3D Printed Limestone Monoliths for CO2 Capture in Calcium Looping

Abstract

In this experiment, limestone monoliths were 3D printed using a novel limestone mixture, then tested inside of a fixed bed reactor. This represents to the author’s knowledge the first use of 3D printed monoliths in calcium looping. Four monoliths with different infill geometries were tested and compared against a random packing and limestone powder. Comparison was made through the adsorptive capacity of CO₂, and the pressure drop across the column. Calcination was done at 850 °C, under pure N₂, whereas carbonation was conducted at 650 °C with 15% CO₂, balance N₂. The adsorptive performance of these monoliths was in line with the traditional limestone powder on a millimole CO₂/g_sorbent basis, but the pressure drop across the column was reduced by ∼58% on average.