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Consumption criteria and energy labeling of wet cooling towers in Iran
, Article 2009 ASME Power Conference, 21 July 2009 through 23 July 2009 ; 2009 , Pages 153-157 ; 9780791843505 (ISBN) ; Sayyadi, P ; Saidi, M. H ; Sharif University of Technology
Abstract
Increasing concerns about global warming and environmental pollution control has pushed the relevant organizations to set regulations and to develop programs for energy saving. In addition, for many high energy using appliances, energy labeling provides the end user with important data to select energy-efficient equipments and encourage the manufacturers to enhance the performance of their productions. In this research, a new energy-saving program for wet cooling towers has been developed. Considering a thermo-hydraulic analysis, a novel Energy Index (IE) has been extracted which takes all aspects of the problem into account. The present index can be used as a proper criterion for energy...
Reactive absorption in packed bed columns in the presence of magnetic nanoparticles and magnetic field: Modeling and simulation
, Article Journal of Industrial and Engineering Chemistry ; Volume 45 , 2017 , Pages 131-144 ; 1226086X (ISSN) ; Molaei Dehkordi, A ; Sharif University of Technology
Korean Society of Industrial Engineering Chemistry
2017
Abstract
In this article, the influences of ferrofluid and magnetic field on the reactive absorption in packed-bed contactors have been investigated. Because of importance of carbon dioxide emission as a global concern, absorption of carbon dioxide was chosen to investigate these effects. In this regard, multitube approach was applied to model the contactor. The simulation results were validated against experimental data reported in the literature in the absence of nanoparticles and magnetic field and good agreement was obtained. Moreover, influences of various operating conditions on the contactor performance were investigated. It was found that for 3.4 vol.% of magnetic nanoparticles (MNPs), the...
A design procedure for the assessment of carbon capturing and utilization of flue gas from power plant using experimental data
, Article Chemical Engineering Research and Design ; 2017 ; 02638762 (ISSN) ; Avami, A ; Sharif University of Technology
Institution of Chemical Engineers
2017
Abstract
The high dependence of the atmospheric carbon dioxide emissions on fossil fuels has led it to increment. Process design along with the economic aspects, improves the technology diffusion of the carbon capturing. In the pressure swing adsorption as a promising carbon capturing technology, increasing the pressure leads to more adsorbed amount of carbon dioxide and energy consumption of compressor, which is a source for carbon dioxide emission. Experimental data shows that for pressures between 3 to 5bar, the avoided CO2 is in maximum rate. The economic analysis reveals that the pressure of 3bar is appropriate. Also, the utilization of CO2 in the aerogel production, as a nano-based thermal...
Economic and environmental assessment of a solar-assisted ground source heat pump system in a heating-dominated climate
, Article International Journal of Environmental Science and Technology ; 2018 , Pages 1-8 ; 17351472 (ISSN) ; Saidi, M. H ; Abbaspour, M ; Sharif University of Technology
Center for Environmental and Energy Research and Studies
2018
Abstract
In recent years, increasing attention has been paid to the use of renewable energy sources in building sector. The ground source heat pumps are a promising alternative for heating and cooling applications. Despite the high coefficients of performance and significant environmental benefits, their performance may deteriorate over the long-term operation if the annual ground loads are not well balanced. An appropriate solution is the use of hybrid ground source heat pump system through which some portion of the thermal loads can be offset by supplemental components. The aim of this study is to assess the feasibility of a solar-assisted ground source heat pump system for heating a detached house...
A design procedure for the assessment of carbon capturing and utilization of flue gas from power plant using experimental data
, Article Chemical Engineering Research and Design ; Volume 131 , 2018 , Pages 393-405 ; 02638762 (ISSN) ; Avami, A ; Sharif University of Technology
Institution of Chemical Engineers
2018
Abstract
The high dependence of the atmospheric carbon dioxide emissions on fossil fuels has led it to increment. Process design along with the economic aspects, improves the technology diffusion of the carbon capturing. In the pressure swing adsorption as a promising carbon capturing technology, increasing the pressure leads to more adsorbed amount of carbon dioxide and energy consumption of compressor, which is a source for carbon dioxide emission. Experimental data shows that for pressures between 3 to 5 bar, the avoided CO2 is in maximum rate. The economic analysis reveals that the pressure of 3 bar is appropriate. Also, the utilization of CO2 in the aerogel production, as a nano-based thermal...
