采用不同后处理装置的柴油机减排效果分析

对分别安装DOC+ DPF和DOC+ POC后处理装置的两台柴油机进行了排放试验.在有/无后处理装置两种状态下,通过ESC试验对两台发动机常规污染物CO、HC、NOx和PM以及非常规污染物NO2和SO2的排放水平进行检测和对比分析,此外对全负荷烟度水平也进行了检测.试验结果表明:DOC+ DPF后处理装置对常规污染物的...     

机动车国五排放标准拟发布首提大幅削减颗粒物

研究表明,2011年轻型汽车排放氮氧化物(NOx)80.7万吨、颗粒物(PM)6.5万吨、碳氢化合物(HC)166.2万吨、一氧化碳(CO)1621.7万吨,已成为北京等城市空气污染物的主要来源.     

广西主要农作物秸秆露天焚烧污染物排放分析

通过建立模型,估算广西主要农作物秸秆理论资源量、可利用秸秆资源量、秸秆露天焚烧量及秸秆露天焚烧污染物排放清单,分析广西主要农作物秸秆露天焚烧污染物排放情况。研究结果表明,秸秆露天焚烧的CO、CO2、NOx、SO2、CxHy、PM2.5年排放量分别为1073053.092t、13935400.960t、52121.666t、2177.406t、38785.052t、128875.241t。稻草和甘蔗秸秆是污染物排放的主要来源,贡献率最大,露天焚烧对空气质量影响呈现出季节性变化趋势。     

实施大气污染物排放总量控制后能源系统的减排效果

要以上海为例,采用MARKAL模型研究了能源系统对未来环境政策的响应。政策情景包括提高能源效率、能源结构调整、实施SO2排放总量控制等。研究结果显示,提高能源效率和实施能源结构调整后,上海市CO2、SO2和PM10排放量将明显降低。进一步削减NOx和PM10排放将主要取决于末端处理技术。     

实施大气污染物排放总是控制后能源系统的减排效果

以上海为例，采用MARKAL模型研究了能源系统对未来环境政策的响应。政策情景包括提高能源效率、能源结构调整、实施SO2排放总量控制等。研究结果显示，提高能源效率和实施能源结构调整后，上海市CO2、SO2和PM10排放量将明显降低。进一步削减NOx和PM10排放将主要取决于末端处理技术。     

生物质成型燃料锅炉燃烧节能减排效益分析

生物质成型燃料是重要的可再生能源,为准确研究其替代化石能源的节能减排效益,分析了生物质成型燃料的特性,并采用发热量比较法、物料衡算法、产排污系数法分别计算分析了生物质成型燃料锅炉燃烧的节能效益、CO2减排效益、废气污染物减排效益。结果表明:生物质成型燃料锅炉燃烧具有显著的节能减排效益,预计2020年,生物质成型燃料替代煤炭折合1579.5万tce,减少CO2排放4011.93万t,减少SO2排放30.99万t,减少NOx排放4.06万t,减少PM排放175.29万t。     

EGR/EGC技术结合系统降低柴油机排放的研究

对柴油机的排放尾气NOx，CO，HC和PM等进行全面分析，探索设计了一套由EGR（废气再循环技术）和EGC（发动机机外废气净化技术）结合的系统，EGR技术可以有效降低NOx的排放，机外废气净化技术技术可以在有效除去PM的同时降低HC，CO的排放，该系统能在较宽的转速和负荷范围内有效降低废气排放，解决同时降低NOx与PM排放的矛盾，废气排放全面降低。     

京津冀地区农村煤改气现状及减排潜力分析

对京津冀农村地区煤改气现状进行研究,并对当前采用的经济环境效益评价方法加以归纳,以近年来颁布的国家及地方政策为辅助依据估算农村燃煤减排潜力。根据计算结果,对比SO2、NOx、CO、PM10、PM2.5在三地区的减排效果得出,北京减排效果最明显,天津及河北省有明显改善;由减排分布得到,SO2、NOx、CO、PM10、PM2.5在北京市、天津市、河北省减排潜力分布中各占3%、1%、85%、6%和5%。由此看出,通过减少农村散煤使用来控制污染物排放量的方法具有良好的发展前景。然后进一步剖析当前出现的问题,以努力推进农村减排工作。     

