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    Optimal Model of Energy and Exergy of Iran’s Economic Activities and their Impact on the Environment

    , M.Sc. Thesis Sharif University of Technology Karimi, Mohammad Sadegh (Author) ; Saboohi, Yadollah (Supervisor)
    Abstract
    The economic activities in a country involved with depletion of natural resources and emission of pollutants and gases to the environment. Depletion of exhaustible resources and environmental pollutions are two determinants of sustainability of development. The present research work is aimed at studying the sustainability of Iranian economy in 2009. The analysis of sustainable development of economy is based the concept of exergy, exergy efficiency and ecological exergy efficiency. Exergy efficiency is the ratio of the exergy of a product in economic activity to the exergy of input streams to that section of economy. Ecological exergy efficiency is defined as the ratio of exergy of product... 

    Exergy analysis of a flat plate solar collector in combination with heat pipe

    , Article International Journal of Environmental Research ; Vol. 8, Issue. 1 , 2014 , Pages 39-48 ; ISSN: 17356865 Kargarsharifabad, H ; Shafii, M. B ; Rahni, M. T ; Abbaspour, M ; Sharif University of Technology
    Abstract
    The use of solar collectors in combination with heat pipes is rapidly growing in recent years. Heat pipes, as heat transfer components, have undeniable advantages in comparison with other alternatives. The most important advantage is their high rate of heat transfer at minor temperature differences. Although there have been numerous studies on the heat analysis or first thermodynamic analysis of flat plate solar collectors in combination with heat pipes, the exergy analysis of these collectors is needed to be investigated. In this work, energy and exergy analysis of a flat plate solar collector with a heat pipe is conducted theoretically. Next, the exergy efficiency of pulsating heat pipe... 

    Exergy analysis of an integrated gas turbine thermoacoustic engine

    , Article ASME 2010 4th International Conference on Energy Sustainability, ES 2010, 17 May 2010 through 22 May 2010, Phoenix, AZ ; Volume 1 , 2010 , Pages 945-951 ; 9780791843949 (ISBN) Ghorbanian, K ; Karimi, M ; Sharif University of Technology
    2010
    Abstract
    An attempt is made to utilize exhaust gases of a small gas turbine in augmenting power output through the employment of a thermoacoustic system. It is assumed that the thermoacoustic system is powered only by the waste heat of the gas turbine. A comprehensive cycle analysis of the integrated gas turbine thermoacoustic engine "IGTTE" is carried out from energy and exergy point of view. Results indicate the thermodynamic advantages of the IGTTE  

    Exergy-based responsibility allocation of climate change

    , Article University Initiatives in Climate Change Mitigation and Adaptation ; 2018 , Pages 291-315 ; 9783319895901 (Online ISBN); 9783319895895 (Print ISBN) Khajehpour, H ; Saboohi, Y ; Tsatsaronis, G ; Sharif University of Technology
    Springer International Publishing  2018
    Abstract
    Climate change as a serious environmental issue has been subjected to many management studies. Yet the issue of allocating global responsibilities to emission reduction in a reasonable way is an unconcluded challenge. Two main groups of responsibility allocation systems are production-based responsibilities (PBR) and consumption-based responsibilities (CBR). PBR takes territorial emissions within borders into account that is applied to global policy makings by the Intergovernmental Panel on Climate Change (IPCC). In contrast, CBR considers the emission transfers through international trade and allocates the responsibilities based on the goods and services being consumed by each country. Both... 

    Exergy and economic analysis of solar chimney in iran climate: tehran, semnan, and bandar abbas

    , Article Mathematical Modelling of Engineering Problems ; Volume 7, Issue 1 , 2020 , Pages 55-67 Ahmadi, M. H ; Mohammadi, O ; Sadeghzadeh, M ; Pourfayaz, F ; Kumar, R ; Lorenzini, G ; Sharif University of Technology
    International Information and Engineering Technology Association  2020
    Abstract
    Solar chimney is one of the attractive approaches to produce power from a clean source of renewable energy. In this investigation, a potentiometric study is carried out to find out a best location for construction of a solar chimney in different climates of Iran, in the Middle East. With this objective, three locations with different weather climates were chosen, i.e. Tehran, Semnan, and Bandar Abbas. These locations were chosen due to their different climatic conditions and solar irradiation. The used weather conditions are extracted for the middle day of summer, 6th August. The output power of the solar chimney plant was assessed as a function of various thermo-physical properties such as... 

