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1.
The aim of this paper is to understand and to model the environmental performance of biodiesel produced by various Greek raw materials under current conditions. Three energy crops (rapeseed, sunflower and soybean) have been studied, with regard to their levels of biodiesel productivity. Throughout the entire process, current Greek climatic conditions and cultivation parameters have been taken into account. At the stage of assessment, we conclude that the environmental impacts per crop area indicate that soybean has the lowest environmental impacts. However, by assessing the results per quantity of produced biodiesel, the crop with the minimum environmental impacts is sunflower. This paper shows that environmental benefits from biodiesel have better results, compared to conventional diesel, thus leading to the conclusion that it is feasible to succeed improved environmental performance.  相似文献   

2.
This study presents detailed and comprehensive inventories on the horticultural production of tomato using compost (CM) or mineral fertilizers (M), in both open-fields (OF) and greenhouses (GH), providing information on the environmental impacts and assessing the agronomic viability of the four cultivation options. Life cycle assessment (LCA) was used to calculate the potential environmental impacts of the tomato production cycle per ton of product. The stages in the assessment included: mineral and organic fertilizers production, fertilizers transport, cultivation stage and greenhouse stage. The data were obtained experimentally in pilot fields and in an industrial composting facility using municipal organic waste, both located in the Mediterranean area. The results indicate that replacing a fraction of the mineral fertilizers dosage with compost is a good option, as this did not alter yield or fruit size parameters. Greenhouse protection increased infrastructure materials requirements but enhanced harvest by almost 50% and reduced the water and pesticides requirement. Compost production and greenhouse stages were the most impacting stages. Without subtracting the avoided burdens by composting and not dumping organic waste, the cultivation option OF_M had the lowest and OF_CM the highest impact. When avoided burdens were taken into consideration, the environmental impacts of the four cultivation options varied, depending on the impact category, with bigger differences due to fertilization as a variable rather than the production system.  相似文献   

3.
基于LCA方法的水泥企业清洁生产审核   总被引:4,自引:2,他引:4  
水泥行业是典型的高能耗、高污染的工业,其快速发展带来了严重的资源、能源、环境等问题.因此,本文选择生命周期评价方法(LCA)作为清洁生产审核工具,对大连某水泥企业进行了清洁生产审核.本文在调研水泥工艺及现状的基础上,运用生命周期评价方法对水泥生产过程中原料开采、运输、生料制备、煤粉制备、熟料煅烧及水泥粉磨阶段进行清单分析与建模.采用了生命周期评价软件Gabi4进行清单计算与分析,评价模型为CML2001Dec07特征化模型.在整个水泥生产过程中考虑了全球变暖,人体毒性,环境酸化等环境影响类型,得出整个生命周期中石灰石和煤炭的资源能源耗竭潜值和资源消耗量最大,而环境排放影响中熟料煅烧阶段对各个类型的环境影响远远高于其他几个阶段,同时熟料煅烧过程中排放的二氧化碳等温室气体的影响最严重.最终根据评价分析结果确定清洁生产审核重点并提出了清洁生产方案,并且在清洁生产方案中选择其中最重要的余热发电方案,进行余热发电清洁生产方案前后环境影响比较和清洁生产方案量化分析.  相似文献   

4.
A Life Cycle Assessment (LCA) was performed to analyze environmental consequences of different pear production chains in terms of fossil energy use and greenhouse gas (GHG) emission in China. The assessment identified hotspots that contributed significantly to the environmental impacts of pear production from the cradle to the point of sale. The results showed that GHG emissions and fossil energy use varied in the different production chains because the environmental performance does not associate with the farming systems (i.e. organic vs. conventional), but is co-determined by farm topography and thus machinery use, by market demands to seasonality of products and thus the need for storage, and by local farming practices including manure management. The LCA could be used as a tool to guide selections of agricultural inputs with the aim of reducing environmental impacts. The results of the LCA analysis indicate that a list of choices are available to reduce energy use and GHG emission in the pear production chain, namely substitution of the traditional storage systems by an efficiently controlled atmosphere storage system, using manure for biogas production, conversion from the conventional farming to organic farming, and reduction of mechanical cultivation.  相似文献   

