CO_2对CaS氧化反应的影响  

Effect of CO_2 on Oxidation of CaS

作　　者：宋占龙[1] 董勇[1] 章名耀[2] 

机构地区：[1]山东大学能源与动力工程学院,济南250061 [2]东南大学热能工程研究所,南京210096

出　　处：《燃烧科学与技术》2009年第4期316-320,共5页Journal of Combustion Science and Technology

基　　金：国家"十一五"科技支撑计划重点资助项目(2006BAA01B04);山东省优秀中青年科学家科研奖励基金资助项目(2006BS08024)

摘　　要：煤气化钙剂脱硫产物CaS是一种不稳定的化学物质,氧化是使其稳定的有效方法.在加压热重分析仪上进行了CaS的氧化试验,重点考察了CO2摩尔分数对CaS反应产物的影响,并利用傅里叶变换红外光谱(FTIR)法对反应固体产物进行了定量分析.研究发现,CO2气体的存在对于CaS的氧化反应有显著影响.CO2能直接与CaS发生反应,一定程度上提高了CaS的转化率.CO2分压对CaS的氧化反应影响较大.相对于低CO2分压,高CO2分压下反应产物中CaCO3的摩尔分数较高,而CaS的转化率较低.原因在于CaCO3和CaCO3分解生成的CaO摩尔体积的不同,导致了反应气体在颗粒内的扩散特性有所差异.CaS, generated from H2 S removal process using calcium-based sorbents during coal gasification, is an unstable and hazardous chemical, and can be converted to stable and safe substances such as CaO, CaCO3 and CaSO4. Using Fourier transform infrared spectroscopy （FFIR） technique, the effects of molar contents of CO2 on CaS oxidation were investigated in a pressurized thermogravimetric analyzer. The experimental results show that CO2 can accelerate conversion of CaS via direct reaction. The partial pressure of CO2 greatly affects the reaction of CaS oxidation. The molar contents of CaCO3 under higher partial pressure of CO2 are higher than those under lower partial pressure of CO2, and the CaS conversion shows the reverse trend. The most possible reason is the difference between the molar volumes of CaCO3 and CaO, resulting in different diffusion of reactant gases in particles.

关 键 词：CAS 氧化 CO2 加压热重分析 傅里叶变换红外光谱 

分 类 号：X705[环境科学与工程—环境工程]