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1.

Purpose

In the transportation sector, reducing vehicle weight is a cornerstone strategy to improve the fuel economy and energy efficiency of road vehicles. This study investigated the environmental implications of lightweighting two automotive parts (Ford Taurus front end bolster, Chevrolet Trailblazer/GMC Envoy assist step) using glass-fiber reinforced polymers (GFRP) instead of steel alloys.

Methods

The cradle-to-grave life cycle assessments (LCAs) for these studies consider a total service life of 150,000 miles for two applications: a 46 % lighter GFRP bolster on the 2010 Ford Taurus that replaced the 2008 steel and GFRP bolster, and a 51 % lighter GFRP running board for the 2007 Chevrolet Trailblazer/GMC Envoy that replaced the previous steel running board including its polymer fasteners. The life cycle stages in these critically reviewed and ISO-compliant LCA studies include the production of upstream materials and energy, product manufacturing, use, and the end-of-life treatment for all materials throughout the life cycle.

Results and discussion

The results show that the lighter GFRP products performed better than the steel products for global warming potential and primary energy demand for both case studies. In addition, the GFRP bolster performed better for acidification potential. The savings of fuel combustion and production during the use stage of a vehicle far outweigh the environmental impacts of manufacturing or end-of-life. An even greater benefit would be possible if the total weight reduction in the vehicle would be high enough to allow for the reduction of engine displacement or an elongation of gear ratio while maintaining constant vehicle dynamics. These so-called secondary measures allow the fuel savings per unit of mass to be more than doubled and are able to offset the slightly higher acidification potential of the GFRP running board which occurs when only the mass-induced fuel savings are considered.

Conclusions

The lightweight GFRP components are shown to outperform their steel counterparts over the full life cycle mainly due to the reduced fuel consumption of the vehicle in the use phase. To harvest the benefits of light weighting to their full extent, it is recommended that the sum of all mass reductions in the design process be monitored and, whenever feasible, invested into fuel economy by adapting the drive train while maintaining constant vehicle performance rather than leveraging the weight reduction to improve vehicle dynamics.  相似文献   

2.
Goal, scope and background  The industrial packages sector has great importance for the transport sector in Europe. These containers, mainly wooden pallets and spools, are subject to European legislation, which promotes their reuse and recycling. This study uses life cycle assessment (LCA) to assess the environmental impact of the current management system in this sector and the benefits and drawbacks of different reuse intensities as a waste prevention strategy as opposed to the recycling option. Materials and methods  In this paper, four case studies located in Spain and representative of the wooden package sector in Europe are analysed: high reuse pallet, low reuse pallet, low reuse spool and null reuse spool. For the LCA study cases, the functional unit is that required to satisfy the transport necessity of 1,000 t by road. The impact and energy consumption assessment methods used are CML 2 Baseline 2000 and Cumulative Energy Demand. Data are mostly provided by the leading enterprises and organisations in this sector. Results  The paper provides, as a first result, a comprehensive inventory of the systems under study. Secondly, our assessment shows that the systems with higher reuse intensity show a reduction in energy and wood consumption and all the environmental impact categories except for the global warming potential from 34.0% to 81.0% in the pallet study cases and from 50.4% to 72.8% in the spool ones. This reduction is at the expense of the maintenance stage, which on the contrary increases its impact, although it is still relatively small—less than 7% in all the impact categories and flow indicators of the study cases. The highest impact stages are transport, raw material extraction and the process chain. The final disposal and maintenance stages are the lowest impact, contributing at most to less than 30% of the impact in the pallet study cases and 10% in the spool cases. Discussion  Wood consumption (WC), directly related to the number of containers needed to satisfy the functional unit, is the main factor in determining the impact of the stages, especially in the raw materials extraction and process chain stages, assuming that these are undertaken with the same technologies in all the case studies. Other variables, such as the management system, the maintenance index and the final disposal scenario, affect the impact of the remaining stages: transport, maintenance and final disposal. The global warming potential results obtained demonstrate the environmental benefits of using containers made of a renewable resource such as wood instead of using other materials, but these results are not expected to prioritise the lower reuse systems because of their better performance in this category. Conclusions  Reuse, a strategy capable of reducing the environmental impacts of the wooden container systems, is preferable to recycling, while the package maintenance tasks are still feasible. Therefore, reuse, combined with recycling as final disposal, should be encouraged to reduce the demand for natural resources and the waste generated. Recommendations  Based on these results, attention should be paid to the maintenance stage, which, being the lowest-impact one, could substantially reduce the impact of the remaining stages.  相似文献   