5.
The present study analyses the different processes followed during color TV set production along with the energy consumption and the environment emissions in each stage. The purpose is to identify “hot-spots”, i.e. parts of the life cycle important to the total environmental impact. The analysis is performed using life cycle assessment (LCA) methodology, which is a method used to identify and quantify in the environmental performance of a process or a product from “cradle to grave”. LCA methodology provides a quantitative basis for assessing potential improvements in the environmental performance of a system throughout the life cycle. The system investigated includes the production of manufacturing materials, transport of manufacturing materials, color TV set manufacturing, transport of color TV sets, use of color TV sets, discarding color TV sets and partial plastic waste energy utilization. The environmental burdens that arise from color TV sets are mainly due to air emissions derived from fossil fuel utilization.  相似文献   

6.
Paper pulp manufacturing is the main non-food industrial utilization of plant biomass. Non-wood and agricultural residues are potential raw materials in the production of specialty papers. This chapter aims to quantify the environmental impacts associated with non-wood high quality paper pulp manufacture via soda-anthraquinone (AQ) cooking process by means of the application of LCA methodology in a cradle-to-gate analysis. Hemp (Cannabis sativa) and Flax (Linum usitatissimum) were evaluated as raw materials for the production of high quality non-porous pulp. A specialty paper pulp mill was analysed in detail and process chain was divided in six subsystems: agricultural activities, chemicals production, electricity production, transport, pulp production and waste treatment. Inventory data came from interviews and surveys (on-site measurements). When necessary, the data were completed with bibliographic resources.Abiotic resources depletion (AD), global warming (GW), ozone layer depletion (OLD), human toxicity (HT), ecotoxicity, photochemical oxidant formation (POF), acidification (A) and eutrophication (E) were the impact categories analysed in this study. According to the results, the environmental impact is mainly caused by the production of chemicals, electricity and fibres (agricultural activities) due to greenhouse gases emissions, phosphorous and nitrogen compounds emissions. The activities inside the pulp mill present minor contribution to almost all impact categories, excluding GW (15%) and E (6%) as well as OLD (25%). This study provides useful information for non-wood based industries related not only to pulp manufacture but also to panels or biorefineries with the aim of increasing their sustainability.  相似文献   

7.
Global demand for bio-fuels continues unabated. Rising concerns over environmental pollution and global warming have encouraged the movement to alternate fuels, the world ethanol market is projected to reach 86 billion litres this year. Bioethanol is currently produced from land-based crops such as corn and sugar cane. A continued use of these crops drives the food versus fuel debate. An alternate feed-stock which is abundant and carbohydrate-rich is necessary. The production of such a crop should be sustainable, and, reduce competition with production of food, feed, and industrial crops, and not be dependent on agricultural inputs (pesticides, fertilizer, farmable land, water). Marine biomass could meet these challenges, being an abundant and carbon neutral renewable resource with potential to reduce green house gas (GHG) emissions and the man-made impact on climate change. Here we examine the current cultivation technologies for marine biomass and the environmental and economic aspects of using brown seaweeds for bio-ethanol production.  相似文献   

8.
This study assesses the direct and indirect environmental impacts to be expected if Switzerland should replace one percent of its current diesel consumption with imports of A) soybean methyl ester (SME) from Brazil, or B) palm methyl ester (PME) from Malaysia. In order to take into account possible future consequences, what-if scenarios were developed and assessed by means of a consequential LCA. In contrast to attributional LCA, the consequential approach uses system enlargement to include the marginal products affected by a change of the physical flows in the central life cycle. This means that the LCA considers all inputs and outputs which are linked to biodiesel production and that the product system is subsequently expanded to include the marginal products affected. Both future systems are assessed in comparison with the environmental scores of the fossil equivalent to biodiesel, i.e. diesel low in sulphur. The environmental burdens are measured by means of greenhouse gas emissions (GHG), land occupation and various non-aggregated and aggregated environmental impact indicators.In sum, the environmental impacts of an increased SME consumption depend on the environmental scores of the marginal replacement products on the world market, rather than on local production factors. In other words, the marginal products assumed to be affected are most important for the results obtained, i.e. in particular the marginal vegetable oil, fodder cake and land areas. In this study it is SME production increased at the expense of the available soybean oil which shifts the impacts associated with soybean oil production to the production of the marginal vegetable oils on the world market. In this perspective, it is not relevant in which country biodiesel production takes place, but rather which vegetable oil is involved. With respect to PME, the most relevant determining factor for the environmental impacts is the land area affected by the increased cultivation of oil palms. Currently, this expansion displaces primarily peat land and rain forest. This causes GHG emissions which are much higher than the emissions of the fossil reference. All in all, both PME from Malaysia and SME from Brazil cause more environmental impact than allowed by the Swiss tax redemption on agro-biofuels (max. 60% GHG emissions and 125% UBP of the fossil reference).  相似文献   

