Sources of Atmospheric Pollution

As noted above, one of the major problems with atmospheric emissions is the number of potential sources. Solid emissions arise from  

Vapor emissions are even more difficult as they have even more sources such as  

In larger plants, significant reductions in VOC emissions can usually be made by controlling major sources, such as tank venting, condensers and purges, and by inspection and maintenance of gaskets and shaft seals. 

The largest volume of atmospheric emissions from process plants occurs from combustion producing gaseous emissions. Such emissions are created from  

In addition to the gaseous emissions from the combustion of fuel, gaseous emissions are also produced by chemical production, for example, SO, from sulfuric acid production, NO from nitric acid production, HC1 from chlorination reactions, and so on. 

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To these technological constraints are added an increasing preoccupation with limiting the evaporation losses that are an important source of atmospheric pollution (Me Arragher et al., 1990). 

Table I. Sources of Atmospheric Pollution in 1989 (metric tons per year)...

The wavelength-dispersive x-ray spectroscopy method (ASTM D6376) provides a rapid means of measuring metallic elements in coke and provides a guide for determining conformance to material specifications. A benefit of this method is that the sulfur content can also be used to evaluate potential formation of sulfur oxides, a source of atmospheric pollution. This test method specifically determines sodium, aluminum, silicon, sulfur, calcium, titanium, vanadium, manganese, iron, and nickel. 

The most significant sources of atmospheric pollutants in Europe in 1999... 

Interest in trace element emissions received impetus from published reports of widespread atmospheric dissemination of these substances (1), especially mercury (2, 3), as a consequence of fossil fuel use. More current information indicates that the original mercury discharge estimates were overstated, since they were based on nonrepresentative, ore-associated coal samples (4). Of the fossil fuels, coal is considered the major source of atmospheric pollution (5) and, compared with oil and... 

Abstract Gaseous and particulate emissions from vehicles represent a major source of atmospheric pollution in cities. Recent research shows evidence of, along with the primary emissions from motor exhaust, important contributions from secondary (due to traffic-related organic/inorganic gaseous precursors) and primary particles due to wear and resuspension processes. Besides new and more effective (for NO emissions) technologies, non-technological measures from local authorities are needed to improve urban air quality in Europe. 

Combustion systems are major sources of atmospheric pollutants. The oxidation of a hydrocarbon fuel proceeds rapidly (within a few milliseconds) and adiabatically to establish equilibrium among the H/C/O species (CO2, H2O, O2, CO, H, OH, O, etc.) at temperatures that often exceed 2000 K. At such high temperatures, the highly endothermic oxidation of N2 ... 

In addition to being removed from the atmosphere by physical processes, atmospheric chemicals can be removed by chemical transformations. Chemical transformations also can be sources of atmospheric pollutants a notorious example is the production of urban smog by reactions involving hydrocarbons, nitrogen oxides, and oxygen. 

The main source of atmospheric pollution is the industrial use of PCB technical mixtures obtained by FeC -catalyzed chlorination of biphenyl. Thermal... 

After analyzing the data on the chemical composition of the atmospheric precipitation measured over the territory of Tashkent city and Tashkent province, it was found that the local sources of atmospheric pollution have a certain effect on the chemical composition of precipitation (Figure 11). 

In this section we describe the methodology used to study the effect of emissions from the local sources of atmospheric pollution on the processes of secondary aerosol formation. The basic admixtures selected as the main objects of investigations were dust and oxides of sulphur and nitrogen which are the main components of die emissions from the industrial... 

Hashimoto Y, Hwang JT, Yanagisawa S. 1970. Possible source of atmospheric pollution of selenium. Environ Sci Technol 4 157-158. 

By a source of atmospheric pollution we mean an object releasing polluting substances into the air. 

Plants for the production of nitric acid are serious sources of atmospheric pollution in spite of many improvements and the development of numerous combined procedures. As much as 0.30% by volume of oxides of nitrogen may occur in the final gases, even in the case of properly operating absorbers even higher concentrations are sometimes encountered. Nitrogen oxides can also enter into the atmosphere during nitration processes. 

Monaci et al. (1997) performed a lichen-biomonitoring study in Siena by means of two different methods. The pattern of air quality in the study area was examined on the basis of the in situ frequency of different species of epiphytic lichens, i.e. using their species-specific sensitivity to the complex mixture of phytotoxic pollutants in the urban environment. The distribution of trace elements was evaluated quantitatively by an analysis of thalli of a tolerant species, P. caperata, known to be a reliable bioaccumulator of persistent atmospheric pollutants. The values obtained for Al, Ba, Cr, Cu, Fe, Pb and S were significantly higher in Sienese lichens over and above controls. Traffic was found to be the major source of atmospheric pollution. The pattern of trace-elemental deposition did not always coincide with air quality. lAP values were found to reflect essentially the emission of gaseous phytotoxic pollutants in the urban environment. 

Most atmospheric pollution is due to means of transport road vehicles, trains, ships and aircraft. The main pollutants emitted by these sources are CO2, organic volatiles (VOCs), nitrogen oxides (NOJ and particles of heavy metals such as lead or mercury. The main immobile sources of atmospheric pollution are certain kinds of industrial plant, and power stations or heaters that bum fossil fuels. The combustion of fossil fuels releases sulphur compounds (H2S, SO2, etc.) as weU as NO, CO2, VOCs and particulate matter. 

Pyrometallurgical operations require large quantities of energy and are often a source of atmospheric pollution, especially by sulfur dioxide. For some metals, other techniques have been developed in which the metal is extracted from its ore by use of aqueous reactions. These processes are called hydrometalluigy (hydro means "water"). 

The analysis of snow deposited at varying distances from a specific source of atmospheric pollution provides another means of measuring the level of contamination, and in this case, the levels measured are valid only for the time at which precipitation took place. This technique has been used by Kerin [171] to monitor lead pollution in the vicinity of a lead smelter in Yugoslavia. 

The engines used in automotive vehicles of all kinds, and as stationary power sources, consume air and liquid fuel as their energy source, and rely on liquid lubricant and coolant to maintain them in good condition. Another fluid - the exhaust gas - is currently of considerable environmental concern, as a source of atmospheric pollution. So there are five fluids involved in the operation of an engine, all needing filtration for one reason or another ... 

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