现代汽车排放与控制技术ppt课件-第1章-双语

Automotive emission and controlBeijing University of Civil Engineering and ArchitectureChapter1:introduction2 Study Aims 学习目标学习目标：Understand the relation of automotive and environment Know about the pollution of main city in China Realize the disadvantage of automotive emission Study points 知识要点：知识要点：the environment and automotive the pollution of main city in China the disadvantage of CO,NOx,HC,PM,CO2 Example:3Read the examples in book.Would you like take an example about pollution?1.1 Air pollution and vehicles1.1.1 Air pollution Air pollution is the introduction of particulates,biological molecules,or other harmful materials into Earths atmosphere,causing diseases,death to humans,and damage to other living organisms.1.1.2 Sources There are various locations,activities or factors which are responsible for releasing pollutants into the atmosphere.These sources can be classified into two major categories.(1)Anthropogenic(man-made)sources:(2)Natural sources:1.2 Environmental impact the pollution in IranWhy？nFig 1.3 Word map of passenger cars per 1000 people Word map of passenger cars per 1000 peoplethe pollution of main city in ChinaWhat do you see from the table?1.3 Types of emissionsnEmissions that are principal pollutants of concern include CO,HC,NOx,PM and CO2Nitrogen oxides nNitrogen oxides(NOx)-Generated when nitrogen in the air reacts with oxygen at the high temperature and pressure inside the engine.nNOx is a precursor to smog and acid rain.nNOx is a mixture of NO,N2O,and NO2.NO2 is extremely reactive.It destroys resistance to respiratory infection.nNOx production is increased when an engine runs at its most efficient(i.e.hottest)part of the cycle.HydrocarbonsnHydrocarbons-A class of burned or partially burned fuel,hydrocarbons are toxins.nHydrocarbons are a major contributor to smog,which can be a major problem in urban areas.The formation of smogThe formation of smogHydrocarbonsnProlonged exposure to hydrocarbons contributes to asthma,liver disease,lung disease,and cancer.nRegulations governing hydrocarbons vary according to type of engine and jurisdiction;in some cases,non-methanehydrocarbons are regulated,while in other cases,total hydrocarbons are regulated.HydrocarbonsnTechnology for one application(to meet a non-methane hydrocarbon standard)may not be suitable for use in an application that has to meet a total hydrocarbon standard.nMethane is not directly toxic,but is more difficult to break down in a catalytic converter,so in effect a non-methane hydrocarbon regulation can be considered easier to meet.nSince methane is a greenhouse gas,interest is rising in how to eliminate emissions of it.HydrocarbonsCarbon monoxide nCarbon monoxide(CO)-A product of incomplete combustion,carbon monoxide reduces the bloods ability to carry oxygen;n overexposure(carbon monoxide poisoning)may be fatal.nCarbon Monoxide poisoning is a killer in high concentrations Particulate matternParticulate matter Soot or smoke made up of particles in the micrometre size range:Particulate matter causes negative health effects,including but not limited to respiratory disease and cancer.Volatile organic compounds(VOCs)nVolatile organic compounds(VOCs)-Organic compounds which typically have a boiling point less than or equal to 250 C;for example chlorofluorocarbons(CFCs)and formaldehyde.n Volatile organic compounds are a subsection of Hydrocarbons that are mentioned separately because of their dangers to public health.Carbon dioxide(CO2)Carbon dioxide is a greenhouse gas.Motor vehicle CO2 emissions are part of the anthropogenic contribution to the growth of CO2 concentrations in the atmosphere which is causing climate change.Sulfur oxidenSulfur oxide(SOx)-A general term for oxides of sulfur,which are emitted from motor vehicles burning fuel containing sulfur.Reducing the level of fuel sulfur reduces the level of Sulfur oxideemitted from the tailpipe.nEmissions of many air pollutants have been shown to have variety of negative effects on public health and the natural environment.1.4 Pollution Effects1.5 Emission factors1.6 Pollution reductionConclusionsnThe main factor of pollution automotive emission because of the city development,energy usage,and so on.nThe heavy pollution in China,and the North is heavier than the South.nAutomotive Emission includes many different contents,such as CO,HC,NOx,PM and CO2Thanks!Thanks!