9.
Life cycle assessment (LCA) has been used to compare inorganic and biological catalysis for the production of biodiesel by transesterification. The inorganic route, using catalysis by sodium hydroxide, has been compared with a conceptual biological one using enzymatic catalysis by the lipase produced by Candida antarctica. Although biological catalysis has not been used for industrial production of biodiesel to date, results from laboratory experiments suggest that it could have distinct advantages over the inorganic route, particularly with regard to a simplified flowsheet for purification and concomitant energy savings. Five flowsheet options have been included in the study to investigate the alkali and enzyme catalysed production routes from rapeseed oil, use of methanol or ethanol for transesterification and the effect of efficiency of alcohol recovery. The LCA shows that the enzymatic production route is environmentally more favourable. Improvements are seen in all impact categories. Global warming, acidification, and photochemical oxidation are reduced by 5%. Certain toxicity levels have more than halved. These results are mainly due to lower steam requirements for heating in the biological process.  相似文献   

10.
Some emerging technologies are expected to be pivotal for solving many of the environmental challenges faced today, especially those related to energy. However, many of these technologies may incur significant environmental impacts over their life cycle, while having environmental benefits during their use. This paper presents results of a Life Cycle Assessment (LCA) of a proposed type of nanophotovoltaic, quantum dot photovoltaic (QDPV) module. The LCA is confined to the stages of raw materials acquisition, manufacturing, and use. The impacts of QDPV are compared with other types of PV modules and energy sources - both renewable and nonrenewable. To provide a comprehensive comparative assessment, QDPV modules were compared with mature as well as emerging PV types for which data are available. Comparative assessment with other types of energy sources includes coal, oil, lignite, natural gas, diesel, nuclear, wind, and hydropower.QDPV modules may have the potential to overcome two current barriers of solar technology: low efficiencies and high manufacturing costs. If higher efficiencies are realized, QDPV modules could pave the way to large scale implementation of solar energy, helping nations move toward greater energy independence. On the other hand, candidate materials as quantum dots for solar cell applications are mostly compound semiconductors such as cadmium selenide, cadmium telluride, and lead sulfide which may be toxic and for which renewable options are limited. Toxic effects of these materials may be exacerbated by their nanoscale features.The LCA was carried out using the software SimaPro, and the Ecoinvent Life Cycle Inventory (LCI) database supplemented with available literature and patent information. Our results indicate that while QDPV modules have shorter Energy PayBack Time (EPBT), lower Global Warming Potential (GWP), SOx and NOx emissions than other types of PV modules, they have higher heavy metal emissions, underscoring the need for investigation of emerging technologies, especially nano-based ones, from a life cycle perspective. QDPV modules are better in all impact categories assessed than carbon-based energy sources but they have longer EPBT than wind and hydropower and higher GWP.  相似文献   

11.
Growing public concerns about the traceability, safety and environmental-friendliness of food products provide an incentive for shorter supply chains in agricultural production. Here, we assessed the environmental impacts of the substitution of imported soybean meal with locally-produced rapeseed meal in French dairy production systems, using a life-cycle approach. Two feeding rations based on either French-produced rapeseed meal or Brazilian-produced soy meal as concentrates, were compared for nine impact categories, including global warming, ecotoxicity and eutrophication. Crop production was the main contributor to most impacts, while overseas transport of soy meal only had a marginal effect. The “Soybean” ration appeared more environmentally-efficient than the “Rapeseed” ration because it involved less intensive management practices, in particular regarding synthetic fertilizers consumption. However, land use changes brought about by soybean cultivation should also be examined.  相似文献   

