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1.
Minghui Xie Qi Qiao Qihong Sun Linlin Zhang 《The International Journal of Life Cycle Assessment》2013,18(3):626-635
Purpose
Approximately 46,000 t/day of packaging waste was generated in China in 2010, of which, 2,500 t was composite packaging waste. Due to the lack of recycling technology and an imperfect recovery system, most of this waste is processed in sanitary landfills. An effective packaging waste management system is needed since this waste not only uses up valuable resources, but also increases environmental pollution. The purpose of this study is to estimate the environmental impact of the treatment scenarios in composite packaging waste which are commonly used in China, to determine the optimum composite packaging waste management strategy, and to design new separating and recycling technology for composite packaging, based on the life cycle assessment (LCA) results.Methods
To identify the best treatment for composite packaging waste, the LCA software SimaPro 7.1.6 was used to assist in the analysis of the environmental impacts, coupled with the impact assessment method Eco-Indicator 99. LCA for composite packaging waste management was carried out by estimating the environmental impacts of the four scenarios most often used in China: landfill, incineration, paper recycling, and separation of polyethylene and aluminum. One ton of post-consumption Tetra Pak waste was selected as the functional unit. The data on the mass, energy fluxes, and environmental emissions were obtained from literature and site investigations.Results and discussion
Landfill—scenario 1—was the worst waste management option. Paper recycling—scenario 3—was more environmentally friendly than incineration, scenario 2. Scenario 4, separating out polyethylene and aluminum, was established based on the LCA result, and inventory data were obtained from the demonstration project built by this research. In scenario 4, the demonstration project for the separation of polyethylene and aluminum was built based on the optimum conditions from single-factor and orthogonal experiments. Adding this flow process into the life cycle of composite packaging waste treatment decreased the environmental impacts significantly.Conclusions
The research results can provide useful scientific information for policymakers in China to make decisions regarding composite packaging waste. Incineration could reduce more environmental impacts in the respiratory inorganics category, and separation of polyethylene and aluminum, in the fossil fuel category. If energy saving is the primary governmental goal, the separation of polyethylene and aluminum would be the better choice, while incineration would be the better choice for emission reduction. 相似文献2.
Emanuele Brambilla Pisoni Roberto Raccanelli Giovanni Dotelli Donatella Botta Paco Melià 《The International Journal of Life Cycle Assessment》2009,14(3):248-256
Background, aim, and scope Many recent studies on waste management have described in detail the potential impacts of recycling and final treatment of
municipal waste. In public debates, the attention has also been focused on the choice of final disposal technologies (e.g.
landfilling vs. incineration). However, a comprehensive assessment of the impacts of waste collection and transport was still
lacking. In the present study, we use LCA to evaluate the potential impact of the provincial waste management plan of Varese
(northern Italy). Particular attention is devoted to the estimation of environmental impacts generated during waste transport.
Materials and methods A detailed Life Cycle Inventory was built for the transportation phase, based on primary data collected by interviewing the
agencies involved in waste collection. To model the recycling and final disposal phase we relied on the BUWAL 250 database.
Impacts were evaluated with the Eco-Indicator 99 method in its egalitarian formulation.
Results The results of our analysis reveal that the major potential impacts of the plan are associated with waste collection and transport.
These impacts are partially compensated by reduced resource consumption through recycling and energy recovery through incineration.
Discussion The outputs of the LCIA were compared with those obtained by using other ecoindicators (Eco-Indicator 99 hierarchist and individualist,
CML2, EPS2000). Although not comparable on a quantitative basis, they are qualitatively consistent.
Conclusions Neglecting the effects of collection and transport might result in a severe underestimation of the environmental impacts of
a waste management system, especially as refers to depletion of fossil fuels, emission of respiratory inorganics and climate
change. To reduce the environmental impact of waste management systems, an accurate optimisation of waste transport is required.
Recommendations and perspectives Effective waste management planning requires the explicit inclusion of waste collection and transport when comparing alternative
management policies. 相似文献
3.
