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

Abstract

Three K 2 CO 3 -MgO based solid sorbents were prepared with a spray drying method to prevent the degradation of the chemical reactivity of K 2 CO 3 -Al 2 O 3 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 Nm 3 /h) CO 2 capture pilot plant built for Unit 3 and a 10 MWe (40,000 Nm 3 /h) CO 2 capture pilot plant built for Unit 8 of the Hadong thermal power station. The CO 2 sorption capacity and percentage utilization of K 2 CO 3 -MgO based sorbent, Sorb-KM2, was 8.6 wt% (g-CO 2 /100 g-sorbent) and 90%, respectively, along with good mechanical strength for uidized-bed application. Sorb-KM2 was tested using a 2 Nm 3 /h circulating uidized bed process to evaluate their applicability to a uidized bed process, and the chemical and structural characteristics were investigated by PSA, FE-SEM, EPMA and XPS.

Structural and kinetic analysis of CO2 sorption on NaNO2-promoted MgO at moderate temperatures

“…These alkali salts can be classified into four categories, i.e., single components [23][24][25][26][27], double salts [28][29][30][31], triple salts [32][33][34][35] and multiple salts [36,37]. For K 2 CO 3 -doped sorbents, recent studies indicate that the CO 2 sorption ability was increased to 10.2-11.7 wt% [38,39]. Na 2 CO 3 and NaNO 3 co-doped MgO presented higher capacity (15 wt%), which was mainly attributed to the formation of the sodium-magnesium double carbonate (Na 2 Mg(CO 3 ) 2 ) and the additional promoting effect of NaNO 3 [29].…”