黑液与石油焦共热解及其产物特性研究

Co-pyrolysis behaviors and products characteristics of black liquor and petroleum coke

运用热重-红外联用(TGA-FTIR)和扫描电镜(SEM)对黑液与石油焦的共热解过程进行了实验研究,考察了两者在共热解过程中的热失重、挥发性组分释放及固体产物表面形貌特性;同时运用热重(TGA)探究了热解固体产物黑液半焦和石油焦的CO2共气化反应特性。结果表明,在黑液与石油焦共热解过程中,温度低于600℃时,两者的热解相互独立;温度达到600℃之后,相对于黑液和石油焦单独热解的加权平均值,挥发性气体产物CO2和CO的释放峰值温度向低温区移动,失重特性也随之发生变化;800℃下的共热解固体产物表面产生新的形态特征,黑液的烧结得到抑制;850℃下的黑液半焦与石油焦CO2共气化实验表明,两者在共气化过程中存在协同效应,各自的碳转化率和气化速率明显提高,整体碳转化率提高了51.27%,气化反应速率最大值增大了两倍。

The weight loss characteristics,evolution patterns of volatiles and morphology of solid product from co-pyrolysis of black liquor and petroleum coke were studied by a thermo gravimetric analyzer coupled with Fourier Transform Infrared Spectrometry（TGA-FTIR） and scanning electronic microscopy（SEM）. The CO2cogasification characteristics of black liquor char and petroleum coke were also investigated by thermo gravimetric analyzer（TGA）. The results suggested that the pyrolysis reactions had proceeded independently during copyrolysis process at temperatures below600 ℃. However,as the temperature exceeded 600 ℃,the release peak temperature of CO2and CO were shifted to lowtemperature zone,and the thermo gravimetric characteristics were changed in contrast with the separate pyrolysis. Moreover,the surface morphology of the solid products from copyrolysis had been changed dramatically at 800 ℃. Specifically,the sintering during pyrolysis of black liquor was inhibited by the presence of petroleum coke. Compared to the individual gasification,the carbon conversion and gasification rate had been greatly improved for CO2co-gasification due to the synergistic effect of the blends at 850 ℃. The overall carbon conversion were increased by 51. 27%,meanwhile,the maximum gasification rate were improved by twice during CO2co-gasification process.