15 Fossil Based and Renewable Fuels

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Fossil Based and Renewable Fuels Requirements for fuel The most important requirements, for fuel for IC engines have to meet, are: 1) Plentiful availability, high processing and dressing facility, low costs and minimum environmental impact; 2) High heating values per unit mass and unit volume and easy transport and storage; 3) rapid start and development of combustion processes at any ambient temperature; 4) complete and speedy combustion, without formation of harmful pollutant; 5) Absence of carbon and corrosive deposits on surfaces of combustion chamber; So the availability of liquid fuels derived from crude oil distillation and their relatively easy processing, in order to meet previous listed requirements, made them up to now be the main (over 90%) energy source for IC engines. However, starting from last decades, it became clear that natural resources such as coal, petroleum and natural gas took millions of year to form naturally and cannot be replaced as fast as they are being consumed. Therefore alternative fuels, also known as renewable (i.e. fuels that can be naturally reproduced on a time scale which can sustain their consumption rate) have been extensively tested on engines. Fossil Fuel for Engines Over 90% of fuel used in IC engines is derived by fraction distillation from the raw petroleum coming from oil wells. It consists of several hydrocarbon types of different molecular weights, including a small fraction of organic compounds containing: sulphur, nitrogen, etc... The real composition of crude oil widely differs according to its source. On the basis of its residue after distillation, which may be mainly paraffin, asphalt or a mixture of the two, crudes are called paraffin, naphthenic or mixed based, with a large variety of composition for each group.…