性,笔者建议其危险、有害因素的辨识可以在直观经验分析法和系统安全分析法的基础上,结合危险和可操作性研究(HAZOP)的思想来进行辨识。笔者尝试性地给出了相关术语的说明、介绍辨识方法和操作程序,并分别从生产过程(包括化学反应、化工操作单元和物料输送)和工艺设备、装置角度,对其中的所包含的具体内容进行剖析,最后以电解过程举例说明,该方法可用于化工企业进行危险性因素辨识。     

Model-based HAZOP study of a real MTBE plant

Integration of a mathematical model approach with hazard and operability (HAZOP) analysis is presented in this contribution. The presented analysis is based on the mathematical modelling of a process unit, where both the steady-state analysis (including continuation and bifurcation analyses), and the dynamic simulation are used. The main benefit of this integration is the ability to perform a detail safety analysis for a relatively complicated process. Such an approach may dramatically decrease the possibility that several sources of hazard will be overlooked. Of course, the presented methodology may also seriously reduce the time necessary for the hazard identification process. In this paper, a methyl tertiary-butyl ether (MTBE) production unit was chosen to identify potential hazard and operational problems of a real process. This simplified case-study unit consists of two investigated types of equipment: a tubular fixed bed reactor and a reactive distillation column.     

在役柴油加氢装置HAZOP分析技术

柴油加氢装置属甲类火灾危险生产装置,为了保障其安全生产,实现事故早期预防,对其进行风险分析和安全评价势在必行.HAZOP分析方法是流程工业广泛使用的一种危险辨识和分析方法,具有较好的系统性和完备性.首先介绍了HAZOP分析方法的由来及应用情况,其次分析了在役装置HAZOP分析的难点,并提出了相应的建议,然后详述了在役装置HAZOP方法的分析流程.最后以中石油某石化公司在役柴油加氢装置为例进行了HAZOP分析,辨识出可能存在的安全隐患和潜在危险,对较高风险提出了必要的安全保护措施和合理的改进建议.结果表明,HAZOP分析是提高在役装置安全性的一种有效手段,其结果为装置安全管理提供了可靠的依据.     

HAZOP分析技术改进研究

通过HAZOP分析技术研究,提出针对性的3方面改进措施:开发HAZOP偏差专家库,并在开发的辅助分析软件中进行自动关联提示,弥补分析成员经验不足;基于专业化的计划安排与分工控制分析过程,提高分析工作效率;简化分析范围,并借助偏差库的帮助简化重复工作。对开展HAZOP分析的时间给出了具体建议。最后,以改进的技术方案为基础,针对某装置HAZOP分析过程为例,与改进前HAZOP分析过程进行了对比。     

Combining HAZOP with dynamic simulation—Applications for safety education

A quantitative variation of the hazard and operability analysis (HAZOP) procedure is demonstrated. The process is divided into sections and dynamic models of the separate sections are prepared. Those models are used in the framework of the HAZOP procedure to determine the magnitude of the deviations from normal operation conditions that may lead to serious accidents and to test design modification to improve the safety characteristic of the process. A process involving an exothermic reaction conducted in a semi-batch reactor is used to demonstrate the advantages of the proposed procedure and its application for safety education and operator training. The programs used for simulating the reactor are available at: ftp://ftp.bgu.ac.il/shacham/OctanoneProd/.

It is shown that the use of those programs can enhance considerably the safety education by providing tools for systematic screening of process deviation associated with possible hazardous events, determining the threshold values that may lead to such events and enabling the examination of a particular design for the adequate safe range of operation.     

A novel knowledge database construction method for operation guidance expert system based on HAZOP analysis and accident analysis

An expert system for operation guidance will contribute to identifying the operatoration problems and indicating the resolutions thereof, because the information stored in the expert system can be utilized to resolve the corresponding technical problems. However, there are several problems that should be solved in the practical application of the expert system, such as lack of corresponding knowledge or resolutions utilized to cope with the problems, inapplicable resolutions, too many resolutions for the operators to choose from to obtain the best one in the first time, etc. Obtaining and storing as much as information in the database of the expert system are important issues in the construction process of the expert system. The accident analysis results contain a limited number of accident cases and the HAZOP analysis only refers to a single deviation analysis. This paper has presented a novel knowledge database construction method for an operation guidance expert system based on the HAZOP analysis and the accident analysis, which can be used to resolve the above problems. The HAZOP analysis results are combined with the accident analysis results and the combination information can be stored in the database of the expert system, and can be employed to forecast accidents or identify accident causes. The structures of the operation guidance table and the accident investigation table have been illustrated. The residuum hydrotreating process expert system is taken as an example to illustrate the knowledge database construction method. With the aid of this expert system, the operators will well understand the operations and adopt the best resolutions to deal with the abnormal situations. Also the operators can identify potential risks existing in the plant which will result in accidents according to the accident analysis results associated with the HAZOP analysis results.     

