Environmental Impacts and Sustainability
Nima Amani
Abstract
Building insulation stands out as one of the most widely employed strategies to enhance energy efficiency in the building sector. Increasing the thickness of thermal insulation is a conventional approach to meet the design requirements of these structures. In this study, a novel approach to augment the ...
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Building insulation stands out as one of the most widely employed strategies to enhance energy efficiency in the building sector. Increasing the thickness of thermal insulation is a conventional approach to meet the design requirements of these structures. In this study, a novel approach to augment the thermal resistance of external building walls is explored by simultaneously employing multiple thermal insulation materials, comparing this with a single-layer insulation setup. Three typical insulation materials with varying thicknesses are utilized to create a three-layer insulation system, which is applied to a case study involving a house-like cubicle situated in the 3B climate zone per ASHRAE 169-2006. The findings indicate that merely increasing the thickness of a single-layer insulation does not invariably yield optimal solutions. The results emphasize that the consideration of multi-layer insulation systems can establish a continuous decision-making space, enabling the identification of at least one insulation scenario aligned with design requirements. To facilitate designers in the initial stages of thermal insulation design, a rapid and simplified design model has been developed based on the results. The methodology proposed in this study is generalizable and can be applied to all climate zones, offering a comprehensive design tool without the need for intricate calculations.
Environmental Impacts and Sustainability
Amir shasavari; Azadeh Karimi; Morteza Akbari; Mohammad Alizadeh Noughani
Abstract
Rising energy production and consumption, particularly from fossil fuels, pose substantial threats to both global climate and human well-being. Conventional fossil fuel technologies, as primary energy sources in power plants, predominantly generate pollutants during power generation. Conversely, renewable ...
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Rising energy production and consumption, particularly from fossil fuels, pose substantial threats to both global climate and human well-being. Conventional fossil fuel technologies, as primary energy sources in power plants, predominantly generate pollutants during power generation. Conversely, renewable energy technologies are anticipated to contribute to pollution primarily during equipment manufacturing. The combustion of traditional fuels gives rise to significant volumes of greenhouse gases (GHGs) and hazardous substances, leading to escalated costs for individuals and the worldwide populace. External costs attributed to coal-fired power plants range from 4.0 to 9.5 cents per kilowatt-hour, nearly three times higher than those of gas-fired power plants, and multiple times greater than the expenditures linked with renewable energy technologies. The substitution of non-renewable fuels with clean energy sources stands as an efficacious approach to curtailing atmospheric pollution and the concomitant external expenses. On a global scale, an annual savings of up to 230 billion dollars is potentially attainable by achieving a 36% share of clean energy within the global energy mix by 2030. This topic has garnered the attention of policymakers worldwide. Consequently, this study undertakes an examination of the environmental ramifications and social costs associated with diverse energy sources.
Environmental Impacts and Sustainability
Farhad Gholami; Iraj Mirzaee; Mortaza Khalilian
Abstract
Failure Mode and Effects Analysis (FMEA) is utilized for risk appraisal in various domains. In the FMEA methodology, each failure mode is evaluated by considering three risk factors: severity (S), occurrence (O), and detection (D). Subsequently, the Risk Priority Number (RPN) is obtained by multiplying ...
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Failure Mode and Effects Analysis (FMEA) is utilized for risk appraisal in various domains. In the FMEA methodology, each failure mode is evaluated by considering three risk factors: severity (S), occurrence (O), and detection (D). Subsequently, the Risk Priority Number (RPN) is obtained by multiplying these listed factors. This study introduces the Deviation Value Step-Wise Method (DVSM) as a new mathematical model for determining the scores of the SOD factors. This methodology consists of three main steps. Firstly, the FMEA technique is used to identify failure modes. Then, the DVSM is employed to assign weights to the SOD components. In this step, relative importance is determined based on linguistic variables. The third step involves ranking failure modes using the weighted RPN. Two general examples and a case study of two-pipe heat exchanger failure modes are considered to validate the proposed model and test the obtained results. The results demonstrate that the suggested approach has enhanced the overall prioritization of failure modes. This enables the Decision-Maker (DM) to identify primary failure modes and formulate corrective/preventive actions. Finally, both sensitivity analysis and energy efficiency investigation have been performed.
