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Straw pulp in China, which is the world's largest producer of this material, suffers from water and energy shortages during its entire life cycle. However, limited systematic studies have focused on these issues, and decision makers need be provided with improvement methods for the environmental performance. Thus, an impact-oriented energy and carbon coupled water footprint analysis was conducted in this study based on ISO standards. Results showed that the impact of energy consumption and carbon emissions exceeded that of water footprint. Carcinogens, non-carcinogens, and freshwater ecotoxicity also played effective roles in improving the environmental performance. Optimizing key indirect processes, including chemicals production, steam preparation, electricity generation, wood pulping, and fertilizer recovery, dominated the reduction in environmental burdens. Direct freshwater consumption and wastewater disposal played additional effective roles in controlling water footprint. The water network was thus optimized by a water pinch analysis to decrease the freshwater consumption and pollutant emissions by maximum values of 91.5% and 99.7% after optimization, respectively. Meanwhile, carbon dioxide, methane, chromium, arsenic, mercury, titanium, copper, strontium, total nitrogen, total phosphorus, BOD 5 , and COD were the main pollutants. Overall, the environmental impact can be further reduced by diminishing coal power ratio in national energy structure, adopting recovered steam, and considering multistage regeneration water network to cope with different water use demands. • LCA-based energy and carbon coupled water footprint of straw pulp paper was applied. • Optimizing water network by water pinch method gained marked environmental benefit. • Electricity, steam, and chemicals exerted high impact among all inputs considered. • CO 2 , CH 4 , heavy metals, coal, and water were key contributors to footprint impact. • Improving national energy structure and adopting recovered steam were recommended. [ABSTRACT FROM AUTHOR]

Abstract: Life cycle assessment was carried out using IMPACT2002+ to estimate the environmental impact of coated white board production, which is common in China. Normalized results showed that the potential impacts of respiratory inorganics, terrestrial ecotoxicity, global warming, and non-renewable energy had a dominant contributions to overall environmental impact. Specifically, emissions from chemical and energy production processes exhibited higher potential impact (more than 80% of the total contribution) on the environment than that of emissions generated from transport, landfill, wastewater treatment, and paper plants infrastructure. Energy recovery from black liquor and energy generation based on natural gas are key factors in reducing overall environmental potential impact. The current paper presents improvements on the environmental performance of a coated white board production site in China. [Copyright &y& Elsevier]

This paper compares the energy and environmental impacts of organic and conventional apples cultivated in the North of Italy, by applying the Life Cycle Assessment (LCA) methodology. The authors examined the supply chain of apples, including the input of raw materials and energy sources, the farming step, the post-harvest processes and the distribution of apples to the final users. The paper develops two original contributions: 1) it enhances the limited number of studies on LCA applied to apples; 2) it compares organic and conventional apples produced in lands characterized by the same climatic conditions, to evaluate which of the two products is more competitive from an energy and environmental point of view. The results showed that, despite a lower productivity, preferring organic apples versus conventional apples could help to reduce the environmental impacts for most of the examined impact categories. With a few exceptions, differences lower than 7% occur between the eco-profiles of the two examined products. A relevant share of the primary energy consumption and almost all of the examined environmental impacts are caused by the post-harvest processes and by transport to the final users, assuming that the products are distributed on local, national and international markets. Furthermore, a detailed analysis of the farming step showed that a significant share in the overall energy and environmental impacts is due to the use of fertilizers and pesticides and to diesel consumption of agricultural machines. [ABSTRACT FROM AUTHOR]

In this study, the environmental impacts were assessed for five municipal solid waste (MSW) treatment processes with energy recovery potential. The life cycle assessment (LCA) tool was used to quantify the environmental impacts. The five processes considered are incineration, gasification, anaerobic digestion, bio-landfills, and composting. In addition, these processes were compared to recycling where applicable. In addition to environmental impacts quantification, the energy production potentials for the five processes were compared to provide a thorough assessment. To maximize the future applicability of our findings, the analyses were based on the waste treatment technologies as they apply to individual waste streams, but not for a specific MSW mixture at a particular location. Six MSW streams were considered; food, yard, plastic, paper, wood and textile wastes. From an energy recovery viewpoint, it was found that it is best to recycle paper, wood and plastics; to anaerobically digest food and yard wastes; and to incinerate textile waste. On the other hand, the level of environmental impact for each process depends on the considered impact category. Generally, anaerobic digestion and gasification were found to perform better environmentally than the other processes, while composting had the least environmental benefit. [ABSTRACT FROM AUTHOR]

