Hazard And Operability Research Articles

Latest Technology to Manage the Complete Process Safety Lifecycle

Latest developments in software technology allow for the management of the complete Process Safety Lifecycle as defined in standard IEC-61511 for the Process Industry. Most companies in the Process Industry have accepted the necessity of conducting Process Hazard Evaluations e.g. HAZard and OPerability (HAZOP) studies and Layer Of Protection Analysis (LOPA), however it has been more challenging to follow-up on the recommendations and demonstrate that the Safety Instrumented Functions have been built and tested in accordance with the design specifications. Validating the assumptions of the Safety Study and a comparison with actual Process Safety performance in the Plant has proven to be cumbersome and was almost impossible in the past. Furthermore, there was little insight in the financial impact of Process Safety risks. Modern Technology facilitates the validation, hence allowing for the management of the entire Process Safety Lifecycle. Real measured Lead Process Safety KPI's can be produced, controlled and managed.

The Role of Façade Materials in Blast-Resistant Buildings: An Evaluation Based on Fuzzy Delphi and Fuzzy EDAS

Blast-resistant buildings are mainly used to protect main instruments, controllers, expensive equipment, and people from explosion waves. Oil and gas industry projects almost always include blast-resistant buildings. For instance, based on a hazard identification (HAZID) and hazard and operability (HAZOP) analysis of a plant, control rooms and substations are sometimes designed to withstand an external free air explosion that generates blast over pressure. In this regard, a building façade is considered to be the first barrier of resistance against explosion waves, and therefore a building façade has an important role in reducing a building’s vulnerability and human casualties. In case of a lack of enough resistance, explosion waves enter a building and bring about irreparable damage to the building. Consequently, it seems important to study and evaluate various materials used in a façade against the consequences of an explosion. This study tried to make a comparison between different types of building facades against explosion waves. The materials used in a building play a key role in the vulnerability of a building. In this research, a literature review and the fuzzy Delphi method were applied to find the most critical criteria, and then a fuzzy evaluation based on the distance from the average solution (EDAS) was applied in order to assess various materials used in building facades from the perspective of resiliency. A questionnaire was presented to measure effective indices in order to receive experts’ ideas. Finally, by implementing this methodology in a case study, it was concluded that a stone façade performs much better against explosions.

Application of hazard and operability analysis for safeguardability of a pyroprocessing facility

Pyroprocessing treats nuclear fuel using electrochemical techniques for a variety of applications, whether to process used uranium oxide fuel for back-end management, or to reprocess used metallic fuel for an advanced fuel concept. Since there are proliferation risks associated with special nuclear material (SNM) processed in a pyroprocessing facility, the high reliability safeguards (HRS) methodology has been developed to implement safeguards, safety, and physical security (3S) together with operations from a design-driven perspective. This paper suggests the design strategies by integrating a hazard and operability (HAZOP) analysis. It is a process hazard analysis, essential for identifying hazards, operability issues, severe accident scenarios, and for mitigating consequences with the corresponding protection methods. It is a preliminary step for an eventual quantitative, probabilistic risk analysis, which may be needed for obtaining an operating license for a commercial pyroprocessing facility. The focus of this HAZOP analysis was on major pyroprocessing subsystems; voloxidation, electroreduction, electrorefining, electrowinning, and the argon atmosphere control system. Deviations were analyzed from normal operating conditions, and methods were thoroughly prepared to prohibit or mitigate off-normal situations. Importantly, pressure buildup or high temperature in the systems can increase the risk of initiating fire/explosion, which may eventually release radiation to the outside. Safety relief valve installations, valve actuation and heater automatic shutdown systems, etc., would be helpful to alleviate operational problems. This enhanced HAZOP also suggests a strong safeguards design for the facility by proposing nuclear material accounting (NMA) locations for the purpose of reducing potential proliferation risks.

Evaluating human error data for hazards in air-traffic control and deriving a quantitative safety index

We developed an analysis method of hazards related to air-traffic control (ATC). We used mixing approach procedures such as required navigation performance, authorisation required (RNP AR) and instrument landing system (ILS), as the test case. We carried out the hazard and operability (HAZOP) study and ATC real-time simulation experiments in the situation of the mixed operation for finding the hazards because we were not able to find them as the result of literature examination. We collected the data required for this analysis in the simulation experiment and selected HAZOP as the key assessment methodology. The hazard analysis method developed enables to perform a quantitative HAZOP analysis. We quantified the likelihood of accidents and the ratios between the hazard severities at the development stage. Furthermore, we discussed a safety index based on the statistics of recent catastrophic air accidents around the world. A safety index matrix showed the regions of acceptable levels with mitigation by a quantitative index value.