12.
Single-use medical devices have been under close scrutiny for several years, especially the choice of plastic materials. Many different requirements such as medical safety, treatment functionality and efficiency, environmental performance, etc. have to be fulfilled. Today, the most commonly used materials for hydrophilic urinary catheters are polyvinylchloride (PVC) and thermoplastic polyurethane (TPU). In this research study, these two materials' environmental performance was evaluated. In light of the knowledge gained in that study a new plastic material for use in urinary catheters was developed. The aim of the development of this new material was to design a high performance material with superior environmental performance. The newly developed plastic material is a polyolefin-based elastomer. The ecological environmental performance of the new material was evaluated and compared to the existing plastic materials. The study focused exclusively on the choice of plastic materials and their ecological environmental performance.The analysis has been performed using a system perspective and a life cycle assessment (LCA) methodology. The functional unit has been set to the treatment of one patient during one year. The results from the LCA models have been presented both in terms of direct inventory data, such as energy use and formed emissions, and in terms of the results from four different impact assessment methods. Analysis of the results based on direct inventory data, i.e. common inventory results such as energy resource uses and emissions of CO2, NOx and SO2 show an overall better environmental performance for the new polyolefin-based elastomer compared to the existing PVC and TPU plastic materials. The normalization and weighting steps in the analyzes have indicated the importance of energy resource uses and global warming as indicator for the environmental performance even if other impact categories also can play a role. In the environmental impact assessment, the polyolefin-based elastomer showed a clearly better environmental performance than the TPU material. Compared to PVC plastic material the new polyolefin-based elastomer showed an almost equivalent environmental performance. This can be mainly explained by the different materials' energy use. The new material has thus also shown to be an environmentally good alternative to PVC if a PVC-free material is requested. Basing the plastic formula, on simple bulk plastics with low energy use in the production of single-use medical devices, has been shown to be a successful method of producing high quality products with superior environmental performance.  相似文献   

13.
Increased and intensified pig production has raised the needs for proper management systems of pig manure in order to reduce negative environmental impacts. The objectives of this study were to identify the most significant environmental impacts from pig manure management considering a wide range of impact categories and to determine which integrated technology system at which handling stage can achieve the highest impact reduction. Twelve scenarios applying various treatment, storage and land application systems were developed and compared. Life cycle assessment (LCA) with the aim of capturing the actual consequences of the considered scenarios was selected as the tool for impact quantification. The most important impact categories in this investigation are global warming (GWP), aquatic eutrophication (AEP), respiratory inorganics (RIP), and terrestrial eutrophication (TEP). The two latter impacts, caused by ammonia emissions, have not been widely considered in most of previous LCA studies on pig manure management. The main keys for the effective impact reduction are the integration of treatment technology systems aiming at energy recovery with high nutrient recovery and control of greenhouse gas, ammonia, and nitrate emissions at every handling stage. For GWP and AEP, the anaerobic digestion-based scenario with natural crust storage achieves the highest impact reduction because of high efficiencies in energy and nutrient recovery with restricted emissions of GHG and nitrate. For RIP and TEP, the incineration and thermal gasification based scenarios and the scenario without a treatment system applying the deep injection method yield the highest impact minimisation due to the lowest ammonia emissions. This study further indicates the need to consider all significant impacts to decide the best management options taking into consideration local conditions.  相似文献   

14.
A screening life cycle assessment (LCA) of tomato ketchup has been carried out. The purpose was to identify ‘hot-spots', that is parts of the life-cycle that are important to the total environmental impact. The system investigated includes agricultural production, industrial refining, packaging, transportation, consumption and waste management. Energy use and emissions were quantified and some of the potential environmental effects assessed. Packaging and food processing were found to be hot-spots for many, but not all, of the impact categories investigated. For primary energy use, the storage time in a refrigerator (household phase) was found to be a critical parameter.  相似文献   