Environmental Impacts and Sustainability
Ali Sayyadi; Mohamad Javad Amiri
Abstract
One of the environmental problems today is the rising land surface temperature and the formation of heat islands in metropolitan areas, which have arisen due to the unplanned expansion of these cities. Satellite imagery is widely used in urban environmental studies to provide an integrated view and reduce ...
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One of the environmental problems today is the rising land surface temperature and the formation of heat islands in metropolitan areas, which have arisen due to the unplanned expansion of these cities. Satellite imagery is widely used in urban environmental studies to provide an integrated view and reduce costs and time. In this study, Landsat satellite imagery in TM, ETM+, and OLI sensors from 1984 to 2020, remote sensing techniques, and GIS is used to analyze the data, and SPSS software is employed to examine the correlation between the data. The results indicate that the land surface temperature in District 1 of Tehran has increased during the last 38 years. Moreover, land use in District 1 has changed significantly over this period, and urban land use increased from 16 % (1984) to 35 % (2020) while vegetation declined from 32 % to 14 %. The results of linear regression analysis show a significant correlation between satellite images and weather station data. The significance coefficient (Sig) in all stations is less than 0.05 with a 95 % confidence interval. Besides, the coefficient of variation (R) for all stations is above 80 %, and the coefficient R2 has a desirable value. The findings suggest that the trend of rising temperatures in District 1 of Tehran has become an environmental problem and the changes in land use such as declining vegetation and increasing the acceleration of urbanization are among the factors that affect it.
Environmental Impacts and Sustainability
Mahdi Pourbafrani; Hossein Ghadamian; Meisam Moghadasi; Masoud Mardani
Abstract
In this research study, a cost-effective and reliable weather station using a microcontroller system containing instruments and sensors for measuring and recording ambient variables was designed, fabricated, and tested. The dataset recorded and stored in the meteorological system can be applied to conduct ...
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In this research study, a cost-effective and reliable weather station using a microcontroller system containing instruments and sensors for measuring and recording ambient variables was designed, fabricated, and tested. The dataset recorded and stored in the meteorological system can be applied to conduct various research in the field of energy and environment, especially in solar systems. Employing a microcontroller system reduces costs and provides special features such as accessing data on the web-based spreadsheets and adding control devices. In this system, meteorological information including solar radiation, air temperature, wind velocity, and air relative humidity is measured and saved in user-defined time intervals such as 30 seconds. The total cost for measuring equipment, sensors, and microcontroller along with a data logger is about 110 USD. To demonstrate the importance of using local meteorological data, in the vicinity of the case studies, the dataset provided by the local weather station was compared with the meteorological data of two nearby national stations for one month. The results revealed that the values reported by the national stations were different from the actual values measured by the local weather station. The deviations for solar radiation, wind velocity, air temperature and humidity values were at least 5, 9, 7%, and more than 100%, respectively.
Environmental Impacts and Sustainability
Mohammad Javad Amiri; Ali Sayyadi
Abstract
The rising temperature of the earth's surface and the formation of heat islands in megacities have become two of the biggest environmental threats. This compound problem affects urban climatology, including urban vegetation and air pollution, human health, and the environment, including the group of ...
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The rising temperature of the earth's surface and the formation of heat islands in megacities have become two of the biggest environmental threats. This compound problem affects urban climatology, including urban vegetation and air pollution, human health, and the environment, including the group of vulnerable members of the society and public health, leading to the growing death rate. Hence, the purpose of this study is to investigate the leading causes of temperature changes and the development of a thermal island in the city of Tehran following the expansion of this metropolis in recent decades. This research uses thermal remote sensing and GIS techniques to analyze information from Landsat satellite images in (TM-ETM-TIRS) sensors from 1984 to 2020. The results of the research indicated that the surface temperature of the city of Tehran during the years 1984 to 1996, 1998 to 2008, and 2010 to 2020 experienced a relative increase in the summer and winter seasons. In the first decade, the average temperature of the green layer was -7, while the temperature of the magenta and red layers were 20 and 25 degrees, respectively. In the second decade, the average temperatures of the green and dark green classes were -1 and 3 while they were 23 and 27 degrees for the magenta and red classes, respectively. In the third decade, the average temperatures of the green and dark green classes were -1 and 3, and thost of the magenta and red layers increased to 28 and 31 degrees, respectively. Furthermore, the analysis of vegetation cover based on the NDVI index pointed to the continuing reduction of vegetation in the studied years. Regarding the direct correlation between the heat island and vegetation and the concentration of the heat island in the city center, further measures must be taken and the vegetation cover should be increased to reduce the heat island. The city center needs to be decentralized as part of the remedy via proper urban design and planning.
