Concentration Of Sulfur Oxides Research Articles

AIR POLLUTION WITH SULFUR OXIDES FROM INDUSTRY IN SOUTH-WESTERN AND SOUTH-EASTERN REGIONS OF BULGARIA

Restructuring of industrial production and the concrete environmental measures such as fuel switching facilities and replacement of process equipment in the energy-intensive industries, the installation of new or increased efficiency of existing treatment facilities have caused emissions into the atmosphere to decrease significantly. However, the concentration of sulfur oxides in air showed no significant improvement, despite reduced emissions.

Modification of high-sulfur petroleum coke with oil shale and its conversion products

The decrease in the concentration of sulfur oxides in the gaseous products of the combustion of high-sulfur petroleum coke was studied. The aqueous dispersions of shale from the Baltic Basin, shale semi-coke, shale ash, and calcium oxide were studied as the additives that decrease the formation of gaseous sulfur oxides. A change in the rate of combustion of impregnated samples, as compared with that of the initial coke, was considered.

Evaluation of the Variability in Chemical Transport Model Performance for Deposition and Ambient Concentrations of Nitrogen and Sulfur Compounds

Air quality models are increasingly used to develop estimates of dry and wet deposition of sulfate and nitrate in watersheds (because of lack of measurements) in an effort to determine the acidifying deposition load into the aquatic systems. These models need to be rigorously evaluated to ensure that one can rely on the modeled quantities instead of the measured quantities. In the United State (U.S.), these models have been proposed for use in establishing national standards based on modeled quantities. The U.S. Environmental Protection Agency (EPA) is considering aquatic acidification as the main ecological endpoint of concern in determining the secondary national ambient air quality standards for nitrogen oxides and sulfur oxides. Acidification is tied to depositions of sulfur and nitrogen, which are linked to ambient concentrations of the elements. As EPA proposes to use a chemical transport model in linking deposition to ambient concentration, it is important to investigate how the currently used chemical transport models perform in predicting depositions and ambient concentrations of relevant chemical species and quantify the variability in their estimates. In this study, several annual simulations by multiple chemical transport models for the entire continental U.S. domain are evaluated against available measurement data for depositions and ambient concentrations of sulfur oxides and reactive nitrogen species. The model performance results vary by evaluation time-scale and geographical region. Evaluation of annualized quantities (annual average ambient concentrations and annual total depositions) suppresses the large variances shown in the evaluation using the observation’s native shorter-term time-scales (e.g., weekly). In addition, there is a large degree of bias and error (especially for deposition fluxes) in the modeling results that brings to question the suitability of using air quality models to provide estimates of deposition loads. Variability in the ratio of deposition to ambient concentration, so-called the Transference Ratio that EPA has proposed to use in linking deposition to ambient concentration, is also examined. Our study shows that the Transference Ratios as well as total reduced nitrogen deposition, another modeled parameter EPA proposed to use in the process of determining the new secondary standard, vary considerably by geographical region and by model simulation.

Alberta’s Oil Sands: Hard Evidence, Missing Data, New Promises

Pitched battles are a regular occurrence in northern Alberta, Canada, as development of the province’s oil sands continues to expand. One ongoing battle—with another salvo launched in February 2011 with the leak of a European Commission report1—concerns how dirty oil sands are, relative to other fuels. Another concerns the influence of the oil sands industry in monitoring its own activity.2 In an effort to cut through the rhetoric of health advocates, industry representatives, environmentalists, government officials, and local residents, the Royal Society of Canada (RSC) selected and covered expenses for an expert panel to winnow out the facts. In a report issued 15 December 20103 the panel cited substantial evidence that efforts to extract oil from the Alberta deposits have degraded air, land, and water quality to varying degrees. The extent of the degradation is sometimes controversial; water quality data, in particular, are subject to differing interpretations and attributions of causality. However, the panel says that, based on publicly available evidence, there appear to be no significant human health threats to the general population either now or from development anticipated in the next decade or so. But the panel also warns that their conclusions come with a major caveat: there are major gaps in health and environmental data, risk assessments, government oversight, information transparency, industry efforts, and disaster preparedness. The health of the region could hinge on these gaps being addressed, particularly since, according to Travis Davies, a spokesman for the Canadian Association of Petroleum Producers, 97% of projected oil extraction and processing is still to come. After the RSC panel reviewed reams of publicly available information on factors such as health status, air and water pollution, greenhouse gas emissions, land disturbance, and energy and water consumption, it concluded that “[t]he claim by some critics of the oil sands industry that it is the most environmentally destructive project on earth is not supported by the evidence. However, for Canada and Alberta, the oil sands industry involves major environmental issues on many fronts which must be addressed as a high priority.”3p293

