Journal of Chemical Engineering and Energy Materials

Abstract The production of polymers, particularly PVC and its related copolymers, requires stringent control of operating conditions to minimize occupational exposure to VCM. In industrial practice, VCM synthesis is typically conducted in fully closed systems, which effectively reduce atmospheric emissions and worker exposure. Nevertheless, due to its high flammability, VCM vapor poses a significant fire and explosion hazard. Accidental releases under pressure can also result in frostbite because of rapid depressurization. Furthermore, the potential for long–range vapor dispersion necessitates rigorous control of potential ignition sources and strict adherence to process safety protocols.
In this study, a comprehensive and rigorously validated process model for VCM production was developed using Aspen Plus. The balanced process, which integrates both direct chlorination and oxychlorination routes, was simulated to determine an optimized, energy–efficient, and industrially feasible configuration. Detailed molecular kinetic models were incorporated for all major reactor units, accounting for both primary and secondary reaction pathways. The thermodynamic framework was based on the modified SRK equation of state, ensuring accurate vapor–liquid equilibrium representation for multi-component systems. Model validation against published plant-scale data showed excellent agreement in conversion, selectivity, and yield predictions. The developed simulation framework provides a robust foundation for future work on process optimization, heat integration, and safety analysis in large-scale VCM production plants.

Abstract The relationship between industrialization and rural development in the texts of developing countries has different views, so that Rajesh Chandar has emphasized the role of industrialization in the development process by expressing these views and believes that the following views have made the role of industry in development more sensitive. Industrialization in developing countries is known as a historical necessity. In this regard, due to the lack of another provable model for development, historically this claim that development requires industrialization has been accepted. Due to the minimization of the competitiveness of the agricultural sector compared to the industrial sector and the significant reduction in the price of agricultural products compared to industrial products, the trade conditions in the agricultural sector are significantly limited and the tendency towards industrialization as it is an economic fact. Even if the manufacturing and production of goods in the process of industrialization is not considered as a desirable option for the development of the agricultural sector, the trend towards industrial activities can be a source of encouragement for the economic development process as a complement to the agricultural sector.

Abstract Corrosion in refinery units, particularly in Naphtha Hydrotreating (NHT) and Continuous Catalytic Reforming (CCR) units, represents a significant threat to operational reliability, safety, and economic efficiency. This study presents a comprehensive data-driven analysis of corrosion behavior in NHT and CCR units based on real-time plant data, historical maintenance logs, and process parameters. Using statistical and machine learning methods, we identify key operational factors contributing to corrosion rates, including temperature, pressure, hydrogen partial pressure, and contaminants such as chlorides and sulfur compounds. Furthermore, the study evaluates the effectiveness of different mitigation strategies such as corrosion inhibitors, metallurgy upgrades, process optimization, and vapor phase conditioning in various sections of the units, including reactors, heat exchangers, furnaces, and piping systems. It investigates how operating envelopes and process excursions influence the onset and progression of localized corrosion phenomena such as pitting, erosion-corrosion, and stress corrosion cracking. The findings aim to provide actionable insights for refining operators, integrity managers, and process engineers involved in asset management and corrosion control. The study further evaluates the effectiveness of various corrosion mitigation strategies including material upgrades, corrosion inhibitors, process control optimization, and predictive maintenance protocols. The findings aim to support refinery operators in making informed decisions to extend equipment life, reduce downtime, and enhance safety in high-temperature, hydrogen-rich environments.