Environmental Impacts and Sustainability
Davar Rezakhani; Abdol Hamid Jafari; Mohammad Ali Hajabassi
Abstract
The application of nanomaterials to concrete is an innovative approach to enhance mechanical properties and durability performances. In this work, the addition of a combination of Graphene Oxide Nano-Platelets (GONP) and Ground Granulated Blast Furnace Slag (GGBFS) was studied as admixture in concrete. ...
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The application of nanomaterials to concrete is an innovative approach to enhance mechanical properties and durability performances. In this work, the addition of a combination of Graphene Oxide Nano-Platelets (GONP) and Ground Granulated Blast Furnace Slag (GGBFS) was studied as admixture in concrete. Tests on mechanical and chloride permeation properties were conducted. The results showed that the mix with 0.05 % GONP and the mix with 30 % GGBFS obtained better mechanical strength than the rest of the mixes. The highest electrical resistivity was achieved for the 90-day cured sample with 50 % GGBFS in CONP-free concrete and the 0.01 % GONP in GGBFS-free concrete, which was found to be the most effective in increasing concrete resistance to chloride permeation. The mix with 0.1 w % GONP and 50 w % GGBFS exhibited considerable performance even with other mechanical and durability performances. The addition of 0.1 % graphene oxide and 50 % granular slag increased the compressive strength of the concrete sample by 19.9 % during 28 days and 17.6 % during 90 days compared to the conventional concrete sample. Concrete with a combination of 0.1 % graphene oxide and 50 % granular slag experienced an increase in flexural strength by 15 % during 28 days and 13.6 % during 90 days. A significant reduction in electrical conductivity from 4012C to 1200C was observed for 90-day cured samples containing 0.1 wt % GO and 50 wt % GGBFS compared to the conventional sample. Response Surface Method (RSM) applied to the test data presented an optimized concrete mix containing 0.08 w % GONP and 50 w % GGBFS, the outcome of which was in close agreement with the experimental results.
Environmental Impacts and Sustainability
Alireza Taheri-Rad; Abbas Rohani; Mehdi Khojastehpour
Abstract
Environmental and economic aspects are two remarkable pillars toward a sustainable agro-system. Accordingly, this study aimed to assess the sustainability of autumn rainfed agro-systems in northern Iran by the Eco-Efficiency (EF) indicator. The data of the production processes of wheat, barley, canola, ...
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Environmental and economic aspects are two remarkable pillars toward a sustainable agro-system. Accordingly, this study aimed to assess the sustainability of autumn rainfed agro-systems in northern Iran by the Eco-Efficiency (EF) indicator. The data of the production processes of wheat, barley, canola, and triticale were collected in the three crop years of 2016-2019. Results indicated that the canola production system with 720 kgCO2eq ha-1 had the highest greenhouse gas (GHG) emissions; however, wheat with 604 kgCO2eq ha-1 was attributed to the lowest GHG emissions. The results of the economic analysis also highlighted that the barley production system had the lowest while the canola production system had the highest production costs. The canola production system had the highest profitability, while the barley production system had the lowest in terms of net income and average benefit to cost ratio indicators. The EF indicator for wheat, barley, canola, and triticale was determined to be 1.4, 0.6, 1.8, and 1.1, respectively, indicating the highest EF value for the canola production system.
Environmental Impacts and Sustainability
Abotaleb Bay; Payam Ghorbannezhad; Javad Yazdan Moghadam; Rahim Aali
Abstract
The wastewater treatment of Medium Density Fiberboard (MDF) is a harsh process because of its contents of high suspended solids, chemical oxygen demand, high molecular weight of lignin, and fatty acids. Electrocoagulation (EC) process was used for efficient removal of pollutants and reusing the water. ...
