for the proposed 800 MW Combined Cycle Power Plant ...

CO 2 Capture Study
For 800 MW Power Plant – Tjeldbergodden
3.4 Off Gas Plume Dispersion
Stack Gas from Absorber Towers
The stack gas has been passed through the absorber towers, therefore it will
have been saturated with water as well as having had the majority of its acidic
components removed.
These acidic components include oxides of nitrogen as well as carbon
dioxide. Thus the final effluent gas will be air from which a portion of the
oxygen has been removed and which is saturated with water vapour at 37°C.
The gas is not hazardous to life, however upon contact with cooler air, a
visible plume of water vapour will form. Under freezing conditions this could
form ice on exposed cold surfaces.
The need for plume dispersal by heating or dilution with ambient air, will
depend on the location of the plume in relation to access roads and work
areas, where it could reduce visibility; and structures, where icing could lead
to overloading of such structures. It is recommended that this be studied in a
later phase.
3.5 Emissions and Effluents Introduction
The Econamine FG Plus SM (EFG+) process produces three main
emissions/effluents:
• Absorber Stack Emissions: MEA and Ammonia
• Reclaimer Waste
• DCC Excess Water containing dissolved carbon dioxide
3.5.1 Absorber Stack Emissions
The expected concentrations of MEA and ammonia in the absorber stack gas
are as follows.
Expected Emissions
Expected
Emissions
MEA
Ammonia
ppmv 0.2 23
3.5.2 Reclaimer Waste
Heat stable salts (HSS) are formed in the EFG+ process due to acid-base
reaction between MEA and different acid products present in the flue gas or in
the solution, including:
• SO 2 and SO 3 in the flue gas
• The NO 2 portion of NO x in the flue gas
• Small quantities of acids generated by oxidation MEA
CB2005-0022_Final Report.Doc