玉米秸秆成型颗粒快速燃烧特性及反应动力学研究

STUDY OF RAPID COMBUSTION CHARACTERISTICS AND REACTION DYNAMICS OF CORN STRAW BRIQUETTE

基于等温热重分析技术,采用化学动力学法拟合燃烧过程中质量损失率与时间的单方程模型,对不同燃烧温度与成型密度下柱状玉米秸秆成型颗粒的快速燃烧特性进行研究。结果表明:玉米秸秆成型颗粒在600℃下成型密度较大,燃尽时间较长,到达热失重速率(DTG)曲线峰值时间较长;相同密度的成型颗粒,随温度的升高,燃尽时间缩短,DTG峰值高度越高,到达峰值的时间越短;在该实验变量控制范围内,成型密度和外部环境温度对燃尽率无明显作用;通过动力学计算得到玉米秸秆成型颗粒的反应级数在0.5~0.7之间。由实验数据曲线拟合得到拟合方程,求解出活化能E及指前因子A。

The rapid combustion characteristics of corn stalk briquette with different formation density and combustion temperature were studied by isothermal thermogravimetric analysis technique and the single equation model of mass loss rate and time in combustion process simulated by using a chemical dynamics. The results show that the burnout time of corn stalk briquette will be longer with the larger formation density under 600 ℃, and the time of reaching peak of DTG curve more longer; It is verified that the burnout time of formation briquette with the same density is shortened with the increase of combustion temperature, and the peak value of DTG curve is be higher, and time of reaching peak of curve is shorter. In the range of the experimental variables, the results show that the formation density and external temperature have no obvious affect on burn off rate. The calculation results of dynamics show that the reaction order of corn stalk formation briquette is in the range of 0.5-0.7. The activation energy E and pre-exponential factor A are solved from fitting equation obtained by curve fitting of experimental data.