Simulation of the carbonate looping power cycle

Carbonate Looping is a promising post-combustion capture process involving the separation of CO(2) from the flue gas of a coal-fired power plant at high temperatures (600-700 degrees C) using the reversible exothermic CaO carbonation reaction and the endothermic calcination reaction of CaCO(3). The core of the carbonate looping process is a dual fluidized bed reactor in which the CO(2) acceptor material (CaO) is transported between the carbonator (CO(2) absorption) and regenerator (CO(2) desorption). Due to the heat requirements for the regenerator, the carbonate looping acts as a CO(2) separation unit and an add-on power plant, thereby offering the opportunity for increasing the site electricity production while inflicting only a low electric efficiency penalty on the total power plant. However, the quantity and quality of the Carbonate Looping heat sources differ significantly from a conventional coal-fired power plant. This paper presents the design and simulation of the carbonate looping steam cycle for a large coal-fired plant. The simulation involves the coupling of the carbonate looping reactor model from Aspen Plus with the steam cycle in EBSILON Professional code which is a mass and energy balance cycle calculation program specifically tailored for steam cycle calculations. The resulting simulation includes penalty deduction for the Air Separation Unit and the CO(2) conditioning unit, resulting in a net efficiency of 39.2% and while increasing the net power input from 1052 MW(e) to 1533 MW(e), an addition of 481 MW(e) for the retrofitted power plant.(C)2008 Elsevier Ltd. All rights reserved