基于混合生命周期评价(Hybrid life cycle assessment,HLCA)提出一种改进生态效率模型,系统评价卫生填埋、卫生填埋⁃填埋气利用、焚烧发电、堆肥+卫生填埋和堆肥+焚烧发电5种我国典型生活垃圾处理情景的生态效率,并探究可持续性包含的环境、经济和社会多维权衡关系。结果表明,具有最大生态效率的生活垃圾处理情景因可持续性维度选取不同而异,如考虑人体健康损害影响,焚烧发电情景具有最大经济生态效率,而卫生填埋⁃填埋气利用情景具有最大社会生态效率。生活垃圾处理系统的可持续性评价维度之间具有显著的权衡关系,忽略某些影响类型可能带来问题转移。5种生活垃圾处理情景的环境影响各异,非焚烧情景气候变化影响和焚烧情景人体毒性影响突出。机器设备和燃料使用对资源消耗影响贡献最大,而生活垃圾处理过程对经济效益和其他环境影响贡献最大。本文提出的改进生态效率模型可以定量评价生活垃圾管理系统生态效率及权衡关系,为有效制定生活垃圾管理政策提供全面的信息支持。 相似文献
4.
Grazia Barberio Patrizia Buttol Paolo Masoni Simona Scalbi Fernanda Andreola Luisa Barbieri Isabella Lancellotti 《Journal of Industrial Ecology》2010,14(2):200-216
This article presents the results of an experimental activity aimed at investigating the technical feasibility and the environmental performance of using municipal solid waste incineration bottom ash to produce glass frit for ceramic glaze (glaze frit). The process includes an industrial pretreatment of bottom ash that renders the material suitable for use in glaze frit production and allows recovery of aluminum and iron. The environmental performance of this treatment option is assessed with the life cycle assessment (LCA) methodology. The goal of the LCA study is to assess and compare the environmental impacts of two scenarios of end of life of bottom ash from municipal solid waste incineration (MSWI): landfill disposal (conventional scenario) and bottom ash recovery for glaze frit production (innovative scenario). The main results of the laboratory tests, industrial simulations, and LCA study are presented and discussed, and the environmental advantages of recycling versus landfill disposal are highlighted. 相似文献
5.
我国生活垃圾产量大但处理能力不足,产生多种环境危害,对其资源化利用能够缓解环境压力并回收资源。为探讨生活垃圾资源化利用策略,综合生命周期评价与生命周期成本分析方法,建立生态效率模型。以天津市为例,分析和比较焚烧发电、卫生填埋-填埋气发电、与堆肥+卫生填埋3种典型生活垃圾资源化利用情景的生态效率。结果表明,堆肥+卫生填埋情景具有潜在最优生态效率;全球变暖对总环境影响贡献最大,而投资成本对经济影响贡献最大。考虑天津市生活垃圾管理现状,建议鼓励发展生活垃圾干湿组分分离及厨余垃圾堆肥的资源化利用策略。 相似文献
6.
David Rochat Claudia R. Binder Jaime Diaz Olivier Jolliet 《Journal of Industrial Ecology》2013,17(5):642-655
Three assessment methods, material flow analysis (MFA), life cycle analysis (LCA), and multiattribute utility theory (MAUT) are systematically combined for supporting the choice of best end‐of‐life scenarios for polyethylene terephthalate (PET) waste in a municipality of a developing country. MFA analyzes the material and energy balance of a firm, a region, or a nation, identifying the most relevant processes; LCA evaluates multiple environmental impacts of a product or a service from cradle to grave; and MAUT allows for inclusion of other aspects along with the ecological ones in the assessment. We first systematically coupled MFA and LCA by defining “the service offered by the total PET used during one year in the region” as the functional unit. Inventory and impacts were calculated by multiplying MFA flows with LCA impacts per kilogram. We used MAUT to include social and economic aspects in the assessment. To integrate the subjective point of view of stakeholders in the MAUT, we normalized the environmental, social, and economic variables with respect to the magnitude of overall impacts or benefits in the country. The results show large benefits for recycling scenarios from all points of view and also provide information about waste treatment optimization. The combination of the three assessment methods offers a powerful integrative assessment of impacts and benefits. Further research should focus on data collection methods to easily determine relevant material flows. LCA impact factors specific to Colombia should be developed, as well as more reliable social indicators. 相似文献
7.
