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C1a 3 Crude oil. Burning fuels and cleaner fuels. Learning objectives. Understand what is produced when fuels burn Know what can be done to reduce the problem. Fractions of crude oil.
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C1a 3 Crude oil Burning fuels and cleaner fuels
Learning objectives • Understand what is produced when fuels burn • Know what can be done to reduce the problem
Fractions of crude oil Burned in the refinery to fuel the distillation process, sold as LPG, purified and sold as bottled camping gas Fuel gas Petrol / gasoline Fuel for cars and motorcycles, also used to make chemicals. Naphtha Used to make chemicals. Paraffin / Kerosine Fuel for greenhouse heaters and jet engines, manufacture of chemicals. Diesel fuel Fuel for lorries, trains. Fuel and lubricating oil Fuel for the heating systems of large buildings, fuel for ships, lubricating oil. Bitumen Roofing, and road surfaces.
Burning fuels • Burning – chemical reaction of combustion • Fuel reacts with oxygen • Chemical reaction – new products • Is this a balanced reaction? • Complete combustion propane + oxygen water + carbon dioxide C3H8 + O2 H2O + CO2
Burning hydrocarbons Suction pump ice- water Lime water Candle wax is the hydrocarbon here Liquid collected can be tested with anhydrous cobalt chloride paper (bluepink). any hydrocarbon + oxygen water + carbon dioxide
Greenhouse effect • Sun’s rays enter the Earth’s atmosphere • Heat is reflected back from the Earth’s surface • Heat is absorbed by carbon dioxide (greenhouse gas) and as a result becomes trapped in the Earth’s atmosphere • The Earth becomes hotter as a result
Not just hydrocarbons • Crude oil also contains impurities • Can cause problems • Sulphur (sulfur) • Reacts with oxygen – sulphur dioxide • Poisonous gas • Acidic (acid rain) • Damages engines
Other problems • Incomplete combustion – not enough oxygen • Carbon monoxide • Poisonous gas • Stops red blood cells carrying oxygen • High temp – nitrogen and oxygen react together • Nitrogen oxides • Poisonous gases (acid rain) • Health problems (asthma)
Particulates • Diesel engines – burn bigger hydrocarbons • Don’t always completely burn • Un-burnt hydrocarbons react with oxygen • Particles found in air in towns and cities • Unknown affect on health • Global Dimming
Cleaning up our act • Reduce gases – catalytic convertor • Gases travel over transition metals • Gases react • Power stations react gases with quicklime • Flue gas desulphurisation Carbon monoxide + nitrogen oxides carbon dioxide + nitrogen
Key points • Combustion of hydrocarbons in air produces carbon dioxide and water • Burn in different conditions = different products • Crude oil may contain impurities that have negative effects • Gases released can be treated to reduce harmful effects