桉树木屑成型颗粒成分变化和燃烧特性的研究

STUDY ON COMPOSITION AND COMBUSTION PROPERTIES OF EUCALYPTUS SAWDUST PELLETS

以中国南方典型生物质桉树木屑的成型颗粒作为研究对象,将成型颗粒分层剥离后,利用热重分析技术对原料和剥离层进行燃烧特性分析,研究桉树木屑成型前后燃烧特征参数的变化,并采用Coasts积分法计算燃烧反应动力学参数。结果表明:成型颗粒着火温度降低,外层燃料的可燃性和燃烧特性得到改善;挥发分的析出和燃烧阶段的活化能和指前因子变大,固定碳燃烧阶段的活化能和指前因子变小,这表明桉树木屑在压缩成型后,在挥发分的析出和燃烧阶段热稳定性得到改善,燃烧变得困难,而在固定碳燃烧阶段热稳定性变差,燃烧变得容易。

In this paper,pellets made of eucalyptus sawdust which is a typical biomass in southern China were taken as the research object.Raw materials and the delaminated layer of pellets were carried out to study the combustion characteristics changes by thermogravimetric analysis technology,and the combustion reaction kinetics parameters were calculated by Coasts integral method.The results showed that while the ignition temperature of the pellets decrease,the flammability and combustion characteristics of the outer fuel become better,the activation energy and pre-exponential factor increase in the devolatilization and combustion stage,but decrease in the fixed carbon combustion stage,which indicates that the thermal stability of eucalyptus sawdust becomes better and more difficult to burn after molding,while the thermal stability becomes worse and easier to burn in fixed carbon combustion stage.