Particulate air pollution matter

Petroleum refineries are a somce of hazardous and toxic air pollutants, such as BTEX compounds (benzene, toluene, ethylbenzene, and xylene). They are also a major source of criteria air pollutants particulate matter (PM), nitrogen oxides (NO t), carbon monoxide (CO), hydrogen sulfide (H2S), and sulfur oxides (SO ). 

WHO global air quality guidelines are available for the following air pollutants particulate matter, ozone, nitrogen dioxide, and sulfur dioxide. The latest revision, which was published in 2005, substantially lowered the recommended limits of particulate matter, ozone, and sulfur dioxide. The publication is available via the WHO Regional Office for Europe s Web site (WHO 2007b). 

One of the most successful applications of PIXE has been in the analysis of air pollution particulate matter. Atmospheric particulate matter is typically collected by impaction on a filter paper, which provides an ideal thin sample for PIXE analysis. Another aspect of PIXE that is very important for the analysis of aerosol samples is the ability to analyze a large number of samples in a short time. PIXE analyses typically take less than a minute, and the entire irradiation, counting, sample changing, and analysis procedure can be automated. 

The highest priority threats in this area include nanoparticles capable of destroying brain tissue or cells through inhalation or ingestion in food or water supplies. Studies of air pollution, particulate matter, and nanoparticle toxicology have lead to the development of a framework related to the potential consequences of inhalation exposure of nanoparticles, including lung inflammation and cardiovascular injury... 

Kryzanowski M, WHO European Centre for Environment and Health B, Germany (2007) Exposure of children to air pollution (particulate matter) in outdoor air. Fact sheet 33 Kubilay N, Saydam A, Yemenicioglu S et al (1997) Seasonal chemical and mineralogical variability of atmospheric particles in the coastal region of the Northeast Mediterranean. Catena 28 313-328... 

In the USA, the Clean Air Act of 1970 established air-quality standards for six major pollutants particulate matter, sulfur oxides, carbon monoxide, nitrogen oxides, hydrocarbons, and photochemical oxidants. It also set standards for automobile emissions - the major source of carbon monoxide, hydrocarbons, and nitrogen oxides. An overview of the major standards is given in Tab. 10.2. The levels of, for example, the European Union (1996) are easily achieved with the present catalysts. The more challenging standards, up to those for the ultralow emission vehicle, are within reach, but zero-emission will probably only be attainable for a hydrogen-powered vehicle. 

Conventional power plants can pollute the air with particulate matter and the oxides of sulfur, nitrogen, and carbon, causing acid rain and other problems. However, with proper scrubbing and filtering at the source, this pollution has been greatly reduced. 

Sulfur oxides, in the form of sulfur dioxide (SO-) sulfur trioxide (SO-), sulfuric acid (H-SO ) and sulfates (SO ). Most of these pollutants are emitted to the atmosphere as sulfur dioxide, which is chemically converted by oxidation to SO- and sulfates in the air. Both particulate matter from smoke and sulfur oxides are known to be components in the smogs of London. They are mainly the result of combustion of coal. 

At local and urban levels, it is essentially a question of vicinity pollution. Several air pollutants are concerned sulphur dioxide, SO2 (primary pollutant) nitrogen oxides NO (primary or secondary pollutants) particulate matter PM (primary and secondary pollutants) carbon monoxide, CO, (primary pollutant) (volatile) organic compounds, HC (or VOCs) (primary and secondary pollutants), and photochemical oxidants, O3, PAN (secondary pollutants). Organic compounds account for a wide range of hydrocarbons and are found in solid, liquid, and gas forms. 

Air pollution, and especially particulate matter, must be managed for health and environmental reasons. Studying and monitoring the chemical composition and size distributions of particulate matter can help us understand the dynamics of air pollution. Particulate pollution can damage sensitive ecosystems by... 

As discussed in Section 6.5, water vapor and the heat released and absorbed by transitions of water between the vapor state and the liquid or solid state are strongly involved in atmospheric energy transfer. Condensed water vapor in the form of very small droplets is of considerable concern in atmospheric chemistry. The harmful effects of some air pollutants—for instance, the corrosion of metals by acid-forming gases—requires the presence of water, which may come from the atmosphere. Atmospheric water vapor has an important influence on pollution-induced fog formation under some circumstances. Water vapor interacting with pollutant particulate matter in the atmosphere may reduce visibility to undesirable levels through the formation of very small atmospheric aerosol particles. 

