This paper addresses the issue of excitation inrush current during zero-crossing power regulation on the high-voltage side of an electric heating transformer. A simulation model is established using the MATLAB platform to systematically investigate the influence of key factors such as firing angle, core residual flux, load rate, and load characteristics on the inrush current under loaded conditions. Quantitative and qualitative analyses are performed on the variation characteristics of the primary-side current and core flux during zero-crossing power regulation. The results show that load characteristics significantly affect the inrush current: the inductive reactive component of the load exacerbates the inrush current, whereas the capacitive reactive component can mitigate it to some extent. Moreover, when the closing angle is 90°ahead, the inrush current can be completely eliminated. Regarding inrush current suppression methods, phase-selection control achieves excellent suppression but involves high complexity, while soft-start control is simple to operate but generates a large number of odd harmonics.

Leakage occurred at the bottom of a vacuum residue tank in Tank Farm No.17 of a large refining and chemical company in central China. To clarify the causes of corrosion perforation at the tank bottom and adopt effective protection measures to reduce the risk of corrosion-induced leakage, this paper takes the bottom corrosion of vacuum residue tanks as the research object and elaborates on the mechanism and various causes for pitting corrosion and perforation at the tank bottom. Then it puts forward targeted protective countermeasures so as to improve the safe operation of storage tanks.

To address issues such as insufficient quantitative risk assessment in leakage accidents of in-service crude oil storage tanks, this paper introduces a mathematical method combining the Poisson process with a continuous physical model. First, it is assumed that the number of leakage events follows a Poisson distribution. Taking the annual expected oil spill volume as the core risk indicator, the orifice outflow equation is employed to quantitatively model the leakage consequences under different leakage scenarios, and a sensitivity analysis of key parameters is conducted. The study shows that although small-hole leakages occur with higher frequency, their individual consequences are limited, and their risk contribution is mainly reflected as a long-term cumulative effect. In contrast, although rupture leakages have a lower probability of occurrence, the resulting oil spill volume per event is extremely large, making them the key factor dominating the overall risk level and uncertainty. The sensitivity analysis indicates that the annual occurrence rate of rupture leakages and the leakage duration have a significant amplifying effect on the risk level.

Due to the constraints of upstream station processes, the KL gas pipeline often carries some hydrocarbon liquids during operation. Combined with the significant undulating terrain along the route, liquid accumulation is prone to occur in low-lying sections of the pipeline. This seriously threatens the stable and safe operation of the pipeline and downstream stations. Therefore, this paper proposes a method for predicting and analyzing liquid accumulation in wet gas pipelines. Based on HYSYS modeling, the composition data of the outlet gas is formulated with reference to the measured hydrocarbon dew point and water dew point of the outlet natural gas; phase analysis confirms the possibility of natural gas liquid condensation along the entire pipeline, with condensate oil dominating and condensate water being minimal. Combined with the analysis of the critical inclination angle for liquid accumulation in the pipeline, it is found that the critical inclination angle has gradually increased recently. Within the segment from the starting point to the 2# valve chamber, sections where the actual inclination angle exceeds the critical inclination angle in upward slopes along the gas flow direction are prone to liquid accumulation; even when the flow rate is increased to the design capacity, liquid accumulation cannot be completely avoided. The findings of this study can provide important reference for the production operation and safety management of this pipeline.

In recent years, with the increasing loading and unloading frequency of reforming feedstock and naphtha at the terminal, leakage incidents of metal hoses have become more frequent and pitting corrosion is the predominant corrosion form. According to incomplete statistics, leakage of metal hoses at the terminal has exceeded 10 times in the past five years. This poses a significant safety hazard to production activities in riverside areas. Through on-site judgment and experimental data analysis, it is concluded that the accumulation of Cl- in the troughs of metal hoses leads to an increase in concentration, which is the main cause of corrosion. Through on-site analysis, electrochemical experiments and coupon tests, it is verified that the increase in Cl- concentration causes the corrosion failure of metal hoses and the corrosion mainly occurs in the troughs of metal hoses. Based on the experimental data analysis, anti-corrosion measures for metal hoses and methods to extend their service life are proposed.

This paper studies the long-term ammonium salt crystallization and corrosion problems in the overhead circulation system of the No.1 coking unit at Sino-Korea (Wuhan) Petrochemical Co., Ltd., and proposes installing a samarium-cobalt ammonium salt processor after the overhead circulation reflux pump to treat the overhead circulating oil. The results show that this technology can effectively transfer ammonium salts from overhead oil to sewage, prevent ammonium chloride crystallization and deposition in the overhead system, reduce fractionator top corrosion, and extend the unit's stable operation cycle.

At present, road transportation accidents of hazardous chemicals occur frequently in China. To reduce such accidents and enhance system safety, this paper focuses on accident prediction. In view of accident prediction, it adopts a BP neural network optimized by the improved particle swarm optimization (PSO) algorithm based on collected accident data to predict the severity of hazardous chemicals road transportation accidents in China and analyze the accident causes. The results indicate that severe accidents are more likely to occur during the early morning hours, under poor visibility or adverse weather conditions such as fog, and when transporting hazardous chemicals such as explosives and flammable liquids in road transportation. Case validation demonstrates that the PSO-BP neural network model achieves an average prediction accuracy of 84.9% and it can effectively correct errors of the single model. This study can provide more reliable data support for analyzing and assessing safety trends in road transportation of hazardous chemicals, and offer assistance in the formulation of accident prevention and control strategies as well as decision-making.

