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This chapter delves into the dynamic interplay between economic drivers and environmental concerns within the context of methane, a potent greenhouse gas and a crucial component of modern energy systems. The chapter presents a comprehensive analysis of the economic underpinnings of methane as a global energy source, highlighting its pivotal role in meeting increasing energy demands and fueling economic development worldwide. It meticulously assesses the investments, innovations, and infrastructure shaping the methane storage and transportation industry and emphasizes the economic significance of methane in the face of ever-evolving production and consumption patterns. However, this economic advantage is accompanied by pressing environmental challenges. The chapter provides a detailed exploration of the environmental implications associated with methane emissions during extraction, storage, and distribution processes. It underscores the contribution of methane emissions to global warming, air quality deterioration, habitat disruption, and water resource implications, offering insights into their diverse sources encompassing natural and anthropogenic origins. In light of these intricate dynamics, the chapter advocates for a balanced approach. It underscores the urgency of mitigating methane emissions to combat climate change and protect the environment. The energy sector's substantial role in these emissions is acknowledged, along with opportunities for mitigation through technological advancements and strategic measures. Ultimately, this chapter seeks to strike an equilibrium between the undeniable economic significance of methane and the imperative to address the environmental challenges it poses. It offers a roadmap for navigating this complex relationship, ensuring that methane remains a vital component of the global energy landscape while safeguarding the health of our planet. © 2024 Elsevier Inc. All rights reserved.
Energy Conversion and Management (01968904)305
The research conducted a comprehensive techno-economic analysis and optimal design of a hybrid renewable energy system (HRES) integrated with grid connection, utilizing a case study focused on an oil refinery plant. The study explores the feasibility of incorporating solar, wind, and biomass energy sources alongside the existing Natural Gas Combined Cycle (NGCC) power plant and grid connection to meet the substantial energy demands of the refinery. By considering technical parameters and economic factors, including energy purchase prices, inflation rates, and environmental considerations, the research evaluates three distinct scenarios encompassing various combinations of the dedicated NGCC power plant, grid connection, and renewable energy sources, providing a holistic assessment of the energy supply strategies. The results reveal that the integration of renewable energy sources, especially in the context of reduced grid capacity, can lead to about a 44.6% reduction in carbon dioxide emissions and approximately a 32% reduction in net present cost compared to the base design without any renewable energy integration. This significantly enhances the economic viability and environmental sustainability of the oil refinery plant, contributing valuable insights into the optimal configuration of hybrid energy systems for large-scale industrial applications and addressing the challenges of energy security, cost-effectiveness, and environmental impact. © 2024 Elsevier Ltd
Barahoei, M.,
Kasiri r., R.,
Kooravand s., S.,
Feghhipour, S.E.,
Toghyani, M. 4pp. 411-432
Contemporary society faces a significant challenge of effectively utilizing clean energy for future needs, which is inextricably linked to the stability of the Earth, economic development, and human life quality. Fuels comprise approximately 70% of the overall energy demands of the world, particularly in the domains of transportation, industry, and residential heating. The environmental degradation engendered by the consumption of fossil fuels, coupled with the finite reserves of these fuels, has spurred greater attention to be directed towards biofuels. Biofuels are fuels derived from biomass sources, and algae, in particular, are one of the most vital and beneficial sources of biofuels. Algae harness the free energy source of sunlight and biologically capture carbon dioxide, thereby providing oxygen and valuable biomass. Liquid ethanol, methanol, biodiesel, as well as gaseous diesel fuels such as biohydrogen and biomethane, can be procured from algae. The present chapter pertains to investigating various types of gaseous biofuels derived from algae, while also examining the challenges of producing gaseous energy from algal sources on an industrial scale and exploring future perspectives. © 2024 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
Solar and wind-based hybrid technologies have emerged as promising alternatives to fossil fuels, offering enhanced reliability, efficiency, and sustainability in power generation. This chapter examines the current state of solar and wind-based hybrid technologies, focusing on their key components, operational characteristics, and integration challenges. Various hybrid system configurations, including grid-connected and standalone setups, are explored, analyzing their performance in terms of power generation, stability, and economic feasibility. Optimization techniques for system configuration and dispatch strategies are discussed, considering the complexities inherent in these hybrid systems. The chapter also addresses challenges related to variability and uncertainty, grid integration, cost-effectiveness, scalability, and environmental impact. By synthesizing existing literature, this chapter contributes to the understanding and development of sustainable energy solutions. It offers valuable insights for policymakers, researchers, and industry professionals involved in the integration and deployment of solar and wind-based hybrid technologies, facilitating the transition towards a cleaner and more sustainable energy future. © 2024 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
Chemical Engineering and Processing - Process Intensification (02552701)133pp. 303-311
An experimental investigation is performed for the desulfurization of model and real fuel oil samples through one-pot extraction combined with oxidation method with an acid catalyst under UV-irradiation. The kinetics of desulfurization process is obtained by fitting the data taken from a pilot-scale reactor. The effects of various operating parameters on the desulfurization efficiency and the optimal process condition were statistically analyzed using Taguchi experimental approach. The most important parameters affecting the desulfurization efficiency are temperature and the amount of acid catalyst. The obtained optimum conditions are applied to the three real fuel samples. The results of applying UV assisted and ultrasound assisted desulfurization are compared. Both methods have high desulfurization efficiencies about 90% for kerosene fuel. The desulfurization efficiency of about 75% for high sulfur diesel is obtained after a two-stage UV assisted desulfurization process. The results show that in the same conditions UV assisted process consumed ten times less energy than ultrasound assisted desulfurization. © 2018 Elsevier B.V.
