Regularity of Gaseous Product Release During Direct Coal Liquefaction Residue Pyrolysis Process

The pyrolysis characteristic of direct coal liquefaction residue (DCLR) was studied with thermo-gravimetric analyzer (TG) coupled with Fourier transform infrared spectrometry (FTIR), which is used to discuss the emitted regulation of gaseous product during pyrolysis process. This research shows that the weight loss process of DCLR can be divided into three stages: the first is before the temperature of 405. 10 degrees C; stage from 405. 10 to 523. 83 degrees C which is mainly pyrolysis of high boiling point of oil and asphaltene et al, and the total weight loss of DCLR can up to 40. 27% when the temperature reaches 478. 45 degrees C, meanwhile the mass loss rate is maximum; after 523. 83 degrees C, the weight loss curve becomes gentle and the total weight loss of DCLR reaches 50. 55%, which is due to the secondary cracking of residue and decomposition of mineral matter. The emitted process of gaseous product can be divided into three stages too: the first is the generation of H2O and CO2, the second stage mainly emitted CO2, CH4, CO, H2O and a small quantity of SO2, in which plenty of tar is generated from 458. 4 to 791. 9 degrees C, the final stage mainly generated CO2, CO and H2O. CO2 mainly emitted owing to the cracking of oxygenheterocycle and O-C=O or other oxygen containing groups, CO emitted due to cracking of ether and oxygenheterocycle, and CH4 generated as a result of cracking of aliphatic hydrocarbon.