15.
Besides the apparent need to reduce greenhouse gas emissions, other important factors contributing to the renewed interest in biofuels are energy security concerns and the need of sustainable transportation fuel. Nearly 30% of the annual CO2 emissions in the U.S. come from the transportation sector and more than half of the fuel is imported. Biofuels appear to be a promising option to reduce carbon dioxide emissions, and the reliance on imported oil concomitantly. The interest on (ligno) cellulosic ethanol is gaining momentum as corn-based ethanol is criticized for using agricultural outputs for fuel production. Among many lignocellulosic feedstocks, woodchips is viewed as one of the most promising feedstocks for producing liquid transportation fuels. The renewable and carbon neutral nature of the feedstocks, similar chemical and physical properties to gasoline, and the low infrastructure cost due to the availability of fuel flex vehicles and transportation networks make (ligno) cellulosic bioethanol an attractive option. An in-depth LCA of woodchips shows that harvesting and woodchips processing stage and transportation to the facility stage emit large amount of environmental pollutants compared to other life cycle stages of ethanol production. Our analysis also found that fossil fuel consumption and respiratory inorganic effects are the two most critical environmental impact categories in woodchips production. We have used Eco-indicator 99 based cradle-to-gate LCA method with a functional unit of 4 m3 of dry hardwood chips production.  相似文献   

16.
Existing product life cycle assessment (LCA) studies on offset printed matter all point at paper as the overall dominating cause of environmental impacts. All studies focus on energy consumption and the dominating role of paper is primarily based on the energy-related impact categories: global warming, acidification and nutrient enrichment. Ecotoxicity and human toxicity, which are related to emissions of chemicals, etc., are only included to a limited degree or not at all. In this paper we include the impacts from chemicals emitted during the life cycle of sheet fed offset printed matter. This is done by making use of some of the newest knowledge about emissions from the production at the printing industry combined with knowledge about the composition of the printing materials used. In cases with available data also upstream emissions from the production of printing materials are included. The results show that inclusion of the chemical emission-related impacts makes the EDIP97 impact profile of sheet fed offset products much more varied, as well for the normalised profiles as for the profiles weighted by distance to political environmental targets. Especially the ecotoxicity impact potential related to the production stage may contribute significantly, and the use of paper no longer becomes the overall dominating factor driving the environmental impacts.  相似文献   

17.
关中平原饲料作物生产的碳足迹及影响因素研究   总被引:1,自引:0,他引:1  
畜牧业是主要的人为温室气体排放源,而饲料作物生产是畜牧业温室气体排放的主要来源之一.研究饲料作物生产的碳足迹及减排措施对于从日粮的角度减少畜牧业的温室气体排放至关重要.因此,本文应用生命周期评价理论和IPCC(2006)田间温室气体计算方法,建立了饲料作物碳足迹评估方法,分析了关中平原饲料作物的温室气体排放特点和减排措施及潜力.结果表明:关中平原主要饲料的碳足迹(以CO_2当量计)由大到小依次为玉米0.620、苜蓿0.382、小麦麸皮0.240、青饲玉米0.217、小麦秸秆0.083和玉米秸秆0.070 kg·kg~(-1);主要排放环节是化肥生产、氮肥田间排放和灌溉,对碳足迹的贡献率分别为26.0%~33.8%、27.8%~29.6%和24.5%~39.1%.由于关中平原存在过量施肥和大水漫灌的现象,通过化肥减施和节水灌溉措施减少饲料作物碳足迹的潜力很大,但不同措施带来的实际减排量仍需通过田间实践和具体技术的生命周期评价进行验证.  相似文献   

18.
北京电动出租车与燃油出租车生命周期环境影响比较研究   总被引:3,自引:2,他引:1  
燃油机动车尾气排放是导致城市包括雾霾在内的大气环境问题的主要来源之一.以电动汽车替代传统燃油车是当前各国解决城市大气污染问题的重要举措.北京于2011年启动了电动出租车推广计划.为比较北京市迷迪电动汽车和现代燃油车生命周期的环境影响,运用生命周期评价方法,基于Ga Bi4.4软件,选用CML2001和EI99影响评价模型对两款车的生产、使用和报废回收全生命周期过程的环境影响进行了定量评价,并针对汽车报废里程和电力能源结构进行了敏感性分析.结果表明,从全生命周期视角,根据EI99评价模型,迷迪电动汽车环境影响总体上优于现代燃油车,尤其在削减化石能源消耗方面优势凸显,但在生态系统质量影响及人体健康影响方面却略有增大的趋势;利用CML2001模型对比分析得出迷迪电动汽车比燃油出租车在对非生物资源消耗、全球变暖以及臭氧层损耗等方面有明显改善;但在生产阶段尤其是动力系统生产方面在非生物资源消耗、酸化、富营养化、全球变暖、光化学臭氧合成、臭氧层损耗、生态毒性等生态环境影响却均有增大趋势.使用阶段电力生产是迷迪电动汽车非生物资源消耗、酸化、富营养化、全球变暖、光化学臭氧合成、生态毒性等环境影响的主要来源;而现代燃油出租车使用阶段的环境影响主要来源于尾气排放和汽油生产,其中尾气排放是造成现代燃油车在富营养化和全球变暖等方面影响潜值较大的主要原因;基于清单数据库,针对致霾因子影响分析得出,在2010年北京市电力能源驱动下,迷迪电动车明显增加了超细颗粒物(PM2.5)、氮氧化物(NOx)、硫氧化物(SOx)、挥发性有机物(volatile organic compouds,VOCs)等因子的全生命周期的排放,而同时降低了氨气(NH3)的排放量,使用阶段排放的差别是造成上述趋势的主要原因.对关键因素敏感性分析发现,随着报废里程以及清洁能源比例的增加,迷迪电动汽车相对现代燃油车的单位里程碳减排量呈现增加的趋势.清洁电力能源的使用可大幅降低迷迪电动汽车致霾污染物的排放量.根据分析结果,为北京市电动车的推广提出了对策建议.  相似文献   

