Process Simulation of Calcium Looping With Indirect Calciner Heat Transfer

Abstract

In calcium looping (CaL), calcium oxide (CaO) is used as a sorbent for carbon dioxide (CO 2). The CO 2 reacts with CaO to produce calcium carbonate (CaCO 3) in a carbonator. The CaCO 3 is then sent to another reactor, a calciner, where the CaCO 3 is calcined, producing CaO (which is returned to the carbonator for another cycle) and more or less pure CO 2 , which is removed from the system. Conventional CaL with direct heat transfer using oxy-combustion has an unwanted energy penalty. However, if the heat could be transferred indirectly to the calciner, the energy penalty associated with oxy-combustion could be avoided. In this work, Aspen Plus is used to simulate the CaL process with indirect heat transfer. The results confirm that such a scheme could give an energy penalty lower than for example amine scrubbing or oxy-combustion.