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The wastewater treatment of Medium Density Fiberboard (MDF) is a harsh process because of its contents of high suspended solids, chemical oxygen demand, high molecular weight of lignin, and fatty acids. Electrocoagulation (EC) process was used for efficient removal of pollutants and reusing the water. The impact of aluminum and iron as sacrificial anodes on removal of Chemical Oxygen Demand (COD), Total Suspended Solid (TSS), turbidity, and Total Solid (TS) were investigated. A full quadratic model was deployed to optimize the EC process variables for pretreatment of MDF effluent through response surface methodology. The model results confirmed that the COD and TSS removal efficiency was enhanced upon increasing voltage and residence time; hence, other pollutants initially increased and then, decreased at higher levels. The comparison between aluminum and iron electrodes indicated that the polluted removal efficiencies of aluminum were higher than the iron electrode for MDF wastewater. The optimum values of voltage and residence time for electrocoagulation of MDF wastewater with aluminum were 33 V and 25 min, which resulted in 93 %, 89 %, 67 %, and 76 % for COD, TSS, turbidity, and TS removal, respectively. The implementation of electrocoagulation provided a possibility for reusing water and reducing water consumption in the MDF manufacturing process.
Environmental Impacts and Sustainability
Seyed Saeed Hoseini; Mohammad Amin Sobati
Abstract
The performance characteristics and exhaust emission of a diesel engine using Water Emulsion Fuel (WEF) have been investigated under different engine speeds (1600 to 2400 rpm) and load conditions (25 to 100 %). The experiments were carried out on an air-cooled diesel engine of single cylinder using the ...
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The performance characteristics and exhaust emission of a diesel engine using Water Emulsion Fuel (WEF) have been investigated under different engine speeds (1600 to 2400 rpm) and load conditions (25 to 100 %). The experiments were carried out on an air-cooled diesel engine of single cylinder using the WEF containing 5 % water, 2 % surfactant with Hydrophilic-Lipophilic Balance (HLB) of 6.8. The engine performance and exhaust emission using WEF were also compared with the Neat Diesel Fuel (NDF). According to the results, average reduction of 9.7 % in the engine torque and brake power was observed using WEF at all engine speeds. In addition, a 7.9 % increase in the Brake Specific Fuel Consumption (BSFC) and a 3.7 % increase in the Brake Thermal Efficiency (BTE) were observed for WEF in comparison with NDF in all loading conditions. In case of emission, significant lower hydrocarbon emission (i.e., 14.6 % on average) was observed for WEF comparing to NDF at all engine speeds. Moreover, a considerable reduction in the NOx emission (i.e., 31.1 % on average) was observed for the WEF comparing to the NDF in every engine load. In summary, the application of WEF leads to the reduction in the emission of different pollutants with a positive impact on the environment.
Environmental Impacts and Sustainability
Kazem Kashefi; Alireza Pardakhti; Majid Shafiepour; Azadeh Hemmati
Abstract
Carbon-dioxide Capture and Utilization (CCU) technology is an efficient process in the portfolio of greenhouse gas reduction approaches and is programmed to mitigate global warming. Given that the prime intention of CCU technologies is to prevent CO2 emissions into the atmosphere, it remains to be seen ...
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Carbon-dioxide Capture and Utilization (CCU) technology is an efficient process in the portfolio of greenhouse gas reduction approaches and is programmed to mitigate global warming. Given that the prime intention of CCU technologies is to prevent CO2 emissions into the atmosphere, it remains to be seen if these approaches cause other environmental impacts and consequences. Therefore, the Life Cycle Assessment (LCA) approach was considered to account for all environmental aspects, in addition to the emission of greenhouse gases. In this study, the Life Cycle Inventory (LCI) methodology was employed to quantify the environmental impacts of indirect carbonation of Red Mud (RM), a waste byproduct of alumina production line in Jajarm Alumina Plant, Iran by CO2 exhausted from the plant stacks based on International Organization for Standardizations (ISO) of ISO 14040 and ISO 14044. The results confirmed the reduction of CO2 emission by 82 %. The study of carbon footprint based on ISO 14064 under the criterion of PAS 2050 revealed CO2 emission equivalent to 2.33 kg/ ton RM, proving that CCU managed to mitigate the CO2 emission by 93 % compared to the conventional technology employed in Jajarm Plant, which produced around 34 kg CO2 per 1 ton RM. Furthermore, the economic evaluation of the process brought about 243 $/ton RM in profit via the sales of products including silica, aluminum, hematite, and calcium carbonate. The outcomes of the present study highlight that the intended CCU technology is a practicable approach for large-scale applications.
Environmental Impacts and Sustainability
Ensieh Ozgoli; Younes Noorollahi; Reza Arjmandi; Ali Mohammadi
Abstract
Climate change refers to any significant and long-term alterations in global or regional weather conditions. The impact of climate change on the industrial plans is enormous, while the water supply sector has been challenged to examine how it could continuously operate in the current situation. Optimization ...