Identifying Stakeholders’ Views on the Eco‐efficiency Assessment of a Municipal Solid Waste Management System 下载免费PDF全文
Grégoire Meylan Michael Stauffacher Pius Krütli Roman Seidl Andy Spoerri 《Journal of Industrial Ecology》2015,19(3):490-503
Life cycle assessment (LCA) is one of the most popular methods of technical‐environmental assessment for informing environmental policies, as, for instance, in municipal solid waste (MSW) management. Because MSW management involves many stakeholders with possibly conflicting interests, the implementation of an LCA‐based policy can, however, be blocked or delayed. A stakeholder assessment of future scenarios helps identify conflicting interests and anticipate barriers of sustainable MSW management systems. This article presents such an approach for Swiss waste glass‐packaging disposal, currently undergoing a policy review. In an online survey, stakeholders (N = 85) were asked to assess disposal scenarios showing different LCA‐based eco‐efficiencies with respect to their desirability and probability of occurrence. Scenarios with higher eco‐efficiency than the current system are more desirable and considered more probable than those with lower eco‐efficiency. A combination of inland recycling and downcycling to foam glass (insulation material) in Switzerland is desired by all stakeholders and is more eco‐efficient than the current system. In contrast, institutions of MSW management, such as national and regional environmental protection agencies, judge a scenario in which nearly all cullet would be recycled in the only Swiss glass‐packaging factory as more desirable than supply and demand stakeholders of waste glass‐packaging. Such a scenario involves a monopsony rejected by many municipalities and scrap traders. Such an assessment procedure can provide vital information guiding the formulation of environmental policies. 相似文献
8.
Chalita Liamsanguan Shabbir H. Gheewala 《The International Journal of Life Cycle Assessment》2007,12(7):529-536
Background, Aims and Scope During the combustion of municipal solid waste (MSW), energy is produced which can be utilized to generate electricity. However,
electricity production from incineration has to be evaluated from the point view of the environmental performance. In this
study, environmental impacts of electricity production from waste incineration plant in Thailand are compared with those from
Thai conventional power plants.
Methods The evaluation is based on a life cycle perspective using life cycle assessment (LCA) as the evaluation tool. Since MSW incineration
provides two services, viz., waste management and electricity production, the conventional power production system is expanded
to include landfilling without energy recovery, which is the most commonly used waste management system in Thailand, to provide
the equivalent function of waste management.
Results The study shows that the incineration performs better than conventional power plants vis-à-vis global warming and photochemical
ozone formation, but not for acidification and nutrient enrichment.
Discussion There are some aspects which may influence this result. If landfilling with gas collection and flaring systems is included
in the analysis along with conventional power production instead of landfilling without energy recovery, the expanded system
could become more favorable than the incineration in the global warming point of view. In addition, if the installation of
deNOx process is employed in the MSW incineration process, nitrogen dioxide can be reduced with a consequent reduction of acidification
and nutrient enrichment potentials. However, the conventional power plants still have lower acidification and nutrient enrichment
potentials.
Conclusions The study shows that incineration could not play the major role for electricity production, but in addition to being a waste
management option, could be considered as a complement to conventional power production. To promote incineration as a benign
waste management option, appropriate deNOx and dioxin removal processes should be provided. Separation of high moisture content waste fractions from the waste to be
incinerated and improvement of the operation efficiency of the incineration plant must be considered to improve the environmental
performance of MSW incineration.
Recommendations This study provides an overall picture and impacts, and hence, can support a decision-making process for implementation of
MSW incineration. The results obtained in this study could provide valuable information to implement incineration. But it
should be noted that the results show the characteristics only from some viewpoints.
Outlook Further analysis is required to evaluate the electricity production of the incineration plant from other environmental aspects
such as toxicity and land-use. 相似文献
9.
