A Comparative Life Cycle Assessment on Nuclear-Based Clean Ammonia Synthesis Methods

2020 ◽  
Vol 142 (10) ◽  
Author(s):  
Ali Erdogan Karaca ◽  
Ibrahim Dincer ◽  
Junjie Gu

Abstract This paper evaluates the impacts of nuclear ammonia synthesis options on the environment through the life cycle assessment (LCA) technique. Ammonia is synthesized via the mature Haber–Bosch technique that combines hydrogen and nitrogen with 3:1 ratio to yield ammonia. For hydrogen production from water, five different hydrogen production methods are used, namely, conventional electrolysis (CE), high-temperature electrolysis (HTE), and 3-, 4-, and 5-step Cu–Cl cycles. The nitrogen required for ammonia synthesis is extracted from the air by the cryogenic air separation technique. The thermal and electrical energy need of production processes is supplied from a pressurized water reactor type nuclear power plant (NPP). The simapro software is utilized for LCA in the present study. The environmental impacts of nuclear ammonia are investigated through five impact categories, namely, abiotic depletion potential, acidification potential, global warming potential (GWP), ozone depletion potential, and human toxicity potential. According to LCA results, ammonia synthesis via HTE corresponds to the lowest environmental impact in all selected impact categories. Furthermore, the GWP for ammonia production via HTE is 0.1832 kg CO2 eq/kg ammonia, followed by CE (0.2240 kg CO2 eq/kg ammonia), 4-step Cu–Cl (0.3113 kg CO2 eq/kg ammonia), 3-step Cu–Cl (0.3323 kg CO2 eq/kg ammonia), and 5-step Cu–Cl (0.3370 kg CO2 eq/kg ammonia).

Fibers ◽  
2019 ◽  
Vol 7 (7) ◽  
pp. 59 ◽  
Author(s):  
Catarina Brazão Farinha ◽  
José Dinis Silvestre ◽  
Jorge de Brito ◽  
Maria do Rosário Veiga

The production of waste is increasing yearly and, without a viable recycle or reutilization solution, waste is sent to landfills, where it can take thousand to years to degrade. Simultaneously, for the production of new materials, some industries continue to ignore the potential of wastes and keep on using natural resources for production. The incorporation of waste materials in mortars is a possible solution to avoid landfilling, through their recycling or reutilization. However, no evaluation of their “sustainability” in terms of environmental performance is available in the literature. In this sense, in this research a life cycle assessment was performed on mortars, namely renders, with incorporation of industrials wastes replacing sand and/or cement. For that purpose, eight environmental impact categories (abiotic depletion potential, global warming potential, ozone depletion potential, photochemical ozone creation potential, acidification potential, eutrophication potential, use of non-renewable primary energy resources, and use of renewable primary energy resources) within a “cradle to gate” boundary were analyzed for 19 mortars with incorporation of several industrial wastes: sanitary ware, glass fiber reinforced polymer, forest biomass ashes, and textile fibers. Sixteen out of the 19 mortars under analysis presented, in all environmental impact categories, an equal or better environment performance than a common mortar (used as a reference). The benefits in some environmental impacts were over 20%.


