微型流化床反应分析及其对煤焦气化动力学的应用  

Micro fluidized bed reaction analysis and its application to coal char gasification kinetics

作　　者：曾玺[1] 王芳[1,2] 韩江则[1] 张聚伟[1] 刘云义[2] 汪印[1] 余剑[1] 许光文[1] 

机构地区：[1]中国科学院过程工程研究所,多相复杂系统国家重点实验室,北京100190 [2]沈阳化工大学化学工程学院,辽宁沈阳110142

出　　处：《化工学报》2013年第1期289-296,共8页CIESC Journal

基　　金：国家重点基础研究发展计划项目(2011CB201304);科技部重大仪器专项(2011YQ120039);国家自然科学基金项目(21106156,21006110,21076217,51174283);中国科学院战略性先导科技专项“低阶煤清洁高效梯级利用关键技术与示范”(XDA07010100)~~

摘　　要：在概述最新研发的微型流化床反应分析(micro-fluidized bed reaction analysis,MFBRA)方法与应用的基础上,应用该方法进一步研究了半焦-CO2、半焦-水蒸气等温气化反应动力学,并与热重分析(thermogravimet-ric analyzer,TGA)求取的气化反应动力学数据比较。在最小化气体扩散的实验条件下,利用MFBRA和TGA测定求算的半焦-CO2、半焦-水蒸气气化反应在受反应动力学控制的低温段的活化能非常接近,说明了MFBRA对等温气化反应分析的适用性和可靠性。实验研究还发现:半焦-CO2、半焦-水蒸气气化反应在MFBRA中受反应动力学控制的温度范围较在TGA中明显宽,且在具有明显扩散影响的高温段通过MFBRA测定的半焦-CO2气化反应表观活化能明显大于利用TGA测定的值,表明在MFBRA中受到的气体扩散抑制效应较小。After summarizing the newly developed micro-fluidized bed reaction analysis（MFBRA）and its existing applications,its application to the kinetics of isothermal gasification reaction between coal char and CO2/steam were further extended.The resulting kinetic data were compared with the measurements in thermogravimetric analyzer（TGA）.Under minimized limitations of heat and mass transfer,the activation energy of char gasification with CO2 and steam in the kinetically controlled low temperature region was very close to that obtained from TGA,validating the reliability of MFBRA for the analysis of char gasification kinetics.Moreover,the temperature range of the kinetically controlled reaction region was found to be obviously wider in MFBRA than in TGA for both char-CO2and char-steam reactions.At higher temperatures with evident limitations of heat and mass transfer on the reaction kinetics,the estimated activation energy was obviously higher with MFBRA than that with TGA.All of these further demonstrated that the diffusion limitation in MFBRA was weaker than that in TGA for gasification of coal char.

关 键 词：微型流化床 热重 半焦气化 反应动力学 等温反应 

分 类 号：TQ523.2[化学工程—煤化学工程]