    Thermoeconomic analysis and multi-objective optimization of a LiBr-water absorption refrigeration system

    , Article International Journal of Environmental Research ; Volume 9, Issue 1 , 2015 , Pages 61-68 ; 17356865 (ISSN) Abbaspour, M ; Saraei, A. R ; Sharif University of Technology
    University of Tehran  2015
    Abstract
    Performance optimization of a single-effect lithium bromide water absorption refrigeration system is the subject of this paper. First, the thermodynamic model of the system wasderived based on the first and second law analysis of an absorption refrigeration cycle with LiBr-water as the working fluid pair. Then, the effects of different design parameters such as the generator inlet hot water temperature, evaporator inlet chilling water temperature and absorber and condenser inlet cooling water temperatures on the performance of the systemwere investigated. In order that, by defining the coefficient of performance (COP), exergy efficiency (Second-law efficiency) and total cost function of the... 

    Energy and exergy analyses of a spark-ignition engine

    , Article International Journal of Exergy ; Volume 7, Issue 5 , 2010 , Pages 547-563 ; 17428297 (ISSN) Ameri, M ; Kiaahmadi, F ; Khanaki, M ; Nazoktabar, M ; Sharif University of Technology
    2010
    Abstract
    In this paper, the performance of an internal combustion engine is evaluated at the steady-state condition by application of energy and exergy analysis using the experimental test results. The energy and exergy balances are calculated at different engine speeds. The results show that the heat rejection of energy and exergy flow increases with increasing engine speed. The exergy efficiencies are slightly higher than the corresponding energy efficiencies. The results of this study have revealed that the most important source of the system inefficiency is the destruction of exergy by irreversible processes, mostly by the combustion. One can conclude that the use of a combined energy and exergy... 

    Exergy Analysis on Design of SMR Preheating Exchangers

    , M.Sc. Thesis Sharif University of Technology Shariati, Mohammad Hassan (Author) ; Farhadi, Fathollah (Supervisor)
    Abstract
    With the global oil price increase in recent years and fossil fuel resource scarcity, analyzing of fossil fuel consumer industries and optimization of their fuel consumption is an important rule. Exergy analysis is an efficient tool for this purpose in the chemical and petrochemical processes in recent years more than ever. Therefore, in this work, an exergy analysis is performed for heat recovery section of Steam-Methane Reforming (SMR) process as a major consumer of natural gas.
    This work contains five general section. At the first section, exergy and energy concepts, reforming processes and other related basic concepts are described. The second section is about the recent research and... 

    Energy and exergy assessments of modified Organic Rankine Cycles (ORCs)

    , Article Energy Reports ; Volume 1 , November , 2015 , Pages 1-7 ; 23524847 (ISSN) Safarian, S ; Aramoun, F ; Sharif University of Technology
    Elsevier Ltd  2015
    Abstract
    This paper presents a theoretical framework for the energy and exergy evaluation of a basic as well as three modified Organic Rankine Cycles (ORCs). The modified ORCs considered incorporating turbine bleeding, regeneration and both of them. The results demonstrate that evaporator has major contribution in the exergy destruction which is improved by increase in its pressure. The results confirm that the integrated ORC with turbine bleeding and regeneration has the highest thermal and exergy efficiencies (22.8% and 35.5%) and the lowest exergy loss (42.2 kW) due to decrease in cold utility demand and high power generation  

    A survey on exergy, energy and environmental analysis of sulfur recovery unit in case of five intensified configurations

    , Article Chemical Papers ; Volume 73, Issue 6 , 2019 , Pages 1529-1539 ; 03666352 (ISSN) Rostami, A ; Tavan, Y ; Sharif University of Technology
    Springer International Publishing  2019
    Abstract
    In this study, a combination of energy and exergy analysis is applied for the industrial sulfur recovery unit (SRU) in commercial simulation software. The data of energy and exergy are obtained from the simulator and Excel (for physical and chemical exergy), respectively. In doing so, five intensified SRU configurations namely: (1) hot gas bypass (2) acid gas bypass (3) inlet stream preheating (4) acid gas enrichment and (5) oxygen (air) enrichment are compared in terms of energy production, reaction furnace temperature, sulfur recovery and pollutant emission into environment. Then, irreversibility in these five arrangements is compared and all the proposed methods show higher useful exergy... 

