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Abstract The annual market demand for disposable baby diapers exceeds 20 billion units (690 kt) in the European Union (EU). Almost 40,000 disposable diapers are used every minute, producing 1.3 t/min (dry weight) of waste. Based on the estimates in this work, this requires 90.3 PJ of primary energy and emits 2.7 Mt CO 2 eq. annually. In an attempt to reduce resource, waste and environmental impacts associated with diapers, this paper focuses on novel design and manufacture of disposable baby diapers. This involves using optimised absorbent core and novel bonding technologies to replace conventional gluing of diaper materials. Life cycle assessment has been performed to compare the environmental performance of these new diapers, here termed "glueless", with standard designs. The annual resource consumption and environmental impacts of glueless diapers have been estimated at different production levels: a single production platform, an industrial plant, a country (Italy) and the EU, taking into account different production volumes, electricity mixes and waste management options. Different market penetration scenarios have been considered to determine potential environmental implications at the EU level by 2020. The results reveal that glueless diapers reduce the consumption of raw materials by 23% (9.2 g/diaper), primary energy demand by 25% (752 kJ/diaper) and global warming potential by 10% (10.4 g CO 2 eq./diaper) compared to the standard diapers. They also have more than 50% lower eutrophication, ozone depletion and human and eco-toxicity. Up to 16 PJ primary energy and 191,000 t CO 2 eq. would be saved annually in the EU by using glueless diapers. The cumulative savings would amount to 47 PJ and 566,000 t CO 2 eq. by 2020. The annual consumption of raw materials at the EU level would be reduced by 196,000 t with cumulative savings of up to 584,000 t by 2020, also reducing the equivalent amount of waste from the disposal of diapers. Consequently, glueless diapers can contribute to meeting the energy, climate and resource efficiency goals specified in the EU 2020 strategy. Graphical abstract Image 1 Highlights • Novel design and manufacture of "glueless" disposable baby diapers is considered. • Glueless diapers save 23% of materials and 25% of energy relative to standard type. • Most life cycle impacts are reduced by >50% and global warming potential by 10%. • Up to 584,000 t of waste and 566,000 t of CO 2 eq. can be saved by 2020. • Glueless diapers can help meet the EU energy, resource and climate change targets. [ABSTRACT FROM AUTHOR]

Abstract A rapid development of building environmental research from the globe is witnessed in recent years to deal with the environmental issues, especially in terms of energy consumption and carbon emissions, due to the substantial environmental burdens associated with the building industry. Thus, numerous scientific efforts have been devoted to buildings through environmental assessment like a life cycle assessment (LCA) and a methodological framework development. Concerning the rapid growth of buildings, LCA is increasingly used for assessing and mitigating the associated environmental impacts from material selection to the whole building systems. This study aims to comprehensively review the LCA implication on buildings by discussing the contemporary issues related to the development of this research field. The study considers a wide range of literature including case studies, reviews and surveys, and these articles are critically examined according to the predefined criteria developed. An in-depth analysis is also conducted on selected studies to unveil the criticality of the assessments and results under different considerations. In addition to demonstrating the research gaps for comprehensive assessment of buildings, the adoption of a circular economy (CE) concept is highlighted by providing a comprehensive framework. The findings show that resource recovery and resource-efficient building construction are seldom considered in prevailing studies. As a result, the framework proposed in this paper should help support a paradigm shift towards a comprehensive research for increasing the accuracy and practicability by introducing the CE principle to the building industry for enhancing its sustainability performance. Highlights • Literature related to building-environmental research was critically analyzed. • LCA implication on buildings was comprehensively reviewed by discussing the contemporary issues. • Selected papers were critically analyzed to unveil the research trends and practices. • Knowledge gaps for comprehensive assessment of buildings under the CE principle are identified. • Comprehensive framework based on the CE principle was proposed for comprehensiveness building LCA. [ABSTRACT FROM AUTHOR]

Laser cladding is one of the principal means of equipment remanufacturing and the environmental profiles of this technology has become a research focus. This paper examines the environmental impacts of cast iron cylinder head block remanufacturing through laser cladding using life cycle assessment (LCA), and compares it with the new cylinder head block manufacturing. Resource and energy consumptions of each manufacturing and remanufacturing processes are collected along the production line and then the results of six selected environmental impact categories are calculated. Consistency and sensitivity analysis is also conducted after life cycle impact assessment. The results reveal that cylinder head remanufacturing by laser cladding will achieve large environmental benefits, which can cut environment impact over the entire life cycle by 63.8% on average. This paper also discusses the trend of changes in environmental impacts using scenario analysis over different remanufacturing levels. By taking characterized global warming potential (GWP) as the assessment index, the result shows that remanufacturing will no longer be the preferred option if it needs to repair more than 16 cracks by laser cladding for the cylinder head. [ABSTRACT FROM AUTHOR]