台架中冷气管长度对发动机排放影响的研究

为研究发动机台架中冷器出气口与发动机进气口之间的连接管(简称中冷气管)长度对发动机排放的影响,采用国家标准GB17691-2018 《重型柴油车污染物排放限值及测量方法(中国第六阶段)》规定的世界统一瞬态测试循环(World harmonized transient cycle,WHTC)进行相关试验研究。以整车中冷气管为基准,设计了2种发动机台架排放试验方案。第1种方案中冷气管长度大于整车中冷气管长度,第2种方案中冷气管长度等同于整车中冷气管。试验结果表明:2种试验方案的一氧化碳(CO)、氮氧化物(NO_x)、碳氢化合物(HC)气态污染物测量结果相差不大:CO的偏差为1. 14%、NOx的偏差为2. 21%,HC的偏差为2. 61%;第2种方案的颗粒物(PM)比第1种方案的PM降低了67%左右。这表明台架中冷气管长度对发动机CO、NO_x、HC气态污染物排放几乎没有影响,但对PM排放影响较大。     

改善DMCC发动机废气排放质量的研究

为找到全面降低柴油机排放的途径,研究了加装氧化催化转化器对柴油／甲醇组合燃烧（DMCC）发动机排放特性的影响,比较了不同工作模式下各污染物的排放量。试验结果表明,DMCC模式下NOx和碳烟排放下降幅度较大,但HC和CO排放增加较多,微粒比排放量也有所增加。经过氧化催化后,HC和CO得到了较大程度的降低,微粒（PM）经氧化后比原机也有所下降。DMCC经采用催化转化器后,废气质量得到改善,实现了同时降低柴油机的NOx和PM的目的。     

铁基载氧体的污泥化学链气化过程中氮迁移热力学模拟与实验研究

基于吉布斯自由能最小化原理,采用HSC Chemistry 6.0软件,对污泥化学链气化过程中NO_x前驱物（NH₃和HCN）与Fe₂O₃载氧体的氧化还原行为进行了热力学模拟。基于污泥热解实验中NO_x前驱物的含量,计算载氧体与污泥的摩尔比（OC/SS）对NH₃、HCN以及NH₃和HCN混合气氧化过程的影响。热力学模拟结果表明：Fe₂O₃能显著促进NO_x前驱物的氧化和裂解,主要生成N₂,几乎无NO_x生成;当NH₃、HCN以及混合气（NH₃和HCN）分别作为还原剂时,其最优OC/SS分别为0.02、0.04和0.05;由于HCN还原性强于NH₃,其氧化速率较快。基于Fe₂O₃/Al₂O₃混合物（FeAl）载氧体,实验对比了污泥化学链气化与污泥热解过程中NO_x前驱物的释放特性,发现Fe₂O₃能显著降低烟气中NO_x前驱物的产率,NH₃和HCN产率分别下降32%和62%。实验结果与热力学模拟结果一致。     

Energy-related emissions and mitigation opportunities from the household sector in Delhi

Urban centers are the major consumers of energy, which is a major source of air pollution. Therefore, an insight into energy consumption and quantification of emissions from urban areas are extremely important for identifying impacts and finding solution to air pollution in urban centers. This paper applies the Long-range Energy Alternatives Planning (LEAP) system for modeling the total energy consumption and associated emissions from the household sector of Delhi. Energy consumption under different sets of policy and technology options are analyzed for a time span of 2001–2021 and emissions of carbon dioxide (CO₂), carbon monoxide (CO), methane (CH₄), non-methane volatile organic compounds (NMVOCs), nitrogen oxides (NO_x), nitrous oxide (N₂O), total suspended particulates (TSP) and sulfur dioxide (SO₂) are estimated. Different scenarios are generated to examine the level of pollution reduction achievable by application of various options. The business as usual (BAU) scenario is developed considering the time series trends of energy use in Delhi households. The fuel substitution (FS) scenario analyzes policies having potential to impact fuel switching and their implications towards reducing emissions. The energy conservation (EC) scenario focuses on efficiency improvement technologies and policies for energy-intensity reduction. An integrated (INT) scenario is also generated to assess the cumulative impact of the two alternate scenarios on energy consumption and direct emissions from household sectors of Delhi. Maximum reduction in energy consumption in households of Delhi is observed in the EC scenario, whereas, the FS scenario seems to be a viable option if the emission loadings are to be reduced.     