    An exergetic model for the ambient air temperature impacts on the combined power plants and its management using the genetic algorithm

    , Article International Journal of Air-Conditioning and Refrigeration ; Volume 29, Issue 1 , 2021 ; 20101325 (ISSN) Khajehpour, H ; Norouzi, N ; Fani, M ; Sharif University of Technology
    World Scientific  2021
    Abstract
    4E analysis is used on a Brayton-Rankine combined cycle power plant (CCPP) with a dual pressure heat recovery steam generation (HRSG) system. A multi-objective genetic-based evolutionary optimization has been used to estimate the most optimal exergy efficiency status, exergy cost reduction, carbon emission reduction, and NOx emission reduction. For the validation of the data, the simulation results are compared with the plant's data. This study investigates the effect of every decisive parameter on the objective performance parameters of the CCPP. The primary estimated results are the emission rates, efficiencies, and the exergoeconomic cost of the system. At the optimum operational state,... 

    Exergoenvironmental and exergoeconomic modelling and assessment in the complex energy systems

    , Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 41, Issue 3 , 2022 , Pages 989-1002 ; 10219986 (ISSN) Norouzi, N ; Choubanpisheh, S ; Talebi, S ; Khajehpour, H ; Sharif University of Technology
    Iranian Institute of Research and Development in Chemical Industries  2022
    Abstract
    Traditionally energy systems were analyzed technically, but current environmental issues and considerations have put new constraints on the planning and managing of energy systems. Such an exergoeconomic and exergoenvironmental analysis were born. This analysis is aimed to describe the necessity and application of a new concept in environmental liability accounting based on physical quantities to overcome the weaknesses of the developed allocation methods and the internalization of external environmental damages. The proposed method is modified in environmental analysis to consider the effect of non-energy flows on a macro-surface energy system. As a case study, this method is tuned for a... 

    Energy, Exergy, and exergoeconomic (3E) analysis of gas liquefaction and gas associated liquids recovery co-process based on the mixed fluid cascade refrigeration systems

    , Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 41, Issue 4 , 2022 , Pages 1391-1410 ; 10219986 (ISSN) Norouzi, N ; Bashash Jafarabadi, Z ; Valizadeh, G ; Hemmati, M. H ; Khajehpour, H ; Sharif University of Technology
    Iranian Institute of Research and Development in Chemical Industries  2022
    Abstract
    In this study, energy, exergy, and exergoeconomic analysis is performed on the recent trend of joint production of liquefied natural gas and natural gas liquids based on mixed fluid cascade most important of refrigeration systems. The proposed process is first simulated and exergticly analyzed, and finally, an economic model is used to analyze the exergoeconomic performance. The results include the cost of exergy destruction, exergoeconomic factors, and exergy efficiency. The exergy analysis results show that the proposed process's exergy efficiency is about 53.84%, and the destruction rate is 42618 kW with LNG and NGL production rates of 69.00 kg/s and 27.42 kg/s, respectively. Also,... 

    Exergy Analysis and Optimization of Synthesis Gas

    , M.Sc. Thesis Sharif University of Technology Khavvaji, Davood (Author) ; Farhadi, Fathollah (Supervisor)
    Abstract
    The main purpose of this project is to achieve better design by using exergy analysis. First steam methane reforming process of Tehran refinery is simulated using ASPEN HYSYS. Reformer and high temperature and low temperature shift reactors are simulated using trusted kinetics from literatures and results are compared with plant data and، and there was a good agreement between simulation and plant data. A MATLAB program is written to calculate stream exergies and equipment exergy destruction using AUTOMATION. Streamlined life cycle assessment is done using sustainably metrics، and environmental impacts are evaluated. The main environmental impact was global warming. After exergy destruction... 

    Study of Effective Parameters on Helium Liquefaction Cycle using Exergy Analysis

    , M.Sc. Thesis Sharif University of Technology Eslami, Mahdi (Author) ; Afshin, Hosein (Supervisor)
    Abstract
    Liquefaction of gases is one of the applications of cryogenic science. Among the gases, Helium has the lowest boiling point, which at a pressure of 1atm is approximately 4.2K. Liquid helium can be used to cool superconductors in transportation equipment, military radars, and medical imaging equipment. For helium liquefaction, various cycles are used; these cycles have different parameters in their structure such as of input mass fraction to expanders, heat exchanger effectiveness, expander arrangement and ... which their analysis for improving the performance of the cycle is important. In this research, the aim is to study 2, 3 and 4 expander cycle with various parameters and structure. For... 

