NRG Energy, Inc. (Princeton, N.J.) and Powerspan Corp. (Portsmouth, N.H.; edlinks.chemengonline.com/6902-541) plan to demonstrate, at commercial scale, Powerspan’s ECO2 technology for capturing CO2 from conventional coal-fired power plants. To date, CO2 -capture demonstrations on coal plants have been conducted at pilot scale (1 – 5 MWe). The planned demonstration, which will be conducted at NRG’s WA Parish plant near Sugar Land, Texas, on fluegas (FG) equivalent to that from a 125 MW unit, is expected to capture and sequester about 1-million ton/yr of CO2, which will then be used in enhanced-oil recovery operations in the Houston, Texas area.
In the ECO2 process, CO2 is captured from FG by scrubbing with an aqueous ammonia solution, which absorbs CO2 by forming ammonium bicarbonate (CE, July 2006, p. 14). Powerspan’s ECO2 facility will be designed to capture 90% of the incoming CO2 and is expected to be operational in 2012.