Journal of Chemical Engineering and Energy Materials

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 The idea of using steam to produce mechanical work probably raised for the first time in relation to pumping water from coalmines. The first successful work in this case was a "Pump engine" made by Thomas Savory (1650-1715) in England. In the riding engine, steam directly applied with a pressure between 4.5 and 8 bar on the surface of the water located in a chamber and it raised in a pipe. In this engine, a one-way valve prevented the reverse flow of water. After the water emptied from the chamber, the flow of steam manually cut off and cold water entered the chamber so that more water would enter it by condensing the steam inside and creating a vacuum in the chamber. In this engine, because of direct contact between water and steam, the loss of steam due to condensation was high, and the lack of safety valves caused many explosions. Almost at the same time as Savory, Denis Papin (1647-1712), who was also the inventor of the safety valve, proposed the idea of separating steam and water by means of a piston, and Thomas Newcomen (1663-1729) designed and then built such a piston engine. In this engine, steam enters the vertical cylinder with low pressure and causes a piston to move upwards. Then, the steam that remains in the cylinder turned into a liquid from the outside by the direction of cold water, and thus a vacuum created in the cylinder.

Abstract Supercritical units usually work at a pressure of 24 MPa and above, which is higher than the critical water pressure of 22.09 MPa. A subcritical cylindrical steam generator usually works at about 13 MPa or 18 MPa. Many of the steam generators purchased in the 1970s and 1980s are cylindrical water tube types that operate at 18 MPa, produce superheated steam at 540°C, and have one or two stages of steam reheating. These generators have the ability to burn pulverized coal and petroleum fuels, although petroleum fuels gradually abandoned due to the increase in price and problems related to their supply. Although natural gas still used in power plants in some parts of the world, due to its high cost, it now mostly used for domestic purposes in the United States of America. Anyway, natural gas is a clean burning fuel and relatively pollution free. The steaming capacity of modern power plant steam generators is high and its value can vary from 125 to 1250 . Power plants are between 125 and 1300 megawatts. On the other hand, industrial steam generators are those that used in industrial companies and other institutions and include different types. These generators can be pulverized coal-fired water tube type steam generators, although they are powered by lump coal, oil or natural gas, and often a combination of them, as well as municipal waste, process waste energy, or other by-products also be used. In some of them even electric heating is used. Some of them are of the heat recovery type, in which the waste heat of industrial processes is used. These generators can also be of the fire tube type. Industrial steam generators usually do not produce superheated steam, but produce saturated steam or even only hot water.

Abstract Corrosion remains one of the most pervasive and economically burdensome challenges confronting modern industry, inflicting annual global costs estimated at approximately US$2.5 trillion, equivalent to 3.4% of the world's Gross Domestic Product . This comprehensive review synthesizes current knowledge on corrosion mechanisms, mitigation strategies, and industrial applications across critical sectors including oil and gas, marine infrastructure, wastewater treatment, and civil engineering. The analysis systematically examines electrochemical principles governing corrosion thermodynamics and kinetics, establishing that while thermodynamics predicts corrosion spontaneity through Gibbs free energy calculations, kinetics determines the actual degradation rate . Key corrosion morphologies—uniform, pitting, crevice, galvanic, intergranular, stress corrosion cracking, and microbiologically influenced corrosion—are characterized with emphasis on their distinct initiation mechanisms and propagation dynamics. Advanced mitigation approaches are critically evaluated, including protective coatings achieving >90% corrosion reduction, inhibitor systems demonstrating >95% efficiency in controlled environments, cathodic protection methodologies, and emerging self-healing technologies based on layered double hydroxide nanocarriers that exhibit 95–99.9% inhibition efficiency . Particular attention is devoted to green corrosion inhibitors derived from renewable sources and hybrid systems combining organic and inorganic functionalities for enhanced synergistic protection. The review further examines monitoring technologies, from non-destructive testing to AI-driven predictive models achieving reliability metrics exceeding 0.85 R². It concludes that effective corrosion management necessitates integrated, multi-layered approaches bridging laboratory mechanistic understanding with field-applicable, economically viable, and environmentally sustainable solutions.

Abstract Corrosion, the electrochemical degradation of metals, remains a critical global challenge with annual economic losses estimated at 3.4-5% of GDP in industrialized nations . This comprehensive review synthesizes recent advances in corrosion science, spanning fundamental electrochemical mechanisms to innovative protective technologies. The electrochemical framework—governing corrosion thermodynamics and kinetics—is examined through the lens of recent discoveries, including the role of passive film breakdown in localized attack and the emergence of microbiologically influenced corrosion as a pervasive threat across industries . Advanced characterization techniques, including electrochemical impedance spectroscopy and atomic force microscopy, have provided unprecedented insights into nanoscale corrosion initiation and propagation . The review systematically evaluates three transformative protection paradigms: smart self-healing coatings achieving market projections of USD 10.4 billion by 2028 through autonomous damage repair ; MOF-oligomer nanocomposites that synergistically integrate pH-triggered inhibitor release with redox-mediated passivation, demonstrating inhibition efficiencies of 75.62% and self-healing improvement of 229.67% ; and AI-driven monitoring frameworks achieving R² > 0.99 prediction accuracy for dynamic corrosion rate forecasting . Particular attention is devoted to sustainable solutions, including green inhibitors derived from renewable sources, nanotechnology-based multifunctional coatings, and integrated digital twin systems that bridge physics-based simulation with real-time IoT sensing . The review concludes that next-generation corrosion management requires convergent approaches combining mechanistic understanding, advanced materials, data-driven analytics, and environmental sustainability.

Abstract Corrosion represents one of the most pervasive and economically burdensome challenges confronting modern industry, with global annual costs estimated at approximately $2.5 trillion, equivalent to 3-4% of GDP in industrialized nations . Traditional corrosion inhibitors, including chromates, phosphates, and nitrites, have demonstrated high efficacy but pose significant environmental and health concerns due to their inherent toxicity, persistence, and bioaccumulative potential . This comprehensive review systematically examines the emerging paradigm of green corrosion inhibitors derived from renewable, biodegradable sources as sustainable alternatives for metal protection in aggressive environments. Plant extracts, agricultural wastes, biopolymers, amino acids, and naturally occurring organic compounds rich in heteroatoms (N, O, S, P) and conjugated π-systems have demonstrated inhibition efficiencies exceeding 90% through adsorption-driven protective film formation . The review elucidates fundamental adsorption mechanisms—physisorption, chemisorption, and mixed-mode adsorption—governed by molecular structure, surface chemistry, and environmental parameters. Recent innovations in hybrid inhibitor systems, combining green organics with inorganic nanoparticles or metal ions, have achieved synergistic efficiencies of 92-98% through enhanced adsorption strength, barrier integrity, and multifunctionality . Advanced characterization techniques including electrochemical impedance spectroscopy, potentiodynamic polarization, and surface analysis methods are critically evaluated. Computational approaches including density functional theory and molecular dynamics simulations provide mechanistic insights into inhibitor-metal interactions at the molecular level. Key challenges including performance variability, temperature sensitivity, scalability, and standardization are addressed. The review concludes that green corrosion inhibitors represent a viable, sustainable pathway for corrosion management across oil and gas, marine, and infrastructure sectors, with future progress dependent on integrated approaches combining mechanistic understanding, data-driven discovery, and field-relevant validation.