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Sulphur Dioxide

One kilogram of sulphur in a fuel results in two kilograms of sulphur dioxide in the exhaust. Sulphur dioxide is produced by the combustion of sulphur in the fuel. Further complex chemical reactions in the atmosphere can result in the production of acidic compounds such as sulphuric acid (H2SO4). These compounds are a major cause of ‘acid rain’ which can have damaging effects on the ecology of the earth’s surface as well as causing corrosion damage to surfaces on which condensation occurs.  Typical sulphur content and sulphur dioxide emissions are shown in the following table.

 Sulphur content in fuels and typical SO2 emissions
 FuelTypical % sulphur in fuel Kilograms of sulphur dioxide produced per tonne of fuel Sulphur dioxide content (kg) per GJ 'available' energy (GCV)† Sulphur dioxide content (kg) per MWh thermal input 
 Coal1.2 24 1.08  3.47
 Heavy fuel oil
 40 1.16 3.33
 Gas-oil 0.15 3 0.08 0.24
 Natural gas
 nil nil nil nil
 †Assumes 80% of total energy is 'available' from combustion.

The most effective way of reducing sulphur dioxide emissions is to reduce the amount of sulphur burned in combustion processes; the maximum permitted sulphur content of commercial fuels has been reduced in recent years, and further reductions are scheduled. Pollution abatement techniques are available, and a process known as flue gas desulphurisation (FGD) can extract sulphur dioxide from combustion process exhaust.


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What's New

UK CHP Development Map

UK CHP Development Map

UK CHP Development Map

UK CHP Development Map Screenshot

The UK CHP Development Tool is the latest version of the map, originally developed as a tool aimed at assisting power station developers consider the opportunities for supplying heat and development of combined heat and power (CHP) as required under planning policy. However, it can also be used by both small and large organisations to help identify the locations where the supply of CHP heat would have the greatest potential, and therefore the largest positive environmental impact.

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