Nowadays, several technologies and management strategies are proposed for upgrading wastewater treatment plants (WWTPs) in order to improve sludge stabilization or minimize sludge production. In order to make sure that this leads to overall improvements, their techno-economic and environmental performance has to be carefully evaluated. In response to this, the techno-economic and environmental performance was assessed for a considered model reference WWTP upgraded with separate treatment and disposal for primary and secondary sludge to provide guidance to research, policy and investment efforts. This paper departs in an experimental campaign carried out within the EU project “ROUTES” and describes an assessment of an upgrade of a WWTP, involving wet oxidation of primary sludge and thermophilic anaerobic digestion (integrated with thermal hydrolysis pre-treatment) for secondary sludge. The reference plant and the upgrade implied different disposal routes for the resulting sludges: incineration for the stabilized sludge deriving from the reference WWTP; agricultural land application for the secondary stabilized sludge from the upgraded plant and landfilling for the solid residue deriving from the wet oxidation process (as non-hazardous waste). The mass balance carried out for both reference and upgraded WWTPs showed a reduction of total sludge production (up to 45%) for the upgraded WWTP. The additional energy demand of the upgraded solution (+22.4 Wh/(PE d), PE: population equivalent) was partially balanced by the electric energy produced by combined heat and power unit installed in the upgraded WWTP (−18.08 Wh/(PE d)). The integrated assessment showed that the upgraded solution, although resulting in an increase of WWTP technical complexity, may contribute to environmental and economic advantages. The paper provides guidance in terms of which aspects need a more thorough evaluation when this upgrade is considered in real cases. [ABSTRACT FROM AUTHOR]

This paper explores the environmental impacts of drill and blast tunnelling by life cycle assessment. In order to understand the potential of cleaner tunnelling, this paper also analysis the influence of tunnel length and size on pollutant emissions. The excavation practices of rock tunnel in Norway over past 20 years are used to estimate material, equipment and energy consumption. The background data are drawn out from various databases in the Simapro software. The results indicate that: 1) the most important contributor to the climate change and terrestrial eco-toxicity impacts are the loading and hauling process. Its relative contribution also increases when the tunnel becomes bigger or longer. 2) The drilling and blasting process is the dominate contributor to the human toxicity, photochemical oxidant formation, particulate matter formation and terrestrial acidification impacts. The relative influence of this process, however, slightly decreases when tunnels become bigger or longer. 3) The three main sources for all impacts are explosives, diesel and electricity. Therefore, a significant potential of environmental impacts reduction could be reached by optimising drilling and blasting operation to reduce explosive consumption, and by improving renewable energy sharing. [ABSTRACT FROM AUTHOR]

The paper aims to analyse and compare the environmental performances of the most widely used cooking appliances (the induction hob vs. the gas hob) considering a typical Italian scenario in terms of food, family and social habits. Cooking appliances are subject to energy labelling, and they represent the most impacting system inside households. This study was performed in accordance with the international standard, ISO 14040/14044, by using an attributional Life Cycle Assessment (aLCA). The functional unit is defined as the “preparation of a complete homemade meal (lunch) for 20 years consumed by a four-member family in Italy”. This study shows the dominance, in terms of environmental impact, of the induction hob with respect to the gas hob for most of the selected midpoint indicators. In particular, the induction hob accounts for more than 60% of the climate change and ozone depletion impact categories and more than 70% of the metal depletion category. The same trend is also noticed in the end-point categories (human health, ecosystem qualities and resources) and for the Cumulative Energy Demand indicator. Based on the experimental evidence of this work, the use phase is the most important due to the different energy carriers (natural gas vs. electrical energy). This finding is the result of the nature of the energy carrier (the electricity grid mix) in the Italian scenario, which is mainly based on non-renewable sources. In addition, concerning the production phase of the two appliances, the induction hob shows a relevant dominance in terms of the human toxicity and metal depletion impact categories due to the use of rare metals and coppers in the cooktop part manufacturing. The outcomes obtained from this study may be used by household manufacturers to improve the performance and design solutions of their appliances as well as by end users in their selection of cooking technologies. [ABSTRACT FROM AUTHOR]

