scholarly journals The Energy and Exergy Analysis of the Reactor Unit of Boric Acid Production Process with ChemCAD Simulation

2022 ◽  
Vol 3 (2) ◽  
pp. 1-6
Author(s):  
Hakan Kızıltaş
Keyword(s):  
Energy Loss ◽  
Boric Acid ◽  
Acid Production ◽  
Fossil Fuels ◽  
Exergy Analysis ◽  
Exergy Efficiency ◽  
Reactor Unit ◽  
Energy And Exergy ◽  
Energy And Exergy Analysis ◽  
Production Facilities

Energy and exergy analysis of systems are of great importance to enhance the energy and exergy efficiency of industrial production facilities. With the energy and exergy analyses performed, the energy dependency of the production facilities and their energy consumption can be reduced, the price of the product can decrease, and the profit margin can increase. Additionally, it is ensured that the energy produced based on fossil fuels is used in a controlled way. In the present study, the analysis of energy and exergy has been performed for the production reactor unit of the Boric Acid from Colemanite. The first law of thermodynamics and ChemCAD simulation program was used for energy analysis calculations, and the calculations of exergy analysis were carried out by using the second law of thermodynamics. The total energy loss of the reactor unit and the calculated energy loss per 100 kcal input steam were calculated as 110880 kcal/h and 3.724%, and the losses of total exergy in the reactor units and the losses of exergy calculated per 100 kcal input steam were calculated as 225058.86 kcal/h and 30.095%, respectively. Exergy efficiency for the reactor unit has been determined as 3.3 %. Some suggestions were given for the reactor units of boric acid production plants to minimize system losses.

scholarly journals Energy and exergy analysis of air based photovoltaic thermal (PVT) collector: a review

2019 ◽  
Vol 9 (1) ◽  
pp. 109 ◽  
Author(s):  
Ahmad Fudholi ◽  
Mariyam Fazleena Musthafa ◽  
Abrar Ridwan ◽  
Rado Yendra ◽  
Ari Pani Desvina ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Flat Plate ◽  
Solar Collector ◽  
Exergy Analysis ◽  
Exergy Efficiency ◽  
Pv Panel ◽  
Energy And Exergy ◽  
Energy And Exergy Analysis ◽  
Flat Plate Solar Collector

<span lang="EN-US">Photovoltaic thermal (PVT) collectors convert solar radiation directly to both electrical and thermal energies. A PVT collector basiccaly combines the functions of a flat plate solar collector and those of a PV panel. This review presents thermodinamics fundamentals, descriptions, and previous works conducted on energy and exergy analysis of air based PVT collector. Studies in 2010 to 2018 of the energy and exergy analysis of air based PVT collectors are summarized. The energy and exergy efficiency of air based PVT collector ranges from 31% to 94% and 8.7% to 18%, respectively. In addition, flat plate solar collector is presented. Studies conducted on air based PVT collectors are reviewed.</span>

scholarly journals Energy and Exergy Analysis of a Coal Fired Power Plant

2018 ◽  
Vol 37 (4) ◽  
pp. 611-624 ◽  
Author(s):  
Sumit Kumar ◽  
Dileep Kumar ◽  
Rizwan Ahmed Memon ◽  
Majid Ali Wassan ◽  
Sikandar Ali Mir
Keyword(s):  
Power Plant ◽  
Energy Loss ◽  
Parametric Study ◽  
Exergy Analysis ◽  
Absolute Error ◽  
Steam Pressure ◽  
Design Parameters ◽  
Energy And Exergy ◽  
Energy And Exergy Analysis ◽  
Main Steam

In this paper, energy and exergy analysis has been conducted on a subcritical coal fired power plant of Wisconsin Power and Light Company, USA to investigate the steam cycle energy and exergy efficiency. The cycle is analyzed by developing a mathematical model using its operating and design parameters. The analysis is performed using EES (Engineering Equation Solver). The energy analysis shows that major share of energy loss occurs in condenser i.e. 72% of total cycle energy loss, whereas, exergy analysis shows that 83.09% total exergy destruction of cycle occurs in boiler.Furthermore, the simulation results are compared with actual with an absolute error of 3.1%. Additionally, the parametric study is performed to examine the effects of various operating parameters such as main steam pressure and temperature, condenser pressure, terminal and drain cooler temperature difference on net power output, energy andexergy efficiency of cycle. The parametric study shows that the plant has maximum energy and exergy efficiencies at steam pressure of 2500psi, condenser pressure of 1.0psi and main steam temperature of 1100oF. Furthermore, these parameters do not seem to change energy and exergy efficiencies significantly.