Author(s):  
Elias Marvinney ◽  
Alissa Kendall

Abstract Purpose California’s Central Valley produces more than 75% of global commercial almond supply, making the life cycle performance of almond production in California of global interest. This article describes the life cycle assessment of California almond production using a Scalable, Process-based, Agronomically Responsive Cropping System Life Cycle Assessment (SPARCS-LCA) model that includes crop responses to orchard management and modeling of California’s water supply and biomass energy infrastructure. Methods A spatially and temporally resolved LCA model was developed to reflect the regional climate, resource, and agronomic conditions across California’s Central Valley by hydrologic subregion (San Joaquin Valley, Sacramento Valley, and Tulare Lake regions). The model couples a LCA framework with region-specific data, including water supply infrastructure and economics, crop productivity response models, and dynamic co-product markets, to characterize the environmental performance of California almonds. Previous LCAs of California almond found that irrigation and management of co-products were most influential in determining life cycle CO2eq emissions and energy intensity of California almond production, and both have experienced extensive changes since previous studies due to drought and changing regulatory conditions, making them a focus of sensitivity and scenario analysis. Results and discussion Results using economic allocation show that 1 kg of hulled, brown-skin almond kernel at post-harvest facility gate causes 1.92 kg CO2eq (GWP100), 50.9 MJ energy use, and 4820 L freshwater use, with regional ranges of 2.0–2.69 kg CO2eq, 42.7–59.4 MJ, and 4540–5150 L, respectively. With a substitution approach for co-product allocation, 1 kg almond kernel results in 1.23 kg CO2eq, 18.05 MJ energy use, and 4804 L freshwater use, with regional ranges of 0.51–1.95 kg CO2eq, 3.68–36.5 MJ, and 4521–5140 L, respectively. Almond freshwater use is comparable with other nut crops in California and globally. Results showed significant variability across subregions. While the San Joaquin Valley performed best in most impact categories, the Tulare Lake region produced the lowest eutrophication impacts. Conclusion While CO2eq and energy intensity of almond production increased over previous estimates, so too did credits to the system for displacement of dairy feed. These changes result from a more comprehensive model scope and improved assumptions, as well as drought-related increases in groundwater depth and associated energy demand, and decreased utilization of biomass residues for energy recovery due to closure of bioenergy plants in California. The variation among different impact categories between subregions and over time highlight the need for spatially and temporally resolved agricultural LCA.


Author(s):  
V. Russo ◽  
A. E. Strever ◽  
H. J. Ponstein

Abstract Purpose Following the urgency to curb environmental impacts across all sectors globally, this is the first life cycle assessment of different wine grape farming practices suitable for commercial conventional production in South Africa, aiming at better understanding the potentials to reduce adverse effects on the environment and on human health. Methods An attributional life cycle assessment was conducted on eight different scenarios that reduce the inputs of herbicides and insecticides compared against a business as usual (BAU) scenario. We assess several impact categories based on ReCiPe, namely global warming potential, terrestrial acidification, freshwater eutrophication, terrestrial toxicity, freshwater toxicity, marine toxicity, human carcinogenic toxicity and human non-carcinogenic toxicity, human health and ecosystems. A water footprint assessment based on the AWARE method accounts for potential impacts within the watershed. Results and discussion Results show that in our impact assessment, more sustainable farming practices do not always outperform the BAU scenario, which relies on synthetic fertiliser and agrochemicals. As a main trend, most of the impact categories were dominated by energy requirements of wine grape production in an irrigated vineyard, namely the usage of electricity for irrigation pumps and diesel for agricultural machinery. The most favourable scenario across the impact categories provided a low diesel usage, strongly reduced herbicides and the absence of insecticides as it applied cover crops and an integrated pest management. Pesticides and heavy metals contained in agrochemicals are the main contributors to emissions to soil that affected the toxicity categories and impose a risk on human health, which is particularly relevant for the manual labour-intensive South African wine sector. However, we suggest that impacts of agrochemicals on human health and the environment are undervalued in the assessment. The 70% reduction of toxic agrochemicals such as Glyphosate and Paraquat and the 100% reduction of Chlorpyriphos in vineyards hardly affected the model results for human and ecotoxicity. Our concerns are magnified by the fact that manual labour plays a substantial role in South African vineyards, increasing the exposure of humans to these toxic chemicals at their workplace. Conclusions A more sustainable wine grape production is possible when shifting to integrated grape production practices that reduce the inputs of agrochemicals. Further, improved water and related electricity management through drip irrigation, deficit irrigation and photovoltaic-powered irrigation is recommendable, relieving stress on local water bodies, enhancing drought-preparedness planning and curbing CO2 emissions embodied in products.


