Gasoline powered

A mobile source of air pollution can be defined as one capable of moving from one place to another under its own power. According to this definition, an automobile is a mobile source and a portable asphalt batching plant is not. Generally, mobile sources imply transportation, but sources such as construction equipment, gasoUne-powered lawn mowers, and gasoline-powered tools are included in this category. 

The emissions from a gasoline-powered vehicle come from many sources. Figure 6-12 illustrates what might be expected from an uncontrolled (1960 model) automobile and a controlled (1983 or later model) automobile if it complies with the 1983 federal standards (7). With most of today s automobiles using unleaded gasoline, lead emissions are no longer a major concern. 

Catalytic afterburners are currently used primarily in industry for the control of solvents and organic vapor emissions from industrial ovens. They are used as emission control devices for gasoline-powered automobiles (see Chapter 31). 

Because mobile sources of air pollution are capable of moving from one local jurisdiction to another, they are usually regulated by the national government. In the United States, state or local agencies can have more restrictive standards, if they choose. Through 1990, only the state of California had established standards more restrictive than the U.S. federal standards, and these only for gasoline-powered automobiles. 

Gasoline-powered motor vehicles outnumber all other mobile sources combined in the number of vehicles, the amount of energy consumed, and the mass of air pollutants emitted. It is not surprising that they have received the greatest share of attention regarding emission standards and air pollution control systems. Table 25-2 shows the U.S. federal emission control requirements for gasoline-powered passenger vehicles. 

Would you expect to find the same chemical composition of the hydrocarbons from the exhaust of a gasoline-powered automobile as that of gasoline in the vehicle s tank Why What would be the effect on emissions from a gasoline-powered vehicle if it was designed to be operated on leaded fuel and an unleaded fuel was used ... 

What would be the effect on emissions from a gasoline-powered vehicle if it was designed to be operated on unleaded fuel and a leaded fuel was used ... 

When gasoline-powered automobiles are modified to burn a fuel such as ethanol alone, they are known as dedicated ethanol vehicles—risky investments for buyers who have concerns about future availability. For example, Brazil s Proalcool program promoted and heavily subsidized ethanol, and thus dedicated ethanol vehicles, from 1975 to 1988. Once the subsidies were curtailed and then eliminated (estimates of the costs of the subsidy to the government range from 7 to 10 billion), shortages resulted. Many of the owners of ethanol-dedicated vehicles either had to junk or retrofit the vehicles to run on gasoline, and the sales of ethanol-dedicated vehicles went from 50 percent of the market in 1988 to 4 percent by mid-1990. 

Photochemical smogs arise worldwide because of the action of sunlight on emissions from gasoline-powered vehicles. Decreased visibility, increased morbidity, and crop damage as a result of photochemical smogs led to introduction of the catalytic converter on automobiles in the United States. This has had only a small impact on the occurrence of photochemical smogs in the United States. 

To hasten development of batteries for electric vehicles, Chiysler, Ford, and General Motors formed the U.S. Advanced Batteiy Consortium (USABC). In 1991 USABC, battery manufacturers, the Electric Power Research Institute (EPRI), and the U.S. Department of Energy (DOE) launched a joint research effort to identify, develop and license promising batteiy technology for electric vehicles—vehicles with the range, performance and similar costs of gasoline-powered vehicles. 

Transportation accounts for about one-fourth of the primary energy consumption in the United States. And unlike other sectors of the economy that can easily switch to cleaner natural gas or electricity, automobiles, trucks, nonroad vehicles, and buses are powered by internal-combustion engines burning petroleum products that produce carbon dioxide, carbon monoxide, nitrogen oxides, and hydrocarbons. Efforts are under way to accelerate the introduction of electric, fuel-cell, and hybrid (electric and fuel) vehicles to replace sonic of these vehicles in both the retail marketplace and in commercial, government, public transit, and private fleets. These vehicles dramatically reduce harmful pollutants and reduce carbon dioxide emissions by as much as 50 percent or more compared to gasoline-powered vehicles. 

One of the most common impurities in coastal areas which acts in a chemical manner rather than a physical one is salt water. However, with the ever-increasing spread of the chemical industries, and the stepped-up use of gasoline powered vehicles, the problem of chemical degradation are also of interest particularly in inland areas. While plastics in general are corrosion resistant, the multiplicity of chemical agents which can be in the air in industrial atmospheres, plus the chemical nature of the various plastics indicates that it cannot be assumed that all plastics are chemically resistant to all atmospheres. 

Table 7-18(c) Gasoline powered chain-saw housing resulting in Nylon 6 ot 6/6... 

Hexane may be expected to comprise around 2% of the VOCs in urban air polluted with hydrocarbons from automobile emissions or other combustion byproducts (Barrefors and Petersson 1993). The -hexane concentrations in urban air will typically be approximately 60% of the concentrations of benzene (Daisey et al. 1994). Close proximity to the exhaust systems of cars or other gasoline-powered vehicles can lead to exposures to increased concentrations of -hexane. Under rush-hour conditions, the concentrations in the interior air of buses will tend to be lower (55 g/m3 or 19.8 ppbv) than the interior levels in cars (69 g/m3 or 24.9 ppbv) or the air around persons riding motorcycles (106 g/m3 or... 

DaimlerChrysler s efforts to make a gasoline reformer work was slightly disappointing so the carmaker announced it would concentrate its efforts on methanol, signing on to a program advanced by its partners in the Alliance. Since then, DaimlerChrysler demonstrated a gasoline-powered fuel cell Jeep. 

In fact, the idea of electric cars is not new. In the early days of the automohile, electric cars were more common than gasoline-powered cars. The production of electric cars peaked in 1912, hut then completely stopped in the 1930s. 

Natural gas (NG) consists of 85-95% methane (CH ), which is the simplest hydrocarbon. NG is the cleanest burning alternative fuel. Exhaust emissions from NG vehicles are much lower than those from gasoline-powered vehicles. Combustion of NG reduces carbon dioxide content compared with diesel, but the lost efficiency when the Otto process is used means that carbon dioxide emissions increase. All in all combustion of NG in a gasoline engine gives rise to about as much carbon dioxide as the combustion of diesel in a diesel engine, measured in units of energy. 

Figure 5. Comparison of the driving ranges for a vehicle powered by various battery systems or a gasoline-powered combustion engine.

Gas-phase tailpipe emission rates from gasoline-powered automobiles with and without catalytic converters were 6.55 and 177 pg/km, respectively (Schauer et al, 2002). 

California Phase 11 reformulated gasoline contained benzo[i]fluoranthene at a concentration of 280 pg/kg. Particle-phase tailpipe emission rate from a noncatalyst-equipped gasoline-powered automobile was 32.7 pg/km (Schauer et af, 2002). 

The gas-phase tailpipe emission rate from California Phase II reformulated gasoline-powered automobile equipped with a catalytic converter was 124 pg/km (Schauer et al., 2002). 

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