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Climate change refers to any significant and long-term alterations in global or regional weather conditions. The impact of climate change on the industrial plans is enormous, while the water supply sector has been challenged to examine how it could continuously operate in the current situation. Optimization of energy consumption and reduction of Greenhouse Gases (GHG) emissions are some of the priorities of water companies. The objective of the study is to propose a novel evaluation approach to the feasibility of using renewable energies (solar, wind, and biomass) in the water and wastewater industry. Tehran Water and Wastewater Company consists of six regional districts and forecasting of its energy consumption, power costs, and carbon tax rates for the next ten years was done by using the regression model. The results indicated that increase in water supply and electricity consumption was evidenced by the increase in Tehran's annual population. GHG emissions were calculated in two scenarios, the first of which is based on the total supply of required electricity from conventional power plants and the second is on the generation of approximately one-third by renewable energies. In addition to the higher emissions of carbon dioxide (CO2) from diesel and oil power plants than the natural gas-fueled plants, by increasing the carbon tax to more than 30 USD per tonne of CO2, it is expected that the emissions will be reduced by 30 % in all fossil-fueled power plant types. Results showed that a small amount of tax was not effective in reducing GHG emissions.
Environmental Impacts and Sustainability
Taraneh Taheri; Mohammad Behshad Shafii; Sourena Sattari; Morteza Khalaji Assadi
Abstract
Combined Heat and Power (CHP) systems have increasingly drawn attention in recent years due to their higher efficiency and lower Greenhouse Gas (GHG) emission. Input-output matrix modeling was considered here as one of the efficient approaches for optimizing these energy networks. In this approach, power ...
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Combined Heat and Power (CHP) systems have increasingly drawn attention in recent years due to their higher efficiency and lower Greenhouse Gas (GHG) emission. Input-output matrix modeling was considered here as one of the efficient approaches for optimizing these energy networks. In this approach, power flow and energy conversion through plant components were modeled by an overall efficiency matrix including dispatch factors and plant component efficiencies. The purpose of this paper is to propose a modification of the objective function presented in some previous studies. This procedure was performed by adding the parameters of plant component lifetime and environmental costs to the objective function. Thus, the optimization problem was formulated by minimizing the total system levelized cost instead of simply hourly energy cost. The study results revealed that producing the electricity by the trigeneration system led to achieving 1256 MWh annual electricity savings that otherwise must be purchased from the grid. The results also showed a significant reduction in annual CO2 emissions (703.31 tons per year). Furthermore, if the price of purchasing CHP electricity was considered three times more than the current ones, payback times would be less than 5 years.
Environmental Impacts and Sustainability
Mohsen Fallah; Zahra Medghalchi
Abstract
In this paper, the thermal performance of four common insulators in two internal and external insulation systems is investigated for the ASHRAE setpoint range by applying detailed numerical simulation and Anti-Insulation phenomenon. Anti-Insulation phenomenon and consequent extra load on the HVAC system ...
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In this paper, the thermal performance of four common insulators in two internal and external insulation systems is investigated for the ASHRAE setpoint range by applying detailed numerical simulation and Anti-Insulation phenomenon. Anti-Insulation phenomenon and consequent extra load on the HVAC system can occur following the thermal insulation of a building if proper temperature setpoint is not selected. In the next step, the proper setpoint is analyzed under simulated building conditions, and all related criteria are studied for this temperature. Also, continuous and intermittent operations of the air conditioning system are investigated. Moreover, the assessment of the environmental benefit of wall insulation is performed by evaluating greenhouse gasses emission payback period and social cost saving. A residential building is simulated in the EnergyPlus software for the case study. Results show that Anti-Insulation occurs approximately at 22 ºC. Both external and internal insulations lead to a significant reduction in energy consumption. Nevertheless, the external insulation shows a bit more reduction. Intermittent operation outperforms the continuous operation by 8 % on average. The insulator’s production phase is considered in the analysis of the insulation environmental benefits. Results show that, in this case, the prioritization of insulators would be different from that case in which this process is not considered. According to results, in terms of social costs, applying thermal insulation to residential buildings is necessary.
Environmental Impacts and Sustainability
Roya Pashangpour; Faramarz Faghihi; Soodabeh Soleymani; Hassan Moradi CheshmehBeigi
Abstract
There has been a global effort to reduce the amount of greenhouse gas emissions. In an electric resource scheduling, emission dispatch and load economic dispatch problems should be considered. Using renewable energy resources (RESs), especially wind and solar, can be effective in cutting back emissions ...