scholarly journals Energy and Exergy Analysis of a Steam Power Plant in Suda

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Osman Shamet ◽  
Rana Ahmed ◽  
Kamal Nasreldin Abdalla
Keyword(s):  
Power Plant ◽  
Energy Loss ◽  
Heat Loss ◽  
Exergy Analysis ◽  
Primary Objective ◽  
Exergy Destruction ◽  
Steam Power ◽  
Steam Power Plant ◽  
Energy And Exergy ◽  
Energy And Exergy Analysis

In this study, the energy and exergy analysis of Garri 4 power plant in Sudan is presented. The primary objective of this paper is to identify the major source of irreversibilities in the cycle. The equipment of the power plant has been analyzed individually. Values regarding heat loss and exergy destruction have been presented for each equipment. The results confirmed that the condenser was the main source for energy loss (about 67%), while ex­ergy analysis revealed that the boiler contributed to the largest percentage of exergy destruction (about 84.36%) which can be reduced by preheating the inlet water to a sufficient temperature and controlling air to fuel ratio.

scholarly journals ENERGY AND EXERGY ANALYSIS OF A CYLINDRICAL HOT WATER STORAGE TANK: EXPERIMENTAL AND CFD ANALYSIS

2020 ◽  
Author(s):  
Tomas Kropas ◽  
Giedrė Streckienė
Keyword(s):  
Numerical Model ◽  
Storage Tank ◽  
Exergy Analysis ◽  
Water Storage ◽  
Exergy Efficiency ◽  
Hot Water ◽  
Water Storage Tank ◽  
Environment Temperature ◽  
Energy And Exergy ◽  
Energy And Exergy Analysis

Active solar water heating systems typically include hot water storage tanks. The selection of the storage system strongly affects the performance of the entire system. This article presents a detailed analysis of a hot water storage tank during charging and dynamic charging-discharging mode. A numerical model using computational fluid dynamics for the storage tank was developed to investigate the temperature distribution inside of it. Transient thermal analysis was carried using ANSYS Fluent. The numerical model was validated with the experimental results. The energy and exergy analysis as an important tool for the evaluation of the thermal systems quantitatively and qualitatively was performed. The calculation procedures were described. The energy and exergy efficiencies, heat losses were calculated for steady and dynamic processes. Effect of mass flow rate was analysed. The results from parametric analysis showed that charging dynamics reduced the thermocline and efficiency of the hot water storage tank. The dependency of the exergy efficiency of the heat storage tank on the reference environment temperature during the dynamic operation was analysed. Exergy efficiencies for two cities with different climates were compared. This indicated that the higher envi-ronmental temperature gave lower exergy efficiency of the storage tank.

scholarly journals Energy and Exergy Analysis of an Indirect-Mode Natural Convection Solar Dryer for Maize

2021 ◽  
Vol 11 (2) ◽  
pp. 19
Author(s):  
Isaac N. Simate
Keyword(s):  
Natural Convection ◽  
Exergy Analysis ◽  
Exergy Efficiency ◽  
Solar Simulator ◽  
Solar Dryer ◽  
Energy And Exergy ◽  
Energy And Exergy Analysis ◽  
Maize Grain ◽  
Internal Irreversibility ◽  
Drying Chamber

