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1.
随着全球能源消耗加剧,有限的石化燃料已难以满足人们对能源的需求;而汽车保有量却不断增加,使得车辆向大气中排出的有害污染物急剧增加,这对内燃机行业发展提出了新的要求和挑战。因此,各国从能源安全和环保的角度出发,开始寻找新型燃烧模式,实现内燃机的高效清洁燃烧。酯类含氧燃料作为石化燃料的替代品或添加剂,在燃烧过程中,可提供额外的氧,能使燃料进行充分燃烧,改善燃料物化性质,达到降低有害物质排放、提高燃烧性能的目的,故开发新型酯类含氧燃料有着环保和缓解对石化燃料依赖的双重意义。该研究对生物柴油、长链脂肪酸醚基酯、碳酸酯类、醚酯类、乙酰丙酸酯类清洁含氧燃料的理化性质、排放特性以及在内燃机上的应用进行了讨论,分析酯类含氧燃料的优缺点,并指出酯类含氧燃料应用趋势以及未来研究建议。 相似文献
2.
Air pollutants emissions from traffic are very closely connected to urban air quality, in a local scale, as well as to global
problems like climate change, in a large scale. Road transport air pollutants emissions represent, in most cases, a critical
parameter for a comprehensive and successful understanding of the mechanisms governing the air pollutants concentrations.
Hence, reliable estimations and comprehension of road transport emissions are indispensable in order to set reliable strategies
in the direction of air pollution abatement and management of air pollutants and greenhouse gases emissions. In this framework,
in the present work, the emissions of air pollutants from road transport in Greece will be presented for the whole period
1990–2009 as it was found that a detailed, accurate and reliable emissions inventory was missing. The whole period emissions
variation has clarified the impact of the change in the vehicle fleet, the engine technologies and the fuel quality. The calculated
results have revealed that the age of the vehicles and the corresponding engine technology are the critical parameters determining
the amount of the pollutants emitted. This was mainly observed in both passenger cars and heavy duty vehicles demonstrating
the importance of a renewal programme of the old circulating vehicles in order to set an effective air pollution abatement
strategy. Passenger cars were found to be responsible for the major part of most air pollutants emissions except from nitrogen
oxides and particulates emissions. Heavy duty vehicles contribute more than 66% to nitrogen oxides and particulates emissions.
For the whole time period, all calculated pollutants present a decreasing trend, with the exception of carbon dioxide and
nitrous oxide which increase constantly, ranging from −96% for sulphur dioxide to −1% for PM10. 相似文献
3.
Emberson L.D. Ashmore M.R. Murray F. Kuylenstierna J.C.I. Percy K.E. Izuta T. Zheng Y. Shimizu H. Sheu B.H. Liu C.P. Agrawal M. Wahid A. Abdel-Latif N.M. van Tienhoven M. de Bauer L.I. Domingos M. 《Water, air, and soil pollution》2001,130(1-4):107-118
The predicted increases in emissions of primary pollutants in many rapidly industrializing countries may have severe consequences for the health and productivity of forest trees and agricultural crops. This paper presents a review of air pollution impacts on vegetation in developing countries by summarising information describing the direct impacts to vegetation caused by a number of air pollutants (sulphur dioxide (SO2), nitrogen oxides (NOx), ozone (O3) and Suspended Particulate Matter (SPM)). This information has been collected by experts from a number of rapidly industrializing countries in Asia, Latin America and Africa and includes observations of visible injury in the field and the use of transect studies and controlled experimental investigations to ascribe damage to different pollutant concentrations. The ability to synthesise this information to define exposure-response relationships and subsequent air quality guidelines similar to those established in North America and Europe is assessed. In addition, the use of regional and global models describing pollution concentrations is discussed with reference to assessing the extent of adverse impacts and identifying regions likely to be most at risk from air pollution, both for the present day and in the future. The evidence summarised in the paper clearly shows that current pollutant concentrations experienced in many developing countries, particularly Asia, can result in severe damage to vegetation and that without appropriate control measures such damage is likely to worsen in the future as pollutant emissions increase. 相似文献
4.