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There has been a global effort to reduce the amount of greenhouse gas emissions. In an electric resource scheduling, emission dispatch and load economic dispatch problems should be considered. Using renewable energy resources (RESs), especially wind and solar, can be effective in cutting back emissions associated with power system. Further, the application of electric vehicles (EV) capable of being connected to power grid reduces the pollution level in the transportation sector. This paper investigates a resource scheduling with uncertain behavior of RESs and EVs by considering the penalty factors of emission for each conventional power plant in Hormozgan province of Iran for a 10-year period from 2016 to 2026. In this study, combined-cycle and thermal units are also taken into account. The CPLEX Solver is utilized for resource scheduling problem in GAMS. For combined-cycle power plants, ramp rate constraints are also included. To investigate the impact of uncertainties, different scenarios are considered. The obtained results demonstrate that Hormozgan province has a decent potential of utilizing RESs and EVs to achieve pollution reduction and optimal cost.
Environmental Impacts and Sustainability
Hasan Hekmatnia; Ahmad Fatahi Ardakani; Armin Mashayekhan; Morteza Akbari
Abstract
As a key economic element, energy plays an important role in the development of societies. Economic growth and its urgent need for energy highlight the need for optimal energy use. Wind energy is an energy source that has become an increasingly common source of electricity. In this study, socio-economic ...
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As a key economic element, energy plays an important role in the development of societies. Economic growth and its urgent need for energy highlight the need for optimal energy use. Wind energy is an energy source that has become an increasingly common source of electricity. In this study, socio-economic impacts of the cost of electricity generated by wind power plants were assessed with Iran as the focus of this study. The environmental impacts of wind energy were also considered by reviewing and analyzing research papers. Studies showed that although the use of wind energy in Iran began in Manjil in northern Iran, no significant progress has been made in this field despite all the efforts over the past years. The results indicated that the initial cost of launching wind turbines was the most important factor in the failure of this technology. The costs of purchasing turbines, construction of roads, provision of electrical infrastructure, project management, installation of turbines, insurance premiums, grid connections, and power lines were shown to affect costs of energy production. Furthermore, operation and maintenance costs, the choice of installation location, increasing production capacity, expansion of the energy market, and policies in the country can play an essential role in determining the cost of wind energy production. Given that power generation using wind turbines are economical, it is recommended that turbines be installed in suitable windy locations. In addition, considering that one of the crises facing the world and especially Iran is environmental pollution, utilizing energies such as wind energy for generating electricity is advised due to their lower pollutant emissions and lower economic and social costs.
Environmental Impacts and Sustainability
Mohammad Hossein Jahangir; Mahnaz Abolghasemi; Seyedeh Mahsa Mousavi Reineh
Abstract
Drought is considered as a destructive disaster that can have irreversible effects on different aspects of life. In this study, artificial neural network was used as a powerful means of modeling nonlinear and indefinite processes in order to simulate drought intensities at 7 synoptic stations of Khorasan ...
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Drought is considered as a destructive disaster that can have irreversible effects on different aspects of life. In this study, artificial neural network was used as a powerful means of modeling nonlinear and indefinite processes in order to simulate drought intensities at 7 synoptic stations of Khorasan Razavi from more than 35 years ago up to the year 2014. Input data were the calculations of the two indicators of PNPI and SPI by DIC software, and the output layer (drought intensity) was taken to the Matlab software and employed as the teaching data (from 25 years), experiment (from 5 years), and validation (from another 5 years). The 3-9-1 structure of the network of layers had the maximum accuracy with the error rate of less than 2 % and high correlation (more than 90 %). After trial and error for each station through sigmoid stimulation function in the Perceptron network, it was observed that the stations of Mashhad and Quchan had the minimum error and the maximum error was related to the station of Neyshabur. The results of comparisons and observations showed that the artificial neural network had high efficiency in simulation of the data. The obtained correlation amount of 0.999 for the base station represented the small error of the model in prediction. Drought forecasting was performed in this study by the trained algorithm in the artificial neural network without using the observation data. The results showed that rainfall, temperature, and speed models had a positive role in forecasting the provinces that would experience drought. Due to its lower amount of error, SPI indicator was selected for mapping, the findings of which showed that the highest drought intensity belonged to the near normal to normal wet lands.
