Emission control, vehicle

See also Acid Ram Air Quality, Indoor Atmosphere Automobile Performance Climatic Effects Emission Control, Vehicle Emission Control, Power Plant Environmental Economics Environmental Problems and Energy Use Gasoline and Additives Transportation, Evolution of Energy Use and Turbines, Gas. 

See also Batteries Capacitors and Ultracapacitors Electric Motor Systems Emission Control, Vehicle Environmental Problems and Energy Use Flywheels Fuel Cells Fuel Cell Vehicles Flybrid Vehicles Materials Transportation, Evolution ofEnergy Use and. 

See also Air Pollution Emission Control, Vehicle Energy Management Control Systems Government Intervention in Energy Markets. 

Georgia Institute of Technology Emission Control, Vehicle Traffic Flow Management... 

For these reasons, CEC and DOE concluded that the only cost-effective method of getting alcohol fueled vehicles would be from original equipment manufacturers (OEM). Vehicles produced on the assembly line would have lower unit costs. The OEM could design and ensure the success and durabihty of the emission control equipment. 

S. Albu, "California s Regulatory Perspective on Alternate Euels," 13th North American Motor Vehicle Emissions Control Conf (Tampa, Fla., Dec. 11—14, 1990), Mobile Source Division, California Air Resources Board, El Monte, Calif. 

Gasoline composition may also be regulated in Europe. A tripartite initiative is being carried out among the European Commission, the oil industry, and the automotive industry. Based on an analysis of the required improvements in air quaUty, new regulations are to be written that control vehicle emissions and fuel composition into the twenty-first century. 

Automotive Emission Control Catalysts. Air pollution (qv) problems caused by automotive exhaust emissions have been met in part by automotive emission control catalysts (autocatalysts) containing PGMs. In the United States, all new cars have been requited to have autocatalyst systems since 1975. In 1995, systems were available for control of emissions from both petrol and diesel vehicles (see Exhaust control, automotive). 

Emission Control Catalysts. An appHcation of growing importance for cerium is as one of the catalyticaHy active components used to remove pollutants from vehicle (autoexhaust) emissions (36). The active form of cerium is the oxide that can be formed in situ by calciaation of a soluble salt such as nitrate or by deposition of slurried oxide (see Exhaust control, automotive). 

On-Board Diagnostics. State of California regulations require that vehicle engines and exhaust emission control systems be monitored by an on-board system to assure continued functional performance. The program is called OBD-II, and requires that engine misfire, the catalytic converter, and the evaporative emission control system be monitored (101). The U.S. EPA is expected to adopt a similar regulation. 

Engines are also designed to use either gasoline or methanol and any mixture thereof (132—136). Such a system utilizes the same fuel storage system, and is called a flexible fueled vehicle (EEV). The closed loop oxygen sensor and TWC catalyst system is perfect for the flexible fueled vehicle. Optimal emissions control requires a fuel sensor to detect the ratio of each fuel being metered at any time and to correct total fuel flow. 

Emission Control Technologies. The California low emission vehicle (LEV) standards has spawned iavestigations iato new technologies and methods for further reducing automobile exhaust emissions. The target is to reduce emissions, especially HC emissions, which occur during the two minutes after a vehicle has been started (53). It is estimated that 70 to 80% of nonmethane HCs that escape conversion by the catalytic converter do so during this time before the catalyst is fully functional. 

In the United States, regulation of emissions from new automotive vehicles has followed the prototype-replicate route. The argument for routine annual automobile inspection is that cars should be regularly inspected for safety (brakes, lights, steering, and tires) and that the additional time and cost required to check the car s emission control system during the same inspection will be minimal. Such an inspection certainly pinpoints cars whose emission control system has been removed, altered, damaged, or deteriorated and force such defects to be remedied. The question is whether... 

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. 

The buyers of motor vehicles have been substantially positive concerning the need to have cleaner running vehicles. Although the required emission control devices and other mandated safety equipment have increased the cost of new motor vehicles, sales have not been significantly effected. The current environmental awareness and concern are evidence of the general population s new found knowledge and acceptance of both mobile and stationary source emission controls. 

A current vehicle fuel system designed for evaporative emission control should address enhanced SHED, running loss, and ORVR emission level requirements (see Table 1). A typical vehicle fuel system is shown in Fig. 4. The primary functions of the system are to store the liquid and vapor phases of the fuel with acceptable loss levels, and to pump liquid fuel to the engine for vehicle operation. The operation of the various components in the fuel system, and how they work to minimize evaporative losses during both driving and refueling events, is described below. 

Fig. 4. Representative vehicle fuel system with evaporative emission control...

During vehicle operations similar to those experienced during the three day diurnal evaporative test outlined in Fig. 1, the following operations occur in the evaporative emission control system ... 

Fuel system components involved in the refueling process include the fuel tank, filler pipe, filler cap, vapor control valve, liquid-vapor discriminator (LVD) valve, and the carbon canister [27,28]. During vehicle refueling, which is monitored during the integrated refueling test as outlined in Fig. 1, the following operations occur in the evaporative emission control system ... 

The use of activated carbon canisters in the control of running loss evaporative emissions will be presented through the use of an example vehicle application. In this example, the vehicle to be studied is a representative standard size sedan equipped with a 3.0 liter, V6 engine and a 72 liter (18 gallon) fuel tank. The vehicle is assumed to have an evaporative emission control system similar to the one presented in Section 3. 

A vehicle fuel vapor control system must be designed to meet both driving and refueling emission level requirements. Due to the nature of hydrocarbon adsorption, this emission control is a continuous operation. 

Catalytic Converter an air pollution abatement device that removes pollutants from motor vehicle exhaust either by oxidizing them into carbon dioxide and water or reducing them to nitrogen. A typical catalytic oxidizer for auto emission control is illustrated in the sidebar figure. 

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