采用湿法机械制粒机制备水泥支撑钙基吸收剂颗粒,在鼓泡床上研究其循环碳酸化活性及磨损,在颗粒碰撞装置上研究其碰撞强度,并结合扫描电镜、氮吸附分析微观结构.研究表明,制粒过程掺杂10%高铝水泥制备的吸收剂高温下具有较好的抗烧结特性,多次循环后孔隙衰竭较弱.其850℃、N2及950℃、100%CO2煅烧下的循环钙转化率均优于原始石灰石.成型颗粒鼓泡床内抗磨损能力也优于石灰石.碰撞实验表明,该粉末成型的颗粒煅烧后仍有与石灰石相近的抗碰撞破碎强度.煅烧温度越高,颗粒强度减弱;多次循环后颗粒因烧结强度增加.基于Rittinger磨损理论,结合碰撞数据发展了计算吸收剂碰撞破碎后平均粒径的半经验预测公式.该机械成型、水泥支撑的吸收剂兼具较好的脱碳活性及机械强度.%Cement support and granulation were used to synthesize calcium sorbent. CO2 capacity was investigated in a quartz bubbling fluidized bed. A particle impact apparatus was employed to evaluate the mechanical strength. The morphology and porosity of the sorbents were also assessed by scanning electron microscope and N2 absorption/desorption. The synthesized sorbents doped with 10% aluminum cement during pelletisation showed higher sintering resistance and lower porosity decaying than raw limestone. Thus,the cyclic reactivity of the synthesized pellets calcined at 850℃/N2 or 950℃/100%CO2 was superior to limestone. The less fine particles in reactor after multiple cycles exhibited higher attrition resistance to synthetic sorbents. The impact tests also showed that the pellets formed from powder still possessed similar impact breakage resistance to limestone after calcination. High calcined temperature decreased the strength of pellets,which could be improved by sintering after multiple cycles. A semi-empirical formula for calculating the average diameter after impact breakage based on Rittinger's surface theory was developed. This sorbent could acquire good reactivity without expense of strength decaying.
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