The objective of this paper was to assess the environmental performance of the chicken meat chain, including 119 different farms, slaughterhouses, meat processors and retailers, as well as 500 households. A total of 619 life cycle assessment calculations have been completed to identify and quantify the environmental impacts from a cradle-to-grave perspective covering five subsystems: ‘chicken farm’, ‘slaughterhouse’, ‘meat processing plant’, ‘retail’ and ‘household use’. Structured surveys in selected entities have been conducted in order to collect life cycle inventory input data. Five environmental impact potentials were calculated in this study: global warming potential, acidification potential, eutrophication potential, ozone layer depletion and cumulative energy demand. The focus of the research was put on global warming potential, ozone layer depletion and cumulative energy demand, as these three indicators had significant values for each of the examined subsystems. As a general finding, this study found that the largest contributor to the environmental profile of the entire chicken meat chain is feed production and energy usage. Mitigation options for optimization of environmental impacts rely on the utilization of grain legumes as protein source in feed, treating of chicken litter in a biogas digester, application of the energy efficient equipment through the entire chain and recycling of household waste. [ABSTRACT FROM AUTHOR]

In support of continuous environmental improvement in the mining industry, it is important to systematically assess the environmental impacts of mining and mineral processing operations from a life cycle perspective. Although life cycle assessment (LCA) is widely used as an environmental systems analysis tool, the application of LCA in the mining industry is still in progress. This paper carried out a cradle-to-gate LCA of an underground copper ore mine planned in Northern Norway. Based on the ReCiPe midpoint (hierarchist) life cycle impact assessment method, results of the study showed that on-site electricity use, diesel for mining trucks and blasting dominated contributions across six, four and four, respectively, of the eighteen categories assessed, and metals leaching from tailings were the primary contributors to the human toxicity and marine ecotoxicity impacts. Compared to the baseline, results of the energy-oriented scenario analysis indicated that electrification of diesel-driven mining trucks would be more environmentally beneficial as long as the electrical supply is “relatively clean” across impact categories. While electrodialytic tailings remediation could extract up to 64% of copper in tailings prior to disposal and significantly reduce the human toxicity impact of tailings, the marine ecotoxicity impact of tailings after electrodialysis changed inconsistently across the ReCiPe hierarchist and egalitarian perspectives. It is recommended to further assess the trade-off between the benefits of electrodialytic tailings remediation (extracting more copper) and the potential impacts of deposited tailings after electrodialysis from a multi-criteria decision-analysis perspective. In a generic context, this study provides an insight in further promoting LCA as an environmental decision-support tool, especially for comparing available cleaner production options, improving the overall environmental performance of a mine, and facilitating better communication with stakeholders. [ABSTRACT FROM AUTHOR]

The aim of this study is to perform a life cycle and energy flow assessments of Municipal Solid Waste (MSW). These latter are modeled using Artificial Neural Network (ANN) for integrated waste management system in Tehran Municipality, Iran. The initial data used in this study have been obtained from Waste Management Organization of Tehran Municipality, while the required data related to the background system were extracted from the EcoInvent 2.2 database. Based on the obtained results from the energy cycle analysis, energy consumptions for transportation and processing plus recycling were calculated as 227.02 and 155.95 Gigajoules (GJ), respectively for 8500 t MSW. This energy consumption has led to the production of 18,884.03 GJ energy output (recycled materials) with an energy ratio of 121.56. A high energy ratio demonstrated that recycling of municipal solid is a new gateway against energy challenges. By optimizing energy consumption, especially energy related to transportation, this ratio could increase more than before. The results obtained from Life Cycle Assessment (LCA) indicate that transportation is considered the most important hot spot in the recycling of MSW while recycling papers is the main contributor to the redaction of environmental indicators in the recycling system. More intensity is observed for indicators related to toxicity due to the lack of waste disposal and to the entry of undesirable substances in natural resources. The 5-7-7-11 structure is the best topology to predict the amount of recycled materials and the impacts of environmental emissions from MSW recycling process developed by feed-forward back-propagation ANN models which are based on Levenberg-Marquardt (LM) training algorithm. Coefficient of determination values for train are in the ranges of 0.926–0.978 and have excellent performance in predicting all the output parameters based on the input parameters. [ABSTRACT FROM AUTHOR]