Julian Cleary 《The International Journal of Life Cycle Assessment》2014,19(9):1607-1622
Purpose
The oft-cited waste hierarchy is considered an important rule of thumb to identify preferential waste management options and places waste prevention at the top. Nevertheless, it has been claimed that waste prevention can sometimes be less favorable than recycling because (1) recycling decreases only the primary production of materials, whereas waste prevention may reduce a combination of both primary and low-impact secondary production, and (2) waste prevention decreases the quantity of material recycled downstream and the avoided impacts associated with recycling. In response to this claim, this study evaluates the life cycle effects of waste prevention activities (WPAs) on a residential waste management system.Methods
This life cycle assessment (LCA) contrasts the net impacts of a large residential solid waste management system (including sanitary landfilling, anaerobic digestion, composting, and recycling) with a system that incorporates five WPAs, implemented at plausible levels (preventing a total of 3.6 % of waste generation tonnage) without diminishing product service consumption. WPAs addressed in this LCA reduce the collected tonnage of addressed advertising mail, disposable plastic shopping bags, newspapers, wine and spirit packaging, and yard waste (grass).Results and discussion
In all cases, the WPAs reduce the net midpoint and endpoint level impacts of the residential waste management system. If WPAs are incorporated, the lower impacts from waste collection, transportation, sorting, and disposal as well as from the avoided upstream production of goods, more than compensate for the diminished net benefits associated with recycling and the displaced electricity from landfill gas utilization.Conclusions
The results substantiate the uppermost placement of waste prevention within the waste hierarchy. Moreover, further environmental benefits from waste prevention can be realized by targeting WPAs at goods that will be landfilled and at those with low recycled content. 相似文献10.
Comparative life cycle assessments of incineration and non-incineration treatments for medical waste
Wei Zhao Ester van der Voet Gjalt Huppes Yufeng Zhang 《The International Journal of Life Cycle Assessment》2009,14(2):114-121
Background, aim, and scope Management of the medical waste produced in hospitals or health care facilities has raised concerns relating to public health,
occupational safety, and the environment. Life cycle assessment (LCA) is a decision-supporting tool in waste management practice;
but relatively little research has been done on the evaluation of medical waste treatment from a life cycle perspective. Our
study compares the environmental performances of two dominant technologies, hazardous waste incineration (HWI) as a type of
incineration technology and steam autoclave sterilization with sanitary landfill (AL) as a type of non-incineration technology,
for specific medical waste of average composition. The results of this study could support the medical waste hierarchy.
Materials and methods This study implemented the ISO 14040 standard. Data on steam autoclave sterilization were obtained from an on-site operations
report, while inventory models were used for HWI, sanitary landfill, and residues landfill. Background data were from the
ecoinvent database. The comparative LCA was carried out for five alternatives: HWI with energy recovery efficiencies of 0%,
15%, and 30% and AL with energy recovery efficiencies of 0% and 10%.
Results The assumptions on the time frame for landfill markedly affect the impact category scores; however, the orders of preference
for both time frames are almost the same. HWI with 30% energy recovery efficiency has the lowest environmental impacts for
all impact categories, except freshwater ecotoxicity. Incineration and sanitary landfill processes dominate global warming,
freshwater aquatic ecotoxicity, and eutrophication of incineration and non-incineration alternatives, respectively. Dioxin
emissions contribute about 10% to human toxicity in HWI without energy recovery alternatives, and a perturbation analysis
yielded identical results. As regards eutrophication, non-incineration treatments have an approximately sevenfold higher impact
than incineration treatments.
Discussion The differences between short-term and long-term time frame assumptions mainly are decided by heavy metals dissolved in the
future leachate. The high heat value of medical waste due to high contents of biomass, plastic, and rubber materials and a
lower content of ash, results in a preference for incineration treatments. The large eutrophication difference between incineration
and non-incineration treatments is caused by different N element transformations. Dioxin emission from HWI is not the most
relevant to human toxicity; however, large uncertainties could exist.
Conclusions From a life cycle perspective, the conventional waste hierarchy, implying incineration with energy recovery is better than
landfill, also applies to the case of medical waste. The sanitary landfill process is the key issue in non-incineration treatments,
and HWI and the subsequent residues landfill processes are key issues in incineration treatments.
Recommendations and perspectives Integrating the medical waste hierarchy and constructing a medical waste framework require broader technologies to be investigated
further, based on a life cycle approach.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
11.
