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1.
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
2.
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3.
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
4.
Volrad Wollny Günter Dehoust Uwe R. Fritsche Peter Weinem 《Journal of Industrial Ecology》2001,5(3):49-63
Plastics recycling, especially as prescribed by the German Ordinance on Packaging Waste (Verpackungsverordnung), is a conspicuous example of closing material loops on a large scale. In Germany, an industry‐financed system (Duales System Deutschland) was established in 1991 to collect and recycle packaging waste from households. To cope with mixed plastics, various “feedstock‐recycling” processes were developed. We discuss the environmental benefits and the cost‐benefit ratio of the system relative to municipal solid waste (MSW) incineration, based on previously published life‐cycle assessment (LCA) studies. Included is a first‐time investigation of energy recovery in all German incinerators, the optimization opportunities, the impact on energy production and substitution processes, an estimation of the costs, and a cost‐benefit assessment. In an LCA, the total environmental impact of MSW incineration is mainly determined by the energy recovery ratio, which was found on average to reach 39% in current German incineration plants. Due to low revenues from additional energy generation, it is not cost‐effective to optimize the plants energetically. Energy from plastic incineration substitutes for a specific mixture of electric base‐load power, district heating, and process steam generation. Any additional energy from waste incineration will replace, in the long term, mainly natural gas, rather than coal. Incineration of plastic is compared with feedstock recycling methods in different scenarios. In all scenarios, the incineration of plastic leads to an increase of CO2 emissions compared to landfill, whereas feedstock recycling reduces CO2 emissions and saves energy resources. The costs of waste incineration are assumed to decrease by about 30% in the medium term. Today, the calculated costs of CO2 reduction in feedstock recycling are very high, but are ex‐pected to decline in the near future. Relative to incineration, the costs for conserving energy via feedstock recycling are 50% higher, but this gap will close in the near future if automatic sorting and processing are implemented in Germany. 相似文献
5.
Joan Rieradevall Xavier Domènech Pere Fullana 《The International Journal of Life Cycle Assessment》1997,2(3):141-144
A case study of a life-cycle assessment (LCA) is performed concerning the treatment of household solid wastes in a landfill.
The stages considered in this LCA study are: goal and scope definition, inventory analysis and impact assessment. The data
of the inventory include the consumption of raw materials and energy through the transport of wastes and the management of
landfill, and the corresponding emissions to the environment. Abiotic resource depletion, global warming, acidification, eutrophication
and human toxicological impacts have been considered as impact categories for the impact assessment phase of the LCA. A comparison
of the environmental impact of the landfilling with and without energy recovery is carried out.
Members of the Spanish Association for LCA Development (APRODACV) 相似文献
6.
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
7.
Almudena Hospido Teresa Moreira María Martín Miquel Rigola Gumersindo Feijoo 《The International Journal of Life Cycle Assessment》2005,10(5):336-345
Background, Aims and Scope Huge amounts of sewage sludge, that need to be handled, are generated all around the world from wastewater treatment plants
and its management in an economically and environmentally acceptable way has become a matter of increasing importance during
the last few years.
In this paper, we make use of Life Cycle Assessment (LCA) to compare biological and thermal processes, that is to say, anaerobic
digestion versus pyrolysis and incineration. This paper will complete the analysis performed in a wastewater treatment plant,
where sludge post-treatment was identified as one of the main contributors to the environmental impact on the global system.
Methods LCA is a tool for evaluating the environmental performance of goods as well as processes or services (collectively termed
products). ISO 14040 defines LCA as a compilation and evaluation of the inputs, outputs and the potential environmental impacts
of a system throughout its life cycle: from the production of raw materials to the disposal of the waste generated.
In this study, data relating to the actual scenario from an existent wastewater treatment plant were considered. Both bibliographical
and real data from existing facilities were used for the thermal processes proposed.
The Centre of Environmental Science (CML) of Leiden University's methodology was chosen to quantify the potential environmental
impacts associated with the different scenarios under study. The software SimaPro 5.1 was used and CML factors (updated in
2002) were chosen for characterisation and normalisation stages.
Results and Discussion In a previous study, sewage sludge was found to be a critical point in the environmental performance of a wastewater treatment
plant, so different alternatives have been tackled here. Anaerobic digestion followed by land application of pasty sludge
comprises both energy recovery and nutrient recovery. Other thermal processes, such as incineration or pyrolysis, allow energy
recovery (both electrical and thermal) and, although nutrients are lost, new co-products are produced (tar and char at pyrolysis).
