No abstract

A previous IEA GHG study of CO 2 capture from a pulverized coal (PC) power plant using an amine solvent for flue gas scrubbing has been used as the basis for calculations of the reductions in electricity and CO 2 avoidance costs that might be achievable through improved thermodynamic integration between the CO 2 capture plant and the steam cycle, the use of a solvent with lower regeneration energy requirements and solvent storage to allow rapid load changes and electricity 'storage'. It was predicted that the efficiency penalty for CO 2 capture for PC plant with flue gas scrubbing using an amine solvent can be reduced to 20 per cent (from 28 per cent) with improved thermodynamic integration and lower-energy solvent, giving a 10 per cent reduction in electricity costs, from $63.5/MW h to $57.4/MW h, and a 25 per cent reduction in the cost of CO 2 avoided, from $45/t to $34/t. These values are both lower than predictions for the gasifier-based coal power plant in the original IEA GHG study. Reductions in the average cost of electricity of 6-7 per cent were estimated using solvent storage, giving a cost of electricity of $56.73/MW h and $33/t CO 2 avoided for an integrated plant with monoethanolamine (MEA) as the solvent. Also, CO 2 venting would allow an additional 20-25 per cent increase in output to be maintained indefinitely when $/MW h electricity prices were 2-3 times greater than the $/t penalty for CO 2 discharges.

No abstract

No abstract

Research since the 1960s on the deposition of droplets from wet steam is reviewed, concentrating mainly on low-pressure turbines but also covering the limited work related to nuclear high-pressure turbines. The context is first set, outlining the motivation in terms of blade erosion and, to a lesser extent, wetness losses. Details of measurements in turbines and in simulated turbine flows are followed by descriptions of theoretical work on the main inertial and turbulent deposition mechanisms; possible additional contributory mechanisms are summarized. A major combined experimental and computational effort in the 1980s led to broad agreement between measured and calculated fog deposition fractions in low-pressure turbine final stages, attributed largely to the development of more accurate droplet size measurement and computational fluid dynamics techniques. An attempt has been made to correlate advances with the history of steam turbine development and to speculate on the future of deposition studies in the light of recent theoretical developments and trends in power generation.