PDF《氢气压力对煤加氢反应影响的热重 - 气相色谱实验研究》

文章编号: 0253鄄2409(2015)08鄄0914鄄09 摇 收稿日期: 2015鄄01鄄22;

修回日期: 2015鄄03鄄14.

摇 基金项目: 国家高技术研究发展计划(863 计划, 2011AA05A201). 摇 联系作者: 张建胜, 教授, Tel/ Fax: 010鄄62795930, E鄄mail: zhang鄄jsh@ tsinghua. edu. cn. 氢气压力对煤加氢反应影响的热重-气相色谱实验研究 管清亮, 毕大鹏, 玄伟伟, 张建胜 (清华大学热能工程系 热科学与动力工程教育部重点实验室, 北京摇 100084) 摘摇 要: 采用加压热重分析仪和气相色谱仪联用的方法研究了府谷烟煤和海拉尔褐煤加氢反应过程中的失重规律和主要气 体产物析出规律,升温速率

15 益/min,压力 0.

1 ~ 5.

0 MPa,反应终温

1 000 益. 实验结果表明,煤粉加氢反应主要分为初始干 燥脱气、热分解及挥发分加氢,半焦加氢气化和焦炭加氢气化四个阶段. 氢气压力的提高促进了挥发分自由基的加氢反应, 抑制了含氧官能团脱除形成碳氧化物. 在热分解及挥发分加氢阶段,府谷烟煤失重速率随氢气压力的升高而减小,氢气压力 对海拉尔褐煤失重速率的影响不大. 在半焦加氢气化阶段,CH4 生成速率随氢气压力的升高而增大,当氢气压力较高时(3 ~

5 MPa),海拉尔褐煤 CH4 生成速率随氢气压力的升高不再增大. 海拉尔褐煤 Odaf 较高,其半焦中含氧官能团提供的活性位较 多. 府谷烟煤 H/ C 原子比较高,能提供更多的内部氢. 府谷烟煤和海拉尔褐煤焦炭加氢反应动力学参数分别为 k0 = 2. 38伊107 (min-1 ・ MPa-1 ),E=231 kJ/ mol,n=1 和k0 =2. 64伊103 (min-1 ・ MPa-0.

736 ),E=127 kJ/ mol,n=0. 736. 关键词: 加氢热解;

加氢气化;

压力;

热重分析 中图分类号: TQ530摇摇文献标识码:A Thermogravimetric鄄gas chromatographic study on effects of hydrogen pressure on coal hydrogenation GUAN Qing鄄liang, BI Da鄄peng, XUAN Wei鄄wei, ZHANG Jian鄄sheng (Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing摇100084, China) Abstract: Thermogravimetric characteristics and evolution of main gaseous products during hydrogenation of two coals were studied in a thermogravimetry鄄gas chromatography combined system at

15 益/min, 0.

1 ~

5 MPa and a final temperature of

1 000 益. The results show that the hydrogenation process occurs in four stages: drying and degassing, hydropyrolysis, rapid hydrogasification, and slow hydrogasification. With increasing hydrogen pressure, hydrogenation of volatile radicals is promoted and decomposition of oxygen鄄containing functional groups forming carbon oxides is inhibited. During hydropyrolysis stage, the weight loss rate increases with hydrogen pressure for FG coal, while the hydrogen pressure has little influence on that for HLE coal. During the rapid hydrogasification stage, the evolution rate of CH4 increases with hydrogen pressure;

for HLE coal the evolution rate of CH4 doesn忆t increase with hydrogen pressure any more at high pressures (3 ~

5 MPa). The HLE coal with higher oxygen content contains more active sites provided by the oxygen鄄containing groups in the semi鄄char. The FG coal with higher H/ C atomic ratio is able to provide more hydrogen by itself during hydrogenation reactions. The kinetic data of the slow hydrogasification stage is k0 =2. 38伊107 (min-1 ・ MPa-1 ), E =231 kJ/ mol, n =1 for the FG coal and k0 =2. 64伊103 (min-1 ・ MPa-0.

736 ), E =127 kJ/ mol, n =0.