    Environmental responsibility accounting in complex energy systems

    , Article Journal of Cleaner Production ; Volume 166 , 2017 , Pages 998-1009 ; 09596526 (ISSN) Khajehpour, H ; Saboohi, Y ; Tsatsaronis, G ; Sharif University of Technology
    Abstract
    Environmental considerations have imposed new restrictions in the planning and management of energy systems. This research aims at describing the necessity and application of a new concept in environmental responsibility accounting. The method is based on physical quantities to overcome the weaknesses of already developed allocation approaches, and to internalize the external environmental damages using the exergy concept. The proposed method is a modification of the exergoenvironmental analysis in order to take into account the effect of non-energy streams in a macro-level energy system. In the proposed method, environmental responsibilities are to be calculated based on the exergy... 

    Simulation and exergy-method analysis of an industrial refrigeration cycle used in NGL recovery units

    , Article International Journal of Energy Research ; Volume 30, Issue 15 , 2006 , Pages 1336-1351 ; 0363907X (ISSN) Mehrpooya, M ; Jarrahian, A ; Pishvaie, M. R ; Sharif University of Technology
    2006
    Abstract
    The behaviour of an industrial refrigeration cycle with refrigerant propane has been investigated by the exergy method. An natural gas liquid recovery unit with its refrigeration cycle has been simulated to prepare the exergy analysis. Using a typical actual work input value; the exergetic efficiency of the refrigeration cycle is determined to be 26.51 % indicating a great potential for improvements. The obtained simulation results reveal that the exergetic efficiencies of the air cooler(s) and chilling sections get the lowest rank among the other compartments of refrigeration cycle. Refrigeration calculations have been carried out through the analysis of T-S and P-H diagrams where... 

    Energy and exergy analyses of an integrated gas turbine thermoacoustic engine

    , Article Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy ; Volume 225, Issue 4 , June , 2011 , Pages 389-402 ; 09576509 (ISSN) Karimi, M ; Ghorbanian, K ; Gholamrezaei, M ; Sharif University of Technology
    2011
    Abstract
    In this article, an attempt is made to utilize the exhaust gases of a small gas turbine to augment power output through the employment of a thermoacoustic system. A simple gas turbine cycle is selected as the base cycle and it is assumed that the thermoacoustic system is powered only by the waste heat of the base gas turbine. A comprehensive cycle analysis of the integrated gas turbine thermoacoustic engine (IGTTE) is carried out from an energy and exergy point of view. Exergy efficiency and internal exergy efficiency are calculated for the different components of the base gas turbine engine as well as the IGTTE. Value and exergy flow diagrams are used to investigate the possible... 

    Multi-objective thermoeconomic optimisation for combined-cycle power plant using particle swarm optimisation and compared with two approaches: An application

    , Article International Journal of Exergy ; Volume 16, Issue 4 , 2015 , Pages 430-463 ; 17428297 (ISSN) Abdalisousan, A ; Fani, M ; Farhanieh, B ; Abbaspour, M ; Sharif University of Technology
    Inderscience Enterprises Ltd  2015
    Abstract
    This paper shows a new possible way with particle swarm optimisation (PSO) to achieve an exergoeconomic optimisation of combinedcycle power plants. The optimisation has been done using a classic exergoeconomic and genetic algorithm, and the effects of using three methods are investigated and compared. The design data of an existing plant is used for the present analysis. Two different objective functions are proposed: One minimises the total cost of production per unit of output, and maximises the total exergetic efficiency. The analysis shows that the total cost of production per unit of output is 2%, 3%and 5% lower and exergy efficiency is 4%, 8% and 6% higher with respect to the base case... 

    Exergy analysis of waste heat recovery section in steam-natural gas reforming process

    , Article Energy and Fuels ; Volume 29, Issue 5 , April , 2015 , Pages 3322-3327 ; 08870624 (ISSN) Shariati, M. H ; Farhadi, F ; Sharif University of Technology
    American Chemical Society  2015
    Abstract
    In this work, an exergy analysis is performed for the waste heat recovery section (WHRS) of the steam-natural gas reforming (SNGR) process as a major energy intensive process. Two alternate conditions are investigated to evaluate the required thermodynamic parameters: normal operating condition and increase of C2+ components in the process feed stream. At normal operating condition, the exergy efficiency of WHRS amounts to 0.58 while some 17.2 kJ energy is destructed for each mole of H2 produced. If heavier than methane components are increased in the feed up to 8.5 mole %, despite the increase of H2 production, the exergy efficiency decreases down to 0.54...