黏结性富油煤热解油气析出规律及物性演变特征  

Tar and gas production rules and physical property evolution characteristics during the pyrolysis of cohesive tar-rich coal

作　　者：唐颖 吴晓丹 孙景耀 苏展 畅志兵[3] 王楚楚 旷文昊 TANG Ying;WU Xiaodan;SUN Jingyao;SU Zhan;CHANG Zhibing;WANG Chuchu;KUANG Wenhao(Research&Development Center,CNOOC Gas&Power Group,Beijing 100028,China;Key Laboratory of Liquefied Natural Gas and Low Carbon Technology,China National Offshore Oil Corporation,Beijing 100028,China;School of Chemical and Environmental Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China)

机构地区：[1]中海石油气电集团技术研发中心,北京100028 [2]中国海洋石油集团有限公司液化天然气及低碳技术重点实验室,北京100028 [3]中国矿业大学(北京)化学与环境工程学院,北京100083

出　　处：《洁净煤技术》2024年第1期58-65,共8页Clean Coal Technology

基　　金：国家自然科学基金面上资助项目(51476185);中国矿业大学(北京)越崎杰出学者资助项目(2020JCBO2);中海石油气电集团科技资助项目(QDKY-2023-YFZX-02)。

摘　　要：黏结性富油煤受热产生的软化、熔融现象可能导致井筒堵塞和地层扰动,这是原位热解需考虑的重要因素。在300~700℃下对黏结性富油煤热解,考察油气析出规律和组成性质,分析半焦的物性演变特征及其对原位热解的指示意义。结果表明,焦油产率在500℃取得最大值7.75%,此时<300℃轻质组分含量最高(32.2%),且焦油成分在400~500℃变化显著,酚类和芳烃含量分别呈现增大和降低趋势。煤样的软化温度和固化温度分别为389和455℃,使半焦的宏观孔率度在≥400℃时由不足10%增至约50%,而微观孔隙结构仅在600~700℃高温脱气阶段更发达;半焦导热系数随温度先减小后增大,并在400℃达到最小值0.06 W/(m·℃)。黏结性富油煤原位热解面临通道堵塞、挥发分析出受阻和煤层导热速率偏慢等潜在问题,可尝试采用具有破黏效应的压裂支撑剂或近临界水原位转化技术加以解决。The softening and melting of cohesive tar-rich coal caused by heating may lead to wellbore blockage and formation disturbance,which is an important factor to be considered for in-situ pyrolysis.In this paper,the pyrolysis of cohesive tar-rich coal at 300-700℃was conducted to investigate the oil and gas precipitation rules and their composition properties,and the evolution characteristics of physical properties of semi-coke and its indicative significance for in-situ pyrolysis were analyzed.The results shows that the tar yield reaches the maximum value of 7.75%at 500℃,and the content of light components(boiling point lower than 300℃)of the derived tar is the highest(32.2%).The tar components chang significantly at 400-500℃,and the content of phenols increases while that of aromatics decreases.The softening temperature and curing temperature of the coal sample are 389 and 455℃respectively.Consequently,the macro-porosity of semi-coke increases from less than 10%to about 50%at≥400℃,while the micro-pore structure is more developed only at the high temperature stage of 600-700℃.The thermal conductivity of semi-coke decreases first and then increases with temperature,and reaches a minimum value of 0.06 W/(m·℃)at 400℃.In-situ pyrolysis of cohesive tar-rich coal may be confronted with potential problems such as channel blockage,volatile precipitation obstruction and slow thermal conductivity of coal seam.These problems are expected to be solved by using fracturing proppant with viscosity breaking effect or applying near critical water in-situ conversion technology.

关 键 词：富油煤 黏结性 胶质体 焦油 孔隙结构 导热系数 

分 类 号：TQ536[化学工程—煤化学工程]