Hazards In Process Industries Research Articles

Explaining of the experts' points of view about the types and importance of man-made hazards in Iran’s process industries: A qualitative study

IntroductionProcess industries may have different hazards that can cause serious injury to humans, the environment, and the economy. Considering the importance of man-made risks in process industries, Experts' Points of View should be considered to apply risk reduction strategies Hence, the present study was performed to explain the views of experts regarding the types and importance of man-made hazards in process industries. Materials and methodsThis study was conducted using a qualitative method of directed content analysis with a deductive approach. The participants included 22 experts in the field of process industries. The selection of samples started purposeful and continued until data saturation. Data collection was done through semi-structured interviews. ResultsBased on experts' points of view, 5 man-made hazards in process industries were classified into 14 subcategories. The man category was divided into three subcategories: human error, technical knowledge error, and management error, the Material category was divided into 3 sub-categories of leakage and rupture, chemical properties, physical properties, Medium category was divided into two sub-categories of incorrect location selection and placement and harmful environmental factors, Machines category was divided into three sub-categories of failure in design, failure in Preventive Maintenance (PM), failure in Safety Instrumented System (SIS), and the Methods category was classified into three sub-categories: defects in inspection, defects in information, defects in executive instructions. ConclusionTechnical training to reduce personnel errors, conducting risk-based inspections to control leaks and possible ruptures, careful design and site selection in the initial phase of the project, is recommended. The use of engineering methods and artificial intelligence to obtain the risk number and control methods to reduce the harmful effects of risks can be helpful.

Investigations on vapor cloud explosion hazards and critical safe reserves of LPG tanks

To clarify vapor cloud explosion hazards in process industries and strengthen emergency treatment measures, a full-scale liquefied petroleum gas (LPG) tank model was established using computational fluid dynamics (CFD). Also, gas dispersion behavior and explosion hazards under different leakage characteristics were investigated and LPG safe reserves reasonably predicted. The results showed that heavy gas expansion near the ground mainly moved along gaps between structural congestions, while continuous large-scale congestion had significant enhancement effects on gas expansion and concentration accumulation. When an LPG cloud with nonuniform concentration ignited, the turbulent flame impacted the diluted explosive cloud at high speed, resulting in more serious consequences. When LPG leakage exceeded 300 s and the aperture greater than 10 mm, the hazard zone (Pc > 2 kPa) sharply increased and therefore considered to be the key factor in controlling explosion hazards. The LPG safe reserve varied little under low protection distance (Rp) and critical overpressure (Pc), but increased exponentially when Rp and Pc exceeded 200 m and 20 kPa, respectively. The present research conclusions provided a theoretical reference for emergency disposal, disaster assessment, and reserve safety design of LPG leakage and explosion accidents.

Prioritization of Human Factors Variables in the Management of Major Accident Hazards in Process Industries Using Fuzzy AHP Approach

Background: Human factors play an important role in process safety and can have dramatic effects on the safety performance of organizations. In addition, human factors are very important elements in safety management system and management of major accident hazards in process industries. Many variables of human factors may affect the safety in process industries, which need to be addressed in a more holistic approach. Objectives: This study was designed to determine the most important variables of human factors in the management of major accident hazards in process industries through the fuzzy analytic hierarchy process (fuzzy AHP) approach in 2017. Methods: After specifying human factors variables including the job, the individual (personal), and the organization factors and related sub-factors, fuzzy AHP approach was proposed to determine the weights and the degree of importance of factors and related sub-factors. Factors and related sub-factors were weighted using triangular fuzzy numbers in pairwise comparisons and fuzzy linguistic variables. Results: Organization factors got the highest relative weights (0.381) in comparison with other studied factors. Among organization sub-factors, safety culture had the highest importance (0.33). Among individual sub-factors, competence of personnel is recognized as the most important sub-factor (0.37). The highest relative weights for job sub-factors were obtained for ergonomic design and environmental factors (0.17). Conclusions: Determining and identifying the most important variables of human factors in process safety are very important for organizations. The present study demonstrates that organization factors are the most important variables in the management of major accident hazards in process industries with the application of fuzzy AHP. Safety culture, staff competence, ergonomic design, and environmental factors are the most important sub-factors.

Layers of protection analysis to achieve safety integrity level (SIL), Case study: Hydrogen unit of refinery

To identify and evaluate hazard in process industries as oil and gas, there are various methods in which hazard and operability study (HAZOP) and layers of protection analysis (LOPA) are the most common methods. The present study aims to analyze layers of protection to achieve safety integrity level in hydrogen unit of refinery. After performing library studies and data collection of events in refinery, hazards of hydrogen unit as operating nodes and deviations with causes and consequences are identified using HAZOP method. The next stage is presenting corrective solutions by LOPA method and target factor. Then, frequencies are determined for the initiating event by the experts. By completing the sheets of each event, independent layers of protection and integrity level are determined. The results of evaluation of identified risks showed that 11 cases had risk higher than 15 and it is not acceptable. The analysis of consequence of hazards showed that for 6 hazardous points, independent layers of protection can reduce risk as 100% to target factor (10-5) and safety integrity level is fulfilled. Regarding the eighths scenario “elimination of repulsive system of equipment and lines with the high temperature of very hot steam”, layers of protection cannot increase safety integrity level to more than 60% (10-3) and to provide safety to target factor, after eliminating the identified problems, other layers are positioned. In this study, to achieve safety integrity level in hydrogen unit of refiner. A three period plan (short-term, mid-term and long-term) is proposed.

Consequence modelling of dust explosion

Dust explosion is a serious hazard in process industries where combustible dust is handled. Dust explosion commonly occurs in a confined space such as a silo, a vessel or a warehouse. Based on industrial accidents involving dust explosion, it may cause fatality, injury and property damage. Therefore, a practical approach for integrated risk management of dust explosion hazards is required. This research focuses on the development of a spreadsheet tool for predicting the severity of dust explosion. The consequence modelling is required to enable the assessment of risk associated with dust explosion. Various published models were studied for initial work of consequence modelling. Parameters considered were the dust deflagration index (Kst), the maximum explosion pressure (Pmax), the maximum rate of pressure rise (dP/dt)max and the laminar burning velocity (Slbv). Reliable value for these dust explosion parameters has been tabulated based on closed vessel laboratory tests. A case study of dust explosion involving maize starch in closed vessel was used to test and validate the developed consequence modelling tool. The modelling result was discussed by comparing the predicted value against experimental value. The spreadsheet tool that was developed in this work can be used for the purpose of risk management of a facility associated with dust explosion hazards. It can be used to assist the application to combustion suppressant agent and design of explosion venting to prevent and mitigate the consequence of dust explosion. Keywords Consequence modelling, dust explosion, risk assessment Language: en