The energy and exergy analysis of an indirect-mode natural convection solar dryer for maize grain is presented. Two different sizes of maize grain bed depths of 0.04 m and 0.02 m translating into grain loads of 10 kg and 5 kg respectively, are used in the study to determine their effects on the collector energy and exergy efficiencies and the drying chamber exergy efficiency. Experiments were carried out using an indirect-mode laboratory solar dryer under a solar simulator with a radiation setting of 634.78 W/m2. The analysis gave average collector energy efficiencies of 33.3 % and 46.2 % for the 10 kg and 5 kg loads, respectively, which are higher than the collector exergy efficiencies of 2.4 % and 2.6 % for the 10 kg and 5 kg loads, respectively. The drying chamber exergy efficiencies are 45.2 % and 28.4 % for the 10 kg and 5 kg loads, respectively. In view of this, the 5 kg load is considered to be more efficient at extracting energy from the collector due to higher air flow resulting from its relatively thin grain bed depth of 0.02 m, but less efficient in utilising the extracted energy to evaporate moisture from the grain which has resulted in a lower drying chamber exergy efficiency. Further, the exergy loss in the drying chamber for the 5 kg load is higher than that in the 10 kg load as 72.3 % of the exergy entering the drying chamber is lost through emissions as well as destroyed through internal irreversibility compared to 57.0 % for the 10 kg load.&nbsp;

Review on Energy and Exergy Analysis of Air and Water Based Photovoltaic Thermal (PVT) Collector

2018 ◽  
Vol 9 (3) ◽  
pp. 1366
Author(s):  
Muslizainun Mustapha ◽  
Ahmad Fudholi ◽  
Chan Hoy Yen ◽  
Mohd Hafidz Ruslan ◽  
Kamaruzzaman Sopian
Keyword(s):  
Thermal Energy ◽  
Energy Demand ◽  
Exergy Analysis ◽  
High Energy ◽  
Exergy Efficiency ◽  
Space Heating ◽  
Domestic Water ◽  
Energy And Exergy ◽  
Water Based ◽  
Energy And Exergy Analysis

<p class="AEuroAbstract">In photovoltaic thermal hybrid (PV/T) collectors, the electricity and thermal energy are produce simultaneously. PV/T technology has been proven in previous studies where it could give benefits for high energy demand supplementary. For example, in space heating, domestic water heating and also drying. The PVT collectors can be classified into air-based PVT, water-based PVT and dual-fluid (air+water) PVT collector. In this paper, the analysis of energy and exergy efficiency of PVT collectors are compiled and reviewed. This study has found that generally the energy and exergy efficiency are range from 40%-70% and 5%-20%, respectively.</p>

scholarly journals Energy and Exergy Analysis of LiBr-aq and LiCl-aq Liquid Desiccant Dehumidification System

2020 ◽  
Vol 14 (1) ◽  
pp. 36-40
Author(s):  
Barış KavasoğullarI ◽  
Ertuğrul Cihan ◽  
Hasan Demir
Keyword(s):  
Exergy Analysis ◽  
Lithium Bromide ◽  
Exergy Efficiency ◽  
Coefficient Of Performance ◽  
Airflow Rate ◽  
Liquid Desiccant ◽  
Energy And Exergy ◽  
Liquid Desiccant Dehumidification ◽  
Energy And Exergy Analysis ◽  
Mass Flow Rates

In this study, energy and exergy analysis of experimental results obtained from a dehumidification system using LiBr-aq (lithium bromide-water) and LiCl-aq (lithium chloridewater) as desiccant was made. In dehumidifier and regenerator columns polycarbonate sheets, which have not been used before, were used as packing material to increase contact area in purposed liquid desiccant dehumidification system. In the analysis, variation of electrical coefficient of performance and exergy efficiency with airflow rate for different solution mass flow rates were investigated. Because of investigation, maximum values of electrical coefficient of performance and exergy efficiency were calculated approximately as 2.8 and 18%, respectively.

scholarly journals Energy and Exergy Analysis of the Air Source Transcritical CO2 Heat Pump Water Heater Using CO2-Based Mixture as Working Fluid

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4470
Author(s):  
Yikai Wang ◽  
Yifan He ◽  
Yulong Song ◽  
Xiang Yin ◽  
Feng Cao ◽  
...  
Keyword(s):  
Exergy Analysis ◽  
Heat Pumps ◽  
Exergy Efficiency ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
Working Fluid ◽  
Domestic Hot Water ◽  
Practical Applications ◽  
Energy And Exergy ◽  
Energy And Exergy Analysis

