Control diesel-powered vehicles

Control of diesel-powered vehicles is parhally accomplished by fuel modification to obtain reduced sulfur content and cleaner burning and by proper tuning of the engine using restricted fuel settings to prevent overfueling. 

Ball, D.J. and Stack, R.G., Catalysts for diesel powered vehicles. In Catalysis and Automotive Pollution Control II, (Ed Crucq, A.) Elsevier Science Publishers, Amsterdam, 337-51 (1991). 

PM - perhaps the most characteristic emission of diesel emissions -is responsible for the black smoke traditionally associated with diesel-powered vehicles. Diesel Engine Generated particles are subject to diesel emission regulations worldwide and, along with NOx, have become the current focus in diesel emission control technology. 

With internaJ-combustion engines, automatic transmissions are frequently used these are easily justified when vehicles must make many moves during the day. Smooth as is the control afforded by automatic transmissions, it is neveriheless inferior to that provided by electric trucks, especially those with solid-state controls. Gasoline and diesel power are also used, but mostly for outdoor equipment and very-heavy-duty units. 

Although it is possible to improve catalytic converters in gasoline-powered vehicles and to develop exhaust control devices for diesel-fueled vehicles and even aircraft, development in these areas is slow. Extensive research efforts in these areas are desperately needed and should be strongly encouraged. However, in reality, implementation of these devices will be far in the future and the problems of today are increasing. 

Alternatively it may take the form of a ceramic or metallic monolith, of which a variety of physical shapes is available monoliths are now widely used as supports for the active catalyst, which lines the channels which permeate the structure. They find particular application for the control of exhaust from vehicles powered by internal combustion or diesel engines. If the catalyst particles are small enough, a fast flow of reactants causes the bed to expand and the particles to move about like molecules in a liquid. We then have a fluidised bed reactor, which affords a more uniform temperature profile than is possible in fixed bed reactors, and is therefore more apposite to strongly exothermic reactions. 

The diesel engine has many advantages when used as the power source in heavy transport vehicles, but a disadvantage is the emission of pollutants. As the exhaust emission limits become stricter, the need for more effective emission control systems becomes urgent. 

Major sources of acidic precursors (SO2 and NO ) in Singapore include power stations, petroleum refineries, other industries and motor vehicles. Control of these pollutants isregulatedby the Clean Air Act of December 1971. Emissions ofS02 are controlled by restricting the sulfur content of automotive diesel and industrial fuel... 

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