P. Kågeson 《Water, air, and soil pollution》1995,85(1):225-236
We still have insufficient knowledge about the way that different types of vehicles are actually used (loads, driving behaviour etc.). This means that most statements on specific and aggregate emissions as well as on the cost-effectiveness of different measures should be judged with caution. There is still large scope for reducing emissions from transport by technical measures. This is particularly true for shipping, off-road vehicles and for most types of road vehicles. Improved maintenance and extended durability of emission control systems seem to be among the most cost-effective measures where road transport is concerned. The contribution from improved grades of diesel and petrol towards lower aggregate emissions of acidifying substances is likely to be small. Changing the modal split could be expected to be an expensive way of reducing air pollution from road transport except for regions suffering from congestion. 相似文献
5.
Major factors (emissions and meteorology) controlling pollution patterns in Moscow are discussed in the context of different types of urban land use. Nitrogen oxide pollution is one of the main air quality problems in the city. Power generation is the major source of nitrogen oxides: in 1994, it accounted for 63% of the total NOx emissions with transport contributing 30%. CO emissions are produced almost entirely by road transport. An increase in CO levels has been observed since 1990 in line with growing car ownership. Analyses of seasonal and diurnal variations in CO, NO and NO2 concentrations are presented. Meteorological conditions during an intense pollution episode are analysed in the context of the characteristics of the main sources of pollution. The occurrence of high levels of CO concentrations is associated with high pressure systems, surface-based inversions and low wind speeds. High concentrations of NO2 are caused by fumigation of the surface with pollutants emitted by power plants. The passage of warm weather fronts, the decay of elevated temperature inversions, and stronger winds are identified as meteorological condition leading to NO2 build-up. 相似文献
6.
A computer based system, Best Available Technology Evaluator (BATE), has been developed for the evaluating cost and performance of the best available technologies for removing volatile organic chemicals (VOCs) from drinking water. The treatment processes considered are air stripping tower (AST), and air stripping with off-gas control by gas phase granular activated carbon (GPGAC) and liquid phase granular activated carbon (LPGAC). BATE is unique in its ability to model multicomponents, optimise total cost for different process configurations and yield the best process design for a given VOC scenario. This paper, the first in a two-part series, highlights a new cost optimization method for the AST with GPGAC system and a technique for combining mathematical models for efficient process design of AST and GPGAC processes. Discussion of LPGAC simulation results and comparison of an LPGAC system with AST and GPGAC processes for a variety of VOC scenarios will follow in the next paper. 相似文献
7.
Most estimates of emission are concerned with the nation state level. This paper will discuss methods utilised in the estimates of emissions to the atmosphere of sulphur dioxide, volatile organic compounds and oxides of nitrogen from a densely populated and heavily industrialised region of the United Kingdom. Data on power generation, industrial plant, fuel usage, air, sea and road transportation, and human population statistics have been integrated into a method to provide regional emission estimates. The resulting emission patterns are described in terms of sources and emission density. Spatial and temporal patterns are identified and major sources of emissions discussed in terms of national control programmes. Transportation is the dominant source of oxides of nitrogen emissions whilst power generation is the dominant source of sulphur dioxide. The relative importance of the North West as an emission source within the UK is assessed. The change in the strengths of acidifying emissions between 1987 and 1992 is discussed and the rate of change in emission magnitudes between the North West region and the UK as a whole compared. 相似文献
8.
M. Johansson R. Suutari J. Bak G. Lövblad M. Posch D. Simpson J.-P. Tuovinen K. Tørseth 《Water, air, and soil pollution》2001,130(1-4):1739-1744
Impacts of air pollutants and especially acidification in ecosystems have been of serious concern in the Nordic countries since the 1970s. The current approach to assess several pollutants (sulfur and nitrogen oxides, ammonia, volatile organic compounds) and their effects (acidification, eutrophication and ground-level ozone) simultaneously is extremely complex. This study explored the relative role of nitrogen oxides in environmental impacts in the Nordic countries. The share of NOx in the exceedances of critical loads, the long-term ecosystem protection targets, was found to be roughly 25% in acidification and 50% in eutrophication. The contribution of NOx emissions to ground-level ozone formation was considered important, as NOx is the limiting precursor in ozone formation in the Nordic countries. The comparison of observed and modeled accumulated ozone concentrations (AOT40) for the early 1990s shows noticeable differences in the Nordic area, partly due to the sensitivity of the AOT40 indicator to the 40 ppb threshold value. 相似文献
9.
