... this it is meant that we take a long chain hydro-carbon such as bitumen into smaller, more useful hydro-carbons such a petroleum. There are several types of cracking including; * Thermal - you heat large hydrocarbons at high temperatures (sometimes high pressures as well) until they break apart. * Steam - high temperature steam (1500 degrees Fahrenheit / 816 degrees Celsius) is used to break ethane, butane and naphtha into ethylene and benzene, which are used to manufacture chemicals. * Visbreaking - residual from the distillation tower is heated (900 degrees Fahrenheit / 482 degrees Celsius, 755 Kelvin), cooled with gas oil and rapidly burned (flashed) in a distillation tower. This process reduces the viscosity of heavy weight oils and produces tar. Hydro-carbon fuels have a major problem. Most hydro-carbon fuels have a negative effect on the environment. By using petrol or diesel we produce carbon dioxide CO2 and H2O, as ...

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