Abstract Corrosion in Naphtha Hydro treating (NHT) units poses a significant challenge to the long-term reliability and economic performance of petroleum refineries. These units operate under severe conditions—high temperatures, elevated hydrogen pressures, and the presence of corrosive species such as hydrogen sulfide (H₂S), organic acids, and chlorides—which create an aggressive environment for materials of construction. This study investigates the key operational factors that influence corrosion rates in an NHT unit using a six-month dataset from a hypothetical refinery scenario. Data collected includes reactor temperature and pressure, feed sulfur content, amine inhibitor dosage, and field-measured corrosion rates from corrosion coupons installed in critical locations. Statistical analysis revealed strong positive correlations between corrosion rate and both feed sulfur content (r = 0.81) and reactor temperature (r = 0.74), while amine inhibitor dosage showed a moderate inverse relationship (r = -0.66). A multiple linear regression model was developed to predict corrosion rate as a function of these parameters, with an R² value of 0.83, indicating high predictive accuracy. Corrosion hotspots were identified at the reactor inlet and in the cold zones of heat exchangers, suggesting the need for targeted monitoring and material upgrades in those areas. The study concludes that optimizing feed quality, maintaining appropriate inhibitor dosing, and deploying real-time corrosion monitoring can significantly mitigate corrosion risk. The findings provide a quantitative foundation for corrosion risk assessment in NHT units and offer actionable insights for improving operational safety and asset longevity in hydro processing environments.

Abstract In the present study, while identifying potential risks and classifying them according to the Risk Breakdown Structure (RBS), we determine the criteria for identifying and assessing risks qualitatively, and then by converting qualitative criteria into quantitative ones and using the FMEA technique and calculating the Risk Priority Number (RPN) and responding to high-priority risks, we control the obstacles to achieving the project goals. By carrying out this process in the oil processing unit construction project, which was carried out using the EPC method, important and risky risks were identified and controlled based on the project phases, and precise control was exercised to prevent imposing additional and possible costs on the project and creating defects in its other objectives, so that important and influential risks on key project activities were organized in the form of a risk management plan, and their future and possible consequences, which could be one of the most important factors in the failure to comply with the project implementation plan, were minimized. The results of the present study showed that approximately 43% of the losses were due to mechanical integrity failure, and this percentage was higher for losses caused by oil refinery. Of these mechanical failures, 70% were identified as a result of corrosion of process pipes, mainly due to internal corrosion. In cases where external corrosion was the cause, the cause was insulation corrosion.

Abstract During six decades of development planning at the level of developing countries, which has been done with different forms and patterns. Development planning has not had a proper place and rural development is mainly based on tourism perspectives or physical functions and has never led to introspection and self-criticism, so that in our country in the last few decades by providing amenities and services to the villages, the process of migration has not decreased, and the provision of facilities without planning for employment and income has increased the expenses of the residents of the rural areas of the country, while the income has remained constant. In this way, rural areas have always played a role related to urban areas as a margin and far from the comprehensive thinking of development. Creating industries is one of the strategies that help the development of villages, the industrialization of rural areas as an accelerator for creating sustainable employment and the most effective solution to solve the problem of rural unemployment. The theory of industrialization and the optimal planning of industries in rural areas are considered as a catalyst for creating sustainable employment and as a last resort to solve the problem of poverty in the potential areas of the same region to solve the problem of unemployment and a soothing factor for disadvantaged rural areas. Come the consequences of the appropriate establishment of rural industries in temperate and humid rural areas, where the amount of agricultural land is decreasing every day, is considered a suitable solution.

Abstract Corrosion is a critical concern in refinery operations, particularly within the Crude Vacuum Unit (CVU), where high temperatures, acidic compounds, and variable feedstock compositions create a highly aggressive environment. This study investigates the extent and nature of corrosion affecting major components of the CVU, including furnace tubes, transfer lines, flash zones, and overhead condensers. Using ultrasonic thickness gauging (UTG), process stream analysis, and historical inspection data, corrosion rates were calculated and correlated with metallurgical characteristics and process conditions. The findings reveal that the highest corrosion rates occurred in the transfer lines due to naphthenic acid corrosion (NAC), especially under conditions with Total Acid Number (TAN) exceeding 1.0 mg KOH/g and operating temperatures above 230°C. Sulfidation in furnace tubes and erosion-corrosion in overhead systems were also prominent. Material selection played a significant role in corrosion resistance, with carbon steel components showing higher degradation compared to low-alloy and stainless steel counterparts. The study emphasizes the importance of feed monitoring, material upgrading, and optimized wash water injection to mitigate damage. Recommendations include the use of corrosion-resistant alloys, installation of online monitoring systems, and improved process control strategies. This research provides valuable insights for maintenance planning and risk reduction in vacuum distillation operations, contributing to improved asset integrity and operational efficiency in refineries.