Comparative assessment of bioethanol supply chain: insights from Iran
, Article Biofuels ; 2018 ; 17597269 (ISSN) ; Avami, A ; Sharif University of Technology
Taylor and Francis Ltd
2018
Abstract
Biofuels are important alternative fuel in recent years. In this work, the bioethanol supply chain planning is performed by BioEnergy Supply Model to optimally find the best pathways using economic and environmental objective functions in Iran. Then, different sustainability criteria focusing on environmental, economic, and social concerns are assessed for possible routes of the bioethanol production from available resources. Although agriculture residues and wastes, decrease the greenhouse gas emissions but municipal solid wastes are more economic and require less water. The agricultural wastes and residues improve the sustainability. Then, criteria focusing on environmental, economic, and...
A hybrid storage-wind virtual power plant (VPP) participation in the electricity markets: A self-scheduling optimization considering price, renewable generation, and electric vehicles uncertainties
, Article Journal of Energy Storage ; Volume 25 , 2019 ; 2352152X (ISSN) ; Ehsan, M ; Mousavizadeh, M ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
The fast growth of technologies most of which depend on natural sources of energy has resulted in a huge consumption of fossil fuels. In this regard, many solutions have been suggested to alleviate the side effects such as air pollution and global warming. Among these solutions, mobile storages like electric vehicles (EVs) and renewable generations, have grown significantly due to being more applicable. But uncoordinated operation and uncertain nature of these distributed energy resources (DERs) can bring forward new challenges and issues to the operators of power system. Thus, in many cases it is more efficient to co-operate them in a hybrid system. In this study, we address a virtual power...
The influence of public R&D and knowledge spillovers on the development of renewable energy sources: The case of the Nordic countries
, Article Technological Forecasting and Social Change ; Volume 146 , 2019 , Pages 450-463 ; 00401625 (ISSN) ; Saboohi, Y ; Arasti, M ; Sharif University of Technology
Elsevier Inc
2019
Abstract
Energy innovation is a key requirement to limit global warming and tackle climate change in the years to come. A better understanding of the public R&D mechanism is likely to improve allocation of resources for energy innovation. Thus, the present paper evaluates the impacts of public R&D and knowledge spillovers on the development of renewable energy sources. To achieve this goal, knowledge flow has been modeled as a function of public R&D expenditures, cumulative knowledge stocks and knowledge spillovers. To show the application of the model, the Nordic countries as one of the pioneers in renewable technologies have been chosen. Results show the cumulative knowledge stock will increase to...
Solar energy systems – Potential of nanofluids
, Article Journal of Molecular Liquids ; Volume 289 , 2019 ; 01677322 (ISSN) ; Hassan, A ; Qasim, M. A ; Ali, H. M ; Babar, H ; Sajid, M. U ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Global warming escalation has extended average temperature of earth beyond its safe limit. To avert this environmental-threat, solar energy has acquired substantial attention of remarkable researchers in this century. To effectively utilize solar energy by transforming into thermal and electrical energy, the involvement of nanofluids having intensified thermal, optical and magnetic properties, has become very popular. The foremost objective of this article is to provide a comprehensive review on the applications of nanofluids in solar energy systems like solar collectors, photovoltaic cells, solar stills, and thermal energy storage, which are thoroughly discussed in this paper. The effect of...
Institutional analysis on impediments over fuel consumption reduction at Iran's transportation niches
, Article Energy Policy ; Volume 129 , 2019 , Pages 861-867 ; 03014215 (ISSN) ; Maleki, A ; Doroudgar Hezaveh, E ; Karimi, M. S ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
The transportation sector is one of the sustainable development wheels that requires a lot of energy to operate, therefore it is concerned as one of the main factors in greenhouse gas emissions and global warming. In Iran, like rest of the world, the light-duty vehicles are the effective factors in the pollution of the metropolitan cities. Although the management of their fuel consumption is a vital action in decreasing the cost and air pollution, that's inextricable link with the public welfare and the economy of the car manufacturers creates barriers. An accurate analysis concerning the barriers to reducing the fuel consumption can be obtained by using the game theory method in the...
