(中南大学 资源加工与生物工程学院，长沙 410083)
摘 要: 采用钒钛磁铁矿为氧载体对生物质的气化转化行为进行研究，系统考查转化温度、氧载体比例等关键因素的影响。借助热重-差热分析(TG-DSC)、傅里叶红外光谱(FTIR)、气相色谱-质谱联用(GC-MS)、X射线衍射(XRD)等分析测试手段对气化过程产物特性进行表征并揭示生物质转化机制。结果表明：温度升高有利于生物质的气化转化，所得气相产率和气相产物中CO及H2占比皆显著增大；气相产物的释放主要集中在转化过程的前20 min，CH4、C2H4和CO2等成分的析出率先达到峰值，CO和H2的析出率达到峰值略有滞后；氧载体的加入可加快生物质各基团的裂解，促进固、液相产物向气相产物的转化。生物质的裂解转化历程可概括为—OH、—C=O、—C=C→—CH3→—CH→—CO，此过程中钒钛磁铁矿逐渐被还原为金属化产品(金属化率可达80%以上)。
关键字: 生物质；气化转化；氧载体；钒钛磁铁矿；气质联用
（School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China）
Abstract:The conversion behavior of biomass gasification using vanadium titanomagnetite as oxygen carrier was studied. The key factors of conversion temperature and oxygen carrier ratio were investigated. The process products of gasification were characterized by applying thermogravimetric-differential thermal analysis (TG-DSC), fourier transform infrared spectroscopy (FTIR), gas chromatography-mass spectrometry (GC-MS), X-ray diffraction (XRD) and other analytical methods to reveal the conversion mechanism of biomass. The results show that increasing temperature is beneficial to gasification conversion, the gas phase yield and the proportions of CO and H2 in gas phase show a remarkable uptrend. The release of gas products mainly concentrates in the first 20 min. The release rate of CH4, C2H4, CO2 reach peak firstly, while the release rate of CO and H2 lag slightly. The oxygen carrier can accelerate the pyrolysis of various groups and promote the conversion of solid and liquid phase products to gas phase products. The pyrolysis and conversion process of biomass can be summarized as follows —OH, —C=O, —C=C→—CH3→—CH→—CO. During this process, vanadium titanomagnetite is gradually reduced to metallized product (metallization ratio＞80%).
Key words: biomass; gasification; oxygen carrier; vanadium titanomagnetite; gas chromatography-mass spectrometry