Assessing the Impacts of Long-Range Sulfur and Nitrogen Deposition on Arctic and Sub-Arctic Ecosystems

For more than a decade, anthropogenic sulfur (S) and nitrogen (N) deposition has been identified as a key pollutant in the Arctic. In this study new critical loads of acidity (S and N) were estimated for terrestrial ecosystems north of 60 degrees latitude by applying the Simple Mass Balance (SMB) model using two critical chemical criteria (Al/Bc = 1 and ANCle = 0). Critical loads were exceeded in large areas of northern Europe and the Norilsk region in western Siberia during the 1990s, with the more stringent criterion (ANCle = 0) showing the larger area of exceedance. However, modeled deposition estimates indicate that mean concentrations of sulfur oxides and total S deposition within the Arctic almost halved between 1990 and 2000. The modeled exceeded area is much reduced when currently agreed emission reductions are applied, and almost disappears under the implementation of maximum technically feasible reductions by 2020. In northern North America there was no exceedance under any of the deposition scenarios applied. Modeled N deposition was less than 5 kg ha(-1) y(-1) almost across the entire study area for all scenarios; and therefore empirical critical loads for the eutrophying impact of nitrogen are unlikely to be exceeded. The reduction in critical load exceedances is supported by observed improvements in surface water quality, whereas the observed extensive damage of terrestrial vegetation around the mining and smelter complexes in the area is mainly caused by direct impacts of air pollution and metals.

Impact of Sulfur Oxides on Mercury Capture by Activated Carbon

Recent field tests of mercury removal with activated carbon injection (ACI) have revealed that mercury capture is limited in flue gases containing high concentrations of sulfur oxides (SOx). In order to gain a more complete understanding of the impact of SOx on ACl, mercury capture was tested under varying conditions of SO2 and SO3 concentrations using a packed bed reactor and simulated flue gas (SFG). The final mercury content of the activated carbons is independent of the SO2 concentration in the SFG, but the presence of SO3 inhibits mercury capture even at the lowest concentration tested (20 ppm). The mercury removal capacity decreases as the sulfur content of the used activated carbons increases from 1 to 10%. In one extreme case, an activated carbon with 10% sulfur, prepared by H2SO4 impregnation, shows almost no mercury capacity. The results suggest that mercury and sulfur oxides are in competition for the same binding sites on the carbon surface.

Investigations into the kinetics and mechanism of gas–solid state processes in MgO–MgR 2O 4 (R: Al, Cr, Fe) spinels–SO 2–O 2 system

In refractory ceramics magnesia-spinel materials continue to play an important role for both economic and research reasons. Although their basic properties are considered to be well-known, problems connected with production technology and improvement of application remain to be solved. The aim of this work is to describe and explain the behaviour of spinels in gaseous environment having high concentration of sulfur oxides. Thermodynamic analysis of chemical reactions in MgO–MgR 2O 4 (R: Al, Cr, Fe) spinels–SO 2–O 2 system as well as kinetic investigations and phase analysis of reaction products were carried out. Kinetic investigation results enabled to compare the chemical reactivity of spinels: MgAl 2O 4, MgCr 2O 4, MgFe 2O 4 and MgO at temperature 773, 1073 and 1273 K. On the basis of shrinking core model activation energy of the reaction MgO + SO 3 → MgSO 4 was calculated. Kinetic measurements confirmed the influence of early suggested phase changes on chemical reactivity of spinels within characteristic temperature range and revealed unexpectedly high reactivity of MgFe 2O 4 in comparison with the other spinels and MgO. It points out the criteria of selecting raw materials in basic refractory ceramics.

Promotion of surface SO x on the selective catalytic reduction of NO by hydrocarbons over Ag/Al 2O 3

The promotion of sulfur oxides on the selective catalytic reduction (SCR) of NO by hydrocarbons in the presence of a low concentration of sulfur oxides over Ag/Al 2O 3 has been investigated by a flow reaction test and in situ infrared spectroscopy. When the C 3H 6 (or C 10H 22) + NO + O 2 feed-flow reaction was tested, maximum NO reduction was below 30% over fresh Ag/Al 2O 3. After the addition of SO 2 to the feed flow, conversion increased slightly. Conversion increased further after SO 2 was cut-off from the feed flow. This demonstrated that the increase in NO reduction activity of the catalyst was related to SO x adsorbed on the catalyst. SO x adsorbed on the catalytic surface (1375 cm −1) was detected by IR spectroscopy and was stable within the temperature range. NCO species, as an intermediate in NO reduction, on SO x -adsorbed Ag/Al 2O 3 in a C 3H 6 + NO + O 2 feed flow was observed in in situ IR spectra during the elevation of the reaction temperature from 473 to 673 K, while it was only observed at 673 K on fresh Ag/Al 2O 3 under the same experimental conditions. We suggest that SO x in low concentrations depressed the combustion of reductants by contaminating hydrocarbon combustion active sites on the catalyst, resulting in an increase in NO reduction efficiency of the reductants.

