FUEL FOR GAS TURBINES

The fuels usually consumed in gas turbines are either in liquid or dry gas forms and, in most cases, are hydrocarbons. In special cases non-hydrocarbon fuels may be used, but the machines may then need to be specially modified to handle the combustion temperatures and the chemical composition of the fuel and its combustion products.

Gas turbine internal components such as blades, vanes, combustors, seals and fuel gas valves are sensitive to corrosive components present in the fuel or its combustion products such as carbon dioxide, sulphur, sodium or alkali contaminants.

The fuel can generally be divided into several classifications:-

• Low heating value gas.
• Natural gas.
• High heating value gas.
• Distillate oils.
• Crude oil.
• Residual oil.

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