3.
Anaerobic biodegradation of cyanide under methanogenic conditions   总被引:1,自引:0,他引:1  
Upflow, anaerobic, fixed-bed, activated charcoal biotreatment columns capable of operating at free cyanide concentrations of greater than 100 mg liter-1 with a hydraulic retention time of less than 48 h were developed. Methanogenesis was maintained under a variety of feed medium conditions which included ethanol, phenol, or methanol as the primary reduced carbon source. Under optimal conditions, greater than 70% of the inflow free cyanide was removed in the first 30% of the column height. Strongly complexed cyanides were resistant to removal. Ammonia was the nitrogen end product of cyanide transformation. In cell material removed from the charcoal columns, [14C]bicarbonate was the major carbon end product of [14C]cyanide transformation.  相似文献   

4.
Summary A stable enrichment of bacteria capable of metabolizing lactate under methanogenic conditions was obtained from rumen contents. The methanogenic strains associated with lactate utilizers were identified asMethanosarcina sp. andMethanobacterium sp. The role of propionate as indicator of failure in the methanogenic phase is shown.
Dégradation microbienne du lactate sous des conditions méthanigènes
Résumé Un enrichissement stable de bactéries capables de métaboliser le lactate dans des conditions méthanigènes a été isolé du contenu de rumen. Les souches méthanigènes, associées avec les utilisateurs de lactate, ont été identifiées comme appartenant aux genresMethanosarcina etMethanobacterium. Le rôle du propionate comme indicateur de la faillite de la phase méthanigène a été démontré.
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5.
Wooden and plastic pallets are used extensively in global trade to transport finished goods and products. This article compares the life cycle performance of treated wooden and plastic pallets through a detailed cradle‐to‐grave life cycle assessment (LCA), and conducts an analysis of the various phytosanitary treatments. The LCA investigates and evaluates the environmental impacts due to the resources consumed and emissions of the product throughout its life cycle. The environmental impacts of the pallets are compared on a one‐trip basis and a 100,000‐trips basis. Impact categories are chosen with respect to environmental concerns. The results show that on a one‐trip basis, wooden pallets with conventional and radio frequency (RF) heat treatment incur an overall carbon footprint of 71.8% and 80.3% lower, respectively, than plastic pallets during their life cycle; and in comparison with wooden pallets treated with methyl bromide fumigation, they incur 20% and 30% less overall carbon footprint. Theoretical calculations of the resource consumption and emissions of RF treatment of pallets suggest that dielectric technology may provide a lower‐carbon alternative to both current ISPM 15‐approved treatments and to plastic pallets. Methyl bromide fumigation (15.95 kg CO2 equivalent [eq.]) has a larger carbon footprint than conventional heat treatment (12.69 kg CO2 eq.) of pallets. For the 100,000‐trips basis, the differences are even more significant. The results recommend that wooden pallets are more environmentally friendly than plastic pallets, and conventional and RF heat treatment for wooden pallets is more sustainable than methyl bromide fumigation treatment.  相似文献   

6.
Upflow, anaerobic, fixed-bed, activated charcoal biotreatment columns capable of operating at free cyanide concentrations of greater than 100 mg liter-1 with a hydraulic retention time of less than 48 h were developed. Methanogenesis was maintained under a variety of feed medium conditions which included ethanol, phenol, or methanol as the primary reduced carbon source. Under optimal conditions, greater than 70% of the inflow free cyanide was removed in the first 30% of the column height. Strongly complexed cyanides were resistant to removal. Ammonia was the nitrogen end product of cyanide transformation. In cell material removed from the charcoal columns, [14C]bicarbonate was the major carbon end product of [14C]cyanide transformation.  相似文献   

7.
Kinetics were determined for methanogenic activity and chlorinated ethylene dehalogenation by a methanol-enriched, anaerobic sediment consortium. The culture reductively dechlorinated perchloroethylene (PCE) to trichloroethylene (TCE), 1,1-dichloroethylene (1,1-DCE), vinylchloride (VC), and ethylene and ethane. The absence : of methanol or the addition of 2-bromoethanesulfonic. acid in the presence of methanol suppressed both methanogenic activity and dechlorination. In contrast, acetate production continued in the presence of 2-bromoethanesulfonic acid. These results suggest that dechlorination was strongly linked to methane formation and not to acetate production. A kinetic model, developed to describe both methanogenesis and dechlorination, successfully predicted experimentally measured concentrations of biomass, methane, substrate, and chlorinated ethylenes. The average maximum specific dehalogenation rates for PCE, TCE, 1,1-DCE, and VC were 0.9 +/- 0.6, 0.4 +/- 0.1, 12 +/- 0.1, and 2.5 +/- 1.7 mumol contaminant/ g. DW/day, respectively. This pattern for dechlorination rates is distinctly different than that reported for transition metal cofactors, where rates drop by approximately one order of magnitude as each successive chlorine is removed. The experimental results and kinetic analysis suggest that it will be impractical to targeting methanol consuming methanogenic organisms for in situ ground-water restoration. (c) 1995 John Wiley & Sons, Inc.  相似文献   

