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
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.