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    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  

    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,... 

    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 analysis of a gas turbine power plant with inlet evaporating cooling systems

    , Article 23rd International Conference on Efficiency, Cost, Optimization, Simulation, and Environmental Impact of Energy Systems, 14 June 2010 through 17 June 2010 ; Volume 4 , 2010 , Pages 203-210 ; 9781456303181 (ISBN) Ameri, M ; Karimi, M ; Ahmadi, P ; Ecole Polytechnique Federale de Lausanne; Schweizerische Eidgenossenschaft ; Sharif University of Technology
    Aabo Akademi University 
    Abstract
    The gas turbine (GT) is known to feature low capital cost to power ratio, high flexibility, high reliability without complexity, short delivery time, early commissioning and commercial operation and fast starting-accelerating. Hence, researchers all over the world are working to increase the output power and efficiency of gas turbine cycle. One of the important techniques to increase the output power of such cycles is the compressor inlet air cooling method. The objective of this paper is to analysis the gas turbine cycle from both energy and exergy point of view. Thus, two important methods for increasing the output power, i.e. fog and media inlet air cooling systems are discussed.... 

    Thermodynamic and thermoeconomic analysis of a novel combined cooling and power (CCP) cycle

    , Article Applied Thermal Engineering ; Volume 139 , 2018 , Pages 474-487 ; 13594311 (ISSN) Rostamzadeh, H ; Ghaebi, H ; Parikhani, T ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    A new combined cooling and power (CCP) cycle is proposed by a novel combination of the Kalina cycle (KC) and ejector refrigeration cycle (ERC) to produce simultaneous power output and cooling output. The exhaust of the turbine is fed to the ejector as a primary flow to draw the secondary flow (outlet of the evaporator) into the ejector. Energy, exergy, and exergoeconomic analysis of the proposed cycle are carried out leading to determine the first-law-efficiency, the second-law-efficiency, the sum unit cost of the product (SUCP) of the system, and the main source of the irreversibility. The thermal efficiency, exergy efficiency, overall exergy destruction rate, SUCP of the system, net... 

    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... 

    Analysis of Chemical Looping Combustion (CLC)Systems Combined with CO2 Separation

    , M.Sc. Thesis Sharif University of Technology Motevally, Rohollah (Author) ; Soltanieh, Mohammad (Supervisor) ; Panjeshahi, Mohammad Hassan (Supervisor)
    Abstract
    One of the most important environmental problem across the world is global warming due to increase in greenhouse gas concentration in atmosphere. The main objective of this thesis is to try to find some ways that lead to stop or decrease, increasing trend in greenhouse gas emission, espicialy CO2. The investigation of the sources of emission of CO2 and proposed methods to decrease the rate of the emission, reveals that sepration of CO¬2 from combustion products and its storage is the only promising solution of this problem. The common feature of all propsed methods for elimination of CO¬¬2 from combustion gas, is the presence of a separation step. The addition of this separation step to... 

    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... 

    Exergy and Thermoeconomic Analysis of a Hybrid System of Desalination and CCHP, Augmented by Solar Energy

    , Ph.D. Dissertation Sharif University of Technology Saraei, Alireza (Author) ; Abbaspour Tehrani Fard, Majid (Supervisor)
    Abstract
    The demand in water and energy for household, industrial and agricultural uses continue to grow. In recent years, many researches have been done on thermodynamic assessment and optimization of Combined Cooling, Heating and Power (CCHP) and desalination systems. The interesting and important point is the potential of combining CCHP and desalination systems by employing the solar power. The purpose of this study is exergy analysis and thermoeconomic optimization of a hybrid system of Multi-Effects Distillation desalination (MED) and CCHP, augmented by solar energy. The thermoeconomic analysis is carried out by Total Revenue Requirement (TRR) method. Properties of working fluid in hybrid MED... 

    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  

    Flare Gas Recovery and Transforming Them into Petrochemicals

    , M.Sc. Thesis Sharif University of Technology Khodabandeh Jahromi, Maryam (Author) ; Sattari, Sourena (Supervisor)
    Abstract
    By combustion, waste toxic, flammable and corrosive materials are changed to less inviromental problems by combustion. It also creats environmental problems (the most serios problem is caused by burning gases), as well as economic resources are wasted. So several ways was investigated to reduce combustion gases. Mini-methanol plant is one of varios possible ways that can convert these gases in to methanol. So methanol plant was simulated and then pinch analysis was performed on the simulated plant. Performing of pinch analysis caused 94.5 percent and 25 percent reduction in amaunt of hot and cold utility respectively. Before and after pinch analysis, the exergy analysis was performed on... 

