The effects of catalyst on gas yields and gaseous compound contents of Inner Mongolia lignite with different particle si-zes are investigated by pyrolysis tests performed in a fixed-bed reactor. The crystalline structures characteristics of chars are deter-mined by methods of XRD. The results show that the pyrolysis gas yield of lignite,which is either raw coal or supported catalyst,de-creases as the particle size increases. For gaseous compound contents,the content of CO2increases with the increase of particle size, but contents of CO, H2, CH4show opposite trends. In case of the same particle size, pyrolysis gas yields of lignite with catalyst is slightly larger than those of the raw coal samples,and with the increase of catalyst loading,contents of CO2and CH4produced by pyrol-ysis increase,but contents of H2and CO decrease. The degree of graphitization of the char with relatively large particle size is relatively low,due to the incomplete devolatilization of the char. In addition,when the particle size is the same,the crystallite structure of the char with catalyst is disordered, and the process of graphitization becomes more and more hindered with the increase of the catalyst loading.%以内蒙褐煤为研究对象,在固定床反应器上考察了催化剂对不同粒径褐煤热解过程中的各气体组分含量以及产气率的影响,通过XRD研究了热解后煤焦的微晶结构特性.研究结果表明:无论是原煤还是负载催化剂的褐煤,随着粒径增大,其热解产气率下降;对于各气体组分,CO,H2,CH4含量均随原煤颗粒粒径增大而下降,CO2却呈相反趋势.而在粒径相同的情况下,负载催化剂的试样热解产气率稍大于原煤试样,且随着催化剂含量的增大,产气率提高,试样热解产生的CO2和CH4含量呈增加趋势,但H2,CO含量却有所下降.对于粒径较大的试样,由于挥发分脱除不够完全,生成的煤焦碳化程度较低,使得煤焦石墨化程度也较低.此外,当粒径相同的情况下,负载催化剂的煤焦碳微晶结构越无序,则随着催化剂负载量的增加,越阻碍试样石墨化的进程.
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