2021 ◽  
Vol 13 (6) ◽  
pp. 3436
Author(s):  
Hani A. Abu-Qdais ◽  
Muna A. Abu-Dalo ◽  
Yazan Y. Hajeer

Due to their properties, silver nanoparticles (AgNPs) are widely used in consumer products. The widespread use of these products leads to the release of such nanoparticles into the environment, during manufacturing, use, and disposal stages. Currently there is a high margin of uncertainty about the impacts of nano products on the environment and human health. Therefore, different approaches including life cycle assessment (LCA) are being used to evaluate the environmental and health impacts of these products. In this paper, a comparison between four different AgNP synthesis methods was conducted. In addition, four textile products that contain AgNPs were subjected to comparison using LCA analysis to assess their environmental and public health impacts using SimaPro modeling platform. Study results indicate that using alternative methods (green) to AgNPs synthesis will not necessarily reduce the environmental impacts of the synthesizing process. To the best of our knowledge, this is the first study that has compared and assessed the environmental burdens associated with different nanosilver-based textile products at different disposal scenarios. The synthesis of 1 kg of AgNPs using modified Tollens’ method resulted in 580 kg CO2 eq, while 531 kg CO2 eq resulted from the chemical approach. Furthermore, the manufacturing stage had the highest overall impacts as compared to other processes during the life cycle of the product, while the product utilization and disposal stages had the highest impacts on ecotoxicity. Sensitivity analysis revealed that under the two disposal scenarios of incineration and landfilling, the impacts were sensitive to the amount of AgNPs.


2021 ◽  
Vol 13 (5) ◽  
pp. 2898
Author(s):  
Rakhyun Kim ◽  
Myung-Kwan Lim ◽  
Seungjun Roh ◽  
Won-Jun Park

This study analyzed the characteristics of the environmental impacts of apartment buildings, a typical housing type in South Korea, as part of a research project supporting the streamlined life cycle assessment (S-LCA) of buildings within the G-SEED (Green Standard for Energy and Environmental Design) framework. Three recently built apartment building complexes were chosen as study objects for the quantitative evaluation of the buildings in terms of their embodied environmental impacts (global warming potential, acidification potential, eutrophication potential, ozone layer depletion potential, photochemical oxidant creation potential, and abiotic depletion potential), using the LCA approach. Additionally, we analyzed the emission trends according to the cut-off criteria of the six environmental impact categories by performing an S-LCA with cut-off criteria 90–99% of the cumulative weight percentile. Consequently, we were able to present the cut-off criterion best suited for S-LCA and analyze the effect of the cut-off criteria on the environmental impact analysis results. A comprehensive environmental impact analysis of the characteristics of the six environmental impact categories revealed that the error rate was below 5% when the cut-off criterion of 97.5% of the cumulative weight percentile was applied, thus verifying its validity as the optimal cut-off criterion for S-LCA.


2016 ◽  
Vol 24 ◽  
pp. 531-537 ◽  
Author(s):  
C.P. Sunil Kumar ◽  
S. Parvathi ◽  
R. Rudramoorthy

Author(s):  
Yueling Zhang ◽  
Huan Liu ◽  
Junjie Li ◽  
Yelin Deng ◽  
Xiaopeng Miao ◽  
...  

2021 ◽  
Author(s):  
Dyah Ika Rinawati ◽  
Alexander Ryota Keeley ◽  
Shutaro Takeda ◽  
Shunsuke Managi

Abstract This study conducted a systematic literature review of the technical aspects and methodological choices in life cycle assessment (LCA) studies of using hydrogen for road transport. More than 70 scientific papers published during 2000–2021 were reviewed, in which more than 350 case studies of use of hydrogen in the automotive sector were found. Only some studies used hybrid LCA and energetic input-output LCA, whereas most studies addressed attributional process-based LCA. A categorization based on the life cycle scope distinguished case studies that addressed the well-to-tank (WTT), well-to-wheel (WTW), and complete life cycle approaches. Furthermore, based on the hydrogen production process, these case studies were classified into four categories: thermochemical, electrochemical, thermal-electrochemical, and biochemical. Moreover, based on the hydrogen production site, the case studies were classified as centralized, on-site, and on-board. The fuel cell vehicle passenger car was the most commonly used vehicle. The functional unit for the WTT studies was mostly mass or energy, and vehicle distance for the WTW and complete life cycle studies. Global warming potential (GWP) and energy consumption were the most influential categories. Apart from the GREET (Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation) model and the Intergovernmental Panel on Climate Change for assessing the GWP, the Centrum voor Milieukunde Leiden method was most widely used in other impact categories. Most of the articles under review were comparative LCA studies on different hydrogen pathways and powertrains. The findings provide baseline data not only for large-scale applications, but also for improving the efficiency of hydrogen use in road transport.


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