Assessment of Carbon Capture Options for Super-Critical Coal-based Power Plants

Abstract

Power generation is one of the industrial sectors with major contribution to greenhouse gas emissions. For climate change mitigation, a special attention is given to the reduction of CO2 emissions by applying capture and storage techniques in which CO2 is captured and then stored in suitable safe geologic locations. Carbon capture and storage (CCS) technologies are expected to play a significant role in the coming decades for curbing greenhouse gas emissions and to ensure a sustainable development of power generation and other energy-intensive industrial sectors (e.g. cement, metallurgy, petro-chemical etc.). This paper evaluates super-critical coal-based power plants with and without carbon capture. The analysis is geared toward quantification of main plant performance indicators such as: fuel consumption, gross and net energy efficiency, ancillary energy consumption, carbon capture rate, specific CO2 emissions, capital costs, specific capital investments and operational costs etc. For CCS configurations, two post-combustion CO2 capture options were considered. The first option is based gas-liquid absorption using a chemical solvent (methyl-diethanol-amine – MDEA etc.). The second option is based on calcium looping cycle, in which the carbonation/calcination sequence of CaO/CaCO3 system is used for carbon capture. The power plant case studies investigated in the paper produces around 950 – 1,100 MW net power with at least 90 % carbon capture rate. The mathematical modelling and simulation of the whole power generation schemes will produce the input data for quantitative techno-economic and environmental evaluations of power plants with carbon capture (similar power plant concept without CCS was used as reference for comparison). Mass and energy integration tools were used to assess the integration aspects of evaluated carbon capture options in the whole power plant design, to optimise the overall energy efficiency and to evaluate the main sources of energy penalty for CCS designs.