石灰石煅烧/碳酸化过程中微观结构的演变特性  

Microstructure Evolution of Procedural Products During Limestone Calcination and Carbonation

作　　者：危日光[1] 陈江涛[1] 陈鸿伟[1] 陈龙[1] 

机构地区：[1]华北电力大学能源动力与机械工程学院,保定071003

出　　处：《动力工程学报》2013年第2期147-152,159,共7页Journal of Chinese Society of Power Engineering

基　　金：国家自然科学基金资助项目(50876030);中央高校基本科研业务费专项资金资助项目(11MG46)

摘　　要：对石灰石煅烧/碳酸化过程中微观结构的演变特性进行了研究.结果表明:石灰石不同煅烧/碳酸化阶段产物的氮吸附/脱附等温线为Ⅳ型,并在煅烧过程和碳酸化初期存在H1型吸附滞后环;石灰石煅烧产物的比表面积和比孔容随煅烧时间的增加呈线性增加,而碳酸化产物的比表面积和比孔容随碳酸化时间的增加呈指数规律迅速衰减;石灰石完全分解产物的孔容分布曲线呈双峰结构,随着煅烧反应的进行,双峰峰值不断增大,而碳酸化反应导致峰值减小;微孔、中孔和大孔对孔容积和孔面积的增加贡献不同,微孔只对孔面积的增加有一定的贡献,而中孔和大孔对孔容积和孔面积的增加皆有较大的贡献;随着比表面积和比孔容的增大,石灰石煅烧转化率呈线性增大趋势,而CaO的碳酸化转化率呈指数衰减.Microstructure evolution of procedural products during limestone calcination and carbonation was studied. Results show that the procedural products exhibit a type IV nitrogen adsorption-desorption iso- therm at different stages of limestone calcination and carbonation, including a typical H1 hysteresis loop during calcination and initial carbonation process. The specific surface area and pore volume of calcined products increase linearly with the calcination time, while those of carbonated products reduce exponential- ly with the carbonation time. The pore volume of completely decomposed products of limestone distributes in bimodal shape, of which the peak values rise with calcination reaction and reduce with carbonation reac- tion. Different types of pores make a different contribution to the pore volume and area. The micro-pore only makes a certain amount of contribution to the pore area, while the meso-pore and macro-pore make a large contribution to both of them. With the rise of specific surface area and pore volume, the calcination conversion rate of limestone increases linearly and the carbonation conversion rate decays exponentially.

关 键 词：石灰石 煅烧 碳酸化 微观结构 比表面积 比孔容积 氮吸附 氮脱附 

分 类 号：TQ028[化学工程]