秸秆直燃发电供应链气体及颗粒污染物排放的生命周期评价 总被引：1，自引：1，他引：0
秸秆发电以其极好的环保效用和可再生能源利用引起各界关注,但是由于秸秆轻、薄、散的特性,导致在秸秆收集和运输的效率十分低下,从而会消耗大量石化燃料,排放出大量的气体及颗粒污染物,加之秸秆发电供应链的终端直燃发电也会排放一定污染物,必然会对其环保效用带来影响。该文依据生命周期评价方法,通过建立4个秸秆发电供应链场景,包含秸秆收集、打捆、运输存储、解包破碎以及最终发电等阶段,对其中机械及车辆石化燃料的消耗以及污染物的排放进行定量计算,发现4个秸秆发电供应链的污染物排放有较大差距,其中CO2相差1.2~2倍,CO相差1.4~5.4倍,NOX相差1.5~4.2倍,PM相差1.4~6.5倍。秸秆发电供应链环保效果与秸秆发电供应链中收集、预处理及运输存储模式有较大关系,预处理压缩环节、短距离农用车运输及压缩后道路运输距离是关键,这些因素的合理配置直接关系到秸秆发电供应链环保效用的高低。对秸秆发电供应链的整体排放以处理单位质量秸秆排放的污染气体和可吸入颗粒排放指数为标准,通过与秸秆露天燃烧和燃煤发电供应链对比分析,发现相对秸秆露天燃烧PM排放指数12.95 g/kg,秸秆发电供应链的PM排放指数为0.12 g/kg;相对燃煤发电供应链CO2排放指数1 010.1 g/kg,秸秆发电供应链的CO2排放指数为43.44 g/kg,在减少由露天焚烧秸秆造成的应急性雾霾天气和减少碳排放方面有积极作用。 相似文献
10.
Werner Bidlingmaier 《Compost science & utilization》2013,21(4):64-68
In recognition of the reaction that some odours generate, it is understandable that limits for emissions be established for composting plants, especially when there are residential areas nearby. This paper discusses results of an investigation into the environmental effects of odours from a composting facility. Emissions which are generated during delivery, treatment and composting can be avoided by using closed facilities and exhaust air collection systems, as well as by purification of exhaust air through methods such as biofilters. By using a qualified composting system, emissions can be reduced to an acceptable level. 相似文献
11.
Acid deposition: Perspectives in time and space 总被引：1，自引：0，他引：1
J. N. Galloway 《Water, air, and soil pollution》1995,85(1):15-24
Most acid-deposition investigations have been concerned with the impact of nitrogen oxides (NOx) and sulfur dioxide (SO2) emissions on Europe and North America. This paper examines three issues beyond this central focus. Major conclusions are 1) ammonia (NH3) emissions and subsequent nitrogen (N) accumulation in terrestrial ecosystems have the potential to generate significant acidification in terrestrial and aquatic ecosystems; 2) sulfur (S) and N accumulation in environmental reservoirs will not only result in significant and extensive acidification but will also impact the earth's radiation balance, tropospheric oxidizing capacity, ecosystem nutrient balance and groundwater quality; and 3) future emissions will substantially increase in the developing world, especially in Asia. By 2020, Asian emissions of SO2, NOx and NH3 will be equal to or greater than the combined emissions from Europe and North America. 相似文献
12.
H. M. ApSimon S. Couling D. Cowell R. F. Warren 《Water, air, and soil pollution》1995,85(4):1891-1896
European emissions of reduced nitrogen, arising principally from agriculture, are comparable with those of oxidised nitrogen from mobile and stationary combustion sources. It is therefore important to include ammonia emissions in working towards a new protocol on nitrogen under the programme of the UN Economic Commission for Europe on the control of transboundary air pollution. However the nature of the sources and the subsequent atmospheric transport and chemistry are very different from other acidifying pollutants. This paper describes work in hand under the MARACCAS project to compare agricultural activities in different European countries and to assess the applicability and efficacy of potential abatement measures. The aim is to derive abatement costs for each country relating successive emission reductions to the costs of achieving them, to be used by the UN ECE Task Force on Integrated Assessment Modelling (TFIAM) — in particular with our Abatement Strategies Assessment Model, ASAM. The paper will also address the large uncertainties involved in integrated assessment modelling with respect to ammonia, and suggest how these may be allowed for in deriving cost-effective abatement strategies. 相似文献
13.
