Dry Removal of SO_2 in Flue Gas by Hydrated Dolomite

摘要

Domestic dolomite sorbents for the SO_2 removal were prepared and the characteristics of sorbents were investigated by TGA,XRD,SEM and BET.To improve SO_2 capture capacity,the dolomite sorbents were calcined,hydrated and recalcined at various conditions.The specific surface area of hydrated sorbents increased with increasing stirring rate,hydration temperature and hydration time.In this work,the hydration process by using ultrasonic wave was conducted at the hydration temperature of 100 deg C for the hydration time of 100-120 min.The specific surface area of sorbent hydrated at the above condition,was increased by 25%,compared to that of unhydrated sorbent and the hydrated sorbent exhibited SO_2 removal capacity of 16 times higher than unhydrated sorbent.The effect of particle size for the sulfidation was examined.As a result,the highest SO_2 removal capacity could be achieved at the particle size of 32-60 mum.The SO_2 removal capacity of sorbent below 32 mum decreased due to sintering at about 850 deg C.