Here, the most adverse case (that is to say, the total amount of heavy metals is supposed to be released from the sludge and
reach the environment) was applied to consider the most negative impact due to sludge spreading in agricultural soils; so
more research is required in order to establish the precise amount of heavy metals that is effectively uptaken by the plants
and crops as well as the amount that is transferred to another phase as a leachate.
Thermal processes are presented here as a good option to recover energy from the sludge; although the value of nutrients is
lost. Tar and char, co-products from pyrolysis, are good examples that were evaluated here, recycling of bottom ashes from
sludge incineration or manufacture of ceramic materials from sludge are other options to be studied in the near future.
Conclusion During the last few years, several opinions have been declared in favour of land application, incineration or pyrolysis,
but many voices have also spoken out against each one. To obtain general conclusions for an overall comparison of different
post-treatment of urban wastewater sludge is not easy as there are many contradictory aspects. The most effective utilisation
of sewage sludge implies both energy and material re-use, but this is not always possible. Nevertheless, we think that land
application of digested sludge is an acceptable option, probably not the best but at least a good one, for sludge treatment
as long as efforts are focused on the minimisation of heavy metal content in the final cake. 相似文献
8.
Purpose
This paper compares 16 waste lubricant oil (WLO) systems (15 management alternatives and a system in use in Portugal) using a life cycle assessment (LCA). The alternatives tested use various mild processing techniques and recovery options: recycling during expanded clay production, recycling and electric energy production, re-refining, energy recovery during cement production, and energy recovery during expanded clay production.Methods
The proposed 15 alternatives and the actual present day situation were analyzed using LCA software UMBERTO 5.5, applied to eight environmental impact categories. The LCA included an expansion system to accommodate co-products.Results
The results show that mild processing with low liquid gas fuel consumption and re-refining is the best option to manage WLO with regard to abiotic depletion, eutrophication, global warming, and human toxicity environmental impacts. A further environmental option is to treat the WLO using the same mild processing technique, but then send it to expanded clay recycling to be used as a fuel in expanded clay production, as this is the best option regarding freshwater sedimental ecotoxicity, freshwater aquatic ecotoxicity, and acidification.Conclusions
It is recommended that there is a shift away from recycling and electric energy production. Although sensitivity analysis shows re-refining and energy recovery in expanded clay production are sensitive to unit location and substituted products emission factors, the LCA analysis as a whole shows that both options are good recovery options; re-refining is the preferable option because it is closer to the New Waste Framework Directive waste hierarchy principle. 相似文献9.
Andréa Oliveira Nunes Luciano Rodrigues Viana Pierre-Marie Guineheuc Virgínia Aparecida da Silva Moris Jane Maria Faulstich de Paiva Radu Barna Yannick Soudais 《The International Journal of Life Cycle Assessment》2018,23(9):1825-1838
Purpose
Carbon fibers have been widely used in composite materials, such as carbon fiber-reinforced polymer (CFRP). Therefore, a considerable amount of CFRP waste has been generated. Different recycling technologies have been proposed to treat the CFRP waste and recover carbon fibers for reuse in other applications. This study aims to perform a life cycle assessment (LCA) to evaluate the environmental impacts of recycling carbon fibers from CFRP waste by steam thermolysis, which is a recycling process developed in France.Methods
The LCA is performed by comparing a scenario where the CFRP waste is recycled by steam-thermolysis with other where the CFRP waste is directly disposed in landfill and incineration. The functional unit set for this study is 2 kg of composite. The inventory analysis is established for the different phases of the two scenarios considered in the study, such as the manufacturing phase, the recycling phase, and the end-of-life phase. The input and output flows associated with each elementary process are standardized to the functional unit. The life cycle impact assessment (LCIA) is performed using the SimaPro software and the Ecoinvent 3 database by the implementation of the CML-IA baseline LCIA method and the ILCD 2011 midpoint LCIA method.Results and discussion
Despite that the addition of recycling phase produces non-negligible environmental impacts, the impact assessment shows that, overall, the scenario with recycling is less impactful on the environment than the scenario without recycling. The recycling of CFRP waste reduces between 25 and 30% of the impacts and requires about 25% less energy. The two LCIA methods used, CML-IA baseline and ILCD 2011 midpoint, lead to similar results, allowing the verification of the robustness and reliability of the LCIA results.Conclusions
The recycling of composite materials with recovery of carbon fibers brings evident advantages from an environmental point of view. Although this study presents some limitations, the LCA conducted allows the evaluation of potential environmental impacts of steam thermolysis recycling process in comparison with a scenario where the composites are directly sent to final disposal. The proposed approach can be scaled up to be used in other life cycle assessments, such as in industrial scales, and furthermore to compare the steam thermolysis to other recycling processes.10.
