Exhaust gas pollution exhaust sources in various large-scale industrial facilities such as petroleum refineries, natural gas processing plants, petrochemical plants and chemical production plants. However, these are often referred to as flue gases. Catalytic converters in cars intend to break down the pollution of exhaust gases using a catalyst. Scrubbers in ships intend to remove the sulfur dioxide (SO) of marine exhaust gases. The regulations on marine sulfur dioxide emissions are tightening, however only a small number of special areas worldwide have been designated for low sulfur diesel fuel use only. One of the advantages claimed for advanced steam technology engines is
Engine knocking reduction, exhaust gas recirculation, appropriate calibration of the engine's ignition timing schedule, and careful design of the engine's combustion chambers and cooling system as well as controlling the initial air intake temperature. The addition of certain materials such as lead and thallium will suppress detonation extremely well when certain fuels are used. The addition of tetraethyllead (TEL), a soluble organolead compound added to gasoline was common until it was discontinued for reasons of toxic pollution. Lead dust added to the intake charge will also reduce knock with various hydrocarbon fuels. Manganese compounds are also used to reduce knock with petrol