Efforts undertaken for reducing environmental impacts of energy production have been primarily focused on carbon reduction while the fact that energy production also requires water has been largely overlooked. During the last decade, and despite the fact that global warming still remains today the focus of many environmental evaluations, water scarcity issues have increasingly received attention. Despite the fact that recently, an increasing demand for large industrial companies to calculate and report on their water footprint exists, water resources have only recently been addressed in life cycle assessment (LCA) and their assessment still lacks wide application. The paper presents a practitioner's experience with respect to the application of three recently developed water footprinting methodologies that are considered as current-state-of-the-art. The methods are applied with as objective the estimation of the water footprint of combined cycle gas turbines with different cooling technologies. The study reveals that absolute values of water footprints (L eq. kWh −1 ) are very different among methods and therefore results are not directly comparable in terms of their absolute results. In contrast, ranking among power plants agree for the different methods when large differences in water consumption/impact exist. However, the ranking may differ between different methods when differences are small. It therefore remains impossible to select one method as the preferred method to use. This study therefore serves as support to the recently emerging working groups (eg. WULCA) that aim at harmonizing the different existing methodologies. [ABSTRACT FROM AUTHOR]

The shortage of resources and environmental pollution have become the social issues of world concern, they have seriously affected the sustainable development. Remanufacturing has been recognized as an effective technology helps to improve the energy and materials utilization, and reduce environmental emissions with a low cost. we performed a comprehensive literature review of assessing energy, environment, and economy in remanufacturing based on life cycle assessment method to summarize the development of remanufacturing technologies, conclude new progress of remanufacturing in energy, environment and economy and review the remanufacturing trend. Firstly, we reviewed the life cycle assessment (LCA) method and its application in remanufacturing assessment. Some remanufacturing assessment methods based on LCA were analyzed here. Secondly, a framework of assessing energy, environment, and economy in remanufacturing based on LCA was built. Corresponding assessment methods in remanufacturing were studied and summarized in dimensions of energy, environment and economy respectively. Then following the integrated studies of energy-environment-economic assessment in remanufacturing was also described. In this paper, the remanufacturing and assessment about energy, environment, economy based on LCA were described systematically, so as to better understand and apply LCA and promote remanufacturing. Finally, the limitations of the LCA method were discussed, furthermore, in order to catch up with the trend of the manufacturing industry, the integration of remanufacturing and emerging technologies was proposed at the end of the paper, which will be conducive to the continuous innovation of remanufacturing. • Reviewing the life cycle assessment method and its application in remanufacturing assessment. • Illustrating energy, environment and economic assessment methods in remanufacturing. • Performing integrated studies of energy-environment-economic assessment in remanufacturing. • Discussing the emerging technologies or methods of remanufacturing from the energy, environment and economic perspectives. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes a pavement life cycle assessment (LCA) model developed to evaluate energy use and greenhouse gas (GHG) emissions from pavement rehabilitation strategies. The LCA model analyzes the energy and GHG emissions associated with material production, construction and pavement use, which includes the effects of pavement rolling resistance on vehicle operation. The model was used to evaluate a set of case studies of pavement rehabilitation for both asphalt and concrete surfaces with different rolling resistances and traffic levels. The primary goal of the case studies is to evaluate the effect of rolling resistance on the life cycle performance of pavements, not to compare asphalt and concrete pavements. Energy and GHG emission savings from pavement rehabilitation are compared with an alternative where no rehabilitation occurs, only routine maintenance of damaged pavement. The results of the case studies show that for highway sections with high traffic volumes the energy and GHG savings accrued during the use phase due to reduced rolling resistance can be significantly larger than the energy use and GHG emissions from material production and construction, with the extent of the benefit dependent on constructed smoothness. These savings can be larger than those from other strategies to reduce highway transportation energy use and emissions, such as projected improvements in vehicle fuel economy. For low traffic volume highways, the smoothness obtained by the contractor and materials used have a more significant effect on the performance of the rehabilitation, and may result in a net increase in energy use and GHG emissions if low traffic volumes and poor construction quality occur together. [Copyright &y& Elsevier]