Atmospheric sulfur dioxide

Corrosion by atmospheric sulfur dioxide should be considered in the development and evaluation of protective coatings (267,268). Sulfur dioxide and sulfuric acid therefrom are highly damaging to carbonate building stones (269). 

Smelting releases sulfur dioxide gas from a metal sulfide ore. Before the twentieth century, most of the sulfur dioxide expelled in the smelting process poured out of the factory s smokestacks directly into the atmosphere. Sulfur dioxide in the atmosphere, however, is a powerful greenhouse gas. Today, most of the hot sulfur dioxide gas released in the smelting process is captured, cooled, cleaned, and converted into sulfur trioxide ... 

Hydrogen sulfide is released primarily as a gas and will spread in the air. However, in some instances, it may be released in the liquid waste of an industrial facility. When hydrogen sulfide is released as a gas, it may form sulfur dioxide and sulfuric acid in the atmosphere. Sulfur dioxide can be further broken down and is a major contributor to acid rain. Hydrogen sulfide is estimated to remain in the atmosphere for an average of 18 hours. You will find more about what happens to hydrogen sulfide when it enters the environment in Chapters 4 and 5. 

Mulik, J. D., Todd, G Estes, E., Puckett, R Sawicki, E., Ion Chromatographic Determination of Atmospheric Sulfur Dioxide. Ion Chromatographic Analysis of Environmental Pollutants. Edited by Sawicki, E., Mulik, f. D., Wittgenstein, E., Ann Arbor Science Publishers, Ann Arbor, MI (1978). 

Lindgren, P. F., and P. K. Dasgupta, Measurement of Atmospheric Sulfur Dioxide by Diffusion Scrubber Coupled Ion Chromatography, Anal. Chem., 61, 19-24 (1989). 

The United Kingdom, however, still produces 3 x 106 metric tons of sulfur emissions a year, and atmospheric sulfur dioxide causes further problems... 

TARNISH. A reaction that occurs readily at room temperature between metallic silver and sulfur in any form. The well-known black film that appears on the silverware results from reaction between atmospheric sulfur dioxide and metallic silver, forming silver sulfide. It is easily removable with a cleaning compound and is not a true form of corrosion. Plating with a mixture of silver and indium will increase tarnish resistance. Gold will also tarnish in the presence of a high concentration of sulfur in the environment... 

Summary of Non-Marine Sulfur Emissions. S S values for continental sources of atmospheric sulfur dioxide vary, ranging between -32 and +10 0/00. This makes it difficult to use sulfur isotope ratios to distinguish sulfate from these individual sources. It appears that the f S value for marine biogenic sulfur is much more enriched in the heavier isotope than sulfur from continental origins. Therfore, it should be possible to isotopically distinguish between marine biogenic and continentally-derived sulfur. 

Power plants and refineries are the primary fixed sources of pollutant emissions in most urban areas. However, other industrial sources, distributed throughout the area, also emit substantial amounts of contaminants. Also during the winter months effluents from home heating can add significantly to the pollutant load in the atmosphere. Sulfur dioxide and particulates are emitted from nearly all fixed sources although many of the particulate emissions are controlled by the use of abatement devices and sulfur dioxide by the use of low sulfur fuels. Also, power plants emit large amounts of nitrogen oxides, and refineries, hydrocarbons. 

Bluth G. J. S., Schnetzler C. C., Krueger A. J., and Walter L. S. (1993) The contribution of explosive volcanism to global atmospheric sulfur dioxide concentrations. Nature 366, 327-329. 

Altshuller, P., 1973. Atmospheric sulfur dioxide and sulfate distribution and concentration at urban and nonurban sites in United States. Environ. Sci. Technol., 7 709—712. Bailey, N.J.L., Krouse, H.R., Evans, C.R. and Rogers, M.A., 1973. Alteration of crude oil by waters and bacteria evidence from geochemical and isotope studies. Am. Assoc. Petrol. Geol. Bull., 57 1276—1290. 

Sulfates are discharged into water from mines and smelters, and from kraft pulp and paper mills, textile mills, and tanneries. Atmospheric sulfur dioxide, formed by the combustion of fossil fuels and by metallurgical roasting processes, may contribute to the sulfate content of surface waters. Sulfur trioxide, produced by the photolytic or catalytic oxidation of sulfur dioxide, combines with water vapor to form dilute sulfuric acid, which falls as acid rain . The environmental fate and transport of sulfate are inextricably linked to the physical and chemical processes active in the earth s sulfur cycle. 