Environmental Impacts and Sustainability
Bahram Hosseinzadeh Samani; Marziyeh Ansari Samani; Rahim Ebrahimi; Zahra Esmaeili; Ali Ansari Ardali
Abstract
Due to limited oil reserves, the rising world fuel prices and environmental problems caused by the use of fossil fuels increase the tendency to use alternative fuels such as biodiesel and bioethanol. In this study, the evaluation of energy and exergy flow from seed planting to final production of biodiesel ...
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Due to limited oil reserves, the rising world fuel prices and environmental problems caused by the use of fossil fuels increase the tendency to use alternative fuels such as biodiesel and bioethanol. In this study, the evaluation of energy and exergy flow from seed planting to final production of biodiesel from rapeseed oil was carried out. Biodiesel production from rapeseed was made in three main phases: farm, oil extraction, and industrial biodiesel production. Initially, the input and output variables for rapeseed production were collected through questionnaires from 30 rapeseed farms in Khuzestan province, Iran. Thus, the amount of energy input and output to the field for rapeseed was estimated to be 12826.98 and 22195 MJ/ha, respectively. The highest energy consumption is related to chemical fertilizers with 65 % share of other inputs. Input and output exergy rates were obtained as 3933.494 and 22603.39 MJ/ha, respectively, and the highest exergy consumption related to diesel fuel with 58 % share of other inputs. At the biodiesel production stage, the input energy and output energy were 156.95 MJ and 41.88 MJ, respectively, and the highest amount of electricity consumed was 91.02 MJ. The total amount of exergy in the production of biodiesel and the output exergy was 48.412 MJ and 64.568 MJ, respectively. In this study, the effects of alcohol-to-oil molar ratio, ultrasound power (W), catalyst concentration (w/w %), and the reaction time (min) on methyl ester yield using response surface methodology based on Box Behnken experimental design in the Design Expert software were investigated. Finally, gas emissions were studied at the planting and biodiesel production stages, and the resultsshowed that the highest greenhouse gas emissions at the planting stage were related to chemical fertilizers and alcohol production.
Environmental Impacts and Sustainability
Marziyeh Forootan; Bahram Hosseinzadeh Samani; Amin Lotfalian; Sajad Rostami; Zahra Esmaeili; Marziyeh Ansari Samani
Abstract
To preserve fossil fuel sources and reduce environmental pollution, it is necessary to use higher quality and more efficient fuels that cause lower pollution and are recovered more easily. Therefore, this study will investigate the cycle of biodiesel production from chicken fat by life-cycle assessment ...
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To preserve fossil fuel sources and reduce environmental pollution, it is necessary to use higher quality and more efficient fuels that cause lower pollution and are recovered more easily. Therefore, this study will investigate the cycle of biodiesel production from chicken fat by life-cycle assessment (LCA). To achieve this purpose, information on the amount of inputs consumed and produced by some broiler-farming units was collected using questionnaire. The value of net energy in this cycle was assessed to be a large negative number, and the energy ratio lower than one indicates high energy consumption of the production of this fuel. The net yield of biodiesel production was 0.574 liter-biodiesel per kg of waste fat. In the cycle, the greatest impact of pollutants was exerted on the Marine aquatic ecotoxicity intoxication and the least effect on ozone depletion. According to the global warming index, production of 1 liter of biodiesel yielded 1.90 kg CO2, and the depletion rate of fossil fuel sources for the production of 1 liter of biodiesel was obtained 21.35 MJ. The production of biodiesel from chicken slaughterhouse waste fat is considered a kind of energy recycling and is an effort to reduce environmental pollution.
Environmental Impacts and Sustainability
Laleh R. Kalankesh; Mohammad Ali Zazouli; Ahmad Mansouri
Abstract
Water scarcity is a critical issue in Caspian Sea regions of Iran. Thus, people may use polluted water or saline brackish groundwater, estuarine water or seawater. This paper deals with the application of Low-Pressure reverse osmosis (RO) for removing salt and Total Organic Carbon (TOC) in synthetic ...
