Life cycle assessment of a packaging waste recycling system in Portugal

Life Cycle Assessment (LCA) has been used to assess the environmental impacts associated with an activity or product life cycle. It has also been applied to assess the environmental performance related to waste management activities. This study analyses the packaging waste management system of a local public authority in Portugal. The operations of selective and refuse collection, sorting, recycling, landfilling and incineration of packaging waste were considered. The packaging waste management system in operation in 2010, which we called “Baseline” scenario, was compared with two hypothetical scenarios where all the packaging waste that was selectively collected in 2010 would undergo the refuse collection system and would be sent directly to incineration (called “Incineration” scenario) or to landfill (“Landfill” scenario). Overall, the results show that the “Baseline” scenario is more environmentally sound than the hypothetical scenarios.     

Influence of construction and demolition waste management on the environmental impact of buildings

The purpose of this study is to quantify comparable environmental impacts within a Life Cycle Analysis (LCA) perspective, for buildings in which the first (Materials) and last (End of Life) life cycle stages are adjusted to several waste/material management options. Unlike most LCAs, the approach is “top-down” rather than “bottom-up”, which usually involves large amounts of data and the use of specific software applications. This approach is considered appropriate for a limited but expedient LCA designed to compare the environmental impacts of different life cycle options.Present results, based on real buildings measurements and demolition contractor activities, show that shallow, superficial, selective demolition may not result in reduced environmental impacts. Calculations actually show an increase (generally less than 5%) in most impact categories for the Materials and End of Life stages because of extra transportation needs. However, core material separation in demolition operations and its recycling and/or reuse does bring environmental benefits. A reduction of around 77% has been estimated in the climate change impact category, 57% in acidification potential and 81% in the summer smog impact (for the life cycle stages referred).     

Models for waste life cycle assessment: Review of technical assumptions

A number of waste life cycle assessment (LCA) models have been gradually developed since the early 1990s, in a number of countries, usually independently from each other. Large discrepancies in results have been observed among different waste LCA models, although it has also been shown that results from different LCA studies can be consistent. This paper is an attempt to identify, review and analyse methodologies and technical assumptions used in various parts of selected waste LCA models. Several criteria were identified, which could have significant impacts on the results, such as the functional unit, system boundaries, waste composition and energy modelling. The modelling assumptions of waste management processes, ranging from collection, transportation, intermediate facilities, recycling, thermal treatment, biological treatment, and landfilling, are obviously critical when comparing waste LCA models.This review infers that some of the differences in waste LCA models are inherent to the time they were developed. It is expected that models developed later, benefit from past modelling assumptions and knowledge and issues. Models developed in different countries furthermore rely on geographic specificities that have an impact on the results of waste LCA models. The review concludes that more effort should be employed to harmonise and validate non-geographic assumptions to strengthen waste LCA modelling.     

Eco-efficient waste glass recycling: Integrated waste management and green product development through LCA

As part of the EU Life + NOVEDI project, a new eco-efficient recycling route has been implemented to maximise resources and energy recovery from post-consumer waste glass, through integrated waste management and industrial production. Life cycle assessment (LCA) has been used to identify engineering solutions to sustainability during the development of green building products. The new process and the related LCA are framed within a meaningful case of industrial symbiosis, where multiple waste streams are utilised in a multi-output industrial process. The input is a mix of rejected waste glass from conventional container glass recycling and waste special glass such as monitor glass, bulbs and glass fibres. The green building product is a recycled foam glass (RFG) to be used in high efficiency thermally insulating and lightweight concrete. The environmental gains have been contrasted against induced impacts and improvements have been proposed. Recovered co-products, such as glass fragments/powders, plastics and metals, correspond to environmental gains that are higher than those related to landfill avoidance, whereas the latter is cancelled due to increased transportation distances. In accordance to an eco-efficiency principle, it has been highlighted that recourse to highly energy intensive recycling should be limited to waste that cannot be closed-loop recycled.     