In the context of the “Dual Carbon” strategy, green and low-carbon transition constitutes the inevitable pathway for refining and chemical enterprises to overcome development bottlenecks and enhance their overall competitiveness. Drawing on field research and engineering practice and taking Enterprise E (a refining and chemical enterprise) as the research subject, this paper systematically reviews and elaborates the core practical pathways of its green transition, covering four key dimensions: production-side transformation, product-side upgrading, energy and resource synergy, and the construction of safeguard systems. The actual implementation of Enterprise E’s green transition engineering strategy has demonstrated significant reduction in the enterprise’s comprehensive energy consumption, total carbon emissions, and pollutant emission levels, achieving industry-leading standards. This study translates the green transformation imperatives of the refining and chemical industry into concrete and actionable practical solutions. It provides guidance and reference for the refinement and implementation of green transition engineering strategies in refining and chemical enterprises, and offers valuable insights for the transition of similar enterprises.

To promote the construction of the dual prevention system for work safety and further enhance the HSE management of chemical enterprise projects, this paper proposes the fuzzy structural entropy weight method. Taking the HSE management of a project in a chemical enterprise as an example, this paper establishes a dedicated HSE risk evaluation index system covering four dimensions: rules and regulations, HSE investment, hazard control and maintenance management, and proposes an HSE management risk evaluation method based on the structural entropy weight method. This method adopts the structural entropy weight method to quantify the uncertainty of indicator data and scientifically assign weights to each index. It avoids the bias of subjective weighting and the limitation of objective weighting that neglects the internal structural relationship among indicators. The results show that the HSE management risk score of this chemical enterprise project is 93, corresponding to a low safety risk level. The evaluation results are consistent with the actual site conditions and this provides technical support for on-site HSE management.

Against the backdrop of further advancement of the Belt and Road Initiative and the continuous deepening of international engineering cooperation, personnel stationed in overseas projects are confronted with cross-regional and multi-dimensional complex security risks, while cross-cultural cognitive disparities further pose greater challenges to management. This paper focuses on the safety and security needs of personnel in overseas projects. Drawing on case studies from multiple regional projects, it systematically constructs an implementation framework for cross-cultural safety training from the dimensions of system design, content development, format innovation, on-site execution and effectiveness evaluation. Through precise risk adaptation, tailored content development, diversified format innovation and collaborative execution mechanisms, the framework facilitates full-process coverage of safety training from theory to skills. It provides replicable technical pathways and practical paradigms for enhancing personnel safety awareness and emergency response capabilities, thereby reducing project safety risks.

Under the background of the steady advancement in oil and gas resource development and reserve growth and production increase in the East China Sea, the operation and maintenance business of the offshore platforms and onshore terminals have been growing continuously. The utilization of the company’s existing production site resources is nearly saturated, and the site expansion is constrained by multiple factors including cost, location and procurement procedures. This paper introduces the concept of lean management that centers on waste elimination and value creation to systematically upgrade facilities and optimize spatial layouts. By fully implementing visual management and 6S management, standardizing material control, and regulating employee behavior, a long-term mechanism featuring full participation and continuous improvement has been established. These measures have achieved the goal of efficient coordination of personnel, materials and the working environment. While significantly improving operational efficiency and economic benefits, they have comprehensively strengthened the company’s on-site safety control capabilities and helped the company to achieve leapfrog improvement in safety management.

The DuPont safety philosophy emphasizes prevention at the source, full participation, and continuous improvement, which is highly consistent with the high-risk characteristics of the refining and chemical industry.This paper takes the DuPont safety philosophy as the core and deeply explores its practical paths and optimization strategies in the safety management of refining and chemical enterprises. The paper systematically analyzes the main risks faced by refining and chemical enterprises including fire and explosion, equipment failure, environmental pollution, human error and special operations. Based on the ten core principles of the DuPont safety philosophy, a practical framework covering risk pre-control management, process risk control and post-incident control is proposed. The effectiveness of this framework is verified through case analysis. The research results indicate that the DuPont safety philosophy can significantly enhance the inherent safety of refining and chemical enterprises and provide a solid theoretical basis and practical reference for the safety management of the industry.

To address the safety challenges posed by the increasing scale and integration of petrochemical plants, this paper explores approaches to establishing a Process Safety Management (PSM) system and implementing digital and intelligent transformation solutions. Scientific decision-making must be grounded in the modelling uncertainties inherent in Quantitative Risk Assessment (QRA); meanwhile, human factors management based on behavioral science—such as ABC analysis and the Fogg model—is key to driving the management transformation from “post-incident accountability” to “systematic prevention and control”. Drawing on corporate practice, Analyses the innovative application of “digital and intelligent” technologies in proactive risk management. The future development of safety management lies in the deep integration of “systematization” and “intelligentization”. By establishing a modern PSM system and deeply integrating technologies such as big data and artificial intelligence, the inherent safety of enterprises can be continuously enhanced.

