Publication Overview
The emissions of CO₂ from power plants equipped with carbon dioxide capture systems are reduced by upwards of 85% compared to equivalent plants without capture. However the full environmental impact of a plant fitted with CO₂ capture will depend also on what changes are induced in emissions of other substances in gaseous, liquid and solid form. Furthermore due to the increase in fuel and chemicals consumption typical for a CCS plant emissions due to the “upstream” and “downstream” processes and particularly those associated with increased fuel use, will also increase. Both these effects need to be taken into account if the technology is to be assessed on a life cycle basis. This study focuses only on the changes which are to be expected in the direct emissions, discharges and solid wastes of substances other than CO₂ from within the boundary of power plants fitted with CO₂ capture
Publication Summary
Baseline data was collected for three types of power plant without capture:
- an Ultra Supercritical (USC) Pulverized Coal (PC) fired steam plant,
- a coal fired integrated gasification and combined cycle power plant (IGCC)
- a natural gas-fired combined cycle power plant (NGCC).
Data for 4 CCS plants for comparison with these baselines was collected for:
- A USC PC plant with post combustion capture using an MEA solvent,
- an oxyfueled USC PC plant using the CO₂ separation and clean up process of Air Products,
- an IGCC plant adapted for CO₂ capture using Selexol to recover the CO₂
- an NGCC plant fitted with post combustion capture again using an MEA solvent.
A total of 37 references were found in the literature and these were used to populate a database of 176 different cases. However complete datasets could not be generated for all of these cases as the amount of information varied quite widely. This data formed the basis for estimation of emissions using the harmonization approach. It is thus expected to yield “average” values based on current experience. The range of values will also give some indication of the best and worst which might be expected and hence also represents the full range of technologies.