Eco-design that addresses the consumption of resources and energy, as well as pollution emissions from a product life-cycle perspective, is an effective way to solve environmental problems. However, the optimal eco-design solution is hardly generated in the conceptual design stage due to the complex association of the life cycle design information. To this end, this paper proposes a new eco-design model based on a life cycle integrated framework to effectively manage life cycle information in the conceptual design phase. In this work, (1) The life cycle-oriented model is proposed to integrate the product design information in terms of a systematic association mechanism between function, structure, material and process to construct the design space. (2) A life cycle design scenario-based similarity matching method is developed to support the environmental impact assessment of design options in the design space. (3) A hope tree-based heuristic search algorithm with the principle of minimizing environmental impact is proposed to efficiently obtain the eco-design solution. An application for eco-design of the lift equipment is given to demonstrate the capability of the proposed method. The results show that the environmental impact of the generated eco-design solution is improved by 19.48%, and the material and use stage has the highest environmental impact which accounts for 39.59% and 47.74% respectively. This work provides a targeted method for guiding designers to implement eco-design in the conceptual design phase through the life cycle. [Display omitted] • An integrated life cycle model is proposed to express the design information of function, structure, material and process. • A scenario-based similarity matching method is proposed to acquire the LCI for the design options. • Hope tree-based algorithm is used to efficiently obtain the optimal eco-design solution. [ABSTRACT FROM AUTHOR]

As economies in the European Union are ultimately driven by the final consumption of citizens, policy makers need proper indicators to monitor the environmental impacts associated with this consumption. These indicators can be constructed using two different approaches, each having their strengths and limitations. The top-down approach is based on environmentally extended input–output analysis and quantifies the environmental impacts of product groups and services provided by industrial sectors. The bottom-up approach is based on Life Cycle Assessment and quantifies the environmental impacts of a selection of representative products. The bottom-up approach has already been used by the European Commission's Joint Research Centre to calculate the impacts of the final consumption per capita in the European Union in 2006. In this paper, we calculated these impacts through a top-down approach, using the Exiobase database. The covered household activities are food, consumer goods, mobility, shelter and services. The goal was to calculate all the impact categories recommended by the International Reference Life Cycle Data handbook, and compare both approaches. However, the categories ionizing radiation, toxicity and abiotic resource depletion could not be included, as some relevant emissions and resources are not available in Exiobase. To study more profoundly the impact on natural resources, we added the Cumulative Exergy Extraction From the Natural Environment to the impact assessment. When comparing both approaches, it can be concluded that there is a considerable shift in the results. This means that the information obtained by a top-down approach could supplement the information base for policy support. [ABSTRACT FROM AUTHOR]

Evaluations of the environmental sustainability of lifestyles and consumption practices have been taking centre stage in European research projects in recent years. Considerable work has been undertaken on the environmental assessment of food consumption patterns, and several analytical tools and methodologies have been proposed to quantify the environmental burden of production and consumption. Claims have been made in several international reports that the Mediterranean diet offers the best consumption pattern in terms of both the environment and health, but there has never been a specific assessment of the Mediterranean diet in comparison with other food consumption behaviours. This paper explores the environmental burdens of the Mediterranean diet applied in the Italian context. The environmental performance of this diet is compared to the national average diet in Italy, as well as to two empirical scenarios of healthy and vegetarian food consumption patterns. The environmental burdens of the different diets are assessed in terms of their energy consumption and their carbon footprint using a hybrid IOA-LCA method. This method considers the positive aspects of both bottom-up methodologies (e.g. life cycle assessment – LCA) and top-down methodologies (e.g. input–output analysis – IOA). The results allow several comparisons to be made between the different diets. When compared with the national average diet, the Mediterranean diet reveals an improvement in environmental performance of 95.75 MJ (2.44%) and 27.46 kg CO 2 equivalent (6.81%) per family. The best overall environmental performance can be found with the vegetarian diet in which energy consumption is 3.14% lower and the carbon footprint 12.7% lower than the national average diet. [ABSTRACT FROM AUTHOR]

The reduction in the use of raw materials and the spread of energy efficient processes and components are necessary from both the economic and the environmental viewpoints. This paper presents the design of an innovative multi-functional agricultural machinery able to integrate three separate traditional implements used for hay raking, hay baling and bale wrapping, i.e. hay rake, round baler and bale wrapper machines, with the aim of speeding up the harvesting operations and reducing both the energy consumption and the global environmental impact. A comparative analysis about the adoption of the traditional implements and the new multi-functional machinery is reported. Particularly, the reduction in both the fuel consumption (−32%), the human labor (−66.7%) is discussed together with a differential environmental analysis of the proposed system and the traditional implements. To meet such a last purpose, the study adopts the life cycle assessment methodology carefully quantifying the impact indicators for three different categories, i.e. human health, ecosystem quality and resource depletion. The results highlight a global environmental impact reduction of about 35%. The proposed system represents an effective and competitive improvement to ease and speed the haymaking process and to reduce the environmental impact of such a key farmer activity. [ABSTRACT FROM AUTHOR]