Policies to reduce energy use and environmental emissions in the transport sector : A case of Delhi city

This paper aims to analyze factors influencing energy consumption pattern and emission levels in the transport sector of Delhi, and extrapolates total energy demand and the vehicular emissions, using a computer-based software called ‘Long Range Energy Alternative Planning’ (LEAP) and the associated ‘Environmental Database (EDB)’. The study is restricted to passenger modes of transport in Delhi and does not include the freight model. Travel demand is first estimated by analyzing data on vehicle population, average distance travelled, and occupancy level. Next, data on travel demand, proportion of travel demand catered by road and rail, modal split, occupancy and fuel efficiency are compiled within the LEAP framework, in order to estimate the energy demand in Delhi. In addition, emission factors are compiled under EDB module of the LEAP structure to estimate the resultant pollution loading. The LEAP model is run under five alternative scenarios to estimate the current consumption of gasoline and diesel oil in Delhi and forecast the same for the years 1994/1995, 2000/2001, 2004/2005 and 2009/2010, respectively. Under each scenario, the model also estimates emissions of CO, HC, NO_x, SO₂, Pb and TSP. The total emissions are translated into concentration levels attributable to the passenger transport to get an indication of air quality in Delhi. This is accomplished by the use of proportional air quality model. Finally, scenario results are analyzed to study the impact of different urban transport policy initiatives that will reduce the growth of fuel demand and emissions. The prime objective is to arrive at an optimal transport policy that limits the future growth of fuel consumption as well as air pollution.     

连续蓄热式生物质气化/燃烧供热系统

生物质能源是一种环境友好的可再生能源,但也存在能量密度低、含水率高、碱金属含量高等缺点,导致其在热利用的过程中存在易结渣、堵灰及腐蚀、热效率不高等问题。本文结合生物质气化、炉内碱金属/硫固定、两级焦油裂解、蓄热式燃烧,以及冷凝热回收等多项先进技术,设计并搭建了连续蓄热式生物质气化/燃烧供热系统。以海洋贝壳类废弃物作为生物质成型燃料的添加剂和生物质焦油裂解过程的催化剂,在实现海洋废弃资源高值化利用的同时,克服了生物质热利用过程中的多项障碍,能够显著提高生物质能热利用效率,同时大幅度降低当前工业及民用供热过程中CO₂、SO_x、NO_x及烟尘的排放,具有良好的经济性与环保性。     

MILD条件下氢-天然气混合燃烧特性及排放物分析

针对目前天然气掺氢后燃烧效率及氮氧化物排放研究较少的问题,应用组分输运模型、涡耗散概念燃烧模型和Do辐射模型,结合GRI-22化学反应机理,建立柔和燃烧模拟模型,通过与实验结果对比验证了模型的可靠性,进一步应用该模型分析不同掺氢比例对燃烧特性的影响。结果表明,随着掺氢比例增加,燃料与氧化剂的混合程度逐渐提高,混合气体的径向分量不断减小;由于反应速率和放热速率提高,燃烧器内部的温度升高,热力型氮氧化物含量增高,主要集中于燃烧器后端;燃料进口速度增大会导致燃烧器内燃烧不完全、出口处温度降低,氧气浓度升高,氮氧化物含量降低。研究发现,天然气中掺入氢气更有利于达到柔和燃烧条件。     

Does environmental infrastructure investment contribute to emissions reduction? A case of China

Environmental infrastructure investment (EII) is an important environmental policy instrument on responding to greenhouse gas (GHG) emission and air pollution. This paper employs an improved stochastic impact by regression on population, affluence and technology (STRIPAT) model by using panel data from 30 Chinese provinces and municipalities for the period of 2003–2015 to investigate the effect of EII on CO₂ emissions, SO₂ emissions, and PM_2.5 pollution. The results indicate that EII has a positive and significant effect on mitigating CO₂ emission. However, the effect of EII on SO₂ emission fluctuated although it still contributes to the reduction of PM_2.5 pollution through technology innovations. Energy intensity has the largest impact on GHG emissions and air pollution, followed by GDP per capita and industrial structure. In addition, the effect of EII on environmental issues varies in different regions. Such findings suggest that policies on EII should be region-specific so that more appropriate mitigation policies can be raised by considering the local realities.     