Application of Industrial Risk Management Practices to Control Natural Hazards, Facilitating Risk Communication

Establishing a comprehensive management framework to manage the risk from natural hazards is challenging because of the extensive affected areas, uncertainty in predictions of natural disasters, and the involvement of various stakeholders. Applying risk management practices proven in the industrial sector can assist systematic hazard identification and quantitative risk assessment for natural hazards, thereby promoting interactive risk communication to the public. The objective of this study is to introduce methods of studying risk commonly used in the process industry, and to suggest how such methods can be applied to manage natural disasters. In particular, the application of Hazard and Operability (HAZOP), Safety Integrated Level (SIL), and Quantitative Risk Analysis (QRA) was investigated, as these methods are used to conduct key studies in industry. We present case studies of the application of HAZOP to identify climate-related natural hazards, and of SIL and QRA studies that were performed to provide quantitative risk indices for landslide risk management. The analyses presented in this study can provide a useful framework for improving the risk management of natural hazards through establishing a more systematic context and facilitating risk communication.

Computer Aided HAZOP Study Implementation Bottlenecks in Chemical Industry

Implementation of computer aided approach into hazard and operability (HAZOP) study is one of the most researched topics in the field of hazard identification improvement. However, acceptance of an automated HAZOP tool in the industrial practice is limited. This contribution provides retrospective analysis of application issues connected with the use of process simulations in computer aided HAZOP studies. As case studies, mathematical models utilising different sets of unit operations, e.g. plug flow reactor, continuous stirred-tank reactor, phase separator, heat exchanger etc. were analysed. Two different simulation platforms, commercial process simulator Aspen HYSYS and our own mathematical models in MATLAB, were employed. Relevant concerns regarding the use of process simulations in the HAZOP study such as model reliability and its parameter uncertainties effect on the HAZOP study output and interpretation variability of quantitative HAZOP deviations for process simulations are discussed. It is demonstrated that the application of process simulation is a feasible way to perform precise safety analyses of processes widely used in chemical industry. However, proper attention has to be paid to the construction and use of mathematical models in order to develop a suitable software solution.

ANALYSIS OF OPERATIONAL RISKS IN THE STORAGE OF LIQUID AMMONIUM NITRATE IN A PETROCHEMICAL PLANT, THROUGH THE HAZOP METHODOLOGY

The storage of liquid ammonium nitrate in a petrochemical plant, located at the Caribbean region of Colombia, is analyzed to identify and mitigate the risks present in it. Hazard and Operability (HAZOP) methodology was followed to assess the risks and hazards associated to this process. Initially, the ammonium nitrate storage tank was defined as the node to be studied, together with the instrumentation required for this operation. The diagrams of the node and technical specifications of the equipment and instruments were reviewed. This information, together with the operative, technical and conceptual knowledge of the staff at the plant, allowed to assess the deviations for operational variables such as temperature, pressure and level, among others, in order to identify the hazards and risk scenarios that can take place during the storage of ammonium nitrate. Based on the HAZOP analysis, recommendations were made to mitigate or avoid incidents that have an impact on people, environment or the company. This case study highlights the qualitative deviations and variables that require a constant monitoring and control for a safe storage of ammonium nitrate.

Software approach to simulation-based hazard identification of complex industrial processes

Process safety is of major importance in chemical industry. Numerous activities have targeted the modification of conventional risk assessment strategies by computer aided approach. In this paper, a software tool for Hazard and Operability (HAZOP) study based on process simulation is presented. Individual components of the proposed software tool are described and the principal methodology of their function is explained. As the simulation engine, commercial process simulator Aspen HYSYS was employed. Proposed tool was applied to a case study of an ammonia synthesis plant based on an existing plant. Hazardous events and operability problems in the syngas purification unit and ammonia synthesis loop have been detected and reported. The steady state multiplicity phenomenon in the ammonia synthesis loop has also been successfully identified. Based on simulation data evaluation performed in the semi-automatic manner by the proposed tool, a HAZOP-like report containing HAZOP deviations and their causes and consequences was generated.

