Carbon dioxide (CO2) produced in power generation facilities is considered to be a green house gas. As such, the carbon dioxide produced in the overall power production process generally is sequestered and then recycled for other purposes. In current integrated gasification combined cycle (“IGCC”) technologies, the precombustion capture of carbon dioxide is preferred. Once captured, the carbon dioxide generally may be compressed before transport, disposal, or other use. Specifically, various IGCC designs require the compression of the carbon dioxide before the gas is recycled to, for example, the feed system, the gasifier, or other locations in the overall IGCC process.
The gross power output from an IGCC or other type of power plant is determined by the output of the gas turbine engine(s) operating on a syngas or other fuel. Any parasitical electrical or other type of load in the power plant serves to reduce the net generation output of the power plant. Compression of carbon dioxide, however, generally requires large amounts of auxiliary compression power. This compression is usually provided by electric drives or steam turbines. This type of parasitic load thus results in lower power plant net output and efficiency.
There is thus a desire for an improved power plant and methods of driving compression equipment and other types of plant equipment without being a parasitic load on the IGCC plant as a whole. Such a reduced parasitic load also will increase the net power generation output.