木屑及其水解残渣快热解特性研究

Characteristic and Kinetics of Pyrolysis of Sawdust and Its Hydrolysis Residues

生物质水解残渣中主要含有木质素和少量未水解完全的纤维素和半纤维素。研究了木屑以及水解残渣在氮气氛围下的TG和DTG曲线,着重探索残渣的裂解特性,并与木屑的热解特性作了比较,给出残渣热裂解一级平行动力学模型及其频率因子和活化能。研究表明:木质素是木质纤维素类热裂解产生焦碳的主要来源。随着升温速率的提高,生物质热裂解温度和速率明显提高。

Lignin and small amounts of un-hydrolyzed cellulose and hemi-cellulose are the residues of sawdust hydrolysis. Thermal properties of sawdust and its hydrolysis residues were studied using TG (thermogravimetry) and DTG (derivation thermogravimetry) curves obtained in N2 atmosphere. The activation energy and pre-exponential factor for pyrolysis of the residues were estimated from the kinetic models for first order parallel reactions. The results show that lignin is the main source of coke formed in rapid pyrolysis and that increasing the heating rate causes significant increases in both the temperature and rate of sawdust pyrolysis.