Comparative LCA of treatment options for US scrap tires: material recycling and tire-derived fuel combustion 总被引:1,自引:0,他引:1
Rebe Feraldi Sarah Cashman Melissa Huff Lars Raahauge 《The International Journal of Life Cycle Assessment》2013,18(3):613-625
Purpose
This life cycle assessment (LCA) study compares two prevalent end-of-life (EOL) treatment methods for scrap tires: material recycling and energy recovery. The primary intended use of the study results is to inform stakeholders of the relative environmental burdens and trade-offs associated with these two EOL vehicle tire treatment methods. The study supports prioritization of the waste treatment hierarchy for this material stream in the US.Methods
This LCA compares (1) material recycling through ambient-temperature mechanical processing and (2) energy recovery through co-incineration of both whole and preprocessed scrap tires at a cement kiln. The avoided burden recycling methodology reflects the substitution of virgin synthetic rubber used in asphalt modification with the ground tire rubber from material recycling and the substitution of conventional kiln fuels with the tire-derived fuel (TDF). Both attributional (ALCA) and consequential (CLCA) methodologies are used: the ALCA assesses the environmental profiles of the treatment methods and the CLCA examines the potential effects of shifting more scrap tires to material recycling. The attributional portion of the LCA study was conducted in accordance with ISO standards 14044 series.Results
The results in both methodological approaches indicate that the material recycling scenario provides greater impact reductions than the energy recovery scenario in terms of the examined environmental impact potentials: energy demand, iron ore consumption, global warming potential, acidification, eutrophication, smog formation, and respiratory effects. The additional impact reductions from material recycling are significant, and the establishment of new infrastructure required for a shift to material recycling incurs relatively insignificant burdens. Sensitivity analyses indicate that this conclusion does not change for (1) a range of TDF heating values, (2) a decrease in the mixed scrap tire rubber-to-steel composition ratio, (3) two alternative electricity grid fuel mixes with higher and lower carbon dioxide emission rankings than that of the baseline scenario, or (4) a comparison of material recycling to energy recovery when TDF is used in pulp and paper mills instead of cement kilns.Conclusions
These results provide a basis for more informed decision-making when prioritizing scrap tire waste treatment hierarchy. 相似文献11.
Life cycle assessment of Australian automotive door skins 总被引:1,自引:0,他引:1
Prateek Puri Paul Compston Victor Pantano 《The International Journal of Life Cycle Assessment》2009,14(5):420-428
Background, aim, and scope Policy initiatives, such as the EU End of Life Vehicle (ELV) Directive for only 5% landfilling by 2015, are increasing the
pressure for higher material recyclability rates. This is stimulating research into material alternatives and end-of-life
strategies for automotive components. This study presents a Life Cycle Assessment (LCA) on an Australian automotive component,
namely an exterior door skin. The functional unit for this study is one door skin set (4 exterior skins). The material alternatives
are steel, which is currently used by Australian manufacturers, aluminium and glass-fiber reinforced polypropylene composite.
Only the inputs and outputs relative to the door skin production, use and end-of-life phases were considered within the system
boundary. Landfill, energy recovery and mechanical recycling were the end-of-life phases considered. The aim of the study
is to highlight the most environmentally attractive material and end-of-life option.
Methods The LCA was performed according to the ISO 14040 standard series. All information considered in this study (use of fossil
and non fossil based energy resources, water, chemicals etc.) were taken up in in-depth data. The data for the production,
use and end-of-life phases of the door skin set was based upon softwares such as SimaPro and GEMIS which helped in the development
of the inventory for the different end-of-life scenarios. In other cases, the inventory was developed using derivations obtained
from published journals. Some data was obtained from GM-Holden and the Co-operative research Centre for Advanced Automotive
Technology (AutoCRC), in Australia. In cases where data from the Australian economy was unavailable, such as the data relating
to energy recovery methods, a generic data set based on European recycling companies was employed. The characterization factors
used for normalization of data were taken from (Saling et. al. Int J Life Cycle Assess 7(4):203–218 2002) which detailed the method of carrying out an LCA.
