间接加热回转窑在油页岩热解中的工程应用

Engineering application of indirect heating rotary kiln in oil shale pyrolysis treatment

在国内率先采用间接加热回转窑热解工艺对小颗粒油页岩开展了工程实验项目。以辽宁小颗粒油页岩为原料,利用间接加热回转窑成套设备考察了油页岩热解工艺的运行效能。结果表明,当出料温度为500℃以上,停留时间20~45 min时,油页岩热解的油回收率可达到88%,高于抚顺炉和ATP技术;页岩半焦仍保留一定的热值,有机质含量最高达到4.1%,可进一步用于资源化利用;当油页岩处理量达4.5 t·h^(−1)时,天然气能耗为40.1m^(3)·t^(−1);与ATP等工艺相比,间接加热回转窑热解系统中粉尘含量大幅度降低,携尘率仅为1.2%,无粉尘堵塞管路情况发生,且油页岩热解过程中回转窑内壁不易板结,设备运行稳定,维护成本低。本研究结果验证了间接加热回转窑工艺及设备处理小颗粒油页岩的可行性,为小颗粒油页岩热解规模化应用提供了重要的工艺参数。

It is the first time in China to utilize indirect heating rotary kiln pyrolysis technology to conduct engineering experiments on small particle oil shale.With small-sized oil shale from Liaoning Province as raw material,the performance of oil shale pyrolysis process was investigated through indirect heating rotary kiln equipment.The results showed that when the discharge temperature was above 500℃and the residence time is 20~45 min,the oil recovery rate of oil shale pyrolysis can reach 88%,which was higher than that of Fushun furnace and ATP technology.The shale coke still retained some calorific value,and the maximum organic matter content could reach 4.1%,which could be further resourcefully utilized.When the oil shale processing capacity reached 4.5 t·h^(−1),the natural gas energy consumption was 40.1 Nm3·t^(−1).Compared to the ATP process,the dust content in the indirect heating rotary kiln pyrolysis system was significantly diminished,and the dust carrying rate was only 1.2%.Meanwhile,there was no dust blockage in the pipeline and the inner wall of the rotary kiln was not liable to compact during the oil shale pyrolysis process,resulting in the stable operation and low maintenance cost.The research results verified the feasibility of the indirect heating rotary kiln process and equipment to treat oil shale of small particles,and provided critical process parameters for the large-scale application of small-particle oil shale pyrolysis.