A Carbonator Model for CO2 Capture Based on Results from Pilot Tests. Part II: Deactivation and Reaction Model

Abstract

Carbonate looping (CaL) is a promising technology for CO2 capture from carbon-intensive processes. The efficacy of CaL strongly depends on sorbent kinetics and carrying capacity. In this work, we present a novel particle sub-model to predict carbonation behavior of CaO for CO2 capture in a CaL process. The sub-model deals with sorbent deactivation and reaction kinetics. We follow an original approach to non-ideal calcination and introduce a new calculation methodology for sorbent aging that considers fluctuations in sorbent circulation and make-up rates. The sub-model presented in this article is used in conjunction with the reactor model of Part I to predict the CO2 capture efficiency of a CaL pilot plant. The results of the particle sub-model were validated with experimental data from thermogravimetric analysis (TGA) and pilot tests at the 300-kWth scale. Our study provides new insights for more accurately selecting assumptions and better modeling sorbent behavior in CaL systems.

Keywords: CO2 capture, Calcium looping, indirectly heated carbonate looping, sorbent deactivation, thermogravimetric analysis, pilot testing.