Sustainable usage of waste materials as stabilizer in rammed earth structures
, Article Journal of Cleaner Production ; Volume 277 , December , 2020 ; Toufigh, V ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Rammed earth (RE) is an eco-friendly building material and has been capturing special attention among researchers. Many of the recently studied RE additives are extremely resource- and energy-consuming. On the other hand, the usage of fly ash (FA), which is a sustainable replacement for cement, has been scarcely investigated in RE construction. In this paper, an experimental investigation was performed on the physical and mechanical properties of RE materials stabilized with the combination of cement and alkali-activated FA. This scrutiny consists of density measurements, pulse velocity tests, unconfined compression tests, and direct shear tests. Additionally, the carbon dioxide emission and...
Fabrication of durable superhydrophobic surfaces using PDMS and beeswax for drag reduction of internal turbulent flow
, Article Applied Surface Science ; Volume 513 , 2020 ; Liravi, M ; Moosavi, A ; Nouri Borujerdi, A ; Najafkhani, H ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Nowadays, one of the biggest concerns in the world is increasing the CO2 emissions and global warming due to the over-consumption of fossil fuels. In addition, under the intense market competition, the demand for more efficient systems with higher performance and lower energy consumption has escalated. Since the drag force contributes to a considerable percentage of the energy loss and reducing the performance, a large number of studies have been conducted to improve the surface characteristics and, subsequently, declining the drag force. Making the surface superhydrophobic is one of the most effective ways for this purpose. In this work, two different superhydrophobic surfaces using SiO2...
A review on the water-energy nexus for drinking water production from humid air
, Article Renewable and Sustainable Energy Reviews ; Volume 120 , 2020 ; Ghannadi Maragheh, M ; Torab Mostaedi, M ; Torkaman, R ; Asadollahzadeh, M ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
The Supply of sustainable freshwater has turned into a fundamental problem in numerous countries. The increment in population, the industrialization of the world, and variation in global warming temperatures lead to an increase in droughts, storms, and floods around the world. Therefore, the problems of water scarcity appear worldwide. Contrary to popular belief, the largest reserves of water are available in the air. Accordingly, several technologies have been developed for the production of drinking water from humid air in the research works. But, the critical problem is the high energy consumption in this equipment. Therefore, the issues of water-energy nexus are the particular subject in...
Mathematical model for a straight grate iron ore pellet induration process of industrial scale
, Article Computational Materials Science ; Volume 44, Issue 2 , December , 2008 , Pages 296-302 ; 09270256 (ISSN) ; Ferdowsi, A ; Payab, H ; Sharif University of Technology
2008
Abstract
A mathematical model is developed for induration of the iron-ore pellets in an industrial-scale plant based on the laws of mass, heat and momentum transfer. Physicochemical processes occurring during the induration of pellets such as drying of moisture, calcination of limestone and coke-magnetite reaction are considered to evaluate the gradient of temperature within the pellets. Differential equations describing transport phenomena in a grate bed are simultaneously solved by dividing the space in both x- and z- directions and numerically solving the phenomenological equations. A kinetic model is used for estimation of the change of the strength of the pellets due to firing. The model...
CO2 and CH4 diffusivities through synthesized ZIF-8 nanocrystals: an experimental and theoretical investigation
, Article Microporous and Mesoporous Materials ; Volume 324 , 2021 ; 13871811 (ISSN) ; Bastani, D ; Norouzbahari, S ; Ghadimi, A ; Sharif University of Technology
Elsevier B.V
2021
Abstract
CO2 separation is of paramount importance owing to global warming abatement, as well as sour natural gas sweetening. Mixed matrix membranes (MMMs), containing porous zeolitic imidazolate frameworks (ZIFs), in particular ZIF-8, have drawn noticeable attention due to their favorable separation performance. However, there are evidences of discrepancies in the reported values of gas diffusion coefficients/diffusivities through ZIFs, even for common well-studied gases, such as CO2 and CH4 in the literature. These discrepancies might be attributed to the surface/barrier effects, which are intensified by ZIF-8 nanocrystals downsizing. In this paper, an effort has been made to determine the impact...
