CYCLIC CO2 CAPTURE BEHAVIOR OF LIMESTONE MODIFIED BY QINGHAI LAKE SALT DURING LONG-TERM CALCIUM LOOPING CYCLES

A modified sorbent was prepared by a novel hydration impregnation method. Results indicated that hydrating with salt water can obtain enhanced capacity of the sorbents during multiple calcination/carbonation reactions. After 40 cycles, the modified limestone sorbent doped with 2wt% lake salt remained a CO2 capture capacity of 0.34 g of CO2 of sorbent, which was 150% higher than that of natural limestone. XRF and XRD were tested for analyzing the chemical component of the sorbents. A Fixed-bed reactor was applied to test the absorption characteristics of those sorbents. SEM analysis revealed that macropores in this novel sorbent were relatively stable during long-term cycles. A preliminary economic analysis of different modified calcium-based sorbents was conducted, and the results demonstrated that limestone modified by lake salt is a promising scheme for large-scale sorbent production, which is a well cost-effective and pollution free scenario suitable for industrial promotion. (CSPE)