Emission source, sulfur dioxide

Sulfur Dioxide EPA Method 6 is the reference method for determining emissions of sulfur dioxide (SO9) from stationary sources. As the gas goes through the sampling apparatus (see Fig. 25-33), the sulfuric acid mist and sulfur trioxide are removed, the SO9 is removed by a chemical reaction with a hydrogen peroxide solution, and, finally, the sample gas volume is measured. Upon completion of the rim, the sulfuric acid mist and sulfur trioxide are discarded, and the collected material containing the SO9 is recovered for analysis at the laboratory. The concentration of SO9 in the sample is determined by a titration method. 

Pollution prevention is always preferred to the use of end-of-pipe pollution control facilities. Therefore, every attempt should be made to incorporate cleaner production processes and facilities to limit, at source, the quantity of pollutants generated. The choice of flash smelting over older technologies is the most significant means of reducing pollution at source. Sulfur dioxide emissions can be controlled by ... 

Specifically, rapid urbanization, with the associated growth in industry and transportation systems, has increased regional concerns with regard to emissions of sulfur dioxide and nitrogen oxides. According to estimations for the year 2000, sulfur dioxide emissions in Asia surpassed the emissions of North America and Europe combined. The primary manmade source of sulfur and nitrogen in the Asia-Pacific region is fossil fuel combustion in... 

The global natural flux of sulfur compounds to the atmosphere has recently been estimated to be about 2.5 Tmol yr1 (1) which is comparable to the emissions of sulfur dioxide (SO2) from anthropogenic sources (2). A substantial amount of the natural sulfur contribution (0.5-1.2 Tmol yr1) is attributed to the emission of dimethylsulfide (DMS) from the world s oceans to the atmosphere (3.4). One of the major uncertainties in this estimate is due to a scarcity of DMS and other sulfur data from the Southern Hemisphere, particularly the Southern Ocean region between about 40°S and the Antarctic continent, which represents about one fifth of the total world ocean area. 

Dan Luss I believe that there is still a need to study pathological behavior, especially in systems where it is caused by the interaction of the fluid flow and chemical reaction. For example, a major problem in the design and operation of a trickle-bed reactor is the presence of local hot spots, which have caused several major explosions. I ve just been involved in litigation that resulted from a reactor explosion it caused 15 million worth of damage at a plant in Corpus Christi. Most of the existing models in the literature are oversimplified and cannot predict this important feature. A model that will predict this behavior would be an important contribution. Another example is the self-ignition of coal piles, which is the major source of emission of sulfur dioxide into the atmosphere in South Africa. It s definitely desirable to get a better quantitative understanding of this behavior and how to prevent it. 

As noted earlier, an accurate selection of sources requiring control can best be achieved through the application of the Air Quality Display Model for each AQCR of interest. It is estimated that the total one-time cost of such an exercise at a level of accuracy necessary to predict source sulfur dioxide control requirements for each of the 245 AQCR s would be about 10 million with an additional annual maintenance cost of 500 thousand to allow for emission inventory changes. For comparison. 

During the thermally driven differentiation of the Earth into core-mantle-crust, numerous reactions would have produced oxidized forms of iron, sulfur and carbon. These would have contributed to the redox chemistry in the early planet development. Volcanic and hydrothermal emission of sulfur dioxide, SO2, delivered oxidants to the oceans and atmosphere. Photodissociation of water vapor in the atmosphere have undoubtedly provided a small but significant source of molecular oxygen. Furthermore, UV-driven ferrous iron oxidation could have been coupled to the reduction of a variety of reactants, for instance, CO2 (Figure 16). 

Water is an obvious example of a substance that is global in scope. In this text, specific sources of pollution (stack emissions of sulfur dioxide) and small-scale natural processes (ammonia emissions from a feedlot) are considered only to the extent that they are significant in aggregate at the global scale. Further, the term "cycles" in the title should not imply that only closed, steady-state systems are considered, but should emphasize the importance of understanding where substances come from and what they are turned into. 