Results The production phase results in maximum raw material consumption for all materials, and it is higher for metals than for the
composite. Energy consumption is greatest in the use phase, with maximum consumption for steel. Aluminium consumes most energy
in the production phase. Global Warming Potential (GWP) also follows a trend similar to that of energy consumption. Photo
Oxidants Creation Potential (POCP) is the highest for the landfill scenario for the composite, followed by steel and aluminium.
Acidification Potential (AP) is the highest for all the end-of-life scenarios of the composite. Ozone Depletion Potential
(ODP) is the highest for the metals. The net water emissions are also higher for composite in comparison to metals despite
high pollution in the production phases of metallic door skins. Solid wastes are higher for the metallic door skins.
Discussion The composite door skin has the lowest energy consumption in the production phase, due to the low energy requirements during
the manufacturing of E-glass and its fusion with polypropylene to form sheet molding compounds. In general, the air emissions
during the use phase are strongly dependent on the mass of the skins, with higher emissions for the metals than for the composite.
Material recovery through recycling is the highest in metals due to efficient separation techniques, while mechanical recycling
is the most efficient for the composite. The heavy steel skins produce the maximum solid wastes primarily due to higher fuel
consumption. Water pollution reduction benefit is highest in case of metals, again due to the high efficiency of magnetic
separation technique in the case of steel and eddy current separation technique in the case of aluminium. Material recovery
in these metals reduces the amount of water needed to produce a new door skin set (water employed mainly in the ingot casting
stage). Moreover, the use of heavy metals, inorganic salts and other chemicals is minimized by efficient material recovery.
Conclusions The use of the studied type of steel for the door skins is a poor environmental option in every impact category. Aluminium
and composite materials should be considered to develop a more sustainable and energy efficient automobile. In particular,
this LCA study shows that glass-fiber composite skins with mechanical recycling or energy recovery method could be environmentally
desirable, compared to aluminium and steel skins. However, the current limit on the efficiency of recycling is the prime barrier
to increasing the sustainability of composite skins.
Recommendations and perspectives The study is successful in developing a detailed LCA for the three different types of door skin materials and their respective
recycling or end-of-life scenarios. The results obtained could be used for future work on an eco-efficiency portfolio for
the entire car. However, there is a need for a detailed assessment of toxicity and risk potentials arising from each of the
four different types of door skin sets. This will require greater communication between academia and the automotive industry
to improve the quality of the LCA data. Sensitivity analysis needs to be performed such as the assessment of the impact of
varying substitution factors on the life cycle of a door skin. Incorporation of door skin sets made of new biomaterials need
to be accounted for as another functional unit in future LCA studies.
Discussion contributions to this article from the readership would the highly welcome. The authors 相似文献
12.
Goal, Scope and Background Gipuzkoa is a department of the Vasque Country (Spain) with a population of about 700,000 people. By the year 2000 approximately
85% of municipal solid waste in this area was managed by landfilling, and only 15% was recycled. Due to environmental law
restrictions and landfill capacity being on its limit, a planning process was initiated by the authorities. LCA was used,
from an environmental point of view, to assess 7 possible scenarios arising from the draft Plan for the 2016 time horizon.
Main Features In each scenario, 9 waste flows are analysed: rest waste, paper and cardboard, glass containers, light packaging, organic-green
waste, as well as industrial/commercial wood, metals and plastics, and wastewater sludge. Waste treatments range from recycling
to energy recovery and landfilling.
Results Recycling of the waste flows separated at the source (paper and cardboard, glass, light packaging, organic-green waste, wood
packaging, metals and plastics) results in net environmental benefits caused by the substitution of primary materials, except
in water consumption. These benefits are common to the 7 different scenarios analysed. However, some inefficiencies are detected,
mainly the energy consumption in collection and transport of low density materials, and water consumption in plastic recycling.
The remaining flows, mixed waste and wastewater sludge, are the ones causing the major environmental impacts, by means of
incineration, landfilling of partially stabilised organic material, as well as thermal drying of sludge. With the characterisation
results, none of the seven scenarios can be clearly identified as the most preferable, although, due to the high recycling
rates expected by the Plan, net environmental benefits are achieved in 9 out of 10 impact categories in all scenarios when
integrated waste management is assessed (the sum of the 9 flows of waste). Finally, there are no relevant differences between
scenarios concerning the number of treatment plants considered. Nevertheless, only the effects on transportation impacts were
assessed in the LCA, since the plant construction stage was excluded from the system boundaries.