Waste management models and their application to sustainable waste management

The purpose of this paper is to review the types of models that are currently being used in the area of municipal waste management and to highlight some major shortcomings of these models. Most of the municipal waste models identified in the literature are decision support models and for the purposes of this research, are divided into three categories-those based on cost benefit analysis, those based on life cycle assessment and those based on multicriteria decision making. Shortcomings of current waste management models include that they are concerned with refinements of the evaluation steps (e.g. stage four of AHP or the improvement of weight allocations in ELECTRE) rather than addressing the decision making process itself. In addition, while many models recognise that for a waste management model to be sustainable, it must consider environmental, economic and social aspects, no model examined considered all three aspects together in the application of the model.     

Participatory approach, acceptability and transparency of waste management LCAs: case studies of Torino and Cuneo

The paper summarises the main results obtained from two extensive applications of Life Cycle Assessment (LCA) to the integrated municipal solid waste management systems of Torino and Cuneo Districts in northern Italy. Scenarios with substantial differences in terms of amount of waste, percentage of separate collection and options for the disposal of residual waste are used to discuss the credibility and acceptability of the LCA results, which are adversely affected by the large influence of methodological assumptions and the local socio-economic constraints. The use of site-specific data on full scale waste treatment facilities and the adoption of a participatory approach for the definition of the most sensible LCA assumptions are used to assist local public administrators and stakeholders showing them that LCA can be operational to waste management at local scale.     

Improvement actions in waste management systems at the provincial scale based on a life cycle assessment evaluation

This paper reports some of the findings of the ‘GERLA’ project: GEstione Rifiuti in Lombardia – Analisi del ciclo di vita (Waste management in Lombardia – Life cycle assessment). The project was devoted to support Lombardia Region in the drafting of the new waste management plan by applying a life cycle thinking perspective. The present paper mainly focuses on four Provinces in the Region, which were selected based on their peculiarities. Life cycle assessment (LCA) was adopted as the methodology to assess the current performance of the integrated waste management systems, to discuss strengths and weaknesses of each of them and to design their perspective evolution as of year 2020.Results show that despite a usual business approach that is beneficial to all the provinces, the introduction of technological and management improvements to the system provides in general additional energy and environmental benefits for all four provinces. The same improvements can be easily extended to the whole Region, leading to increased environmental benefits from the waste management sector, in line with the targets set by the European Union for 2020.     

The life cycle assessment of an e-waste treatment enterprise in China

Electrical and electronic waste (e-waste) has become one of the fastest growing waste streams in the world, and many countries have established e-waste treatment enterprises to solve their e-waste problems. In this study, a life cycle assessment (LCA) was undertaken to quantitatively investigate the environmental impacts of an e-waste treatment enterprise in China. The LCA is constructed by SimaPro software version 7.2 and expressed with the Eco-indicator 99 life cycle impact assessment method. For a sensitivity analysis of the overall LCA results, the so-called CML method is used in order to estimate the influence of the choice of the assessment method on the result. According to the survey data, discarded TV sets accounted for the highest proportion of e-waste treated in the enterprise in 2010. The e-waste treatment had little environmental impact, and at the same time large environmental benefits can be achieved mainly due to the recycled resources and reuse of some components. Based on the research results, it can be seen that recycled metal, especially copper, would be of more importance for environmental benefits. Relevant results and data from this study could provide decision support to enterprise managers and government sectors.     

Life cycle assessment of solid waste management options for Eskisehir, Turkey

Life cycle assessment (LCA) methodology was used to determine the optimum municipal solid waste (MSW) management strategy for Eskisehir city. Eskisehir is one of the developing cities of Turkey where a total of approximately 750tons/day of waste is generated. An effective MSW management system is needed in this city since the generated MSW is dumped in an unregulated dumping site that has no liner, no biogas capture, etc. Therefore, five different scenarios were developed as alternatives to the current waste management system. Collection and transportation of waste, a material recovery facility (MRF), recycling, composting, incineration and landfilling processes were considered in these scenarios. SimaPro7 libraries were used to obtain background data for the life cycle inventory. One ton of municipal solid waste of Eskisehir was selected as the functional unit. The alternative scenarios were compared through the CML 2000 method and these comparisons were carried out from the abiotic depletion, global warming, human toxicity, acidification, eutrophication and photochemical ozone depletion points of view. According to the comparisons and sensitivity analysis, composting scenario, S3, is the more environmentally preferable alternative. In this study waste management alternatives were investigated only on an environmental point of view. For that reason, it might be supported with other decision-making tools that consider the economic and social effects of solid waste management.     