Hydrogen as a fuel for the transportation sector: possibilities and views for future applications in Libya

World-wide energy consumption in the transportation sector accounts for about one quarter of the total energy consumption. This implies that thousands of tons of pollutants are emitted each year. The total pollutants include CO, CO₂, HC, NO_x, SO₂ and soot particles. In Libya, the transportation sector counts for a big share of the total energy demand. So if this sector would be changed to clean fuel,the pollution will be reduced dramatically. Hydrogen is proposed (hypothetically) to be used for the transportation sector in Libya. This paper will review the advancement of this technology world wide, in a sense of hydrogen production, storage, transportation and refueling systems. The possibilities of using hydrogen in the transportation sector in Libya and the expected advantages, obstacles and constraints associated with its application and public acceptance.     

Electrification of the Canadian road transportation sector: A 2050 outlook with TIMES-Canada

We use a newly developed bottom-up model of the entire Canadian energy system (TIMES-Canada) to assess potentials for electrification of the road transport sector. A special emphasis has been put on the modelling of the Canadian road transport, by considering a variety of vehicles for passenger and freight transportation. Besides a business-as-usual (baseline) scenario, we have analysed an energy policy scenario imposing targets for electric vehicle penetration and a climate policy scenario imposing targets for greenhouse gas emission reduction. Our analysis shows on the one hand that electric vehicles penetrate notably the passenger vehicle market after 2040 in the baseline scenario and after 2030 in the energy policy scenario (following the assumed penetration targets). On the other hand, the assumed climate policy forces a stronger penetration of electric vehicles for passenger transportation, with a progressive phasing out of internal combustion engine vehicles, whereas the latter vehicles remain dominant for freight transportation but with a shift away of fossil fuels and in favour of biofuels. A sensitivity analysis on the (assumed) evolution of electric vehicles over time confirms these general trends.     

Integrated energy planning for transportation sector—A case study for Iran with techno-economic approach

Transportation sectors in developing countries suffer from some diseases that one of them is ever-increasing energy consumption. Integrated National Energy Planning (INEP) in transportation sector is a solution for these countries to alter their suboptimal pattern and rationalize their energy consumption. One of the INEP targets is determining optimal patterns of fuels and transportation technologies to satisfy future demand of freight and passenger transportation at the lowest cost levels. Following the above target, this paper is concerned with the optimal consumption pattern of fuels focusing on vehicle technologies within the next 25 years (up to 2029). Using Energy Flow Optimization Model-ENVironment (EFOM-ENV) model, various steps as designing of “Reference Energy System (RES)” of the model, data processing and scenario analysis are followed. Based on the modeling results, substitution of urban railroad technologies (subway, LRT and monorail), all of passenger CNG technologies (cars, buses and minibuses), rural railroad freight technologies (electrical, gas oil and LNG freight trains) and finally, CNG and LNG heavy and light trucks with current passenger and freight vehicle technologies are suggested. This scenario will decline fuel consumption by about 14% totally, that the most part of it belongs to gasoline and gas oil (24% and 17%, respectively). Total discounted cost of transportation system will decline from 806.20 to 691.74 billion dollars (14%) during the time horizon.     

Al2O3/SiOxNy/SiNx叠层钝化膜对PERC太阳电池性能及LID效应的研究

由于等离子体增强化学的气相沉积（PECVD）法制备的SiO_xN_y薄膜中含有大量H原子,因而具有优异的表面钝化性能。通过在PERC太阳电池的Al₂O₃/SiN_x背钝化叠层中间插入一层SiO_xN_y薄膜,形成Al₂O₃/SiO_xN_y/SiN_x结构,可避免SiN_x所带的固定正电荷对Al₂O₃负电荷场钝化效应的负面影响。试验结果表明,硅片少子寿命从原来的130 μs提高至162 μs,电池转换效率增加0.09%。同时,基于Al₂O₃/SiO_xN_y/SiN_x背钝化的PERC太阳电池的LID也得到了改善,由对照组的1.83%下降到实验组的1.09%。