Influence of small‐ and large‐scale variables on the chemical and isotopic compositions of urban rainwater, as illustrated by a case study in Ashdod, Israel

The source of air pollution must be identified to select the appropriate monitoring activities and remedial measures. The present case study illustrates how analyses of (1) regional‐scale synoptics and air mass trajectories, (2) local‐scale atmospheric measurements (wind direction and speed, air temperature, dust load, sulfur and nitrogen oxide concentrations in the air, rain amount, and intensity) and (3) chemical and isotopic compositions of rainwater from 46 rain events, collected in the coastal city of Ashdod, Israel, were used to identify the various sources contributing to rainwater salts and contaminants and their timing. Rainwater affected by the Mediterranean Sea was characterized by a large marine fraction of salts, high chloride concentrations, and low values of δ18O and δD. These rain events were associated with the Cyprus Low system, which typically prevails in midwinter. Rainwater affected by continental sources had a small contribution of marine salts, high bicarbonate and calcium concentrations, and high values of δ18O and δD. These rains were related to continental trajectories from the Red Sea and north African coast prevailing during the fall and spring. Rainwater affected by anthropogenic sources was characterized by low marine fraction, high sulfate concentrations, and low values of δ34S. Whereas remote anthropogenic source was associated with the Red Sea trough system and were characterized by high nitrate concentrations (representing desert dust), the local anthropogenic source was characterized by high air concentrations of sulfur oxides at the local monitoring stations and high potassium and low nitrate concentrations. The identification of local anthropogenic source suggests that measures taken to reduce emissions from local oil refineries and power stations are likely to reduce the overall air pollution in the study area.

STUDY ON ATMOSPHERIC DIFFUSION OF SULFUR OXIDES IN ASIA

Sixty percents of people in the world live in Asian area, and their economic activities earn twenty four percents of the total GDP all over the world. As the population increases and the economic activities, emissions of sulfur oxides and nitrogen oxides from combustion are increasing and the emissions cause not only local pollution but also global environmental pollution.It is important to calculate the concentration of sulfur oxides that is emitted from the stack of large point sources. In this paper, a software package was developed to calculate the diffusion of sulfur oxides which is emitted from Asian large point sources by using the Japanese air pollution model, and this package was applied to diffusion problems by large point sources China, Korea and India's. The result is displayed as figures with GIS and the diffusion in each country was discussed.

Protecting the atmosphere from open-hearth emissions

Protecting the environment from harmful industrial wastes in the next century has become one of the most important and complex problems of our time. Pollution of the atmosphere, the oceans, and the ground poses a threat to plant and animal life worldwide. A significant portion of the harmful substances discharged into the atmosphere is generated by metallurgical facilities. Metallurgical plants account for 20-25 % of all harmful atmospheric emissions, this figure climbing to more than 50 % near metallurgical combines and large factories. These emissions can be broken down as follows within the countries comprising the CIS (Commonwealth of Independent States): 25 % particulate matter; 30-40% carbon monoxide; 6% sulfur oxides; 8% nitrogen oxides. A large (15-20%) contributor to harmful emissions in the metallurgical industry is open-hearth furnace operation. The concentration of dust in the flue gases of open-hearth shops varies broadly in relation to different factors and can reach 50 g/m 3. Most of the dust consists of iron oxides, the concentration of which can reach 92 %. Also present in the dust are oxides of calcium, magnesium, aluminum, manganese, lead, zinc, phosphorous, and silicon. The concentrations of oxides of sulfur and nitrogen in OH flue gases fluctuate broadly, depending on different factors. The concentration of nitrogen oxides can reach 1 g/m 3, while the concentration of sulfur oxides can go as high as 0.08 g/m 3. The OH flue gases also contain carbon monoxide, polycyclic aromatic hydrocarbons, and benzo/cdpyrene. Since up to 65 % of domestic steel is made in OH and two-bath furnaces and since only 40 % of the OH furnaces are equipped with gas-cleaning systems, it is evident that protecting the atmosphere from the emissions generated by OH shops is a serious problem. This makes the recent book by S. I. Arkhireeva and A. F. Onushkevich, entitled Protecting the Atmosphere from Open-Hearth Emissions [Metallurgiya, Moscow (1992)] a very timely publication. The book consists of a brief introduction and four chapters. The first chapter details the design and operating characteristics of OH and two-bath steelmaking furnaces, along with the sources of harmful atmospheric emission associated with their operation. The second chapter presents quantitative and qualitative characteristics of periodic and random emissions of particulate matter, sulfur anhydride, nitrogen oxides, and other harmful substances during different regimes of operation of OH and two-bath furnaces. The third chapter is devoted to an explanation of the methods and equipment used to remove dust, nitrogen oxides, and benzo/~/pyrene from OH and two-bath-furnace waste gases. This chapter also gives the performance indices of this equipment and indices reflecting the efficacy of various systems designed to clean OH flue gases. The fourth and final chapter covers measures that can be taken to prevent pollution of the atmosphere by OH furnace operation: the principal methods currently being used to reduce harmful emissions, along with certain measures related to sanitation. Also discussed in the chapter are the conditions under which emissions are dispersed in the atmosphere and measures that can prove helpful under unfavorable weather conditions. At the conclusion of this chapter, the authors present information on the organization and activities of pollution-control services at plants in the ferrous metallurgy sector. The book contains 25 illustration, 13 tables, and 16 formulas for performing the necessary mathematical calculations.