8.
Conversion of indole to oxindole under methanogenic conditions   总被引:2,自引:0,他引:2  
When indole was incubated under methanogenic conditions with an inoculum of sewage sludge, the chemical was metabolized with 10 days and temporary formation of an intermediate was observed. The metabolite was isolated by thin-layer chromatography and determined to be 1,3-dihydro-2H-indol-2one (oxindole) by UV spectroscopy (lambdaMAX, 247 nm) and mass spectrometry (m/z, 133). The methane produced (net amount) indicated nearly complete mineralization of indole.  相似文献   

9.
This study was intended to evaluate the environmental impact, and potential improvements for a typical tractor model (LT360D) of LG Machinery Co., Ltd. The life cycle of this study includes all stages from raw material acquisition up to final disposal. The eco-indicator 95 method was employed to perform an impact assessment. The result of this study is expected to represent the environmental feature of typical diesel vehicles at each life cycle stage. This study is a starting point of building life cycle inventories for typical off-road diesel tractors. With this result, environmental weak points of the tractor have been defined, and major improvement strategies have been set up to develop the ‘Green Tractor’.  相似文献   

10.
Conversion of indole to oxindole under methanogenic conditions.   总被引:4,自引:4,他引:4       下载免费PDF全文
When indole was incubated under methanogenic conditions with an inoculum of sewage sludge, the chemical was metabolized with 10 days and temporary formation of an intermediate was observed. The metabolite was isolated by thin-layer chromatography and determined to be 1,3-dihydro-2H-indol-2one (oxindole) by UV spectroscopy (lambdaMAX, 247 nm) and mass spectrometry (m/z, 133). The methane produced (net amount) indicated nearly complete mineralization of indole.  相似文献   

11.

Purpose

India’s biofuel programme relies on ethanol production from sugarcane molasses. However, there is limited insight on environmental impacts across the Indian ethanol production chain. This study closes this gap by assessing the environmental impacts of ethanol production from sugarcane molasses in Uttar Pradesh, India. A comparative analysis with south-central Brazilian sugarcane ethanol is also presented to compare the performance of sugarcane molasses-based ethanol with sugarcane juice-based ethanol.

Methods

The production process is assessed by a cradle-to-gate life cycle assessment. The multifunctionality problem is solved by applying two variants of system expansion and economic allocation. Environmental impacts are assessed with Impact 2002+ and results are presented at the midpoint level for greenhouse gas emissions, non-renewable energy use, freshwater eutrophication and water use. Furthermore, results include impacts on human health and ecosystem quality at the damage level. Sensitivity analysis is also performed on key contributing parameters such as pesticides, stillage treatment and irrigation water use.

Results and discussion

It is found that, compared to Brazilian ethanol, Indian ethanol causes lower or comparable greenhouse gas emissions (0.09–0.64 kgCO2eq/kgethanolIN, 0.46–0.63 kgCO2eq/kgethanolBR), non-renewable energy use (?0.3–6.3 MJ/kgethanolIN, 1–4 MJ/kgethanolBR), human health impacts (3.6?·?10?6 DALY/kgethanolIN, 4?·?10?6 DALY/kgethanolBR) and ecosystem impairment (2.5 PDF?·?m2?·?year/kgethanolIN, 3.3 PDF?·?m2?·?year/kgethanolBR). One reason is that Indian ethanol is exclusively produced from molasses, a co-product of sugar production, resulting in allocation of the environmental burden. Additionally, Indian sugar mills and distilleries produce surplus electricity for which they receive credits for displacing grid electricity of relatively high CO2 emission intensity. When economic allocation is applied, the greenhouse gas emissions for Indian and Brazilian ethanol are comparable. Non-renewable energy use is higher for Indian ethanol, primarily due to energy requirements for irrigation. For water use and related impacts, Indian ethanol scores worse due groundwater irrigation, despite the dampening effect of allocation. The variation on greenhouse gas emissions and non-renewable energy use of Indian mills is much larger for high and low performance than the respective systems in Brazil.