K.-Y. Wang D.E. Shallcross P. Hadjinicolaou C. Giannakopoulos 《Water, air, and soil pollution》2004,156(1):29-55
Continuous ambient monitoring data of major air pollutants such as CO, NOx and NMHC (non-methane hydrocarbons) for the 1994–2001 period were analysed to establish the relationship between patterns of vehicular emitting species and vehicular emissions in the urban area of Taipei. These characteristics are consistent with measurements in London and Athens, indicating that vehicular emissions are a major contributing factor to air pollution in Taipei. Sensitivity studies relating ambient air pollution to vehicular emissions in the urban area of Taipei were performed and further examined by analysing some special events where the citys overall vehicle usage were at their extremes. Analysis of ambient measurements during the passing of Typhoon Nari shows very low levels of CO (0.3–0.4 ppmv), NOx (5–10 ppbv) and NMHC (0.01–0.05 ppmv), with no well-defined daily patterns. The measurements during Typhoon Nari were compared with measurements during the Chinese New Year and during Typhoon Herb. All analyses show distinctive low pollution periods surrounded by elevated trace gas concentrations, initiated by normal working practices. This revealed the severe impact of vehicle exhaust emissions on air pollution levels in Taipei City. Further impacts from vehicles were examined by comparing the post-Nari measurements with those before the arrival of the typhoon and comparing these data with a photochemical modelling system. It was found that as high as 15 ppmv of CO, 250 ppbv of NOx and 2.5 ppmv of NMHC were measured during the day time, with about a 50% increase in ambient vehicular pollutants in the first 2 days after the passing of Typhoon Nari. Implications for pollution related impacts on human health within Taipei are noted. 相似文献
14.
Streets David G. Tsai Nancy Y. Akimoto Hajime Oka Kaoru 《Water, air, and soil pollution》2001,130(1-4):187-192
Acid deposition is a serious problem throughout much of Asia. Emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) have been increasing steadily, as nations strive to increase their levels of economic development. Coal and fuel oil have been the main choices for powering industrial development; and, until recently, only a few countries had taken steps to avert the atmospheric emissions that accompany fuel combustion. This paper discusses trends in emissions of SO2 and NOx that have occurred in Asian countries in the period 1985–1997, using results from the RAINS-Asia computer model and energy-use trends from the IEA Energy Statistics and Balances database. Emissions of SO2 in Asia grew from 26.6 Tg in 1985 to 33.7 Tg in 1990 and 39.2 Tg in 1997. Though SO2 emissions used to grow as fast as fossil-fuel use, recent limitations on the sulfur content of coal and oil have slowed the growth. The annual-average emissions growth between 1990 and 1997 was only 2.2%, considerably less than the economic growth rate. Emissions of NOx, on the other hand, continue to grow rapidly, from 14.1 Tg in 1985 to 18.7 Tg in 1990 and 28.5 Tg in 1997 (6.2% per year between 1990 and 1997), with no signs of abating. Thus, though SO2 remains the major contributor to acidifying emissions in Asia, the role of NOx will become more and more important in the future. 相似文献
15.
Spark ignition engines in today's automobiles and trucks are a major source of urban air pollution. The engine exhaust is the source of NO, NO2, and CO emissions. The exhaust, fuel tank and carburetor are the sources of unburned hydrocarbons. Almost 20% of the total distance travelled by automobiles consist of short trips from the starting point. In most cases, engine and driveline temperature will remain well below optimum levels in this period. Therefore in these cases, cold starting effects will influence the vehicle for a large proportion of driving time. The problem is enhanced in seasons of cold weather and high ambient humidity. Preheating the engine prior to cold starting has been reported as a good way to avoid many of these undesired effects. In the present study, CO emissions, rpm and water, oil, air and exhaust gases temperatures were determined in experiments of cold starting with and without preheating intake air of the engine. Results showed an important decrease in CO emissions and a good general performance of the engine when intake air was preheated. 相似文献
16.
Danilo Santini 《Water, air, and soil pollution》1975,5(2):185-194
The paper examines water use in industrial production as a cause of geographical clustering of major air polluting industries. It shows that the majority of particulate and sulfur oxide emissions in the State of Illinois is emitted by industries using more than five billion liters of water per establishment per year. It also shows that the majority of industrial air pollutants is emitted within urban areas which are on water bodies with high and consistent volumes of water available. These and other results cited in the paper imply that any policy directly or indirectly promoting geographic dispersal as a means of reducing air pollution concentrations and population exposure rates is likely to be limited in effectiveness. It is suggested that such a policy can be effective only if at least one of two specified conditions is met. However, these conditions do not, by themselves, insure the success of such a policy. Finally, it is observed that the conjunction of air pollution with industrial water use indicates that much closer attention is needed to the relationship between air pollution and water pollution policies. 相似文献
17.