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Water scarcity is a critical issue in Caspian Sea regions of Iran. Thus, people may use polluted water or saline brackish groundwater, estuarine water or seawater. This paper deals with the application of Low-Pressure reverse osmosis (RO) for removing salt and Total Organic Carbon (TOC) in synthetic and Caspian Sea waters. The study aims to achieve optimization at different pressures (30, 50, 70, and 90 PSI) with synthetic seawater at initial salt concentrations (5, 25, and 35 g/L TDS) at various retention time intervals (15, 30, 60, 90, and 120 minutes). The results showed that the low-pressure RO system was able to reject 95 %, 57 %, and 46 % of 5, 25, and 35 g/L of TDS from synthetic seawater. In addition, rejection efficiency was achieved at 86 % and 78 % for Caspian seawater and Tajan River, respectively. In addition, optimal conditions (pressure: 70 PSI, time: 120 min) for salt rejection included 16-23 %, 93-94, 52-56 %, 88-90, and 22 % for 35g/L TDS, Tajan River, 5g/L TDS, 25g/L TDS, and Caspian seawater, respectively. Moreover, TOC rejection was achieved at >95 % and >97 % of Tajan River and Caspian seawater, respectively, at an overall 120-minute interval. In the case of growing environmental pollution that is discharged into Caspian sea including industrial and agricultural effluents from rivers, this study proposed the suggested pilot as a simple design that will significantly reduce salt, TOC, and TDS.
Environmental Impacts and Sustainability
Mohammad Ameri; Keivan Salimi
Abstract
In recent decades, excessive using fossil fuels has been resulted in emitting greenhouse gases such as CO2, consequently, environmental pollution. In this study, the techno-economic analysis of the CCHP/PV hybrid system application for a sample building was examined to reduce the environmental pollution ...
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In recent decades, excessive using fossil fuels has been resulted in emitting greenhouse gases such as CO2, consequently, environmental pollution. In this study, the techno-economic analysis of the CCHP/PV hybrid system application for a sample building was examined to reduce the environmental pollution and primary energy consumption of the buildings. The life-cycle cost analysis was utilized as a robust economic criterion. To investigate the effect of climate conditions on the system performance, five cities of Bandar Abbas, Ahvaz, Tehran, Bandar Anzali, and Ardebil were considered and evaluated. The results showed that the pollution emission rate and primary energy consumption of the building were declined by the CCHP/PV system up to 10.14 % and 26.52 % for the coldest climates, respectively. Moreover, an increase of 33.33 % was observed compared to the conventional system due to its high initial investment. However, the sensitivity analysis of energy tariffs, as well as equipment prices indicated favorable results and a bright horizon for these systems.
Environmental Impacts and Sustainability
Sepideh Abedia; Fatemeh Razi Astaraiea; Barat Ghobadian; Omid Tavakoli; Hassan Jalili
Abstract
Nowadays, the replacement of renewable energies such as biofuels is one of the main priorities in environmental programming and investments. This study is based on sustainable strategy towards integrating algal biomass generation as a green feedstock with wastewater treatment, CO2 bio-fixation, and bioenergy ...
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Nowadays, the replacement of renewable energies such as biofuels is one of the main priorities in environmental programming and investments. This study is based on sustainable strategy towards integrating algal biomass generation as a green feedstock with wastewater treatment, CO2 bio-fixation, and bioenergy production. Therefore, the performance of Trichormus variabilis in biomass production together with ammonium and phosphate removal from an actual effluent obtained from a mixed wastewater streams has been investigated using two mixing methods under aeration and agitation conditions. Dilutions of 10 %, 20 %, 40 %, 60 %, 90 % and 100 % (v/v) were used for growth evaluation. The results showed that the bubbled air effectively enhances the biomass productivity. However, the agitation system was suggested to cultivate the algae in the wastewater due to the elimination of possible mechanical stimulation stress on cells. Moreover, high pH levels (pH>8) indicated a negative inhibitory effect on growth. Thus, unexpected inhibitory impacts were removed through providing the wastewater dilutions mixed with BG11 culture medium, which contains essential required nutrients, to support the algal growth in the wastewater, adjust pH and remove the mechanical stress induced by bubbling compressed air. The results with respect to investigating the effect of the inoculums and wastewater concentrations on the biomass production suggested that the highest biomass generates with 30 mg.mL-1 inoculum in 40 % mixed wastewater diluted by the BG11 medium having the highest potential in CO2 bio-fixation of 9.19±0.64 g.L-1. The results of the wastewater analysis demonstrated the removal potential of ~43 % and ~75 % for NH4+ and PO43−, respectively. The generated biomass after phycoremediation and CO2 bio-fixation can be effectively utilized in different types of biofuel production.