Pulmonary Effects of Sulfur Oxides on the Surface of Copper Oxide Aerosol

The authors have developed a system that generates copper oxide aerosol similar to the primary emissions from smelters. The surface of the ultrafine copper oxide aerosol is coated with a layer of sulfur oxides consisting of sulfate, S(VI), and sulfite, S(IV). Guinea pigs were exposed to this sulfur oxide layered copper oxide aerosol, and pulmonary mechanical functions were measured by using the Amdur-Mead method. The concentration of sulfur oxides on the aerosol was determined by using a flame photometric detector system. Although sulfuric acid was not found in this system, S(IV) at concentrations as low as 0.36 µmol/m3 delivered as a surface layer caused prolonged changes in pulmonary mechanical functions.

PULMONARY EFFECTS OF SULFUR OXIDES ON THE SURFACE OF COPPER OXIDE AEROSOL

The authors have developed a system that generates copper oxide aerosol similar to the primary emissions from smelters. The surface of the ultrafine copper oxide aerosol is coated with a layer of sulfur oxides consisting of sulfate, S(VI), and sulfite, S(IV). Guinea pigs were exposed to this sulfur oxide layered copper oxide aerosol, and pulmonary mechanical functions were measured by using the Amdur-Mead method. The concentration of sulfur oxides on the aerosol was determined by using a flame photometric detector system. Although sulfuric acid was not found in this system, S(IV) at concentrations as low as 0.36 mumol/m3 delivered as a surface layer caused prolonged changes in pulmonary mechanical functions.

Mortality from asthma and chronic bronchitis associated with changes in sulfur oxides air pollution.

Death certificates issued in Yokkaichi, Japan, during the 21 yr from 1963 until 1983 were surveyed to determine the relationship between changes in air pollution and mortality due to bronchial asthma and chronic bronchitis. The following results were obtained. In response to worsening air pollution, mortality for bronchial asthma and chronic bronchitis began to increase. Mortality due to bronchial asthma decreased immediately in response to improvement of pollution, whereas mortality due to chronic bronchitis decreased to the level in the control area 4 to 5 yr after the concentration of sulfur dioxide (SO2) began to satisfy the ambient air quality standard. In the polluted area, mortality due to bronchial asthma in subjects who were 20 yr of age was higher during the period in which higher concentrations of sulfur oxides were prevalent.

A trajectory puff model of sulfur transport for eastern North America

A trajectory puff model of long-range transport of sulfur oxides in eastern North America computes trajectories from modified surface geostrophic winds, taking advantage of the relatively fine space and time scales of routine surface observations. Annual and seasonal average concentrations of sulfur oxides and their wet deposition were computed for 1979. Comparison of simulated annual wet deposition with monitored values yielded reasonably good agreement. Also, the seasonal trends computed by the model followed the trends in observations.