HAZOP研究与故障树分析在合成氨装置危险辨识中的应用

合成氨装置的原料、产品危险性高,并且生产过程复杂,因此在运行过程中可能导致火灾、爆炸、中毒等事故,有些事故甚至给社会和环境造成严重破坏.对HAZOP研究与故障树分析进行组合,应用在合成氨装置的危险辨识中.通过HAZOP研究,合成氨主体装置共发现风险因素23项,其中合成氨装置的合成气压缩单元安全隐患较多,因此对其进行故障树分析,合成气压缩机单元火灾、爆炸故障树的最小割集为72个,最小径集为6个.从基本事件结构重要度结果来看,压缩机三级出口压力探测器( PIA3-2)故障,对压缩机发生火灾、爆炸的影响程度最大,应重点防范.     

HAZOP 分析在酸性水汽提装置上的应用与研究

危险与可操作性分析对于石化装置的工艺安全管理具有重要意义,介绍了HAZOP分析方法在工艺装置上的应用流程,并讨论了HAZOP分析与风险矩阵的结合运用。以克拉玛依石化公司的80吨/小时酸性水汽提装置为例,详细阐述了HAZOP分析的流程及其与半定量分析相结合的方法在实践中的应用,并针对危险源给出了风险削减措施。基于HAZOP分析在实践中的应用情况,总结了一些客观存在的问题,并提出了意见和建议。     

HAZOP分析中LOPA的应用研究

通过分析危险与可操作性研究(HAZOP)方法的不足和保护层分析(LOPA)方法的功能,提出将LOPA融入HAZOP分析中,能进一步提高HAZOP的事故预防能力和丰富HAZOP的分析结果。介绍LOPA基本方法,阐述LOPA融入HAZOP的机理、衔接关系及分析步骤,并通过一个化工工艺流程危险性分析实例说明LOPA的作用及如何将LOPA融入HAZOP分析中。结果表明:在HAZOP分析中融入LOPA方法,能实现对现有保护措施的可靠性进行量化评估,确定其消除或降低风险的能力,从而寻求是否需要附加减少风险的安全保护措施。     

A new approach of integrating industry prior knowledge for HAZOP interaction

Accidents often occur in the petrochemical industry, which have a negative impact on society and the environment. Learning Process Safety Knowledge (PSK) from accident cases is essential to prevent accidents and improve safety level. Hazard and Operability Analysis (HAZOP) is a popular hazard risk analysis method. Its report contains large-scale PSK, which can provide safety analysis and decision support for the industry. Subject to the characteristics of PSK, existing researches mine them in the form of sequence labeling. However, there are two intractable problems that cause the PSK mined by the model to be inaccurate. (1) PSK in HAZOP is domain specific, which is rare or even absent in general-domain texts. (2) The entity boundaries are ambiguous. Most domain-specific entities for HAZOP lack boundary characters. Inaccurate security knowledge is not acceptable from the perspective of process safety engineering. To solve the problems, we present a PSK mining architecture with External Lexicon Prior knowledge called EDPMA, EDPMA is prior knowledge-based multi-task HAZOP knowledge mining model. Specifically, EDPMA consists of prior knowledge constructor and sequence labeling model. The prior knowledge constructor expresses prior knowledge in the form of word embedding by three steps. For the sequence annotation model, we improve its embedding and decoding layers. The former incorporated the word vectors generated by the prior knowledge constructor, and the latter added the task of entity boundary prediction. We conduct multiple evaluation experiments on HAZOP datasets. The experimental results show that the accuracy, recall and F1-score of the EDPMA model are 92.92%, 91.85% and 92.38% respectively, which is better than the existing research. Our study represents a meaningful attempt to introduce prior knowledge in HAZOP knowledge mining and makes an important contribution to intelligence the field of process safety.     

Integration of process control protection layer into a simulation-based HAZOP tool

This paper discusses the framework methodology behind the proposed simulation-based HAZOP tool. Simulation-based approach is one of the many ways to support conventional HAZOP by its automation. Compared to knowledge-based and other approaches, a HAZOP software tool based on deviations simulation is able to examine the investigated process more into detail and so find root causes of hazardous consequences. Another advantage is the ability to identify also potential hazards which did not occur in the past and might be overlooked. The presented framework methodology uses a layer of protection analysis (LOPA) concept of independent protection layers (IPLs) testing. Control system integrated into the raw process design represents the first of various protection layers of the LOPA concept. As a case study, a CSTR chemical production with nonlinear behavior under Proportional-Integral-Derivative (PID) actions as the predominant type of classical feedback control strategy is used. The presented tool identifies hazardous regimes under conditions when control loop introduces hazardous consequences or even acts synergically with existing hazardous events. Risk derived from different consequences is ranked by the risk assessment matrix (RAM) as a part of the conventional quantitative HAZOP study.     