Conclusions

Important measures can be taken across the production chain to improve the environmental performance of Indian ethanol production (e.g. avoiding the use of specific pesticides, avoiding the disposal of untreated stillage, transition to water efficient crops). However, to meet the targets of the Indian ethanol blending programme, displacement effects are likely to occur in countries which export ethanol. To assess such effects, a consequential study needs to be prepared.  相似文献   

12.
The International Journal of Life Cycle Assessment - To support the needs of downstream users of zircon sand and other industry stakeholders, the Zircon Industry Association (ZIA) conducted an...  相似文献   

13.

Purpose

To support the data requirements of stakeholders, the Nickel Institute (NI) conducted a global life cycle impact assessment (LCIA) to show, with indicators, the potential environmental impacts of the production of nickel and ferronickel from mine to refinery gate. A metal industry wide agreed approach on by-products and allocation was applied.

Methods

Nine companies, comprising 19 operations, contributed data, representing 52 % of global nickel metal production and 40 % of global ferronickel production. All relevant pyro- and hydrometallurgical production routes were considered, across most major nickel-producing regions. Data from Russia, the biggest nickel-producing nation, was included; the Chinese industry did not participate. 2011 was chosen as reference year for data collection. The LCIA applied allocation of impacts of by-products using both economic and mass allocations. A sensitivity analysis was conducted to further understand the relevance and impact of the different allocation approaches.

Results and discussion

The primary extraction and refining steps are the main contributors to primary energy demand (PED) and global warming potential (GWP), contributing 60 and 70 % to the PED for the production of 1 kg class I nickel and 1 kg nickel in ferronickel, respectively, and over 55 % of the GWP for both nickel products. The PED for 1 kg class 1 nickel was calculated to be 147 MJ, whilst the PED for 1 kg nickel in ferronickel was calculated to be three times higher at 485 MJ. The main factors influencing energy demand in the metallurgical processes are ore grade and ore mineralogy. Sulphidic ore is less energy intensive to process than oxidic ore. Eighty-six percent of the production volume from class 1 nickel producers, in this study, is from sulphidic ore. All ferronickel was produced from oxidic ore. The LCIA results, including a sensitivity analysis of the impact of producers with higher and lower PED, reflect the influence of the production route on energy demand and on environmental impact categories.

Conclusions

Conformant to relevant ISO standards, and backed-up with a technical and critical review, this LCIA quantifies the environmental impacts associated with the production of the main nickel products. With this study, a sound background dataset for downstream users of nickel has been provided. The Nickel Institute aims to update their data in the coming years to reflect upon changes in technology, energy efficiency, and raw material input.
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14.
Pesticides are biologically active substances that are directly released to the environment during the use phase of their life cycle. Pesticides are widely used and play an important role in the production of vital goods such as food, feedstuffs and cotton. The Discussion Forum 19 focused on the impact assessment of pesticides applied in agriculture. The discussion forum started with three talks about new approaches to estimate pesticide emissions and to assess their fate in the environment. The following short presentations illustrated the application of some of these methods in case studies and highlighted the problem of data availability. The last two presentations provided insight into risk assessment models used for pesticide registration from a company perspective and from the viewpoint of the authorities.  相似文献   

15.

Purpose

This study performs an exploratory comparative evaluation of various animal and vegetable protein and lipid sources, used as feed in the aquaculture industry. The ingredients studied include fishmeal (FM) and fish oil (FO) from fisheries by-products, meal and fat by-products from poultry slaughter, FM and FO from Peruvian anchovy capture, and soybean meal and oil. The boundaries studied include the production or capture, the ingredient processing unit and the transport to the unit that processes the ingredients into aquafeeds in Portugal.

Methods

The LCA impact assessment method is the CML-IA baseline V3.04/EU25 and the results were obtained for the characterisation step. Some of the inventory data were collected from a Portuguese company (Savinor) that processes both by-products from local fisheries and by-products from poultry production. Savinor provided data specifically associated with the ingredients’ production. Obtained data were complemented with literature data from: fish capture and poultry production. Inventory data for the production of ingredients from Peruvian anchovy and soybeans were retrieved from literature. It was assumed that the transport of the ingredients produced from Peruvian anchovy, between Lima and Rotterdam, is made in a transoceanic vessel, and it is considered a transport by truck between Rotterdam and Ovar, for soybean ingredients and FM/FO produced from Peruvian anchovy.

Results and discussion

This paper shows that poultry meal and poultry fat from poultry slaughter by-products have the larger contribution to all environmental impact categories evaluated, being the production of poultry the life cycle stage that contributes most to the overall categories. On the other hand, FM and FO from Peruvian anchovy were the ingredients with a lower contribution to all impact categories, except for abiotic depletion category, for FM from Peruvian anchovy, and abiotic depletion, abiotic depletion (fossil fuels) and ozone layer depletion for FO from Peruvian anchovy. For these categories, soybean meal and oil had lower impacts, respectively. The ingredients were compared by classes (protein and lipid sources).