Conclusions The results of the study show the environmental importance of material recycling in waste management, although the recycling
schemes assessed can be improved in some aspects. It is also important to highlight the environmental impact of incineration
and landfilling of waste, as well as thermal drying of sludge using fossil fuels. One of the main findings of applying LCA
to integrated waste management in Gipuzkoa is the fact that the benefits of high recycling rates can compensate for the impacts
of mixed waste and wastewater sludge.
Recommendations and Outlook Although none of the scenarios can be clearly identified as the one having the best environmental performance, the authorities
in Gipuzkoa now have objective information about the future scenarios, and a multidisciplinary panel could be formed in order
to weight the impacts if necessary. In our opinion, LCA was successfully applied in Gipuzkoa as an environmental tool for
decision making. 相似文献
13.
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
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
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Background This article describes two projects conducted recently by Sound Resource Management (SRMG) one for the San Luis Obispo County Integrated Waste Management Authority (SLO IWMA) and the other for the Washington State Department of Ecology (WA Ecology). For both projects we used life cycle assessment (LCA) techniques to evaluate the environmental burdens associated with collection and management of municipal solid waste. Both projects compared environmental burdens from curbside collection for recycling, processing, and market shipment of recyclable materials picked up from households and/or businesses against environmental burdens from curbside collection and disposal of mixed solid waste. Method logy. The SLO IWMA project compared curbside recycling for households and businesses against curbside collection of mixed refuse for deposition in a landfill where landfill gas is collected and used for energy generation. The WA Ecology project compared residential curbside recycling in three regions of Washington State against the collection and deposition of those same materials in landfills where landfill gas is collected and flared. In the fourth Washington region (the urban east encompassing Spokane) the WA Ecology project compared curbside recycling against collection and deposition in a wasteto- energy (WTE) combustion facility used to generate electricity for sale on the regional energy grid. During the time period covered by the SLO study, households and businesses used either one or two containers, depending on the collection company, to separate and set out materials for recycling in San Luis Obispo County. During the time of the WA study households used either two or three containers for the residential curbside recycling programs surveyed for that study. Typically participants in collection programs requiring separation of materials into more than one container used one of the containers to separate at least glass bottles and jars from other recyclable materials. For the WA Ecology project SRMG used life cycle inventory (LCI) techniques to estimate atmospheric emissions of ten pollutants, waterborne emissions of seventeen pollutants, and emissions of industrial solid waste, as well as total energy consumption, associated with curbside recycling and disposal methods for managing municipal solid waste. Emissions estimates came from the Decision Support Tool (DST) developed for assessing the cost and environmental burdens of integrated solid waste management strategies by North Carolina State University (NCSU) in conjunction with Research Triangle Institute (RTI) and the US Environmental Protection Agency (US EPA)1. RTI used the DST to estimate environmental emissions during the life cycle of products. RTI provided those estimates to SRMG for analysis in the WA Ecology project2. For the SLO IWMA project SRMG also used LCI techniques and data from the Municipal Solid Waste Life- Cycle Database (Database), prepared by RTI with the support of US EPA during DST model development, to estimate environmental emissions from solid waste management practices3. Once we developed the LCI data for each project, SRMG then prepared a life cycle environmental impacts assessment of the environmental burdens associated with these emissions using the Environmental Problems approach discussed in the methodology section of this article. Finally, for the WA study we also developed estimates of the economic costs of certain environmental impacts in order to assess whether recycling was cost effective from a societal point of view. Conclusions Recycling of newspaper, cardboard, mixed paper, glass bottles and jars, aluminum cans, tin-plated steel cans, plastic bottles, and other conventionally recoverable materials found in household and business municipal solid wastes consumes less energy and imposes lower environmental burdens than disposal of solid waste materials via landfilling or incineration, even after accounting for energy that may be recovered from waste materials at either type disposal facility. This result holds for a variety of environmental impacts, including global warming, acidification, eutrophication, disability adjusted life year (DALY) losses from emission of criteria air pollutants, human toxicity and ecological toxicity. The basic reason for this conclusion is that energy conservation and pollution prevention engendered by using recycled rather than virgin materials as feedstocks for manufacturing new products tends to be an order of magnitude greater than the