Carbon dioxide from hydrocarbon fuels

The most commonly used fuels for combustion are hydrocarbons, materials that are compounds of only hydrogen and carbon. Occasionally, fuels such as alcohols, that contain oxygen, are burned. Wlieti hydrocarbon fuels with or without oxygen arc burned in air (combusted) to completion, the products are water, from the hydrogen part of the fuel, and carbon dioxide, from the complete conversion of the carbon part. If oxygen is present m the fuel, it shows up in the final product as part of either the water or carbon dioxide. 

The two most important environmental hazards faced by humankind today are air pollution and global warming. Both have a direct link with our current overdependence on fossil fuels. Pollutants produced from combustion of hydrocarbons now cause even more health problems due to the urbanization of world population. The net increase in environmental carbon dioxide from combustion is a suspect cause for global warming, which is endangering the Earth—the only known place to support human life. In addition, the import of expensive hydrocarbon fuel has become a heavy burden on many countries, causing political and economic unrest. 

Applications are induced by the barrier properties to gases and vapours, including oxygen, nitrogen, carbon dioxide, helium, hydrocarbons and fuels, flavours, aromas and various chemicals. The sensitivity to moisture very often requires use in multilayer form to protect EVOH from ambient moisture. Applications can be, for example, without claiming to be exhaustive ... 

Ideally, the combustion process would produce only carbon dioxide—from the combustion of coal—or carbon dioxide and water—from the combustion of hydrocarbon fuels such as natural gas and refined peti oleum fuels. In practice, however, fossil fuels contain a percentage of materials other than carbon and hydrogen, such as sulfur, metals (including iron, mercury, and lead), and nonmetals (including phosphorus, silicon, and arsenic). In addition, air used to supply oxygen for combustion also... 

The combustion of fossil fuels must produce carbon dioxide as a product, but does the carbon dioxide have to go into the atmosphere The U.S. Department of Energy (DOE) does not think so it has started a dialogue and research program that unites the government with academia and industry to develop technologies to "sequester" or trap carbon dioxide. In the simplest case, carbon dioxide is removed from the exhaust gas before the gas is emitted into the atmosphere. In more complex scenarios, carbon is removed from hydrocarbon fuels before combustion, producing hydrogen, which then becomes the primary fuel for the plant. 

Products of Combustion For lean mixtures, the products of combustion (POC) of a sulfur-free fuel consist of carbon dioxide, water vapor, nitrogen, oxygen, and possible small amounts of carbon monoxide and unburned hydrocarbon species. Figure 27-12 shows the effect of fuel-air ratio on the flue gas composition resulting from the combustion of natural gas. In the case of solid and liquid fuels, the... 

The increasing number of atomic reactors used for power generation has been questioned from several environmental points of view. A modern atomic plant, as shown in Fig. 28-3, appears to be relatively pollution free compared to the more familiar fossil fuel-fired plant, which emits carbon monoxide and carbon dioxide, oxides of nitrogen and sulfur, hydrocarbons, and fly ash. However, waste and spent-fuel disposal problems may offset the apparent advantages. These problems (along with steam generator leaks) caused the plant shown in Fig. 28-3 to close permanently in 199T. 

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