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
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.