A novel system for electricity and synthetic natural gas production from captured CO2: Techno-economic evaluation and multi-objective optimization
, Article Journal of CO2 Utilization ; Volume 63 , 2022 ; 22129820 (ISSN) ; Jalili, M ; Ziyaei, M ; Chitsaz, A ; Rosen, M. A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
To mitigate global warming and fossil fuel shortages a novel oxy-fuel combustion power plant integrated with a power to gas system is proposed. A net-zero emission MATIANT cycle with inherent CO2 capture ability is selected as the power cycle also providing the CO2 and power demand of the power to gas system, which comprises a proton exchange membrane electrolyzer for hydrogen production and a Sabatier reactor for methanation. A techno-economic investigation, a multi-objective optimization, and a sensitivity analysis are carried out. A comprehensive economic method that covers all economic aspects is utilized, and a Sabatier reactor model which considers the possibility of the presence of...
Predicting the environmental economic dispatch problem for reducing waste nonrenewable materials via an innovative constraint multi-objective Chimp Optimization Algorithm
, Article Journal of Cleaner Production ; Volume 365 , 2022 ; 09596526 (ISSN) ; Ren, H ; Habibi, M ; Mohammed, K. J ; Khadimallah, M. A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
The usage of conventional fossil fuels has aided fast economic growth while also having negative consequences, such as increased global warming and the destruction of the ecosystem. This paper proposes a novel swarm-based metaheuristic method called Chimp Optimization Algorithm (ChOA) to tackle the environmental, economic dispatch issue and reducing the waste nonrenewable materials. In this regard, two objective functions named fuel cost function and emission cost function are proposed. Unique constrained handling also solves the challenge of multi-objective optimization. Standard IEEE 30 bus with six generators and a 10-unit system are used to demonstrate the usefulness of ChOA. The result...
Thermodynamic analysis and optimization of the organic Rankine and high-temperature Kalina cycles for recovering the waste heat of a bi-fuel engine
, Article Fuel ; Volume 322 , 2022 ; 00162361 (ISSN) ; Moosavi, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Global warming is currently one of the biggest concerns worldwide; hence, addressing this issue is a trending topic among the research community. Escalating global warming through the wasted energy (30% of its input chemical energy) from internal combustion engines (ICEs) by exhaust emission is a major issue that should be considered. One way to reduce the waste of energy from ICEs is to recover the heat using a thermodynamic cycle. Using this method, not only does the engine power increase but also the fuel consumption decreases. Toward this end, and in this study, the organic Rankine cycle (ORC) and high-temperature Kalina cycle (HTKC), which have been previously used for other purposes,...
CO2 storage in carbonate rocks: An experimental and geochemical modeling study
, Article Journal of Geochemical Exploration ; Volume 234 , 2022 ; 03756742 (ISSN) ; Zhao, Y ; An, Z ; Shabani, A ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Carbon dioxide storage in geological formations is one of the mature strategies developed for controlling global warming. This paper represents a comprehensive experimental and geochemical modeling study to analyze CO2-brine-rock interactions in a carbonate rock containing calcite and dolomite minerals. PHREEQC geochemical package has been applied for modeling the geochemical reactions in the studied porous media. Firstly, dynamic experiments are performed to calibrate the geochemical model. Then, static experiments are conducted to study the geochemical reactions in the CO2-brine-rock interaction system. This study contributes to analyzing the precipitation-dissolution and ion exchange...
Investigation of oil recovery and CO2 storage during secondary and tertiary injection of carbonated water in an Iranian carbonate oil reservoir
, Article Journal of Petroleum Science and Engineering ; Volume 137 , 2016 , Pages 134-143 ; 09204105 (ISSN) ; Ayatollahi, S ; Riazi, M ; Sharif University of Technology
Elsevier
Abstract
Gas injection process for more oil recovery and in particular CO2 injection is well-established method to increment oil recovery from underground oil reservoirs. CO2 sequestration which takes place during this enhanced oil recovery (EOR) method has positive impact on reducing the greenhouse gas emission which causes global warming. Direct gas injection into depleted oil reservoirs, encounters several shortcomings such as low volumetric sweep efficiency, early breakthrough (BT) and high risk of gas leakage in naturally fractured carbonate oil reservoirs. Carbonated water injection (CWI) has been recently proposed as an alternative method to alleviate the problems associated with gas...