Journal of Environmental Chemical Engineering (22133437)5(1)pp. 1244-1251
A mathematical model is introduced for the extractive separation of aromatic from aliphatic hydrocarbons in a counter current rotating disc contactor (RDC). The Mass conservation law is applied for toluene/n-heptane/solvent system to predict the concentration variation of toluene in continuous and dispersed phases along the column length. The obtained results are compared with the available experimental data of a pilot-scale contactor. This model is developed with two perspectives: with plug flow approach and with back mixing effects. The effect of parameters, like inlet solvent flow rate, rotor speed and extraction temperature on the contactor performance is studied. Disregarding back mixing effects for solvents with low viscosity leads to enormous errors in prediction of concentration profiles. An increase in the solvent flow rate and extraction temperature results in higher de-aromatization efficiency of extraction process while the rotor speed does not have noticeable consequence on the final performance of extraction column. © 2017 Elsevier Ltd. All rights reserved.
Energy (18736785)91pp. 1049-1056
An industrial process is synthesized and developed for decoking of de-hydrogenation catalyst, used in LAB (Linear Alkyl Benzene) production. A multi-tube fixed bed reactor, with short length tubes is designed for decoking of catalyst as the main equipment of the process. This study provides a microscopic exergy analysis for decoking reactor and a macroscopic exergy analysis for synthesized regeneration process. The dynamic mathematical modeling technique and the simulation of process by a commercial software are applied simultaneously. The used model was previously developed for performance analysis of decoking reactor. An appropriate exergy model is developed and adopted to estimate the enthalpy, exergetic efficiency and irreversibility. The model is validated with respect to some operating data measured in a commercial regeneration unit for variations in gas and particle characteristics along the reactor. In coke-combustion period, in spite of high reaction rate, the reactor has low exergetic efficiency due to entropy production during heat and mass transfer processes. The effects of inlet gas flow rate, temperature and oxygen concentration are investigated on the exergetic efficiency and irreversibilities. Macroscopic results indicate that the fan has the highest irreversibilities among the other equipment. Applying proper operating variables reduces the cycle irreversibilities at least by 20%. © 2015 Elsevier Ltd.
Bulletin Of Chemical Reaction Engineering And Catalysis (19782993)10(2)pp. 155-161
The Pt/γ-Al2O3 catalyst life time was limited by the formation of coke on the external and internal sur-faces of catalyst in dehydrogenation reactors. The kinetics of decoking of dehydrogenation catalyst was studied in a pilot scale fixed bed reactor experimentally. The effects of temperature, oxygen concentra-tion and other operating conditions on decoking process were investigated. A kinetic model was deve-loped to describe the decoking of mentioned catalyst. An objective function was defined as the sum of squares of the deviations among the calculated and plant data. Accordingly the appropriate values were found in order to minimize this function. It was concluded that there was a good agreement be-tween simulation results and experimental data. © 2015 BCREC UNDIP. All rights reserved.
Applied Catalysis A: General (0926860X)489pp. 226-234
The present study provides a dynamic mathematical model for a regeneration process of coked catalysts in a multi-tube fixed-bed reactor. Mass and energy conservation laws are applied to predict the temperature variation of gas and solid phases along the reactor length in two main stages: heating and coke burning. The kinetics of decoking is obtained by fitting the data taken from a pilot-scale reactor. The model results are compared with the experimental data taken from both a pilot-scale and a commercial-scale plant. The effect of operating parameters, including inlet gas flow rate, temperature, and composition on the reactor performance is studied. Controlling the O2 concentration is the best strategy to prevent the catalyst sintering. In order to reduce the regeneration process duration, two strategies are examined: constant and stepwise rising trend of inlet O2 concentration. Using the inlet O2molar-fraction of 5.5% reduces the regeneration duration by about 4 h. © 2014 Elsevier B.V. All rights reserved.