    Technical and Economical Feasibility Study of Applying Heat Pump Systems to Provide Utilities for Oil & Gas Industries

    , M.Sc. Thesis Sharif University of Technology Hamidzadeh, Zeinab (Author) ; Sattari, Sorena (Supervisor) ; Amidpour, Majid (Supervisor)
    Abstract
    Distillation is the most applied unit in the separation processess of the oil and gas industries. Because the distillation process requires energy in the form of the utilities, integration of heat pump systems in the distillation process as an application of these systems is considered in this research. A new and effective methodology of proper integrating of heat pump and distillation columns has been proposed by collecting thermodynamic and thermoeconomic tools. Then, this procedure has been applied on the ethane recovery and NGL fractionation units of 4 & 5 phases of the south pars field. The exergy analysis of the distillation columns is the first step of this methodology as the... 

    Exergy Analysis of Thermoacoustic Heat Pump with Industrial Application

    , Ph.D. Dissertation Sharif University of Technology Karimi, Mohsen (Author) ; Ghorbanian, Kaveh (Supervisor)
    Abstract
    Typical thermoacoustic systems deal with the conversion of heat energy to sound energy and vice versa. Recent advances in the field of thermoacoustics have altered the working mechanism of many conventional heating and cooling devices. These systems have three highlighted advantages: first, they have simple structure, no moving parts, low cost of manufacture, and high reliability; second, by using inert gases as working fluid, they are environmentally friendly; and finally, heat driven thermoacoustic devices can be driven by low quality energy sources such as waste heat and solar energy.
    The main focus of the present thesis is on the application of the thermoacoustic technology in the... 

    Determination of Parabolic Trough Solar Collector Efficiency Using Al2O3/Synthetic Oil Nanofluid: A Comprehensive Numerical Study with The Effect of Wind Velocity

    , Ph.D. Dissertation Sharif University of Technology Khakrah, Hamid Reza (Author) ; Shamloo, Amir (Supervisor) ; Kazemzadeh Hannani, Siamak (Supervisor)
    Abstract
    Due to significant reduction in fossil fuel sources; several researches have been conducted recently to explore modern sources of renewable energy. One of the major fields in the category of renewable energy harnessing devices is parabolic trough solar collectors (PTC). Several parameters have effect on the overall efficiency of the PTC’s.As the effect of these parameters is coupled to each other, a comprehensive investigation is necessary.In the present study a numerical analysis is performed to examine the efficiency of PTCs via variation of several governing parameters (e.g. wind velocity magnitude, nanoparticles volume fraction, inlet temperature and reflector’s orientation). A detailed... 

    Exergy Loss Evaluation in a Combined Heat and Power Cycle in a South Pars Gas Refinery

    , M.Sc. Thesis Sharif University of Technology Babaye Khorasani, Firoozeh (Author) ; Farhadi, Fatollah (Supervisor)
    Abstract
    In this thesis the replacement of separate heat and power production with combined heat and power system in South Pars Gas Refinery is investigated. High Exergy loss is associated with conventional concept of Heat and power generation. Alternative methods for combined heat and power (CHP) production are investigated and four different technologies are proposed: 1) process steam production by HRSG, 2) power production by condensing steam turbine, 3) CHP production by non-condensing steam turbine, and 4) CHP production by condensing steam turbine. Energy and exergy efficiency and profitability of these technologies are compared with separate heat and power production. The result shows that... 

    Exergy Analysis of Turbochargen Systems in the Internal Combustion Engines

    , M.Sc. Thesis Sharif University of Technology Goudarzi, Amir (Author) ; Mozafari, Ali Asghar (Supervisor) ; Ali Ehiaee, Mahdi (Supervisor)
    Abstract
    Thermodynamic analysis of a system is a method for recognizing the type of energy transmission between system and surrounding environment. It also helps to find how macroscopic properties of the system change during this process. This analysis is based on first and second laws of thermodynamic. The first law expresses conservation of energy and inspects quantity of energy transmission but doesn’t evaluate quality of energy. The second law expresses quality of energy and the ability of doing work. The analysis that uses both of the laws is named exergy analysis. By exergy analysis the place of useful energy losses in the system can be determined. In this research the exergy analysis of...