Abstract
The pore size distribution of 4 kinds of shells and 2 kinds of limestone as SO_2 absorbent were measured with pore master mercury porosimeter, and the desulphurization characteristics of above absorbents were studied with thermal-gravimetric analyzer. As a result, the shell lime has higher pore volume with pore diameter above 0.1 micron, while limestone has lower pore volume with pore diameter between 0.008 to 0.2 micron, but the surface area is very high. The bigger pores whose diameters are above 0.1 micron in shell have fewer air-blocked pores, lower gas diffusing resistance, and almost simultaneous and completed reaction. So, the calcium conversion ratios of the shells are greater than those of the limestone. From the test, the shells that have bigger pore size got higher calcium conversion rate, and within the shells, the S3 shell has the best sulphation ability as its bigger specific surface area.