Nitrogen oxides (NOx) are major air pollutants that cause acid rain, photochemical smog and exacerbate the greenhouse effect, making their emission control a key focus in the environmental protection field. As China’s environmental standards become increasingly stringent and the petrochemical industry continues to develop, higher requirements have been placed on pollutant emissions from petrochemical enterprises, particularly ethylene plants. Currently, the industry widely adopts the combined technical approach of "Low-NOx burners + selective catalytic reduction (SCR) denitrification systems" to control NOx emissions in flue gas. To meet the stringent NOx emission standards and ensure efficient and stable operation of denitrification systems in ethylene plants utilizing "low-NOx burners + SCR" technology, this paper analyzes common operational anomalies such as excessive NOx emissions and ammonia slip, and proposes optimization measures, aiming to provide valuable insights for fault diagnosis and cost-effective operation of denitrification systems.

Large container calibration operations involve capacity measurement of various storage tanks. In petrochemical enterprises, metal storage tanks are widely used in large quantities with varying types and conditions, and most store hazardous chemicals, resulting in high safety risks that must be controlled. An integrated Bow-tie-JSA (Job Safety Analysis) model is established to provide a systematic, streamlined processes, and quantitative safety risk assessment mindset. This study integrates Bow-tie and JSA analytical approaches to analyze root causes of hazardous events from the perspective of energy or hazardous/toxic material release, and identify hazard factors triggering source release as well as potential hazardous incidents. Based on Bow-tie analysis, a risk control model is developed. JSA is conducted for the entire operation process, and referring to the Sinopec risk matrix, the risk value (RI) is quantified to ensure acceptable residual risks. A complete set of standardized operating procedures is thus established to reduce accident probability and ensure safe and efficient large container calibration operations.

This study systematically diagnoses and analyzes the causes of unstable nitrogen removal efficiency in the wastewater treatment system of a refinery during actual operation. The wastewater treatment system of this enterprise features a complex process flow, comprising multiple sets of treatment units for oily, saline and chemical wastewater. The research identifies the AO (anoxic-oxic) process as the weak link in the system’s nitrogen removal. This is attributed to inhibitory impacts on nitrifying bacteria and insufficient denitrification resulting from fluctuations in influent COD load, alkalinity deficiency and imbalance in dissolved oxygen distribution. From multiple dimensions including water quality characteristics, process parameters and microbial ecology, Analyzes the bottleneck of nitrogen removal. Furthermore, optimization strategies centered on enhancing biological nitrogen removal in the front-end process are proposed. These include optimizing operational parameters, precise dosing of carbon sources and alkalinity, aiming to improve the overall nitrogen removal efficiency and operational economic efficiency of the system.

To address the issue of low accuracy in existing environmental monitoring and early warning methods for oilfield bases, an online early warning method for abnormal data based on LS-SVM is proposed. The least squares support vector machine (LS-SVM) is adopted to construct a regression model following the principle of structural risk minimization. The complexity of the model is characterized by kernel function parameters. Predictions are then performed on environmental monitoring data, and the data are normalized to unify their scales. Empirical parameters are set to describe the prediction error. When the error satisfies the standard normal distribution condition, an anomaly is determined. The error sequence is then compared with a threshold, and an early warning is triggered once the error exceeds the threshold range. Experimental results show that the proposed method can effectively identify abnormal fluctuations in monitoring data with an early-warning accuracy of 100%. It can fully detect abnormal time series and markedly improve the timeliness and accuracy of environmental anomaly early warning for oilfield bases.

As an emerging approach for oily sludge treatment, ultrasonic technology demonstrates significant potential. Starting from the physicochemical properties of oily sludge, this paper analyzes the challenges posed by its stable emulsified structure and elaborates in depth the action mechanisms of ultrasonic cavitation and mechanical demulsification. It focuses on the synergistic application of ultrasonic technology combined with surfactants, extraction techniques and advanced oxidation processes to enhance oil-water-solid separation efficiency. Guided by the principles of “resource recovery, reduction and harmless treatment”, this study proposes optimization strategies to address the current bottlenecks of high energy consumption and scale-up, aiming to enhance crude oil recovery efficiency and facilitate efficient resource recycling and environmental remediation of oily sludge.

In the production process of shale oil refining in mining areas, a certain amount of oily sludge is produced each year, which requires regular collection, cleaning and storage. The treatment and disposal of hazardous waste is a key challenge that this project aims to overcome. The research, development, and engineering design of the process for extracting shale oil from oily sludge are carried out under normal temperature and pressure. While ensuring production safety, the process integrates the treatment and disposal of oily sludge into the production process, thereby separating shale oil from the sludge. This approach turns waste into valuable resources and increases economic benefits. It overcomes the challenges of complex procedures and high costs associated with hazardous waste treatment, representing a pioneering design in the oil shale industry. The equipment operates in a closed system, producing no toxic or hazardous gases, and complies with national environmental protection requirements. With no risk of secondary pollution, it delivers considerable environmental and social benefits.