Although some sulfuric acid is emitted directly by fuel-burning equipment, most of the sulfur in fuel is oxidized to and emitted as sulfur dioxide (S02). Sulfur dioxide contains sulfur in the ( + IV) oxidation state and dissolves in water to form sulfurous acid (H2S03), a relatively weak acid. In the presence of hydroxyl radicals in the atmosphere, sulfur dioxide is oxidized to sulfur trioxide (S03), which contains sulfur in the (+VI) oxidation state. Sulfur trioxide reacts with water to form H2S04, a strong acid. 

Hocking, D. and Hocking. M.B. 1977. Equilibrium Solubility of Trace Atmospheric Sulfur Dioxide in Water and its Bearing on Air Pollution Injury to Plants. Environmental Pollution, (London), 13, 57-64... 

Results obtained at Research Triangle Park, North Carolina during the last half of 1985 are summarized in Tables I and II. As a first approximation, because data on daily sulfur dioxide concentrations and times-of-wetness were not available, antecedent sulfur dioxide loading to the stone surface was estimated by multiplying the average atmospheric sulfur dioxide concentration by the number of days between rainstorms. 

The atmospheric sulfur dioxide (SO2) concentration over a certain region is 0.12 ppm by volume. Calculate the pH of the rainwater due to this pollutant. Assume that the dissolution of SO2 does not affect its pressure. 

Apply Coal and petroleum products are sometimes contaminated with sulfur. When coal or petroleum containing sulfur is burned, sulfur dioxide (SO2) can be released into the atmosphere. Use the information about the reactions involved in industrial sulfuric-acid production to infer how atmospheric sulfur dioxide contributes to acid precipitation. 

Lake ecosystems are also complex, but they sometimes respond more quickly than do forest ecosystems to reductions in sulfur dioxide emissions. In many lakes, however, the decline in sulfate concentrations is less than expected given the drop in atmospheric sulfur dioxide deposition, and the pH shows surprisingly little change. As Peter Dillon et al. describe in Chapter 4, water quality in lakes in Ontario improved very little despite a major reduction in atmospheric acid deposition because sulfates are carried into the lakes from the surrounding watershed in stream water, especially following drought years. Sulfur dioxide emissions will need to be lowered even more before accumulated sulfates are removed from this system. 

Waste Characteristics and Impacts Atmospheric Emissions - The process has two emissions to the atmosphere sulfur dioxide and acid mist, both of which are released with the waste gas from the final absorber tower. 

Tables 2.3-2.6 and Fig. 2.2 give historic data on corrosion resistance of zinc classified subjectively by environment. The qualitative terms used by authors clearly have different corrosion significance in different parts of the world. Some work for which atmospheric pollution data is available is given in Table 2.7A together with a supplement. Table 2.7B. Averages of six l-year tests in the worldwide ISOCORRAG series, still in progress, have been published, however (Knotkova, 1993) the full data cover steel, copper, and aluminum as well as zinc. The interpretation of measurements of atmospheric sulfur dioxide and chloride is not clear-cut different measurement techniques can give substantially different results, and the relationship between corrosion effects and the particular method of measurement requires further interpretation.

Haynie and Upham (1970) compiled data for the atmospheric sulfur dioxide level, relative humidity, and zinc corrosion rate for eight U.S. cities. Using regression and curve-fitting techniques, they developed the equation ... 

Haynie, F. H., and Upham, J. B. (1970). Effects of atmospheric sulfur dioxide on the corrosion of zinc. Mater. Prot. Performance, 9(8), 35-40. 

Stalker, W. W., Dickerson, R. C., and Kramer, G. D. (1963). Atmospheric sulfur dioxide and particular matter—A comparison of methods of measurement. Ind. Hygiene J., January-February, pp. 68-79. 

Katz, M. 1960. Photoelectric determination of atmospheric sulfur dioxide. Employing dilute starch-iodine solutions. Anal. Chem. 22, 1040-1047. 

Atmospheric sulfur dioxide reacts with water to form sulfiirous acid ... 

More than 30 million tons of SO2 is released into the atmosphere in the United States each year. (By comparison, the eruption of Mount Pinatubo in the Philippines in 1991 spewed 15 million to 30 million tons of SO2 into the atmosphere.) Sulfur dioxide itself is harmful to both human health and property furthermore, atmospheric SO2 can be oxidized to SO3 by any of several different pathways (such as reaction with O2 or O3). When SO3 dissolves in water, it produces sulfuric acid, H2SO4 ... 

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