Comparative environmental assessment of natural and recycled aggregate concrete

Constant and rapid increase in construction and demolition (C&D) waste generation and consumption of natural aggregate for concrete production became one of the biggest environmental problems in the construction industry. Recycling of C&D waste represents one way to convert a waste product into a resource but the environment benefits through energy consumption, emissions and fallouts reductions are not certain. The main purpose of this study is to determine the potentials of recycled aggregate concrete (concrete made with recycled concrete aggregate) for structural applications and to compare the environmental impact of the production of two types of ready-mixed concrete: natural aggregate concrete (NAC) made entirely with river aggregate and recycled aggregate concrete (RAC) made with natural fine and recycled coarse aggregate. Based on the analysis of up-to-date experimental evidence, including own tests results, it is concluded that utilization of RAC for low-to-middle strength structural concrete and non-aggressive exposure conditions is technically feasible. The Life Cycle Assessment (LCA) is performed for raw material extraction and material production part of the concrete life cycle including transport. Assessment is based on local LCI data and on typical conditions in Serbia. Results of this specific case study show that impacts of aggregate and cement production phases are slightly larger for RAC than for NAC but the total environmental impacts depend on the natural and recycled aggregates transport distances and on transport types. Limit natural aggregate transport distances above which the environmental impacts of RAC can be equal or even lower than the impacts of NAC are calculated for the specific case study.     

Environmental performance of construction waste: Comparing three scenarios from a case study in Catalonia,Spain

The main objective of this paper is to evaluate environmental impacts of construction wastes in terms of the LIFE 98 ENV/E/351 project. Construction wastes are classified in accordance with the Life Program Environment Directive of the European Commission. Three different scenarios to current waste management from a case study in Catalonia (Spain) have been compared: landfilling, recycling and incineration, and these scenarios were evaluated by means of Life Cycle Assessment. The recommendations of the Catalan Waste Catalogue and the European Waste Catalogue have been taken into account. Also, the influence of transport has been evaluated.Results show that in terms of the Global Warming Potential, the most environmentally friendly treatment was recycling, followed by incineration and lastly landfilling. According to the influence of treatment plants location on the GWP indicator, we observe that incineration and recycling of construction wastes are better than landfilling, even for long distances from the building site to the plants. This is true for most wastes except for the stony types, than should be recycled close to the building site.In summary, data from construction waste of a Catalan case study was evaluated using the well established method of LCA to determine the environmental impacts.     

Review of LCA studies of solid waste management systems – Part II: Methodological guidance for a better practice

Life cycle assessment (LCA) is increasingly used in waste management to identify strategies that prevent or minimise negative impacts on ecosystems, human health or natural resources. However, the quality of the provided support to decision- and policy-makers is strongly dependent on a proper conduct of the LCA. How has LCA been applied until now? Are there any inconsistencies in the past practice? To answer these questions, we draw on a critical review of 222 published LCA studies of solid waste management systems. We analyse the past practice against the ISO standard requirements and the ILCD Handbook guidelines for each major step within the goal definition, scope definition, inventory analysis, impact assessment, and interpretation phases of the methodology. Results show that malpractices exist in several aspects of the LCA with large differences across studies. Examples are a frequent neglect of the goal definition, a frequent lack of transparency and precision in the definition of the scope of the study, e.g. an unclear delimitation of the system boundaries, a truncated impact coverage, difficulties in capturing influential local specificities such as representative waste compositions into the inventory, and a frequent lack of essential sensitivity and uncertainty analyses. Many of these aspects are important for the reliability of the results. For each of them, we therefore provide detailed recommendations to practitioners of waste management LCAs.     