In the United States, particulate matter is a term that has found wide usage as a result of legislated requirements under the Clean Air Act (CAA 22). The CAA requires the US Environmental Protection Agency (EPA) to list pollutants that may reasonably be anticipated to endanger public health or welfare and to issue air quality criteria for them hence, the term criteria pollutants. Particulate matter is identified as a criteria pollutant for which the EPA will develop criteria and establish National Ambient Air Quality Standards (NAAQS), as will be discussed in detail later. 

E. Bakke, "The AppHcation of Wet Electrostatic Precipitators for Control of Eiue Particulate Matter," Preprint, Symposium on Control of Tine Particulate Emissions from Industrial Sources, Joint U.S.-USSR Working Group, Stationay Source Air Pollution ControlTechnology, San Francisco, Calif, Jan. 15—18, 1974. 

E. A. Wolfe, Gas Flow Rate and Particulate Matter Determination of Gaseous Effluents, Bay Area Air Pollution Control District 1480, San Erancisco, Calif., 1961. 

Pollutant Formation and Control in Flames Key combustion-generated air pollutants include nitrogen oxides (NOJ, sulfur oxides (principally SO9), particulate matter, carbon monoxide, and unburned hydrocarbons. 

Dust storms that entrain large amounts of particulate matter are a common natural source of air pollution in many parts of the world. Even a relatively small dust storm can result in suspended particulate matter read-... 

Static sampling systems are defined as those that do not have an active air-moving component, such as the pump, to pull a sample to the collection medium. This type of sampling system has been used for over 100 years. Examples include the lead peroxide candle used to detect the presence of SO2 in the atmosphere and the dust-fall bucket and trays or slides coated with a viscous material used to detect particulate matter. This type of system suffers from inability to quantify the amount of pollutant present over a short period of time, i.e., less than 1 week. The potentially desirable characteristics of a static sampling system have led to further developments in this type of technology to provide quantitative information on pollutant concentrations over a fked period of time. Static sampling systems have been developed for use in the occupational environment and are also used to measure the exposure levels in the general community, e.g., radon gas in residences. 

The three major characteristics of particulate pollutants in the ambient atmosphere are total mass concentration, size distribution, and chemical composition. In the United States, the PM q concentration, particulate matter with an aerodynamic diameter <10 /nm, is the quantity measured for an air quality standard to protect human health from effects caused by inhalation of suspended particulate matter. As shown in Chapter 7, the size distribution of particulate pollutants is very important in understanding... 

Fig. 14-6. Schematic diagram of a four-stage cascade impactor. Source Giever, P. M., Particulate matter sampling and sizing, in "Air Pollution," 3rd ed., Vol. lil (A. C. Stem, ed.). Academic Press, New York, 1976, p. 41,...

Figure 15-1 shows the Los Angeles, California, basin stationary air monitoring network, one of the most extensive in the United States (6). At most of these locations, automated instruments collect air quality data continuously. Five pollutant gases are monitored, and particulate matter filter samples are collected periodically. 

For any pollutant, air quality criteria may refer to different types of effects. For example. Tables 22-1 through 22-6 list effects on humans, animals, vegetation, materials, and the atmosphere caused by various exposures to sulfur dioxide, particulate matter, nitrogen dioxide, carbon monoxide, ozone, and lead. These data are from fhe Air Quality Criteria for these pollutants published by the U.S. Environmental Protection Agency. 

The concentration of indoor pollutants is a function of removal processes such as dilution, filtration, and destruction. Dilution is a function of the air exchange rate and the ambient air quality. Gases and particulate matter may also be removed from indoor air by deposition on surfaces. Filtration systems are part of many ventilahon systems. As air is circulated by the air-conditioning system it passes through a filter which can remove some of the particulate matter. The removal efficiency depends on particle size. In addition, some reactive gases like NOj and SOj are readily adsorbed on interior surfaces of a building or home. 

In the past, for many air pollution control situations, a change to a less polluting fuel offered the ideal solution to the problem. If a power plant was emitting large quantities of SO2 and fly ash, conversion to natural gas was cheaper than instaUing the necessary control equipment to reduce the pollutant emissions to the permitted values. If the drier at an asphalt plant was emitting 350 mg of particulate matter per standard cubic meter of effluent when fired with heavy oil of 4% ash, it was probable that a switch to either oil of a lower ash content or natural gas would allow the operation to meet an emission standard of 250 mg per standard cubic meter. 

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