Assessment of the Health Effects of Atmospheric Sulfur Oxides and Particulate Matter: Evidence from Observational Studies

Steadily rising energy costs have increased the need for reliable information on the health effects of atmospheric sulfur oxides and particulate matter. Because ethical and practical considerations limit studies of this question under controlled conditions, observational studies provide an important part of the relevant information. This paper examines the currently available epidemiologic evidence from population studies of the health effects of these pollutants. Nonexperimental studies also have important limitations, including the inability to measure accurately the exposure burden of free living individuals, and the potential for serious confounding by other factors affecting health. We begin with a discussion of some of these methodologic issues. The evidence is then reviewed, first in association with fluctuations in 24 hr mean concentration of sulfur oxides and particulate matter, and then in association with differences in mean annual concentration. In the last section, this evidence is summarized and used to approximate the exposure-response relationship linking pollutant concentrations with mortality and morbidity levels.

Assessment of the health effects of atmospheric sulfur oxides and particulate matter: evidence from observational studies.

Steadily rising energy costs have increased the need for reliable information on the health effects of atmospheric sulfur oxides and particulate matter. Because ethical and practical considerations limit studies of this question under controlled conditions, observational studies provide an important part of the relevant information. This paper examines the currently available epidemiologic evidence from population studies of the health effects of these pollutants. Nonexperimental studies also have important limitations, including the inability to measure accurately the exposure burden of free living individuals, and the potential for serious confounding by other factors affecting health. We begin with a discussion of some of these methodologic issues. The evidence is then reviewed, first in association with fluctuations in 24 hr mean concentration of sulfur oxides and particulate matter, and then in association with differences in mean annual concentration. In the last section, this evidence is summarized and used to approximate the exposure-response relationship linking pollutant concentrations with mortality and morbidity levels.

MAP3S: An investigation of atmospheric, energy related pollutants in the Northeastern United States

The Multi-State Atmospheric Power Production Pollution Study (MAP3S) is a major new atmospheric research program of the U.S. Energy Research and Development Administration. The goal of the MAP3S program is to develop and demonstrate an improved, verified capability to simulate the present and potential future changes in pollutant concentration, atmospheric behavior and precipitation chemistry as a result of pollutant releases to the atmosphere from large-scale power production processes, primarily coal combustion. A major motivation of this program is to be able to provide those agencies charged with the task of meeting the nation's energy needs with the knowledge required to assess alternative strategies for generating power while ensuring ample protection of human health and adequate preservation of the natural environment Since coal is the most abundant domestic fossil energy resource and since electric power production is a major and growing sector of our energy economy, this study focuses on the effects of emissions from coal fired electric power plants, particularly sulfur oxide emissions. The study domain is the high population, energy intensive northeastern quadrant of the United States. Research projects are underway to measure present sulfur oxide concentrations and composition, to assess the potential for long range transport to investigate transformation processes in plumes from point and urban sources, to sample precipitation chemistry and improve understanding of scavenging mechanisms and to develop numerical models that can simulate future air quality on sub-continental scales given patterns of anticipated combustion emissions.

Microbiological Assay Method for Sulfate by Means of Cultivation of Escherichia coli B (H). III. Correlation between Sulfur Content in Orange Leaves and Concentration of Sulfur Oxides in Air

Sulfur content in orange leaves was determined by microbiological assay method using Escherichia coli B (H), and concentration of sulfur oxides in air was discussed. Sulfur content in each orange leaf of one grown-up tree gave large standard deviation (11-29%), and no significant correlation was observed between this sulfur content and concentration of sulfur oxides in air. On the other hand, some significant correlation was observed between sulfur content in orange leaves of young trees grown in a pot (pot-test) and concentration of sulfur oxides in air. These result suggested that the sulfur content in orange leaves obtained by this pot-test method was useful as an index of concentration of sulfur oxides in air.

The Influences of Air Pollution on Some Cultural Assets. I. : On the Air-Pollutional Measurement by the Filter Parer Method and the Influence of Air Pollution on Metallic Luster

Concentration of sulfur oxides and nitrogen dioxide in atmosphere was measured by alkaline filter paper method in summer (June 1968) and winter (January 1969) at 100 places in Kyoto, including the grounds of shrines and temples in which the designated Important Cultural Properties were placed. A rather higher concentration of both sulfur oxides and nitorogen dioxide was generally observed in winter than in summer. Further effect of these air-pollutants on metallic luster of these Properties was investigated, and the rate or decrease in metallic luster was about 10% lower on the average in winter than in summer. Although it was supposed that the weather conditions might be largely responsible in decreasing the metallic luster, correlation between the concentration of sulfur oxides and the rate of decrease in metallic luster was observed generally in both summer and winter (correlation coefficient found, 0.458 in summer, 0.416 in winter). There was no correlation between the concentration of nitrogen dioxide and decrease in the luster of metals (correlation coefficient found, 0.180 in smmer, 0.138 in winter).