STUDY OF THE PROCESS OF OXIDATIVE DESULFURIZATION OF DIESEL FUEL IN THE PRESENCE OF CO-CATALYSTS

Continuous growth in consumption of oil in the world, as well as ever-increasing quality requirements stimulate the search for new scientific and technological solutions to directionally affect the characteristics of petroleum products, including their chemical composition. The advantages of oxidative desulfurization before hydrotreating are the absence of the need to use hydrogen, as well as small capital and energy costs, since the method does not require high temperatures and pressures. The purpose of this work was to study the oxidation process of diesel fuel and to search for the optimal mode of oxidative desulfurization of diesel fuel in the presence of transition metals salts with the addition of mineral acids. The object of the study is a straight-run diesel fraction of the Pavlodar Petrochemical Plant with boiling temperatures of 180-350°C. The oxidation process was carried out with hydrogen peroxide in the presence of salts of the transition metals molybdenum, vanadium and tungsten. The article defined the basic physico-chemical characteristics of straight-run and desulfurized diesel fractions. The optimal catalyst (Na2MoO4) was selected at a molar ratio of metal to sulfur of 1:100 for the oxidation process of straight-run diesel fractions. As a result of oxidative desulfurization of diesel fuel in the presence of sodium molybdenum perox complexes, the total sulfur content decreased by 42.9%, and with the addition of sulfuric acid by 56.5%. An increase in the cetane index from 56.3 to 58.6 was revealed in the presence of sodium molybdate with the addition of sulfuric acid.

Development of Advanced Advisory System for Anomalies (AAA) to Predict and Detect the Abnormal Operation in Fired Heaters for Real Time Process Safety and Optimization

As the technology is emerging, the process industries are actively migrating to Industry 4.0 to optimize energy, production, profit, and the quality of products. It should be noted that real-time process monitoring is the area where most of the energies are being placed for the sake of optimization and safety. Big data and knowledge-based platforms are receiving much attention to provide a comprehensive decision support system. In this study, the Advanced Advisory system for Anomalies (AAA) is developed to predict and detect the abnormal operation in fired heaters for real-time process safety and optimization in a petrochemical plant. This system predicts and raises an alarm for future problems and detects and diagnoses abnormal conditions using root cause analysis (RCA), using the combination of FMEA (failure mode and effects analysis) and FTA (fault tree analysis) techniques. The developed AAA system has been integrated with databases in a petrochemical plant, and the results have been validated well by testing the application over an extensive period. This AAA online system provides a flexible architecture, and it can also be integrated into other systems or databases available at different levels in a plant. This automated AAA platform continuously monitors the operation, checks the dynamic conditions configured in it, and raises an alarm if the statistics exceed their control thresholds. Moreover, the effect of heaters’ abnormal conditions on efficiency and other KPIs (key performance indicators) is studied to explore the scope of improvement in heaters’ operation.

Salix purpurea and Eleocharis obtusa Rhizospheres Harbor a Diverse Rhizospheric Bacterial Community Characterized by Hydrocarbons Degradation Potentials and Plant Growth-Promoting Properties

Phytoremediation, a method of phytomanagement using the plant holobiont to clean up polluted soils, is particularly effective for degrading organic pollutants. However, the respective contributions of host plants and their associated microbiota within the holobiont to the efficiency of phytoremediation is poorly understood. The identification of plant-associated bacteria capable of efficiently utilizing these compounds as a carbon source while stimulating plant-growth is a keystone for phytomanagement engineering. In this study, we sampled the rhizosphere and the surrounding bulk soil of Salixpurpurea and Eleocharis obusta from the site of a former petrochemical plant in Varennes, QC, Canada. Our objectives were to: (i) isolate and identify indigenous bacteria inhabiting these biotopes; (ii) assess the ability of isolated bacteria to utilize alkanes and polycyclic aromatic hydrocarbons (PAHS) as the sole carbon source, and (iii) determine the plant growth-promoting (PGP) potential of the isolates using five key traits. A total of 438 morphologically different bacterial isolates were obtained, purified, preserved and identified through PCR and 16S rRNA gene sequencing. Identified isolates represent 62 genera. Approximately, 32% of bacterial isolates were able to utilize all five different hydrocarbons compounds. Additionally, 5% of tested isolates belonging to genera Pseudomonas, Acinetobacter, Serratia, Klebsiella, Microbacterium, Bacillus and Stenotrophomonas possessed all five of the tested PGP functional traits. This culture collection of diverse, petroleum-hydrocarbon degrading bacteria, with multiple PGP traits, represents a valuable resource for future use in environmental bio- and phyto-technology applications.

