水蒸气对钙基吸收剂循环煅烧/碳酸化CO_2捕集过程中孔结构的影响  

Effect of Steam on the Pore Structure of Ca-based Sorbent During Looping for CO_2 Capture

作　　者：王春波[1] 周兴[1] 张斌[1] 白彦飞[1] 

机构地区：[1]华北电力大学能源动力与机械工程学院,河北省保定市071003

出　　处：《中国电机工程学报》2015年第2期390-395,共6页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51276064);北京市自然科学基金项目(3132028)~~

摘　　要：利用自制等温测量热重实验台,对钙基吸收剂循环煅烧/碳酸化工艺中水蒸气对吸收剂孔结构影响进行了研究。仅煅烧阶段含有水蒸气时,转化率最低,而仅碳酸化阶段存在水蒸气时,取得最高的碳酸化转化率。煅烧阶段和碳酸化阶段均含有水蒸气与仅碳酸化阶段存在水蒸气转化率类似。采用氮吸附测试了典型工况下的Ca O孔结构。随着循环次数增加,碳酸化转化率降低,比表面积、孔容积逐渐减小。推测煅烧阶段水蒸气通过烧结降低了碳酸化转化率。碳酸化阶段水蒸气通过催化作用提高了转化率,此时孔结构作用并不占主动地位。煅烧和碳酸化均存在水蒸气时,碳酸化阶段水蒸气催化作用更加明显。A customized TGA that can measure sample weight change at constant temperature was used to study the effect of steam on pore structure evolution of sorbent. Steam only in calcination process results in the lowest CaO carbonation conversion in the following carbonation. The presence of steam in carbonation stage achieved the highest carbonation ratio. When it contains steam at both calcination and carbonation stage, the carbonation ratio is very similar that at only carbonation stage contaions steam. Pore structure of sorbents at typical operational parameters were tested by N2-adsorption method. It shows with more cycle numbers,specific surface area and pore volume would be decreased.During calcined stage, steam reduces the carbonation conversion through sintering; while carbonation stage, steam plays catalytic role and the effect of pore structure does not account for that much. When steam presents both calcination and carbonation, the catalytic role affect will be more obvious.

关 键 词：钙基吸收剂 煅烧/碳酸化 孔结构 水蒸气 影响机理 

分 类 号：TQ424[化学工程]