Martin C. Heller Susan E. M. Selke Gregory A. Keoleian 《Journal of Industrial Ecology》2019,23(2):480-495
Scrutiny of food packaging environmental impacts has led to a variety of sustainability directives, but has largely focused on the direct impacts of materials. A growing awareness of the impacts of food waste warrants a recalibration of packaging environmental assessment to include the indirect effects due to influences on food waste. In this study, we model 13 food products and their typical packaging formats through a consistent life cycle assessment framework in order to demonstrate the effect of food waste on overall system greenhouse gas (GHG) emissions and cumulative energy demand (CED). Starting with food waste rate estimates from the U.S. Department of Agriculture, we calculate the effect on GHG emissions and CED of a hypothetical 10% decrease in food waste rate. This defines a limit for increases in packaging impacts from innovative packaging solutions that will still lead to net system environmental benefits. The ratio of food production to packaging production environmental impact provides a guide to predicting food waste effects on system performance. Based on a survey of the food LCA literature, this ratio for GHG emissions ranges from 0.06 (wine example) to 780 (beef example). High ratios with foods such as cereals, dairy, seafood, and meats suggest greater opportunity for net impact reductions through packaging‐based food waste reduction innovations. While this study is not intended to provide definitive LCAs for the product/package systems modeled, it does illustrate both the importance of considering food waste when comparing packaging alternatives, and the potential for using packaging to reduce overall system impacts by reducing food waste. 相似文献
12.
13.
“Discharge of treated wastewater and sewage sludge landfilling” are the most common practice, which poses threats to the local environment. In this work we first constructed a general sewage treatment ecosystem (STE) which integrated the three systems. Emergy synthesis, with several improved emergy-based indicators which considered the waste input contribution and impacts of emissions, was applied to evaluate two alternative scenarios (scenario 1: sewage treatment system + treated water discharge + sludge landfilling; scenario 2: sewage treatment subsystem + reclaimed water reuse subsystem + aerobic compost production subsystem) for Mingjingtan sewage treatment plant in Wanzhou City of Chongqing in China. Results point out the environmental pressure of scenario 2 is much smaller than scenario 1 although its economic performance is somewhat poorer than scenario 1, and finally the sustainability of scenario 2 is still much better than scenario 1. Therefore, the treated water and sewage sludge reuse can further improve the environmental benefit of the sewage treatment process; however, the STE should be optimized in order to enhance its economic benefit. The proposed methods can help policy-makers make decisions and guide designers and operators to improve the comprehensive performance of sewage treatment processes. In addition, this paper also briefly discusses wastewater integrated management strategy. 相似文献
14.
Ivan Muñoz Joan Rieradevall Xavier Domènech Cristina Gazulla 《The International Journal of Life Cycle Assessment》2006,11(5):323-334
Goal, Scope and Background The new European legislation concerning End-of-Life Vehicles (ELVs) will allow, in 2015, the landfilling of only 5% of the
average vehicle weight, which means that the automotive industry must make a great effort in order to design their products
taking into account their recyclability when they become waste. In the present work, LCA is used to assess an existing automotive
component, a plastic door panel, and to compare it with a designed-for-recycling prototype panel, based on compatible polyolefins.
Main Features A \\\'cradle to grave\\\' LCA is carried out for the panel currently produced and the prototype. The following scenarios
are analyzed for plastic waste: landfilling (current practice in Spain), energy recovery in a MSW incinerator or in a cement
kiln, and mechanical recycling.
Results and Discussion The production and use phases together contribute more than 95% in most impact indicators. When the current and prototype
products are compared, a decrease in the environmental impact appears for the prototype in the production phase and also at
end-of-life if recycling is considered with full substitution of virgin polymers. The overall impact reduction ranges from
18% in the toxicity indicators to 80% in landfill use. Energy recovery in cement kilns appears as a good alternative to recycling
in some indicators, such as landfill use or resource depletion. A sensitivity analysis is performed on the quality of recycled
plastic, and the results suggest that the benefits of recycling are substantially reduced if full substitution is not achieved.
Conclusion LCA has been shown to be a very useful tool to validate from an environmental point of view a redesigned automotive component;
in addition, it has allowed one to identify not only the benefits from increased recyclability, but also improvements in other
life cycle phases which were not previously expected.
Recommendation and Perspective From this case study several recommendations to the company have been drawn in order to design environmentally friendly components
for car interiors, and ecodesign is expected to be introduced in the company procedures.