Using a system theory based method (STAMP) for hazard analysis in process industry

Different hazard analysis techniques are used in the chemical process industry. Most of these techniques were developed long time ago. There is an argument that significant changes have occurred in the process industry but these techniques have not been modified accordingly. Therefore, there may be limitations in identifying hazards related to the modern process industry in complex sociotechnical environment using these techniques. Recently new hazard analysis techniques based on systems theory have been introduced. STPA (System-Theoretic Process Analysis) is one of these systemic techniques. It has been used in some fields with promising results but with limited application in the process industry. This paper applies STPA to a process plant as an industrial case study. Recommendations generated by STPA are compared with the HAZOP study of the process plant which is a traditional technique. Conclusions are presented on the application of systemic techniques to the process industry as a complementary study to analyze the safety of the system as a whole and also to capture interactions between component of the system. Further studies are required to study STPA in more details and evaluate if it can be used as an alternative to HAZOP.     

化工生产事故预防信息系统研究

为指导操作人员正确地处理化工生产过程中的问题,防范人为误操作导致的事故发生,开发了以化工生产的危险与可操作性分析结果和典型事故原因分析结果为知识库的事故预防信息系统.系统实时在线监测化工生产过程中的关键变量,通过判定变量间的影响关系,实现对化工生产过程潜在危险的辨识、预警并给予实时操作指导,以确保生产安全,提高装置的生产效率.最后,以丙烯聚合工艺为例,在多功能过程试验控制平台上进行了验证,探讨了事故预防信息系统的应用方法.     

Integration of safety instrumented system with automated HAZOP analysis: An application for continuous biodiesel production

Integration of a human-machine interface (HMI) with hazard and operability (HAZOP) analysis is proposed in this work. This concept can potentially lead to the identification of some unexpected deviations, and radically decreases the time necessary for hazard identification. A continuous biodiesel production was simulated. This can be divided into two cases, covering both conventional and reactive distillation. Soybean oil (trioleic, trilinoleic and tripalmitic) at 1000 kg/h as raw material is converted to 99 wt% pure biodiesel. The HMI was designed to improve these processes by combining automatic HAZOP analysis. With this approach, users can receive sufficient information from the simulation to analyze the optimum operation and safety. Severity levels are also provided to classify the actions in the process. Severity levels 1 and 2 are concerned with operating conditions, which are 58-64 °C, and 50-150 kPa. If the analysis shows severity level 3, the safety instrumented system (SIS) will automatically manage the operation in order to reduce/restrain the amount of damage at this level. This proposed system could minimize the damage and also improve the overall quality of the process.     

基于SDG模型的HAZOP分析方法在钻井作业中的应用

HAZOP分析方法是目前危险性分析领域最盛行的分析方法之一,广泛地应用于石油化工行业。但是其分析过程仅依靠专家积累的知识与经验,不仅评价的内容不严格,而且分析的可信程度有限,对实际工作的指导意义不高,不能适应工业现场的要求。鉴于HAZOP分析方法中的不足,提出了基于SDG模型的HAZOP分析方法,并利用该方法对钻井作业过程进行了危险性分析。基于SDG模型的HAZOP分析方法从复杂系统的内部逻辑入手,进行深层次的推理,不仅提高了分析效率,而且分析所得结果的完备性较好。     

A new intelligent assistant system for HAZOP analysis of complex process plant

There are several problems that should be solved in the practical application of HAZOP analysis, such as the inheritance instrument of experience knowledge, the classification of accident reasons, the recurrence of analysis process and the verification of analysis results. This paper presents a new HAZOP assistant program named HELPHAZOP, which can be used to cope with these problems. With the aid of this program, a number of influence relationship models, which can be utilized to present the relationship structure of the whole system, can be established, and a variety of spread paths, which can be employed to describe the occurrence of the accidents, can be identified. These models and paths can help analyzers to understand the analysis process of different chemical processes and to verify the analysis results. Experience knowledge or information of process parameters stored in this program, including deviations, abnormal reasons, consequences and disaster-causing ways, can contribute to the analysis of some new plants. The program has been applied in the HAZOP analysis process of residuum hydrotreating process. The probability of the human errors which would be happened because of the misunderstanding or the deficiency of plant experience in the HAZOP analysis has been reduced and the accuracy, practicability and analysis efficiency of the accident forecast have been greatly improved.     

Safety study of an LNG regasification plant using an FMECA and HAZOP integrated methodology

A safety analysis was performed to determine possible accidental events in the storage system used in the liquefied natural gas regasification plant using the integrated application of failure modes, effects and criticality analysis (FMECA) and hazard and operability analysis (HAZOP) methodologies. The goal of the FMECA technique is the estimation of component failure modes and their major effects, whereas HAZOP is a structured and systematic technique that provides an identification of the hazards and the operability problems using logical sequences of cause-deviation-consequence of process parameters. The proposed FMECA and HAZOP integrated analysis (FHIA) has been designed as a tool for the development of specific criteria for reliability and risk data organisation and to gain more recommendations than those typically provided by the application of a single methodology. This approach has been applied to the risk analysis of the LNG storage systems under construction in Porto Empedocle, Italy. The results showed that FHIA is a useful technique to better and more consistently identify the potential sources of human errors, causal factors in faults, multiple or common cause failures and correlation of cause-consequence of hazards during the various steps of the process.