Chad Shouquan Cheng Monica Campbell Qian Li Guilong Li Heather Auld Nancy Day David Pengelly Sarah Gingrich David Yap 《Water, air, and soil pollution》2007,182(1-4):117-130
Using within-weather-group air pollution prediction models developed in Part I of this research, this study estimates future air pollution levels for a variety of pollutants (specifically, carbon monoxide – CO, nitrogen dioxide – NO2, ozone – O3, sulphur dioxide – SO2, and suspended particles – SP) under future climate scenarios for four cities in south-central Canada. A statistical downscaling method was used to downscale five general circulation model (GCM) scenarios to selected weather stations. Downscaled GCM scenarios were used to compare respective characteristics of the weather groups developed in Part I; discriminant function analysis was used to allocate future days from two windows of time (2040–2059 and 2070–2089) into one of four weather groups. In Part I, the four weather groups were characterised as hot, cold, air pollution-related, and other (defined as relatively good air quality and comfortable weather conditions). In estimating future daily air pollution concentrations, three future pollutant emission scenarios were considered: Scenario I – emissions decreasing 20% by 2050, Scenario II – future emissions remaining at the same level as at the end of the twentieth century, and Scenario III – emissions increasing 20% by 2050. The results showed that, due to increased temperatures, the average annual number of days with high O3 levels in the four selected cities could increase by more than 40–100% by the 2050s and 70–200% by the 2080s (from the current areal average of 8 days) under the three pollutant emission scenarios. The corresponding number of low O3 days could decrease by 4–10% and 5–15% (from the current areal average of 312 days). For the rest of the pollutants, future air pollution levels will depend on future pollutant emission levels. Under emission Scenarios II and III, the average annual number of high pollution days could increase 20–40% and 80–180%, respectively, by the middle and late part of this century. In contrast, under Scenario I, the average annual number of high pollution days could decrease by 10–65%. 相似文献
18.
氨气是大气中唯一的碱性气体,减少氨排放对控制大气雾霾有重要作用,畜禽养殖业是重要的氨气排放源,科学评估不同环节的氨气排放量及减排潜力具有重要意义。本文根据文献资料总结了国内外不同畜禽养殖舍的氨排放因子情况、主要减排技术及效率,并结合第二次全国污染源普查获得的全国主要畜禽采用机械通风养殖场的数量和养殖量,对中国分地区、分畜种密闭式畜舍外排空气的氨减排潜力进行了分析。结果表明：中国机械通风畜舍外排空气氨气年减排潜力为26.56万t,主要来自生猪、蛋鸡和肉鸡三种畜禽,其减排潜力分别为10.18万t、7.73万t和6.75万t,三种畜禽舍减排潜力占比92.8%;从地区上看,主要可实施地区为华东区、中南区和华北区,氨气减排潜力分别占全国的35.1%、26.9%和14.9%。建议开展密闭式生猪、蛋鸡和肉鸡舍氨减排设施建设,可为全国氨减排和大气环境质量改善提供保障。 相似文献
19.
氮循环是地球圈层中水-土-气-生多介质、多界面的复杂过程，与土壤健康、粮食安全、全球变暖、空气污染、水体质量等环境问题密切相关。近年来，得益于计算机技术的快速发展和海量、多源数据的产生，机器学习迅速成为研究氮素循环强有力的工具。本文系统梳理了机器学习的功能性概念，包括典型开发流程和学习应用场景等；总结了机器学习的典型应用算法，包括经典机器学习（如随机森林、支持向量机等）和深度学习（如卷积神经网络、长短期记忆网络等）；并综述了机器学习在氮循环研究领域的应用研究进展，包括大气、水体、土壤和植物/作物等介质的氮素代谢机制、模拟氮素循环过程及管理氮素流动等。未来基于大数据和机器学习技术的特征工程和模型融合的研究，将会给氮循环领域的数据分析与建模带来巨大变革。同时，将机器学习与基于物理过程的模型相结合解决氮循环过程中的复杂问题，可为服务国家“双碳”战略以及控制全球变暖、空气污染等环境问题提供重要支撑。 相似文献