This thesis investigates the optimisation of an Integrated Gasification Combined Cycle (IGCC) power station that is employing Geological Sequestration of Carbon Dioxide (CO2SEQ). IGCC power stations are similar to conventional Natural Gas Combined Cycle (NGCC) power stations but receive their fuel from the gasification of coal as opposed to natural gas. These power stations typically are used in areas where the supply of natural is limited or the price of a substitute solid feedstock is substantially lower.
An IGCC power station combines two technologies to produce electricity for the domestic market. The gasification of feedstock to produce synthesis gas (syngas) for commercial and industrial use has existed since the late 1790s. Combined Cycle Gas Turbines (CCGTs) combine a gas turbine with a steam turbine powered by the waste heat from the gas turbine. A combination of these two technologies can produce electricity more efficiently than the present super-critical thermal power stations.
The by-product of combustion from any carbon based fuel is carbon dioxide. In a global effort to reduce the amount of carbon dioxide released into the atmosphere trials in the sequestration of carbon dioxide are underway. In 2002 Australia produced 539.2 million tonnes of carbon dioxide equivalent emissions. Over half of this came from the electricity generation sector. There has been interest within the electricity sector in Australia to reduce carbon emissions and CO2SEQ looks to be one choice.
Presently an IGCC power station is the best suited plant to operate in conjunction with a carbon sequestration project due to desirable flow streams in the process. This thesis analyses the various sections of an IGCC power station and recommends changes to increase the overall cycle efficiency of the process.