Possibilities and limitations of life cycle assessment (LCA) in the development of waste utilization systems – Applied examples for a region in Northern Germany

Against the background of increasing concerns about climate change, the reduction of greenhouse gas emissions has become an integral part of processes in both the waste management and the energy industries. This is reflected in the development of new waste treatment concepts, in which domestic and commercial waste is treated with the aim of utilizing its energy content, while at the same time recycling as much of its material content as possible. Life cycle assessment (LCA) represents a method of assessing the environmental relevance of a waste management system, the basis of which is a material flow analysis of the system in question. GHG emissions from different options for thermal treatment and energy recovery from waste as applied to a region in Northern Germany have been analyzed by the LCA approach and an indicative LCA, which only considers those emissions resulting from operating stages of the system. Operating stages have the main share of emissions compared to pre-processing stages. Results show that through specific separation of waste material flows and highly efficient energy recovery, thermal treatment and energy generation from waste can be optimized resulting in reduction of emissions of greenhouse gases. There are also other areas of waste utilization, currently given little attention, such as the solar drying of sewage sludge, which can considerably contribute to the reduction of greenhouse gas emissions.     

The role played by environmental factors in the integration of a transfer station in a municipal solid waste management system

Transfer stations are an integral part of present-day municipal solid waste management systems. The main criteria used to decide on the location of a transfer station has traditionally been the minimization of transport costs, since it is cheaper to transport great amounts of waste over long distances in large loads than in small ones. In this study, we are going to consider the environmental factor in order to compare the feasibility of using a transfer station integrated within a waste management system. Applying the Life Cycle Assessment technique will enable us to obtain an objective parameter that quantifies the environmental impact of transportation and of operating a transfer station. Taking the current rates of solid wastes generation in the Plana region of Castellón (Spain) as our starting point, in this study we compare the environmental costs involved in the process of taking municipal wastes directly to the nearest waste treatment facility, with those involved in a waste management system integrating a transfer station. Comparing these two cases, an average reduction of 16.8% in the environmental impact can be obtained when a transfer station is incorporated in the waste management system.     

LCA of integrated MSW management systems: case study of the Bologna District

LCA as a decision-supporting tool in planning integrated municipal solid waste management is not, as yet, widely used in Italy. This paper presents a study concerning the application of the LCA methodology to support the development of the new waste management plan for the Bologna District. The main goal of the study was to show decision-makers at the political level the benefits obtainable with the use of LCA, in terms of the identification and quantification of the potential environmental impacts of different waste management strategies. The integrated waste management system of the Bologna District includes waste collection and transport, sorting, recycling, composting, incineration and landfilling. Three scenarios, referring to 2006 and assuming the presence of 950,000 inhabitants and the production of approximately 566,000 t of waste in the district, have been compared. A detailed model has been developed in order to capture effects related to the waste fraction from separated collection and to the different waste treatments. The discussion of the results has focussed in particular on the greenhouse effect and the acidification potential. On the basis of the results obtained, the analysis of an additional scenario characterised by a further increase in separated collection has been put forward.     

What life-cycle assessment does and does not do in assessments of waste management

In assessments of the environmental impacts of waste management, life-cycle assessment (LCA) helps expanding the perspective beyond the waste management system. This is important, since the indirect environmental impacts caused by surrounding systems, such as energy and material production, often override the direct impacts of the waste management system itself. However, the applicability of LCA for waste management planning and policy-making is restricted by certain limitations, some of which are characteristics inherent to LCA methodology as such, and some of which are relevant specifically in the context of waste management. Several of them are relevant also for other types of systems analysis. We have identified and discussed such characteristics with regard to how they may restrict the applicability of LCA in the context of waste management. Efforts to improve LCA with regard to these aspects are also described. We also identify what other tools are available for investigating issues that cannot be adequately dealt with by traditional LCA models, and discuss whether LCA methodology should be expanded rather than complemented by other tools to increase its scope and applicability.     

