煤泥热解和燃烧过程的行为特性研究

In order to study the thermochemical conversion characteristics of coal slime,pyrolysis and combustion experiments at different heating rates (10 ℃ / min,20 ℃ / min,30 ℃ / min) were carried out using a thermogravimetric analyzer. Two kinetic methods of calculation,Flynn Wall Ozawa (FWO) and Kissinger Akahira Sunose (KAS),were used to calculate and compare the kinetic parameters of coal slime pyrolysis and combustion process. The results indicate that with the increase of heating rate,the thermal gravimetric (TG) and differential thermal gravimetric (DTG) curves of pyrolysis and combustion of coal slime shift towards high temperature direction. The DTG curve of the coal slime pyrolysis mainly presents two obvious weight loss peaks. During the combustion process,due to the overlap of volatile and fixed carbon combustion processes,a significant weight loss peak appears in the DTG curve within the range of 300—580 ℃, and the burnout time decreases with the increase of heating rate. The activation energies of the first stage of coal slurry pyrolysis calculated by the FWO method and KAS method were 175.78 kJ / mol and 163.40 kJ / mol,respectively,and the activation energies of the second stage of pyrolysis were 225.37 kJ / mol and 209.51 kJ / mol,respectively. The activation energies of coal slurry combustion process calculated by the FWO method and KAS method are 109. 12 kJ / mol and 102. 65 kJ / mol, respectively. The results obtained by these two methods have good consistency,and the comprehensive use of the two kinetic calculation methods is conducive to forming a more comprehensive understanding of the pyrolysis and combustion process of coal slurry.