The eastern coast of China is the highest emission region in the Asian domain and possibly, with sharply decreasing sulfur dioxide emissions in Central Europe and East USA, in the whole world. This emission coincides with both energy production and population growth in this part of China. The other parts of China, such as the western part, are not so abundant in population and industrial sources as the eastern coast and these differences point out the spatial heterogeneity in emission of sulfur dioxide. As an example we can cite estimates of spatial distribution of SO2 emission in China from 1990 until 1995 with 1° x 1° Longitude-Latitude (LoLa) resolution (Bai Naibin, 1997). 

Gas and liquid emissions and mine tailing are the principal pollution sources sulfur dioxide release, particulate, diffused dust, cooling wastewater, ash production, fluorine, lead, cadmium and zinc emissions. 

An airshed or source area is an area where significant portions of emissions result in deposition of air pollutants to a region (www.epa.gov). In North America, emissions of sulfur dioxide are highest in the mid-western... 

Figure 3.2. Annual emissions of sulfur dioxide and nitrogen oxides for the source area of the Hubbard Brook Experimental Forest. The source area was determined by 24-hour back trajectory analysis. Shown are emissions from both U.S. and Canadian sources...

Utility systems as sources of waste. The principal sources of utility waste are associated with hot utilities (including cogeneration systems) and cold utilities. Furnaces, steam boilers, gas turbines, and diesel engines all produce waste from products of combustion. The principal problem here is the emission of carbon dioxide, oxides of sulfur and nitrogen, and particulates (metal oxides, unbumt... 

The 1990 Amendments to the U.S. Clean Air Act require a 50% reduction of sulfur dioxide emissions by the year 2000. Electric power stations are beheved to be the source of 70% of all sulfur dioxide emissions (see Power generation). As of the mid-1990s, no utiUties were recovering commercial quantities of elemental sulfur ia the United States. Two projects had been aimounced Tampa Electric Company s plan to recover 75,000—90,000 metric tons of sulfuric acid (25,000—30,000 metric tons sulfur equivalent) aimuaHy at its power plant ia Polk County, Elorida, and a full-scale sulfur recovery system to be iastaHed at PSl Energy s Wabash River generating station ia Terre Haute, Indiana. Completed ia 1995, the Terre Haute plant should recover about 14,000 t/yr of elemental sulfur. 

Plant nutrient sulfur has been growing in importance worldwide as food production trends increase while overall incidental sulfur inputs diminish. Increasing crop production, reduced sulfur dioxide emissions, and shifts in fertilizer sources have led to a global increase of crop nutritional sulfur deficiencies. Despite the vital role of sulfur in crop nutrition, most of the growth in world fertilizer consumption has been in sulfiir-free nitrogen and phosphoms fertilizers (see Fertilizers). 

Human-made sources cover a wide spectrum of chemical and physical activities and are the major contributors to urban air pollution. Air pollutants in the United States pour out from over 10 million vehicles, the refuse of over 250 million people, the generation of billions of kilowatts of electricity, and the production of innumerable products demanded by eveiyday living. Hundreds of millions of tons of air pollutants are generated annu ly in the United States alone. The five main classes of pollutants are particulates, sulfur dioxide, nitrogen oxides, volatile organic compounds, and carbon monoxide. Total emissions in the United States are summarized by source categoiy for the year 1993 in Table 25-10. 

EPA Method 6C is the instrumental analyzer procedure used to determine sulfur dioxide emissions from stationaiy sources (see Fig. 25-30). An integrated continuous gas sample is extracted from the test location, and a portion of the sample is conveyed to an instrumental analyzer for determination of SO9 gas concentration using an ultraviolet ( UV), nondispersive infrared (NDIR), or fluorescence analyzer. The sample gas is conditioned prior to introduction to the gas analyzer by removing particulate matter and moisture. Sampling is conducted at a constant rate for the entire test rim. 

For sources having a large component of emissions from low-level sources, the simple Gifford-Hanna model given previously as Eq. (20-19), X = Cqju, works well, especially for long-term concentrations, such as annual ones. Using the derived coefficients of 225 for particulate matter and 50 for SO2, an analysis of residuals (measured minus estimated) of the dependent data sets (those used to determine the values of the coefficient C) of 29 cities for particulate matter and 20 cities for SOj and an independent data set of 15 cities for particulate matter is summarized in Table 20-1. For the dependent data sets, overestimates result. The standard deviations of the residuals and the mean absolute errors are about equal for particulates and sulfur dioxide. For the independent data set the mean residual shows... 

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