Conclusions

A general conclusion is that soybean meal and oil and FM/FO from Peruvian anchovy appear to be very interesting options for aquafeeds from an LCA perspective. However, some limitations identified for this study, as, for instance, that it does not account for the environmental benefits associated with the use of the mentioned by-products, that would otherwise be considered wastes (i.e. by-products from the fish canning sector and poultry slaughter) shall be evaluated in future studies.
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16.

Background Aims and Scope  

Sustainability was adopted by UNEP in Rio de Janeiro (1992) as the main political goal for the future development of humankind. It should also be the ultimate aim of product development. According to the well known interpretation of the original definition given in the Brundtland report, sustainability comprises three components: environment, economy and social aspects. These components or “pillars” of sustainability have to be properly assessed and balanced if a new product is to be designed or an existing one is to be improved.  相似文献   

17.

Purpose

Pulp and paper manufacturing constitutes one of the largest industry segments in term of water and energy usage and total discharges to the environment. More than many other industries, however, this industry plays a key role in sustainable development because its most important raw material, wood fiber, is renewable Dias and Houtman (Environ Prog 23(4):347?C357, 2004). Actually, even if the communication is dominated by electronic media, paper-based communication has a role to play due to its unique practical and aesthetic qualities. This research aims to assess the environmental impact of advertising folders produced with different papers and distributed by a system of Italian consumers?? cooperatives in order to indicate the possible options of improvement and to assess the CO2 (eq) emitted during the entire life cycle.

Methods

Life cycle assessment (LCA) was performed from cradle-to-grave considering paper production, transport from paper mill to printing site, printing, distribution, and disposal. Data for the study were directly collected from specific companies and completed on the basis of literature information. The analysis was conducted using the SimaPro 7.1.5 software and IMPACT 2002+ method to assess all its environmental impact and damage categories.

Results and discussion

LCA analysis indicates that the higher environmental impact is mainly due to paper production and printing processes. The main operations which generate the major impact in the paper production stage are related to the direct or indirect fossil energy use, the production of additives for bleaching operations, and the collection and selection of waste paper. Printing causes relevant impacts for the electricity and ink production and for the aluminum plates used in the offset printing. Moreover, the use of paper with low quantity of additives and small amount of primary fibers causes a reduction of the environmental load of 13.94?%. The major global warming potential value was found for advertising folders made with little amount of mechanical pulp which slightly contributes to the absorption of CO2.

Conclusions

The analysis pointed out the relevance of the paper production phase and of the printing step within the advertising folders life cycle and allowed to detect the other critical stages of the life cycle. Paper composition greatly affects the environmental impact of the advertising folders?? life cycle.  相似文献   

18.
The International Journal of Life Cycle Assessment - Packaging can be a critical aspect in the environmental performance of pharmaceutical products; however, few life cycle assessment studies were...  相似文献   

19.
Purpose

Ferro niobium (FeNb) is a metallic alloy whose industrial use has been increasing steadily in the last decades. This work aims to systematize the available information on FeNb production, provide its inventory data and generate its first technologically representative publicly available life cycle impact assessment (LCIA).

Methods

The production of 1 kg of FeNb from pyrochlore in the baseline year 2017 was modelled following a cradle-to-gate approach. Primary information on mass, energy and water flows was collected when possible from the Brazilian leading FeNb supplier, CBMM (80% of the world market). The CML method (CML-IA 4.7) was applied for the impact assessment including global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), ozone layer depletion potential (ODP), abiotic depletion potential (fossil and elemental) (ADPfossil and ADPelemental) and photochemical ozone creation potential (POCP).

Results and discussion

The first stage of pyrochlore processing (pyrochlore ore extraction, mechanical processing and flotation) and the last stage (aluminothermic reaction) bear the highest impact in all analyzed CML impact categories. The primary aluminium consumption has the most important contribution in five out of seven impact categories (50% in ADPfossil, 55% in AP, 35% in EP, 57% in GWP and 40% in POCP). In this sense, the industry should promote a higher share of secondary aluminium in the production process. Also, the impact from electricity consumption and processing chemicals showed to be relevant.

Conclusions

This work is the first LCIA on ferro niobium to be published with representative, high-quality data. A dataset was produced in order to enable ferro niobium to be incorporated to future LCIA-modelling.

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20.
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