- Glossary
ABS: Acrilonitrile-butadiene-styrene; ASR: Automobile shredder residue; DEHP: Di(ethylhexyl)phtalate; ELV: End-of-life vehicles;
EPDM: Ethylene propylene diene monomer; MSW: Municipal solid waste; MSWI: Municipal solid waste incinerator; NEDC: New European
driving cycle; PA GF: Polyamide glass fiber reinforced; PE: Polyethylene; PES: Polyester; POM: Polyoxymethylene; PP T16: Polypropylene
16% talc filled; PUR: Polyurethane; PVC: Polyvinyl chloride; TPO: Thermoplastic olefin 相似文献
15.
The digestibility of a starch-polyvinyl alcohol (PVOH) biopolymer insulated cardboard coolbox was investigated under a defined anaerobic digestion (AD) system with key parameters characterized. Laboratory results were combined with industrial operational data to develop a site-specific life cycle assessment (LCA) model. Inoculated with active bacterial trophic groups, the anaerobic biodegradability of three starch-PVOH biopolymers achieved 58-62%. The LCA modeling showed that the environmental burdens of the starch-PVOH biopolymer packaging under AD conditions on acidification, eutrophication, global warming and photochemical oxidation potential were dominated by atmospheric emissions released from substrate degradation and fuel combustion, whereas energy consumption and infrastructure requirements were the causes of abiotic depletion, ozone depletion and toxic impacts. Nevertheless, for this bio-packaging, AD of the starch-PVOH biopolymer combined with recycling of the cardboard emerged as the environmentally superior option and optimization of the energy utilization system could bring further environmental benefits to the AD process. 相似文献
16.
Mir Abbas Bozorgirad Hao Zhang Karl R. Haapala Ganti S. Murthy 《The International Journal of Life Cycle Assessment》2013,18(8):1502-1512
Purpose
Municipal solid waste (MSW) can be handled with several traditional management strategies, including landfilling, incineration, and recycling. Ethanol production from MSW is a novel strategy that has been proposed and researched for practical use; however, MSW ethanol plants are not widely applied in practice. Thus, this study has been conducted to analyze and compare the environmental and economic performance of incineration and ethanol production as alternatives to landfilling MSW.Methods
The ISO 14040 life cycle assessment framework is employed to conduct the environmental impact assessment of three different scenarios for the two MSW management strategies based on processing 1 ton of MSW as the functional unit. The first scenario models the process of incinerating MSW and recovering energy in the form of process heat; the second scenario also includes the process of incinerating MSW but yields in the recovery of energy in the form of electricity; and the third scenario models the process of converting MSW into ethanol. The economic impacts of each scenario are then assessed by performing benefit-to-cost ratio (BCR) and net present value (NPV) analyses.Results and discussion
The results from the environmental impact assessment of each scenario reveal that scenario 2 has the highest benefits for resource availability while scenario 3 is shown to be the best alternative to avoid human health and ecosystems diversity impacts. Scenario 1 has the worst environmental performance with respect to each of these environmental endpoint indicators and has net environmental impacts. The results of the economic analysis indicate that the third scenario is the best option with respect to BCR and NPV, followed by scenarios 2 and 1, respectively. Furthermore, environmental and economic analysis results are shown to be sensitive to MSW composition.Conclusions
It appears municipalities should prefer MSW incineration with electricity generation or MSW-to-ethanol conversion over MSW incineration with heat recovery as an alternative to landfilling. The contradiction between the environmental impact assessment results and economic analysis results demonstrates that the decision-making process is sensitive to a broad set of variables. Decisions for a specific MSW management system are subject to facility location and size, MSW composition, energy prices, and governmental policies. 相似文献17.
