利用固定床热解炉在不同热解温度（400~900℃）下制得热解半焦，采用BET和XRD分析手段对不同热解温度的褐煤半焦理化性质进行表征。在高温高压（800℃、4 MPa）条件下，利用固定床反应器对呼伦贝尔褐煤半焦试样进行直接加氢制甲烷的研究。结果表明，呼伦贝尔褐煤半焦在高温高压加氢制甲烷的最优热解温度为600℃；热解温度在600~800℃的半焦加氢反应碳转化率可达82%，产品气中CH₄的质量分数约96%；在400~800℃，半焦比表面积由8 m²/g增大到182 m²/g，半焦加氢反应碳转化率随比表面积的增大而增加，当热解温度高于800℃，半焦中碳结构的晶面间距d₀₀₂减小，堆垛高度L₀₀₂明显增大，d₀₀₂/L₀₀₂从0.472迅速减小为0.365，石墨化程度加深，导致其加氢反应碳转化率迅速下降。

The physicochemical properties of semicoke, which is prepared by pyrolysis of lignite at different temperatures (400-900℃) in a fixed bed pyrolysis furnace, are characterized by BET and XRD respectively.Furthermore, the semicoke made by lignite sourced in Inner Mongolia is used to produce methane through hydrogasification in a fixed bed reactor at high temperature (800℃) and high pressure (4 MPa).The results show that the optimum pyrolysis temperature is 600℃ for the pyrolysis of the lignite sourced in Inner Mongolia.The carbon conversion rate of hydrogenation of the semicoke prepared through pyrolysis at 600-800℃ can reach 82%, with the mass fraction of methane in gaseous products being about 96%.The specific surface area of the semicoke prepared through pyrolysis at 400-800℃ increases from 8 m²·g^-1 to 182 m²·g^-1 and the carbon conversion rate of that increases with the increasing specific surface area.When the pyrolysis temperature exceeds 800℃, the interplanar crystal spacing d₀₀₂ decreases and stacking height L₀₀₂ increases sharply, leading to a sharp drop of d₀₀₂/L₀₀₂ from 0.472 to 0.365.It indicates the graphitization process of semicoke structure deepens obviously, which causes the carbon conversion rate of semicoke hydrogenation to decrease rapidly.

郝五兴(1992-),男,硕士研究生,主要从事煤/焦气化方面研究,1870530331@qq.com。