Seyed Hossein Hashemi; Mojdeh Rezvani; Mahdi Mohammadi
Abstract
Introduction: Due to the growth and development of new types of communication and information technologies around the world, the use of digital services is widely increasing and our country, Iran, is no exception to this rule. Information technology and digital services industries consume significant ...
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Introduction: Due to the growth and development of new types of communication and information technologies around the world, the use of digital services is widely increasing and our country, Iran, is no exception to this rule. Information technology and digital services industries consume significant amounts of energy in various forms as well as in various sectors such as production, distribution and use of relevant equipment and services and as a result, produce various pollutants, including greenhouse gases, and release them into the environment. Therefore, the purpose of this study is to investigate the eco-friendliness of digital services and IT industry of Iran in the web hosting and cloud services sectors through evaluating North-west data center of Iran as a representative of the IT industry of Iran in the web hosting and cloud services sectors.Material and methods: For this purpose, in this study, first the effective aspects of information technology on the environment as well as the environmental standards related to data centers were identified through library studies and review of existing domestic and foreign literatures and after that, 8 servers of “Iran Server” were investigated. In the next step, after estimating the amount of energy consumed and carbon dioxide produced by North-west data center of Iran (which has 319 active servers), the efficiency and environmental compatibility metrics of this data center were calculated and finally, by analyzing and summarizing the obtained results, eco-friendliness of North-west data center of Iran as a representative of IT industry of Iran in the web hosting and cloud services sectors, was investigated.Results and discussion: The results of energy consumption and pollutants production of North-west data center of Iran indicate that this data center consumes an average of 185.16 MWh of electricity per month, and followed by that produces 533.26 tons of carbon dioxide per month. Also, the values of Carbon Usage Effectiveness (CUE), Power Usage Effectiveness (PUE) and Energy Reuse Effectiveness (ERE) metrics in this data center respectively equivalent to 2.88 (kg CO2 per kilowatt hour), 4.03 and 4.03 and also the values of Energy Reuse Factor (ERF) and Green Energy Coefficient (GEC) are zero. These values indicate that the energy consumption of Iran's data centers is supplied from non-renewable energy sources and this energy is finally released in the form of excess heat in the environment after consumption in different sectors, which emits a large amount of greenhouse gases including CO2 in the environment And inflicts numerous and irreparable damages on the environment such as air pollution, global warming, climate change, etc. Conclusion: A general summary of the information obtained from the study of various aspects of eco-friendliness of North-west data center of Iran as a representative of IT industry of Iran in the web hosting and cloud services sectors and its comparison with other green data centers in the world shows, this data center has not met the necessary metrics to comply with environmental standards related to green or eco-friendly data centers and as a result is not very compatible with the environment and is far from other green data centers in the world.
Asadollah Akram; Majid Khanali; Mahdieh Mohammadnia Galeshklamei; Homa Hosseinzadeh-Bandbafha
Abstract
Introduction: Sustainable development necessitates the supply of energy resources in a sustainable manner, with a reasonable cost and with minimum negative social and environmental impacts. Thus the optimization of energy consumption, and as a result, the reduction of environmental emissions is of particular ...
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Introduction: Sustainable development necessitates the supply of energy resources in a sustainable manner, with a reasonable cost and with minimum negative social and environmental impacts. Thus the optimization of energy consumption, and as a result, the reduction of environmental emissions is of particular importance. The purpose of this study was to assess the amounts of consumed energy and pollutant emissions, optimization of energy consumption, and reduction in environmental emissions in the cake production industry in Guilan Province using data envelopment analysis (DEA) and genetic algorithm (GA). Material and methods: The efficient and inefficient units considering energy consumption were identified using DEA models. The optimal energy consumption pattern based on efficient units was presented for other cake production units, and the environmental assessment was performed based on the optimal pattern. Finally, using the multi-objective genetic algorithm (MOGA) and considering two objective functions aiming at increasing the yield and reducing the global warming (GW) index, the optimal energy consumption pattern in cake production units was presented. Results and discussion: The results of this study showed that 260532.25 MJ of energy was consumed for a daily production of 4157.14 kg of cake. The highest share of energy consumption was allocated to natural gas with 128582.1 MJ. Also, GW index was calculated 13099.49 kg CO2 eq. per ton of produced cake.According to DEA results, from a total of 21 cake production units, 17 units were recognized efficient based on variable returns to scale model. Based on DEA results, the total energy consumption for optimum consumption of inputs, the energy saving percentage, and the reduction of GW index were determined 254929.28 MJ day-1, 2.15%, and 550.18 kg CO2 eq. per ton of produced cake, respectively. Also, the energy use pattern proposed by the MOGA resulted in 36.3% reduction of energy consumption, in which the highest percentage of energy savings was associated with human labor. Based on the optimization results of MOGA, GW index for production of one ton of cake was calculated 10038.44 kg CO2 eq. Conclusion: MOGA optimization method in comparison to DEA, resulted in more reduction of energy consumption, GW index, production costs, and environmental burdens as well as higher income. Thus, the use of MOGA will pave the way for achieving sustainable development in cake production industry and staying in competition with other food industries.
