Integrated gasification combined cycle

Figure 1. An IGCC plant in Spain.

Integrated gasification combined cycle (IGCC) generates electricity from coal, petroleum or biomass while reducing the amount of air pollutants released. The cycle combines combined-cycle generation with gasification to maximize the efficiency of the fuel, while carbon capture and storage can be incorporated to reduce carbon dioxide emissions.

How it works

First, the fuel is turned into a synthesis gas (also known as syngas) within a gasification chamber. This process also creates steam. The hot syngas is then sent through a cleaning chamber, which removes a large portion of sulfur, mercury and particulate matter. If carbon capture is incorporated, carbon dioxide can also be removed and stored underground or elsewhere.

The cleaned fuel is then sent to a gas turbine and generator to produce electricity. The excess heat from the exhaust gases is used to create more steam, which is added to the initial batch of steam and sent to a steam turbine to generate electricity as well.

Flexibility

of Fuel

An IGCC plant can handle various types of fuel, including coal, waste, coke, petroleum, biomass, or a mix of these. It can also burn natural gas in the turbine as a secondary fuel while the primary fuel components are under maintenance.

of Product

Aside from only generating electricity, the plant can also divert the waste heat from its processes to provide district heating throughcogeneration.

Plants may also be optimized to produce other useful products such as synthetic natural gas, hydrogen, and other chemicals.

Moreover, if carbon capture is incorporated, the captured carbon dioxide from the cleaning stage can be used elsewhere.

A short video from the Tennessee Valley Authority shows the general process below:

For Further Reading

• Simple cycle gas plant
• Gas turbine
• Cogeneration
• Steam
• Heat exchanger
• Or explore a random page