Journal of Loss Prevention in The Process Industries最新文献

Domino incidents in process industries entail cascading failures, demanding thorough analysis to uncover root causes and enhance safety measures. Standard criteria are crucial for systematically evaluating incident investigation techniques, ensuring informed decision-making and consistency. Multi-Criteria Decision Making (MCDM) methods offer a structured approach to technique selection. This study addresses the need for systematic evaluation and prioritization of criteria influencing domino accident analysis technique selection. Through a comprehensive literature review, 16 main criteria and 42 sub-criteria were identified and weighted using the Logarithm Methodology of Additive Weights (LMAW) method, incorporating expert opinions. Results indicate the significance of criteria like applicability, accuracy, and comprehensiveness. Conversely, criteria such as relevance, cost-effectiveness, and emergency response team consideration had lower weights but remained significant. Findings regarding sub-criteria highlight the importance of consistent application of investigation methods and understanding sequential incident progression. This study advances domino accident investigation practices, promoting safety in process industries.

Industrial applications adopting toluene as a solvent have been largely extended in recent years, including solutions within the framework of the energy transition and energy storage technologies. The potential use of this flammable compound in a different set of operative conditions and compositions requires a comprehensive and complete knowledge of its fire behaviour and combustion kinetic. To this scope, an innovative experimental procedure applicable to liquid reactive systems was developed for this scope and implemented at different boundary conditions. More specifically, the specimen was exposed to air and heat fluxes between 7 and 50 kW/m², at a constant sample surface of 0.01 m², an initial sample thickness of 0.01 m, and a distance between the sample and the horizontally oriented conical-shaped heater of 0.025 m. Measurements were compared with data from the current literature, when available, demonstrating the robustness and validity of the adopted procedure. Although an increase in the external flux leads to growing mass burning rates (i.e., from 0.47 g/s to 0.85 g/s), negligible effects on the ignitability were observed. Conversely, a peak in the heat release rate at 35 kW/m² was measured. The observed reduction at higher external heat fluxes was attributed to less effective combustion, demonstrating that the maximum expected heat flux cannot be considered as an aprioristic worst-case scenario for the evaluation of pool fires. The collected data were, then, further utilized to obtain insights on the formation of the main products, including soot tendency. Based on the collected data a simplified kinetic model suitable for the computational fluid dynamics was proposed to reproduce the chemistry of the system.

A two-phase organic dust explosion is more complex than a single dust or gas explosion and poses a more significant threat to industrial safety production. To elucidate the explosion mechanism of two-phase organic dust, this study investigated the characteristics of flame propagation in PP/propylene hybrid explosions and revealed the flame propagation mechanism. The research findings indicate that adding propylene makes the flame brighter and more continuous, and velocity and temperature increase significantly. The introduction of propylene shifts the control of flame propagation from a process dominated by pyrolysis explosion kinetics to one governed by premixed gas explosion kinetics. Dimensionless characteristic numbers Bi and Da were introduced further to analyze the control mechanism of the dust explosion process. It was found that the explosion process was mainly diffusion flame combustion and premixed gas phase combustion.

Tank pool fire domino effects, represented by their capacities of accident consequence escalation and extensive damages, present substantial safety challenges within chemical storage systems. In this work, the inherent safety concept is introduced to proactively address these challenges while ensuring cost-effectiveness. Accordingly, a dedicated novel metric called Inherent Safety & Economic Risk Index (IS&ERI) is proposed to make safety and cost trade-offs for indicating the risk levels of various tank farm layout options. To develop the IS&ERI, the Dow's loss estimate procedure is adapted for representing the economic implications, and the Bayesian Networks are employed for indicating the failure probabilities of target units considering the synergistic effects of multiple pool fires. Two improved graph theory metrics are presented to determine the root nodes of the Bayesian Networks. For demonstrating the proposed IS&ERI, a case study is conducted and the results show that the IS&ERI of 4 tank farm layout options are 0.2991, 0.3120, 0.3525, and 0.2285, implying that Option 4 is the best layout with the lowest potential loss in case of the pool fire domino effects. As the key research contribution, the IS&ERI is presented and it can be used as a useful tool to compare and select the best tank farm layout option to eliminate or significantly reduce the knock-on effects of tank pool fires at their sources.

Liquified Natural Gas (LNG) is becoming an important energy source as clean energy. In cities with inland waterways, LNG tank containers transported by inland vessels will be the primary mode of transportation. However, the night sailing of LNG carriers is typically prohibited considering the safety of the vessels and surroundings. Inland LNG tank container carriers have to wait at specific anchorages during the prohibition period and complete the full voyage in segments. During the anchoring phase, the vessels pose significant risks with LNG leakage and dispersion as the primary ones. In this study, taking the anchoring LNG tank container carrier in the Yangtze River in China as a case study, a comparative simulation study is performed using the computational fluid dynamics model to investigate the influencing risk factors. The leakage and dispersion of LNG under extremely unfavorable conditions are also analyzed to calculate the safety area and provide the corresponding safety management suggestions. The comparative analysis results indicate that the leakage aperture is the primary influential factor, followed by wind speed and temperature. The simulations under extremely unfavorable conditions reveal a maximum dispersion range of 190 m and a safety zone radius of 310 m. These results provide important technical guidance and reference values for the case of leakage and dispersion on inland waterways.

To ensure the process safety of powder particles during pneumatic transport, a dust explosion experimental apparatus was designed to simulate the dust transport process. The system is supplied with a stable airflow by a high-pressure fan, capable of continuously transferring dust from the vessel to the pipeline at a controllable speed. Dust explosion experiments were meticulously executed by applying 1 kJ of ignition energy to the transported dust particles at airflow velocities of 5, 10, and 15 m/s. This study examines the effects of dust concentration, airflow velocity, and pipe diameter on explosion characteristics and delves into the mechanisms these effects through a detailed analysis of experimental results. The results demonstrate that the starch explosion flame progresses through four distinct stages within the vessel: flame development, flame stretching towards the pipe, intense combustion of starch particles, and complete combustion of the particles. As airflow velocity and pipe diameter increase, the stretching effect on the flame becomes more pronounced. At an airflow velocity of 15 m/s within a pipeline, a balance is struck between intensified particle combustion rates and unconstrained discharge, resulting in a maximum explosion pressure of 135.56 kPa for a 100 mm diameter pipe, with a maximum pressure rise rate of 7.27 MPa/s. Additionally, flame propagation velocity is higher at the pipe inlet. Different flame behaviors were observed inside the pipeline under varying airflow speeds. Compared to previous studies that utilized high-pressure gas to create dust clouds within vessels for explosion experiments, the results of this study underscore the crucial impact of airflow velocity on dust explosions. This research provides critical parameters for explosion prevention and presents a case study on the safety of dust handling processes.

In recent years, Chinese-produced bulk chemical products have consistently ranked among the world’s leading suppliers. The scale of individual petrochemical plants and chemical parks has grown significantly, resulting in increased complexity that can contribute to higher levels of uncertainty surrounding potential losses. MA (major accident) indicators can provide a comprehensive assessment of a plant’s safety performance. This study focuses on three primary objectives: Firstly, utilizing process safety management software powered by Industrial Internet technology, we develop MA indicators. Secondly, applying the Systems-Theoretic Accident Model and Processes (STAMP) theory, this work analyzes the logical relationship between MA indicators and accidents. STAMP provides a more comprehensive understanding of indicators involving multiple barriers. Lastly, drawing upon a large language model, this paper retrospectively analyzes 212 accident reports to verify the connection between the index and actual accidents. It is noteworthy that the MA indicators adhere to SMART criteria for effective measurement.