Pooya Arbab; Bita Ayati; Mohammad Reza Ansari
Volume 16, Issue 3 , October 2018, , Pages 119-134
Abstract
Introduction:
Many pollutants in industrial wastewaters, such as dyes, can't be removed easily by the conventional physical, biological and chemical purification processes, because of their complexity and intractability. Therefore, it is necessary to find an effective treatment technology that can degrade ...
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Introduction:
Many pollutants in industrial wastewaters, such as dyes, can't be removed easily by the conventional physical, biological and chemical purification processes, because of their complexity and intractability. Therefore, it is necessary to find an effective treatment technology that can degrade complex bio-refractory molecules or can breakdown them into smaller molecules which can be further degraded by conventional methods. Cavitation is one such recent technique which has been extensively studied for the treatment of complex wastewater due to its ability of generating highly reactive free radicals. Hydrodynamic cavitation has a potential of application on larger scale due to its capability in generating hydroxyl radicals at ambient condition, easy scale up and less material cost making it more economical to employ. The purpose of this study was application of hydrodynamic cavitation process for removing Reactive Black 5 and optimization the affecting parameters (pH, inlet pressure, hole diameter and initial concentration of dye) based on the amount of efficiency and energy consumption.
Material and methods:
In this research, removal of Reactive Black 5 with the use of hydrodynamic cavitation process was studied. 8.25 liters of colored solution was examined in each test. The cavitation was produced by orifice plate and pump. In order to optimize process, various trials were performed in pH of 3 to 11 and also using different orifice plates with hole diameter of 2, 3, 5 and 7 mm at inlet pressures of 2, 3, 4 and 5 bar and dye concentration of 30, 50 and 100 ppm. Due to the constant voltage of urban electricity, the electric current was measured as an indicator of energy consumption by ammeter.
Results and discussion:
According to the results by reducing the pH, dye removal was increased and orifice plates with larger hole diameter in upper pressures had better efficiency. It was observed that increasing the initial concentration of dye resulted in decreasing dye removal efficiency. The orifice with 7 mm hole diameter at 5 bar inlet pressure yielded the highest efficiency, but by involving the amount of energy consumed and considering the process efficiency to energy consumption, the orifice with 7 mm hole diameter at 4 bar inlet pressure was chosen as the best. The pH of 3, orifice with 7 mm hole diameter at 4 bar pressure and initial concentration of 30 ppm (with regards to pump energy consumption obtained from measuring the electrical current and the efficiency of process) were selected as optimum conditions. In these conditions after 120 minutes, 38.21% dye removal was obtained using hydrodynamic cavitation.
Conclusion:
Hydrodynamic cavitation has a potential of application on larger scale due to its capability in generating hydroxyl radicals at ambient condition. It was found that the energy consumption was an effective factor in selecting the optimum conditions. By reducing the initial dye concentration and pH, dye removal was increased and orifice plates with larger hole diameter in upper pressures had better efficiency.
Vida Varahrami; Morteza Tahamypur; zahra haqi
Volume 14, Issue 2 , July 2016, , Pages 37-48
Abstract
Power plants and refineries due to their process and consumption of fossil fuels release carbon dioxide into the environment and, as a consequence, both industries are polluting. In this study, the link between energy consumption and carbon dioxide emissions at power plants and refineries is surveyed ...
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Power plants and refineries due to their process and consumption of fossil fuels release carbon dioxide into the environment and, as a consequence, both industries are polluting. In this study, the link between energy consumption and carbon dioxide emissions at power plants and refineries is surveyed as added value in the form of Environmental Kuznets Curve. Results indicate that the bell-shaped curve for environmental studies of power plants as well as refineries over the period 1997-8 to 2011-12 is established. Results have shown a U-shaped relationship for power plants and N-shaped interfaces for the refinery. This means that, during the economic growth in power plants, CO2 emissions are increasing and, in refineries, that process has first decreased and then increased. Also, as a part of this study, energy consumption had a positive significant correlation with CO2 emissions.