Alberta Carpenter Jenna R. Jambeck Kevin Gardner Keith Weitz 《Journal of Industrial Ecology》2013,17(3):396-406
A life cycle assessment (LCA) of various end‐of‐life management options for construction and demolition (C&D) debris was conducted using the U.S. Environmental Protection Agency's Municipal Solid Waste Decision Support Tool. A comparative LCA evaluated seven different management scenarios using the annual production of C&D debris in New Hampshire as the functional unit. Each scenario encompassed C&D debris transport, processing, separation, and recycling, as well as varying end‐of‐life management options for the C&D debris (e.g., combustion to generate electricity versus landfilling for the wood debris stream and recycling versus landfilling for the nonwood debris stream) and different bases for the electricity generation offsets (e.g., the northeastern U.S. power grid versus coal‐fired power generation). A sensitivity analysis was also conducted by varying the energy content of the C&D wood debris and by examining the impact of basing the energy offsets on electricity generated from various fossil fuels. The results include impacts for greenhouse gas (GHG) emissions, criteria air pollutants, ancillary solid waste production, and organic and inorganic constituents in water emissions. Scenarios with nonwood C&D debris recycling coupled with combustion of C&D wood debris to generate electricity had lower impacts than other scenarios. The nonwood C&D debris recycling scenarios where C&D wood debris was landfilled resulted in less overall impact than the scenarios where all C&D debris was landfilled. The lowest impact scenario included nonwood C&D debris recycling with local combustion of the C&D wood debris to generate electricity, providing a net gain in energy production of more than 7 trillion British thermal units (BTU) per year and a 130,000 tons per year reduction in GHG emissions. The sensitivity analysis revealed that for energy consumption, the model is sensitive to the energy content of the C&D wood debris but insensitive to the basis for the energy offset, and the opposite is true for GHG emissions. 相似文献
18.
Robert Jan Saft 《The International Journal of Life Cycle Assessment》2007,12(4):230-238
Goal, Scope and Background Life Cycle Assessment (LCA) remains an important tool in Dutch waste management policies. In 2002 the new National Waste Management
Plan 2002–2012 (NWMP) became effective. It was supported by some 150 LCA studies for more than 20 different waste streams.
The LCA results provided a benchmark level for new waste management technologies. Although not new, operational techniques
using combined pyrolysis/gasification are still fairly rare in Europe. The goal of this study is to determine the environmental
performance of the only full scale pyrolysis/gasification plant in the Netherlands and to compare it with more conventional
techniques such as incineration. The results of the study support the process of obtaining environmental permits.
Methods In this study we used an impact assessment method based on the guidelines described by the Centre of Environmental Science
(CML) of Leiden University. The functional unit is defined as treatment of 1 ton of collected hazardous waste (paint packaging
waste). Similar to the NWMP, not only normalized scores are presented but also 7 aggegated scores. All interventions from
the foreground process (land use, emissions, final waste) are derived directly from the site with the exception of emissions
to soil which were calculated. Interventions are accounted to each of the different waste streams by physical relations.
Data from background processes are taken from the IVAM LCA database 4.0 mostly originating from the Swiss ETH96 database and
adapted to the Dutch situation. Allocation was avoided by using system enlargement. The study has been peer reviewed by an
external expert.
Results and Discussion It was possible to determine an environmental performance for the pyrolysis/ gasification of paint packaging waste. The Life
Cycle Inventory was mainly hampered by the uncertainty occurred with estimated air emissions. Here several assumptions had
to be made because several waste inputs and two waste treatment installations profit from one flue gas cleaning treatment
thus making it difficult to allocate the emission values from the flue gasses.
Compared to incineration in a rotary kiln, pyrolysis/gasification of hazardous waste showed better scores for most of the
considered impact categories. Only for the impact categories biodiversity and life support the incineration option proved
favorable due to a lower land use.
Several impact categories had significant influence on the conclusions: acidification, global warming potential, human toxicity
and terrestrial ecotoxicity. The first three are related to a better energy efficiency for pyrolysis/gasification leading
to less fossil energy consumption. Terrestrial ecotoxicity in this case is related to specific emissions of mercury and chromium
(III).
A sensitivity analysis has been performed as well. It was found that the environmental performance of the gasification technique
is sensitive to the energy efficiency that can be reached as well as the choice for the avoided fossil energy source. In this
study a conservative choice for diesel oil was made whereas a choice for heavy or light fuel oil would further improve the
environmental profile.
Conclusions Gasification of hazardous waste has a better environmental performance compared to the traditional incineration in rotary
kilns mainly due to the high energy efficiency. As was determined by sensitivity analysis the differences in environmental
performance are significant. Improvement options for a better performance are a decrease of process emissions (especially
mercury) and a further improvement of the energy balance by decreasing the electricity consumption for shredders and oxygen
consumption or making more use of green electricity.
Recommendations and Perspectives Although the life cycle inventory was sufficiently complete, still some assumptions had to be made in order to establish sound
mass balances on the level of individual components and substances. The data on input of waste and output of emissions and
final waste were not compatible. It was recommended that companies put more emphasis on data storage accounted to particular
waste streams. This is even more relevant since more companies in the future are expected to include life cycle impacts in
their environmental performance. 相似文献
19.