additional energy and environmental burdens imposed by curbside collection trucks, recycled material processing facilities, and transportation of processed recyclables to end-use markets. Furthermore, the energy grid offsets and associated reductions in environmental burdens yielded by generation of energy from landfill gas or from waste combustion are substantially smaller then the upstream energy and pollution offsets attained by manufacturing products with processed recyclables, even after accounting for energy usage and pollutant emissions during collection, processing and transportation to end-use markets for recycled materials. The analysis that leads to this conclusion included a direct comparison of the collection for recycling versus collection for disposal of the same quantity and composition of materials handled through existing curbside recycling programs in Washington State. This comparison provides a better approximation to marginal energy usage and environmental burdens of recycling versus disposal for recyclable materials in solid waste than does a comparison of the energy and environmental impacts of recycling versus management methods for handling typical mixed refuse, where that refuse includes organics and non-recyclables in addition to whatever recyclable materials may remain in the garbage. Finally, the analysis also suggests that, under reasonable assumptions regarding the economic cost of impacts from pollutant emissions, the societal benefits of recycling outweigh its costs. 相似文献
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A dissolved air flotation (DAF) system upgrade was proposed for an urban paper mill to recycle effluent. To understand the influence of operating variables on the environmental impacts of greenhouse gas (GHG) emissions and water consumption, a dynamic supply chain model was linked with life cycle assessment (LCA) to produce an environmental inventory. Water is a critical natural resource, and understanding the environmental impacts of recycling water is paramount in continued development of sustainable supply chains involving water. The methodology used in this study bridged the gap between detailed process models and static LCA modeling so that operating variables beyond discrete scenario analysis could be investigated without creating unnecessarily complex models. The model performed well in evaluating environmental impacts. It was found that there was no single optimum operating regime for all environmental impacts. For a mill discharging 80 cubic meters of effluent per hour (m3/hour), GHGs could be minimized with a DAF capacity of 17.5 m3/hour, while water consumption could be minimized with a DAF capacity of 25 m3/hour, which allowed insight into where environmental trade‐offs would occur. The study shows that more complexity can be achieved in supply chain modeling without requiring a full technical model. It also illustrates the need to consider multiple environmental impacts and highlights the trade‐off of GHG emissions with water consumption in water recycling. The supply chain model used in this water treatment case study was able to identify the environmental trade‐offs from the operating variables selected. 相似文献
18.
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
19.
Conceptión Jiménez-González Seungdo Kim Michael R. Overcash 《The International Journal of Life Cycle Assessment》2000,5(3):153-159
Life Cycle Assessment (LCA) methodology evaluates holistically the environmental consequences of a product system or activity,
by quantifying the energy and materials used, the wastes released to the environment, and assessing the environmental impacts
of those energy, materials and wastes. Despite the international focus on environmental impact and LCA, the quality of the
underlying life cycle inventory data is at least as, if not more, important than the more qualitative LCA process.
This work presents an option to generate gate-to-gate life cycle information of chemical substances, based on a transparent
methodology of chemical engineering process design (an ab initio approach). In the broader concept of a Life Cycle Inventory
(LCI), the information of each gate-to-gate module can be linked accordingly in a production chain, including the extraction
of raw materials, transportation, disposal, reuse, etc. to provide a full cradle to gate evaluation. The goal of this article
is to explain the methodology rather than to provide a tutorial on the techniques used. This methodology aims to help the
LCA practitioner to obtain a fair and transparent estimate of LCI data when the information is not readily available from
industry or literature. Results of gate-to-gate life cycle information generated using the cited methodology are presented
as a case study.
It has been our experience that both LCI and LCA information provide valuable means of understanding the net environmental
consequence of any technology. The LCI information from this methodology can be used more directly in exploring engineering
and chemistry changes to improve manufacturing processes. The LCA information can be used to set broader policy and to look
at more macro improvements for the environment. 相似文献
20.
Wulf-Peter Schmidt Hans-Martin Beyer 《The International Journal of Life Cycle Assessment》1999,4(2):107-112
A simplified LCA is conducted hased on the methodology of simplified LCAs according to SETAC (Europe). The case study is about
the recovery of automotive battery housings. As a result of the simplified LCA, the current situation of material recycling
is preferred to the past situation of landfilling. However, energy recovery could be an option, too. 相似文献