Given the large demand nowadays for domestic hot water, and its impact on modern building energy consumption, air source transcritical CO2 heat pumps have been extensively adopted for hot water production. Since their system efficiency is limited by significant irreversibility, a CO2-based mixture could offer a promising drop-in technology to overcome this deficiency without increasing system complexity. Although many CO2 blends have been studied in previously published literature, little has been presented about the CO2/R32 mixture. Therefore, a proposed mixture for use in transcritical CO2 heat pumps was analyzed using energy and exergy analysis. Results showed that the coefficient of performance and exergy efficiency variation displayed an “M” shape trend, and the optimal CO2/R32 mixture concentration was determined as 0.9/0.1 with regard to flammability and efficiency. The irreversibility of the throttling valve was reduced from 0.031 to 0.009 kW⋅kW−1 and the total irreversibility reduction was more notable with ambient temperature variation. A case study was also conducted to examine domestic hot water demand during the year. Pure CO2 and the proposed CO2 blend were compared with regard to annual performance factor and annual exergy efficiency, and the findings could provide guidance for practical applications in the future.

scholarly journals An energy and exergy analysis of photovoltaic system in Bantul Regency, Indonesia

2018 ◽  
Vol 9 (1) ◽  
pp. 1
Author(s):  
Arif Rahman Hakim ◽  
Wahyu Tri Handoyo ◽  
Putri Wullandari
Keyword(s):  
Energy Efficiency ◽  
Exergy Analysis ◽  
Environmental Temperature ◽  
Exergy Efficiency ◽  
Photovoltaic System ◽  
Pv System ◽  
High Solar Radiation ◽  
Energy And Exergy ◽  
Energy And Exergy Analysis ◽  
Special Region

Energy and exergy analysis has been conducted on photovoltaic (PV) system in Bantul Regency, a special region of Yogyakarta, Indonesia. The PV exergy analysis was used to determine the performance of the PV system by considering environmental factors other than solar irradiance. This research aims to obtain values of exergy and energy efficiencies in the PV system. The experiment results show that the energy efficiency value produced by the PV system was 8.62–74.18%, meanwhile its exergy efficiency was 0.29%-9.40%, respectively. The value of exergy efficiency is lower than the value of energy efficiency. This result confirmed that the environmental factor greatly affects the output of the PV system. It can be concluded that high solar radiation does not always increase the production of exergy, since it is also influenced by the environmental temperature and the PV cells' temperature.

scholarly journals Modelling of energy and exergy analysis of ORC integrated systems in terms of sustainability by applying artificial neural network

2020 ◽  
Author(s):  
Zafer Utlu ◽  
Mert Tolon ◽  
Arif Karabuga
Keyword(s):  
Neural Network ◽  
Artificial Neural Network ◽  
Solar Energy ◽  
Ambient Temperature ◽  
Exergy Analysis ◽  
Energy System ◽  
Exergy Efficiency ◽  
Energy And Exergy ◽  
Energy And Exergy Analysis ◽  
Artificial Neural

Abstract The present study focuses on the organic Rankine cycle (ORC) integrated into an evacuated tube heat pipe (ETHP), whose systems are an alternative solar energy system to low-efficiency planary collectors. In this work, a detailed thermodynamic and artificial neural network (ANN) analysis was conducted to evaluate the solar energy system. One of the key parameters of sustainable approaches focused on exergy efficiency is application of thermal engineering. In addition to this, sustainable engineering approaches nowadays are a necessity for improving the efficiency of all of the engineering research areas. For this reason, the ANN model is used to forecast different types of energy efficiency problems in thermodynamic literature. The examined system consists of two main parts such as the ETHP system and the ORC system used for thermal energy production. With this system, it is aimed to evaluate energy and exergy analysis results by the ANN method in the case of integrating the ORC system to ETHP, which is one of the planar collectors suitable for the roofs of the buildings. Within the scope of this study, the exergy efficiency was evaluated on the developed ANN algorithm. The effect rates of parameters such as pressure, temperature and ambient temperature affecting the exergy efficiency of ORC integrated ETHP were calculated. Ambient temperature was found to be the most influential parameter on exergy efficiency. The exergy efficiency of the whole system has been calculated as ~23.39%. The most suitable BPNN architecture for this case study is recurrent networks with dampened feedback (Jordan–Elman nets). The success rate of the developed BPNN model is 95.4%.

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