Fossil fuel sulfur dioxide emissions

Because biomass is an inherent part of the carbon cycle, combustion of biomass reduces air pollution. The carbon dioxide that is produced during combustion was recently fixed into the biomass material, and thus from a life cycle perspective, CO emissions are reduced by 90% compared with fossil fuels. Sulfur dioxide and... 

Sulfur dioxide emissions resulting from fossil fuel can have negative effects on urban air quality and create acid rain that harms aquatic life. These emissions arc nonexcludable in that there is no private action that a particular individual can take to avoid this impact, and they are nonrival in that their effect on any one individual does not preclude or offset their effect on any other. 

Acid rain is caused primarily by sulfur dioxide emissions from burning fossil fuels such as coal, oil, and natural gas. Sulfur is an impurity in these fuels for example, coal typically contains 2-3% by weight sulfur.1M Other sources of sulfur include the industrial smelting of metal sulfide ores to produce the elemental metal and, in some parts of the world, volcanic eruptions. When fossils fuels are burned, sulfur is oxidized to sulfur dioxide (SO2) and trace amounts of sulfur trioxide (SC>3)J21 The release of sulfur dioxide and sulfur trioxide emissions to the atmosphere is the major source of acid rain. These gases combine with oxygen and water vapor to form a fine mist of sulfuric acid that settles on land, on vegetation, and in the ocean. 

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 major anthropogenic sources of sulfur dioxide emissions are fossil fuel and biomass burning, iron and non-ferrous metal smelting and sulfur acid production. The natural emissions from volcano eruptions and massive forest fires should be also taken into account if any occur in the considered period. 

In view of the considerable interest in sulfur dioxide reduction to sulfur both in this country and abroad, Allied Chemical extended the use of this technology to control sulfur dioxide emissions from other metallurgical operations as well as from fossil fuel combustion. The experience gained in design, construction, and operation of the large Canadian facility provided the perspective for continuing process research and parallel engineering development. 

The EPA Method 6 provides procedures for measuring sulfur dioxide emissions from stationary sources where the gas sample is extracted from the exhaust stack. Ammonia, water-soluble cations, and fluorides cause interferences with SOx measurements. Method 6A concerns sulfur dioxide, moisture, and carbon dioxide measurements from fossil fuel combustion sources by chemically separating the SO2 and CO2 components, where different reagent chemicals are used. Method 6C discusses the use of instrument analyzers to measure... 

The primary cause of acid rain is the sulfur dioxide emission from fossil-fiiel combustion. Sulfur dioxide forms because fossil fuels, especially coal, contain sulfur impurities their combustion produces sulfur dioxide (SO2) ... 

Figure 2.7 shows the 2002 national summary of sulfur dioxide emissions by source sectors prepared by the U.S. Environmental Protection Agency (EPA), with input from numerous state and local air agencies, from Native Americans, and from industry [95]. As the figure indicates, SO2 comes primarily from electricity generation, fossil fuel combustion, and industrial processes. 

Most of the world s electricity requirements are met by burning fossil fuels, using the heat generated by nuclear reactors or hydroelectric power, all of which have environmental consequences. Fossil fuels produce carbon dioxide, which contributes to the greenhouse effect and climate change. Many fossil fuels, especially coal, contain sulfur which results in sulfur dioxide emission and acid rain (Chapter 8). 

Even if new technologies are developed to rid fossil-fuel power plants of sulfur dioxide emissions, one large problem remains. Identify and briefly discuss this problem. 

Chemists have found ways to reduce sulfur dioxide emissions from fossil fuels. They now produce Tow-sulfur versions of petrol and diesel. In power stations that burn fossil fuels, the sulfur is removed from the fuel before burning. Alternatively sulfur dioxide can be removed from the waste gases before they are released to the atmosphere through tall chimneys. 

The abatement of sulfur dioxide emissions is a major problem in most industrialized nations that use fossil fuel for power generation. It has been shown that over 35 million tons of SO2 were emitted into the atmosphere in 1970 in the United States [73]. Electric power generation using fossil fuel was the single largest contributor (55 %), while copper and lead smelters processing sulfide ores accounted for about 10% of the total emission. 

Acid deposition occurs when sulfur dioxide and nitrogen oxide emissions are transformed in the atmosphere and return to the earth in rain, fog or snow. Approximately 20 million tons of SOj are emitted annually in the United States, mostly from the burning of fossil fuels by electric utilities. Acid rain damages lakes, harms forests and buildings, contributes to reduced visibility, and is suspected of damaging health. 

Power plant emissions result from the comhustion of fossil fuels such as coal, gas, and oil. These emissions include sulfur dioxide (SO,), nitrogen oxides (NO.,), particulate matter, and hazardous air pollutants, all of which are subject to environmental regulations. Another emission is carbon dioxide (CO,), suspected of being responsible for global warming. 

The remaining. SO percent or less ot supply must have an average emission rate below the system average for fossil-fuel-emitted sulfur dioxide, nitrogen oxide, and carbon dioxide. 

Sulfur dioxide Is formed primarily from the Industrial and domestic combustion of fossil fuels. On a global scale, man-made emissions of SOj are currently estimated to be 160-180 million tons per year. These emissions slightly exceed natural emissions, largely from volcanic sources. The northern hemisphere accounts for approximately 90% of the man-made emissions (13-14). Over the past few decades global SOj emissions have risen by approximately 4%/year corresponding to the Increase In world energy consumption. 

The principal cause of acid rain is the combustion of fossil fuels that produce sulfur and nitrogen emissions. The primary sources are electrical power plants, automobiles, and smelters. Power plants produce most of the sulfur emissions and automobiles most of the nitrogen emissions. Other sources of acid rain include nitrogen fertilizers, jet aircraft, and industrial emissions. Just as in our discussion of ozone, numerous reactions are involved in the formation of acid rain. The process can be understood by considering the transformation of sulfur and nitrogen oxides into their respective acidic forms sulfuric acid and nitric acid. Sulfur, present up to a few percent in fuels such as coal, is converted to sulfur dioxide when the fuel is burned. The sulfur dioxide reacts with water to produce sulfurous acid, H,SO ,, that is then oxidized to sulfuric... 

Scientists have discovered that air pollution from the burning of fossil fuels is the major cause of acid rain. Acidic deposition, or acid ram, as it is commonly known, occurs when emissions of sulfur dioxide (SO ) and oxides of nitrogen (NOx) react in the atmosphere with water, oxygen, and oxidants to form various acidic compounds. This mixture forms a mild solution of sulfuric acid and nitric acid. Sunlight increases the rate of most of these reactions. 

Title IV of the Clean Air Act Amendments of 1990 calls for a 10 million ton reduction in annual emissions of sulfur dioxide (S02) in the United Stales by the year 2010, which represents an approximately 40 percent reduction in anthropogenic emissions from 1980 levels, Implementation of Title IV is referred to as the Acid Rain Program the primary motivation for this section of the Clean Air Act Amendments is to reduce acid precipitation and dry deposition. To achieve these reductions, the law requires a two-phase tightening of the restrictions placed on fossil-fuel-lired power plants. 

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