Lucia Rigamonti Mario Grosso Maria Caterina Sunseri 《The International Journal of Life Cycle Assessment》2009,14(5):411-419
Background, aim, and scope Life cycle assessment (LCA) applied to alternative waste management strategies is becoming a commonly utilised tool for decision
makers. This LCA study analyses together material and energy recovery within integrated municipal solid waste (MSW) management
systems, i.e. the recovery of materials separated with the source-separated collection of MSW and the energy recovery from
the residual waste. The final aim is to assess the energetic and environmental performance of the entire MSW management system
and, in particular, to evaluate the influence of different assumptions about recycling on the LCA results.
Materials and methods The analysis uses the method of LCA and, thus, takes into account that any recycling activity influences the environment not
only by consuming resources and releasing emissions and waste streams but also by replacing conventional products from primary
production. Different assumptions about the selection efficiencies of the collected materials and about the quantity of virgin
material substituted by the reprocessed material were made. Moreover, the analysis considers that the energy recovered from
the residual waste displaces the same quantity of energy produced in conventional power plants and boilers fuelled with fossil
fuels.
Results The analysis shows, in the expanded model of the material and energy recovering chain, that the environmental gains are higher
than the environmental impacts. However, when we reduce the selection efficiencies by 15%, the impact indicators worsen by
a percentage included between 10% and 26%. This phenomenon is even more evident when we consider a substitution ratio of 1:<1
for paper and plastic: The worsening is around 15–20% for all the impact indicators except for the global warming for which
the worsening is up to 45%.
Discussion Hypotheses about the selection efficiencies of the source-separated collected materials and about the substitution ratio have
a great influence on the LCA results. Consequently, policy makers have to be aware of the fact that the impacts of an integrated
MSW management system are highly dependent on the assumptions made in the modelling of the material recovery, as well as in
the modelling of the energy recovery.
Conclusions LCA allows to evaluate the impacts of integrated systems and how these impacts change when the assumptions made during the
modelling of the different single parts of the system are modified. Due to the significant impacts that hypotheses about material
recovery have in the results, they should be expressed in a very transparent way in the report of LCA studies, together with
the assumptions made about energy recovery.
Recommendations and perspectives The results suggest that the hypotheses about the value of the substitution ratio are very important, and the case of wood
should therefore be better analysed and a substitution ratio of 1:<1 should be used, as for paper and plastic. It seems that
the assumptions made about which material is replaced by the recycled one are very important too, and in this sense, more
research is needed about what the recycled plastic may effectively substitute, in particular the polyolefin mix. 相似文献
20.
Are future recycling benefits misleading? Prospective life cycle assessment of lithium-ion batteries
Life cycle assessment (LCA) quantifies the whole-life environmental impacts of products and is essential for helping policymakers and manufacturers transition toward sustainable practices. However, typical LCA estimates future recycling benefits as if it happens today. For long-lived products such as lithium-ion batteries, this may be misleading since there is a considerable time gap between production and recycling. To explore this temporal mismatch problem, we apply future electricity scenarios from an integrated assessment model—IMAGE—using “premise” in Brightway2 to conduct a prospective LCA (pLCA) on the global warming potential of six battery chemistries and four recycling routes. We find that by 2050, electricity decarbonization under an RCP2.6 scenario mitigates production impacts by 57%, so to reach zero-carbon batteries it is important to decarbonize upstream heat, fuels, and direct emissions. For the best battery recycling case, data for 2020 gives a net recycling benefit of −22 kg CO2e kWh−1 which reduces the net impact of production and recycling from 71 to 49 kg CO2e kWh−1. However, for recycling in 2040 with decarbonized electricity, net recycling benefits would be nearly 75% lower (−6 kg CO2e kWh−1), giving a net impact of 65 kg CO2e kWh−1. This is because materials recycled in the future substitute lower-impact processes due to expected electricity decarbonization. Hence, more focus should be placed on mitigating production impacts today instead of relying on future recycling. These findings demonstrate the importance of pLCA in tackling problems such as temporal mismatch that are difficult to capture in typical LCA. 相似文献