Risk analysis of high level radioactive waste storage tank based on HAZOP

High-level radioactive liquid waste tanks have the possibility of releasing radioactivity, and thus it is of great importance to identify hazards in such storage tanks and take measures to improve their safety. In this paper, a hazard and operability (HAZOP) methodology is used to identify the hazards in a double-shell stainless-steel tank for high-level radioactive liquid waste storage for which a risk matrix was implemented to assess the risks posed by the hazard. First, during the HAZOP process, appropriate process parameters and guidewords were selected to describe the deviation of the storage tank, and the causes and possible consequences of deviations as well as existing protection measures were analyzed. The risk matrix then was used to evaluate the risk level of the deviation identified, combined with the consequences of the deviation as well as the associated likelihood of its occurrence. Results showed that primary tank leaks and hydrogen combustion or explosion in tanks are undesirable risks, and thus corresponding countermeasures were put forward. The analysis results could be used to provide guidance for safe operation of, and rectification of hidden dangers in, high-level radioactive liquid waste storage tanks.

Hazard Identification and Risk Assessment in Two Gas Refinery Units

Background: The analysis of causes and consequences of past accidents in gas refinery plants has indicated that the consequences of accidents in these plants may be catastrophic and irreversible, influencing human health, environment, and the economy. This study aimed at assessing risks using layer of protection analysis (LOPA) in gas sweetening units of 2 different gas refinery plants and determining the probability of initiating events with application of protection layers, using the event tree analysis (ETA) method. Methods: Hazard and operability (HAZOP) analysis was used in hazard identification. Data obtained from HAZOP analysis was applied to assess risks using the LOPA technique. The most likely scenarios were selected and the probability and consequences of initial events were determined using the ETA method. Results: Results of the HAZOP method led to identification of 52 risks and their levels in processes of both gas sweetening units, considering the control equipment. The results of LOPA showed that the levels of risk with different scenarios of both gas sweetening towers were similar. The probability of the total near misses in plant 1 and 2 were 0.00214753 and 0.00214149, respectively. The probabilities of incidents according to the top events in refinery 1 and 2 were 0.0000011 and 0.000005, respectively. Conclusions: The LOPA is a useful tool for the assessment of effectiveness of independent protection layers in reducing risk in both studied refinery plants. The results indicated that event tree analysis is an effective tool for quantitative analysis of consequences and probabilities of accidents in the studied gas refinery units.

Hazard and Operability (HAZOP) Study for Analyzing Disaster Risk Reduction in Hazardous Chemical Industrial Unit

Hazard and Operability (HAZOP) Study for Analyzing Disaster Risk Reduction in Hazardous Chemical Industrial Unit

A HAZOP gap query approach for hazard assessment in multiproduct facilities

Batch, multiproduct chemical processing facilities present special challenges for conducting thorough hazard assessments. New or improved methods are needed to perform quality hazard analyses while reducing time and resource demands on facility personnel. A technique has been developed to expand traditional hazard and operability (HAZOP) methodology to include additional parameters for process operational intent, chemicals, and affected upstream/downstream equipment. Integrated Layer of Protection Analysis (LOPA) is applied to assess existing or proposed Independent Protection Layers, and compare resulting mitigated risk to risk criteria limits. The HAZOP for each unit then becomes a baseline hazard assessment, to which subsequent processes can be compared, without having to repeat the full HAZOP for each new process. For new products, a process intent template is completed by selecting the chemicals and equipment to be used, as well as the unit operations and conditions for each step in a semibatch process. The unit HAZOP file is queried using programmed search logic to identify matching process intent/equipment/chemicals parameters that were considered during the base HAZOP. A condensed Process Hazard Review is conducted to review the results, ensure identified items are applicable to the proposed new process, and evaluate new items that were not previously covered under the base HAZOP. © 2017 American Institute of Chemical Engineers Process Saf Prog 37: 161–168, 2018

An open‐source biomass pyrolysis reactor

AbstractDespite its long history of technological development, much charcoal production still relies on polluting and inefficient technologies utilizing traditional kiln designs. In addition to the need for improved charcoal production systems, the growing interest globally in pyrolysis of biomass to generate biochar as a soil fertility improver and for climate change mitigation may drive an increasing demand for such technologies. Accordingly, there is a clear need in developing countries for access to safe, affordable, and efficient open‐source designs and technology that can be fabricated locally. The design described here includes computational fluid dynamics modeling which demonstrated that the design exhibits a stable flow and combustion pattern. A hazard and operability (HAZOP) study, mass and energy modeling, and costing of all components and fabrication were also conducted for a prototype kiln that will accept up to 250 kg biomass h‐1. Fabrication and installation costs were estimated using actual commercial quotations based on detailed engineering drawings and design, and were found to be $580 000 for a 250 kg h‐1 unit. We therefore find that this pyrolysis system promises to be economical on a small scale. It can utilize waste lignocellulosic materials for feedstock, thus alleviating demand pressure on woodlands to provide feedstocks. It was, therefore, concluded that the pyrolysis unit described here promises to provide an affordable and efficient open‐source design that can be fabricated locally in developing countries without licensing restrictions or royalties. © 2017 The Authors Biofuels, Bioproducts and Biorefining published by Society of Industrial Chemistry and John Wiley & Sons Ltd

