Characteristics of Spray-Dried K₂CO₃-MgO Solid Sorbent for CO₂ Capture from Power Plant Flue Gas

Abstract

Three K₂CO₃-MgO based solid sorbents were prepared with a spray drying method to prevent the degradation of the chemical reactivity of K₂CO₃-Al₂O₃ sorbents named KEP-CO2P, which were produced in bulk. Their physical properties and reactivity were screened to evaluate their applicability to a 0.5 MWe (2,000 Nm³/h) CO₂ capture pilot plant built for Unit 3 and a 10 MWe (40,000 Nm³/h) CO₂ capture pilot plant built for Unit 8 of the Hadong thermal power station. The CO₂ sorption capacity and percentage utilization of K₂CO₃-MgO based sorbent, Sorb-KM2, was 8.6 wt% (g-CO₂/100 g-sorbent) and 90%, respectively, along with good mechanical strength for fluidized-bed application. Sorb-KM2 was tested using a 2 Nm³/h circulating fluidized bed process to evaluate their applicability to a fluidized bed process, and the chemical and structural characteristics were investigated by PSA, FE-SEM, EPMA and XPS.