19.
Evaluating both new and existing processes for primary metal production to assess their environmental impacts is often difficult due to the many inputs and outputs involved. Life Cycle Assessment (LCA) is a methodology that can be used for such purposes to identify those parts of the metal production life cycle that have significant environmental impacts. LCA has been used by CSIRO Minerals to assess the “cradle-to-gate” environmental impacts of a number of metal production processes practised either currently or potentially in Australia. The metals considered included copper, nickel, aluminium, lead, zinc, steel, stainless steel and titanium, by both pyrometallurgical and hydrometallurgical routes in some instances. The environmental profile included greenhouse and acid rain gas emissions, solid waste emissions and gross energy consumption. The results for various metals are compared in this paper. New process technologies for primary metal production can be expected to reduce the environmental impacts of metal production, and estimates of likely reductions for technologies involving stainless steel, titanium and aluminium are also presented in this paper.  相似文献   

20.
This paper aims to evaluate the environmental burdens associated with spray dried soluble coffee over its entire life cycle and compare it with drip filter coffee and capsule espresso coffee. It particularly aims to identify critical environmental issues and responsibilities along the whole life cycle chain of spray dried coffee. This life cycle assessment (LCA) specifically uses foreground data obtained directly from coffee manufacturers and suppliers. Aside from energy consumption and greenhouse gases emissions, water footprint is also studied in detail, including regionalization of water impacts based on the ecological scarcity method 2006. Other impact categories are screened using the IMPACT 2002+ impact assessment method.The overall LCA results for a 1 dl cup of spray dried soluble coffee amounts approximately to 1 MJ of primary non-renewable energy consumption, to emissions of 0.07 kg of CO2-eq, and between 3 and 10 l of non-turbined water use, depending on whether or not the coffee cultivation is irrigated and wet treated. When considering turbined water, use can be up to 400 l of water per cup. Pouch – and to a lesser extent metal can packaging alternatives – show lower environmental burdens than glass or sticks.On average, about one half of the environmental footprint occurs at a life cycle stage under the control of the coffee producer or its suppliers (i.e., during cultivation, treatment, processing, packaging up to distribution, along with advertising) and the other half at a stage controlled by the user (shopping, appliances manufacturing, use and waste disposal). Key environmental parameters of spray dried soluble coffee are the amount of extra water boiled and the efficiency of cup cleaning during use phase, whether the coffee is irrigated or not, as well as the type and amount of fertilizer used in the coffee field. The packaging contributes to 10% of the overall life cycle impacts.Compared to other coffee alternatives, spray dried soluble coffee uses less energy and has a lower environmental footprint than capsule espresso coffee or drip filter coffee, the latter having the highest environmental impacts on a per cup basis. This study shows that a broad LCA approach is needed to help industry to minimize the environmental burdens directly related to their products. Including all processes of the entire system is necessary i) to get a comprehensive environmental footprint of the product system with respect to sustainable production and consumption, ii) to share stakeholders responsibility along the entire product life cycle, and iii) to avoid problem shifting between different life cycle stages.  相似文献   

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