Application of analytical hierarchy process (AHP) in prioritizing HAZOP analysis for pilot plant

<p>Injuries, accidents or even fatalities while working in pilot plant are reported worldwide. The implementation of process hazards analysis (PHA) in pilot plant is expected to further reduce the risks of accidents. Hazard and operability (HAZOP) analysis is one of the most widely used methods for PHA. Generally, the outcome of HAZOP analysis could results in identifying large number of hazards thus poses a challenge for assessors to take actions in dealing with all the hazards. The common practice in prioritizing the critical hazards is based on assessors’ experience through deductive judgment using rating scale, taking into consideration safety and the associated costs. However the novel operations and process used, unproven or changing technology, and lack of safety information due to developmental stages have led to poor hazards prioritization and difficulty in selecting actions. This paper presents an application of analytical hierarchy process (AHP) in prioritizing HAZOP analysis for pilot plant. Through this approach, the significant hazards identified using HAZOP will be quantitatively weighted and ranked based on their priority along with the appropriate counter measures to be taken. Application of this approach at the high pressure CO2-hydrocarbon absorption system pilot plants as case study showed that the proposed methodology is capable of identifying and ranking the significant hazards in the process following HAZOP analysis. This is particularly useful as a leading indicator to process designers/engineers/researcher in prioritizing their efforts and resources on more significant hazards, hence prevent accidents of the pilot plant.</p><p>Chemical Engineering Research Bulletin 19(2017) 87-95</p>

Hazop Study and Fault Tree Analysis for Calculation Safety Integrity Level on Reactor-C.5-01, Oil Refinery Unit at Balikpapan-Indonesia

plat former reactors are reactors that are in the plat forming unit is designed for developing your specific hydrocarbon molecules that are used in catalytic engine fuel in boiling point range naphtha and fuel mixture to produce components with a higher octane value. Plat former reactor system failure may disrupt operations in the oil processing refinery unit. These circumstances will cause the supply plaformat as products of the plat forming unit valued high octane which is the main raw material of gasoline blending system is reduced. Resulting in decreased production consequency large losses. The failure of the reactor system can also be harmful to the operator, the environment and there is a possibility of reactor unit may explode. To avoid these risks we conducted studies identify hazards that occur in the process rector Hazard and operability (HAZOP) analysis and calculate the value of safety integrity level (SIL). In this study reviewed three nodes Overview consisting of node stage 1, stage 2 and stage 3. Based on the results of identification are thirteen instruments on the third node, which includes equipment; PC-193, FI-005, PC-194 and FI-010. Standards-based Service Oriented systems have Unacceptable risk criteria and the criteria of likelihood 4 Consequences worth three. As for the evaluation of SIL is known that C-5-01 reactor system has two safety Integrity Function (SIS) located in the path of fuel gas and pilot gas lines of the reactor heater. Both SIS has a vote = 1oo3 architecture with similar characteristics, and a review of the SIS has a security level SIL = 2 with a value of PFD = 0.00103.

Safety and Environment aspects of Tokamak- type Fusion Power Reactor- An Overview

Naturally occurring thermonuclear fusion reaction (of light atoms to form a heavier nucleus) in the sun and every star in the universe, releases incredible amounts of energy. Demonstrating the controlled and sustained reaction of deuterium-tritium plasma should enable the development of fusion as an energy source here on Earth. The promising fusion power reactors could be operated on the deuterium-tritium fuel cycle with fuel self-sufficiency. The potential impact of fusion power on the environment and the possible risks associated with operating large-scale fusion power plants is being studied by different countries. The results show that fusion can be a very safe and sustainable energy source. A fusion power plant possesses not only intrinsic advantages with respect to safety compared to other sources of energy, but also a negligible long term impact on the environment provided certain precautions are taken in its design. One of the important considerations is in the selection of low activation structural materials for reactor vessel. Selection of the materials for first wall and breeding blanket components is also important from safety issues. It is possible to fully benefit from the advantages of fusion energy if safety and environmental concerns are taken into account when considering the conceptual studies of a reactor design. The significant safety hazards are due to the tritium inventory and energetic neutron fluence induced activity in the reactor vessel, first wall components, blanket system etc. The potential of release of radioactivity under operational and accident conditions needs attention while designing the fusion reactor. Appropriate safety analysis for the quantification of the risk shall be done following different methods such as FFMEA (Functional Failure Modes and Effects Analysis) and HAZOP (Hazards and operability). Level of safety and safety classification such as nuclear safety and non-nuclear safety is very important for the FPR (Fusion Power Reactor). This paper describes an overview of safety and environmental merits of fusion power reactor, issues and design considerations and need for R&D on safety and environmental aspects of Tokamak type fusion reactor.