Effect of Imidazole as Corrosion Inhibitor on Carbon Steel Weldment in District Heating Water

Many research studies have been conducted on the corrosion inhibition performance of imidazole in acidic environments such as in the piping of a petrochemical plant. However, there has been no study on the effect of imidazole in alkaline conditions such as a local district water heating environment. Therefore, in this study, the effect of imidazole as a corrosion inhibitor on carbon steel weldment was investigated in alkaline district heating water. Inhibition efficiency and electrochemical properties were investigated by potentiodynamic polarization test and electrochemical impedance spectroscopy. As the concentration of imidazole increased up to 500 ppm, inhibition efficiency increased up to 91.7%. At 1000 ppm, inhibition efficiency decreased. Atomic force microscopy showed that surface coverage of imidazole at 1000 ppm is lower than that of imidazole at 500 ppm. X-ray photoelectron spectroscopy showed that with 500 ppm of imidazole, the amount of pyrrole type interaction is 4.8 times larger than pyridine type interaction. At 1000 ppm of imidazole, the amount of pyridine type interaction is 3.49 times larger than pyrrole type interaction. Depending on the concentration of imidazole, the ratio of interaction between carbon steel and imidazole affected inhibition efficiency.

Research on Action Layers and Application and Database Design of Safety Barrier in Petrochemical Plant

In recent years, petrochemical industry accidents occur frequently. The reason was that the existing safety measures were not comprehensive enough to protect all layers of production. It is an urgent problem for enterprises to improve the existing safety measures and form a system to cover all stages of production. Safety barrier can protect and control every layer of production, so as to protect the production process comprehensively, avoid, prevent and control accidents. Four action layers of safety barrier in petrochemical production were established, and the specific implementation method of safety barrier was proposed. This method was applied with taking atmospheric and vacuum distillation unit as an example. The results show that the atmospheric and vacuum distillation unit can be fully protected by the safety barrier through physical or non-physical means, and its safety has been significantly improved. Finally, the safety barrier database of petrochemical plant was designed and developed in order to manage the safety barrier information and make it convenient for personnel to use. The database functions include storing, querying, adding, modifying and deleting the names, categories, functions and specific description of the safety barrier.

Assessment of Occupational Exposure to BTEX in a Petrochemical Plant via Urinary Biomarkers

This work presents the results of the first Serbian monitoring campaign performed to assess the occupational exposure of petrochemical industry workers to benzene (B), toluene (T), ethylbenzene (E), and xylene (X), known collectively as BTEX. The following urinary biomarkers were investigated: phenol, hippuric acid, o-Cresol, p-Cresol, and creatinine. BTEX compounds were collected in 2014 using Casella passive samplers. Multivariate statistical analysis was performed to put in evidence the correlation between the BTEX measured in air and the concentration of urinary biomarkers. While the results indicate an elevated presence of benzene in the air in the working environment studied that surpasses the national and European Occupational Exposure Limits (OEL), the levels of the remaining (TEX) parameters measured were below the OEL. The high relative standard deviations (RSD) for the concentrations of each BTEX compound (68–161 mg m−3) point toward an intensive occupational exposure to BTEX. This was confirmed by relevant urine biomarkers, particularly by the mean values of phenol, which were ten and fourteen times higher than the ones found in the control group (14–12 mg g−1 of creatinine). On average, workers are at a higher risk of developing cancer (6.1 × 10−3), with risk levels exceeding the US EPA limits. Benzene levels should therefore be maintained under tight controls and monitored via proper urinary biomarkers.