微波改性对水煤浆焦气化的影响规律

Effects of microwave modification on char gasification of coal water slurry

为了揭示微波辐照改善煤粉理化特性对提高水煤浆气化性能的影响,采用黏度计、加压热天平和能谱仪等,研究微波改性对水煤浆焦常压和加压气化反应的促进规律.实验发现随着微波时间增加,水煤浆焦的常压气化温度和活化能都有所降低,并且随着压力升高使得气化温度和活化能逐渐降低.当微波时间增加到120s时,菲律宾水煤浆焦的常压气化活化能从222kJ·mol-1降低到207kJ·mol-1,而当气化压力增加到0.6MPa时活化能降低到185kJ·mol-1.由菲律宾褐煤制成的水煤浆焦气化反应活性要高于贵州贫煤制成的水煤浆焦,而气化活化能规律正好相反.结果表明微波辐照不仅能提高水煤浆的制浆浓度,还能增强水煤浆焦的气化反应性.

Microwave irradiation was employed to modify coal physicochemical property to promote gasification performances of coal water slurry （CWS） gasification performances. The improvement of microwave modification on CWS char gasification at atmospheric and elevated pressures was investigated on a rotary viscometer, pressurized thermobalance and energy disperse spectroscopy. Both the gasification temperatures and activation energy of CWS char decrease with increasing microwave time and gasification pressure. The gasification activation energy of Filipine CWS char decreases from 222 kJ · mol^-1 to 207kJ · mol^-1at atmospheric pressure after a microwave time of 120 s, and further decreases to 185 kJ · mol^-1 when gasification pressure increases to 0. 6 MPa. The gasification reactivity of CWS char prepared from Filipine lignite is higher than that prepared from Guizhou lean coal, but the gasification activation energy is in reverse. Therefore microwave irradiation not only increases CWS solid concentration, but also increases CWS char gasification reactivity.