The role of a commercial process simulator in computer aided HAZOP approach

Abstract Process safety is one of the key pillars of sustainable industrial development. In combination with the increasing use of computer aided process engineering, the demand for an appropriate model-based safety analysis tool capable to identify all hazardous situations leading to a major accident has increased. Commercial process simulators are equipped with extensive property databases and they employ high accuracy mathematical models providing the capability to simulate real behavior of a process operated within the area of the mathematical model validity. The main focus of this work is to improve standard hazard identification methods by the combination of hazard and operability (HAZOP) study and process simulation in commercial process simulator Aspen HYSYS. Software tool consisting of modules for computer simulation and complex analysis of simulation data will be proposed. The developed tool was applied to modern chemical productions exhibiting strong nonlinear behavior, where proper prediction of consequences can be very difficult. In the first case study, hazard identification in continuous glycerol nitration employing user-dependent analysis is presented. Mathematical methods of simulation data analysis independent of the user is demonstrated in the second case study of ammonia synthesis. Possibilities and limitations of the proposed tool are revealed and discussed in this work.

Risk assessment of a compound feed process based on HAZOP analysis and linguistic terms

The size and complexity of industrial plants, along with the characteristics of the products used, require a study, analysis and control of the existing risks in every industrial process.In this paper, a methodology for risk assessment in industrial plants, based on the combination of risks identification through the Hazard and Operability (HAZOP) analysis and the risks evaluation through linguistic variables and fuzzy numbers is applied to a case study consisting on a compound feed plant located in the town of Silla (Valencia, Spain).The results from this study show that the main risk in the compound feed production process is the formation of explosive atmospheres (ATEX). Therefore, the corrective measures will focus on reducing the concentration of dust in the atmosphere and eliminating the possible sources of ignition, such as electrostatic discharges or sparks during the different phases of the process (the grinding, the transport of the raw materials, etc.)

A new tool for risk analysis and assessment in petrochemical plants

The aim of our work was the implementation of a new automated tool dedicated to risk analysis and assessment in petrochemical plants, based on a combination of two analysis methods: HAZOP (HAZard and OPerability) and FMEA (Failure Mode and Effect Analysis). Assessment of accident scenarios is also considered. The principal advantage of the two analysis methods is to speed-up hazard identification and risk assessment and forecast the nature and impact of such accidents. Plant parameters are analyzed under a graphical interface to facilitate the exploitation of our developed approach. This automated analysis brings out the different deviations of the operating parameters of any system in the plant. Possible causes of these deviations, their consequences and preventive actions are identified. The result is risk minimization and dependability enhancement of the considered system.

An integrated hazard identification method based on the hierarchical Colored Petri Net

The traditional hazard analysis approaches applied to the socio-technical system cannot cover the complex organization structures, the interactions between systems and human behaviors, the interrelated factors among sub-systems and the safety culture of specific societies. This paper presents an integrated hazard identification approach named System-Theoretic Process Analysis Based on Formalization Model (BFM-STPA), which can solve the above issues. Firstly, the hierarchical control structure models of the socio-technical system are established through Colored Petri Nets (CPN) due to its strong description ability and executable ability, which may also be regarded as the graphical system specification. Secondly, the hazards can be identified according to the CPN models following a series of guide conditions. Thirdly, the comprehensive contributing factors to the hazards will be found out by tracing the former states within the reachability graph generated from CPN model. Finally, an integrated hazard log can be derived for further hazard analysis and safety-guided design. In this paper, the above method was applied in the Chinese Train Control System level 3 (CTCS-3). And the process of hazard identification for the scenario of Temporary Speed Restriction issued was elaborated in detail. Compared with the hazard log generated by Hazard and Operability (HAZOP), the hazard log generated by BFM-STPA covered not only the subsystem failures, but also the deviation of interactions among subsystems from design intent, human errors and socio-technical drawbacks related to the TSR Issued scenario of CTCS-3.