Decision support models for solid waste management: Review and game-theoretic approaches

This paper surveys decision support models that are commonly used in the solid waste management area. Most models are mainly developed within three decision support frameworks, which are the life-cycle assessment, the cost–benefit analysis and the multi-criteria decision-making. These frameworks are reviewed and their strengths and weaknesses as well as their critical issues are analyzed, while their possible combinations and extensions are also discussed. Furthermore, the paper presents how cooperative and non-cooperative game-theoretic approaches can be used for the purpose of modeling and analyzing decision-making in situations with multiple stakeholders. Specifically, since a waste management model is sustainable when considering not only environmental and economic but also social aspects, the waste management bargaining game is introduced as a specific decision support framework in which future models can be developed.     

Spatial simulation and LCA evaluation on the plastic waste recycling system in Tianjin

With the rapid economic development in China, the amount of plastic waste (PW) generated has greatly increased and much of the waste is currently not treated. To reduce greenhouse gas (GHG) emissions from recycling of PW, we estimated the PW flow and considered methods to improve the household PW recycling system in Tianjin by adjusting processes during transportation and establishing a PW recycling factory in Zi’ya Industrial Park. The goal of the study was to identify reasonable improvements for the recycling system and clarify the environmental load. Geographic information system (GIS) technology was used to simulate transport processes for comparing GHG emissions from the transport processes between the present case and an improved case. Life cycle assessment (LCA) was used to compare GHG emissions between a projected scenario and a baseline scenario. Estimated GHG emissions during transport processes in the improved case were reduced by about 12,197 t CO₂ eq per year compared to the present case, equivalent to about 65.9 % of the total emissions in the present case. GHG emissions in the projected scenario were about 101,738 t CO₂ eq less per year than the baseline scenario, equivalent to about 75.5 % of the total emissions in the baseline scenario.     

Application of spatial and non-spatial data analysis in determination of the factors that impact municipal solid waste generation rates in Turkey

In studies focusing on the factors that impact solid waste generation habits and rates, the potential spatial dependency in solid waste generation data is not considered in relating the waste generation rates to its determinants. In this study, spatial dependency is taken into account in determination of the significant socio-economic and climatic factors that may be of importance for the municipal solid waste (MSW) generation rates in different provinces of Turkey. Simultaneous spatial autoregression (SAR) and geographically weighted regression (GWR) models are used for the spatial data analyses. Similar to ordinary least squares regression (OLSR), regression coefficients are global in SAR model. In other words, the effect of a given independent variable on a dependent variable is valid for the whole country. Unlike OLSR or SAR, GWR reveals the local impact of a given factor (or independent variable) on the waste generation rates of different provinces. Results show that provinces within closer neighborhoods have similar MSW generation rates. On the other hand, this spatial autocorrelation is not very high for the exploratory variables considered in the study. OLSR and SAR models have similar regression coefficients. GWR is useful to indicate the local determinants of MSW generation rates. GWR model can be utilized to plan waste management activities at local scale including waste minimization, collection, treatment, and disposal. At global scale, the MSW generation rates in Turkey are significantly related to unemployment rate and asphalt-paved roads ratio. Yet, significances of these variables may diminish at local scale for some provinces. At local scale, different factors may be important in affecting MSW generation rates.     

Direct and indirect generation of waste in the Spanish paper industry

The paper industry has a relatively high degree of reliance on suppliers when compared to other industries. Exploring the role of the paper industry in terms of consumption of intermediate inputs from other industries may help to understand how the production of paper does not only generate waste by itself but also affects the amount of waste generated by other industries. The product Life Cycle Assessment (LCA) is a useful analytical tool to examine and assess environmental impacts over the entire life cycle of a product “from cradle to grave” but it is costly and time intensive. In contrast, Economic Input Output Life Cycle Assessment Models (IO-LCA) that combine LCA with Input–Output analysis (IO) are more accurate and less expensive, as they employ publicly available data. This paper represents one of the first Spanish studies aimed at estimating the waste generated in the production of paper by applying IO-LCA. One of the major benefits is the derivation of the contribution of direct and indirect suppliers to the paper industry. The results obtained show that there was no direct relationship between the impact on output and the impact on waste generation exerted by the paper industry. The major contributors to waste generation were the mining industry and the forestry industry.