玉米芯热重分析及气化反应动力学研究

Thermo-gravimetric analysis and gasification reaction kinetics of corn cob

利用热重分析实验得出玉米芯气化可大致分为3个阶段:水分蒸发、挥发分析出和焦炭阶段.研究表明,当升温速率为20℃/min时,物料的最大失重率只有85.75%,在所有的升温速率中最小;当升温速率为10℃/min时,物料的最大失重率可达到97.94%.以升温速率为5℃/min的热重曲线研究玉米芯气化过程中的挥发分析状况,当温度在250℃～330℃时,气化反应属于2级反应,其拟合方程y=-2 332.3x-7.953 4,活化能E和指前因子A分别为19.4kJ/mol和3.4×104 min-1;温度在330℃～530℃时,气化反应属于1级反应,其拟合方程y=-1 960.5x-9.707 6,活化能E和指前因子A分别为16.3kJ/mol和5.0×103 min-1.

The corn cob gasification can be divided into three stages by using thermo-gravimetric analysis experiment in this paper.Water evaporation stage,volatile precipitation stage and coke stage;When heat- ing rate is 20 ~C/min,the material of the biggest weightlessness rate is only 85.75%, the smallest of all the heating rate; When heating rate is 10 ℃/min, the biggest weightlessness rate of the material can reach 97.94M. Taking the curve at the heating rate of 5 as the research object,the gasification process of corn cob volatile precipitation stage, under the temperature of 250 ℃ -330 ℃ ,gasification reaction be- longs to level 2 reaction,fitting equation is y=-2 332.3x--7. 953 4 ,the activation energy E and frequen- cy factor A were 19.4 kJ/mol and 3.4× 104 min-1 ;When the temperature at 330 ℃-530 ℃ stage,gasification reaction belongs to level 1 reaction, with fitting equation is y=--1 960.5x--9. 707 6 ,the activation energy E and frequency factor A were 16.3 kJ/mol and 5.0X 103 min-1.